Proposed is a method for producing a sintered ore with which it is possible to prevent yield reduction when using a carbon material having a low combustion start temperature. A method for producing a sintered ore that creates a granulated raw material for sintering by granulating a blended sintering raw material containing a carbon material as a solid fuel and sinters the granulated raw material for sintering to obtain a sintered ore, wherein the carbon material is a blend of two or more types of carbon material and is sintered using a blend having a weight average of the sintering start temperature of 550°C or more. Preferably, one with a sintering start temperature of less than 550°C is used as part of the two or more types of carbon materials.
This defect occurrence factor estimation device comprises: a defect occurrence depth calculation means for calculating a depth position, in a slab stage, of a surface defect in a product; a defect occurrence rate calculation means for calculating a defect occurrence rate for each slab depth; an inclusion adhesion rate calculation means for calculating an inclusion adhesion rate for each distance from a solidification start position during slab molding, on the basis of the defect occurrence rate for each slab depth; and a defect occurrence factor estimation means for estimating a defect occurrence factor, by selecting a portion of production conditions by using an estimation model that is trained in advance and that receives the production conditions of the product as input data and outputs the inclusion adhesion rate as output data, and estimating an inclusion adhesion rate in the case where the selected production conditions are changed stepwise.
The method includes slab-heating a steel slab to a temperature of higher than a γ-phase precipitation temperature and 1380° C. or lower, subjecting the steel slab to rough rolling including at least two passes of rolling at a predetermined temperature with an introduced sheet thickness true strain εt of 0.50 or more and to finish rolling with a rolling finish temperature of 900° C. or higher to obtain a hot-rolled sheet, cooling the hot-rolled sheet for 1 second or longer at a cooling rate of 70° C./s or higher within 2 seconds after finish rolling, coiling the sheet at a coiling temperature of 600° C. or lower, performing hot-rolled sheet annealing for soaking at a predetermined soaking temperature, and then performing cold rolling, primary recrystallization annealing, and secondary recrystallization annealing.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
The method includes slab-heating a steel slab to a temperature of higher than a γ-phase precipitation temperature and 1380° C. or lower, subjecting the steel slab to rough rolling including at least two passes of rolling at a predetermined temperature with an introduced sheet thickness true strain εt of 0.50 or more and to finish rolling with a rolling finish temperature of 900° C. or higher to obtain a hot-rolled sheet, cooling the sheet for 1 second or longer at a cooling rate of 70° C./s or higher within 2 seconds after finish rolling, coiling the sheet at a coiling temperature of 600° C. or lower, performing hot-rolled sheet annealing for soaking at a predetermined soaking temperature, and then performing cold rolling, primary recrystallization annealing, and secondary recrystallization annealing.
A TIG welded joint in a high-Mn content steel material that can be formed with reduced occurrence of hot cracking during the welding process and has high strength and excellent cryogenic impact toughness. In the TIG welded joint, the high-Mn content steel material has a chemical composition including, by mass %, C: 0.10 to 0.80%, Si: 0.05 to 1.00%, Mn: 18.0 to 30.0%, P: 0.030% or less, S: 0.0070% or less, Al: 0.010 to 0.070%, Cr: 2.5 to 7.0%, N: 0.0050 to 0.0500%, and O: 0.0050% or less, the balance being Fe and incidental impurities, and a weld metal has a chemical composition including C: 0.10 to 0.80%, Si: 0.05 to 1.00%, Mn: 15.0 to 30.0%, P: 0.030% or less, S: 0.030% or less, Al: 0.100% or less, Cr: 6.0 to 14.0%, and N: 0.100% or less, the balance being Fe and incidental impurities.
A steel sheet has a certain chemical composition and a steel microstructure containing, in area fraction, martensite: 40% or more and 78% or less, bainite: 20% or more and 58% or less, and retained austenite: 2% or more. Carbides in tempered martensite in the martensite have an average particle size of 0.40 μm or less, an average amount of C in the retained austenite is 0.5% by mass or more, a Si concentration in a region within 100 μm in a thickness direction from a surface of the steel sheet is 1.3% by mass or less, and a tensile strength is 1,470 MPa or more.
A steel sheet has a chemical composition containing, by mass %, C: 0.20% or more and 0.40% or less, Si: more than 1.0% and 3.0% or less, Mn: 1.5% or more and 3.5% or less, P: 0.002% or more and 0.010% or less, S: 0.0002% or more and 0.0020% or less, sol. Al: 0.40% or less (not including 0%), and N: 0.0100% or less, with the balance being Fe and incidental impurities; and a steel microstructure containing, in area fraction, tempered martensite: 45% or more and 83% or less, bainite: 15% or more and 53% or less, and retained austenite: 2% or more. Carbides in the tempered martensite have an average particle size of 0.40 μm or less, an average amount of C in the retained austenite is 0.5% by mass or more, and a tensile strength is 1,470 MPa or more.
C22C 38/02 - Ferrous alloys, e.g. steel alloys containing silicon
C22C 38/04 - Ferrous alloys, e.g. steel alloys containing manganese
C22C 38/06 - Ferrous alloys, e.g. steel alloys containing aluminium
C22C 38/08 - Ferrous alloys, e.g. steel alloys containing nickel
C22C 38/12 - Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium or niobium
C22C 38/14 - Ferrous alloys, e.g. steel alloys containing titanium or zirconium
C22C 38/16 - Ferrous alloys, e.g. steel alloys containing copper
C22C 38/22 - Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
C22C 38/24 - Ferrous alloys, e.g. steel alloys containing chromium with vanadium
C22C 38/28 - Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
C22C 38/34 - Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
C22C 38/38 - Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
8.
RESIDUAL LIQUID AMOUNT DETECTION METHOD AND DETECTION APPARATUS FOR THE SAME, RESIDUAL MOLTEN MATERIAL AMOUNT DETECTION METHOD AND DETECTION APPARATUS FOR THE SAME, AND METHOD FOR OPERATING VERTICAL FURNACE
A residual molten material amount detection method and detection apparatus that can detect a residual amount of molten material in a vertical furnace and a method for operating a vertical furnace by using the detection method. The residual molten material amount detection method detects a residual amount of molten material remaining in a bottom portion of a vertical furnace after end of discharge of the molten material. The method includes detecting the residual amount of the molten material by using a difference between a production speed of the molten material and a discharge speed of the molten material that is calculated by using a discharge acceleration, a discharge period, and an initial discharge speed of the discharge of the molten material through a taphole.
A damage evaluation device for a press-forming die includes: evaluation dies installed in a pressing device configured to press-form a metal material; and an observation device configured to observe damage behavior of a die steel material and surface coating constituting the evaluation dies. The evaluation dies include: a perforating unit configured to form a hole in the metal material; a first shearing unit configured to shear the metal material in which the hole is formed into a predetermined metal component shape; and a second shearing unit configured to separate a metal component from the metal material, and dies of the perforating unit, the first shearing unit and the second shearing unit are formed of the die steel material and have a structure that enables replacement with another die made of predetermined material and applied with predetermined surface coating treatment.
Provided is a galvanized steel sheet having a TS of 980 MPa or more, high YS, excellent ductility, strain hardenability, and hole expansion formability. A base steel sheet has a defined chemical composition and a steel microstructure as follows: area ratio of ferrite: 65.0% or less (including 0%), area ratio of bainitic ferrite: 5.0% or more and 40.0% or less, area ratio of tempered martensite: 0.5% or more and 80.0% or less, area ratio of retained austenite: 3.0% or more, area ratio of fresh martensite: 20.0% or less (including 0%), SBF+STM+2×SMA: 65.0% or more, SMA1/SMA: 0.80 or less, and SMA2/SMA: 0.20 or more.
A press forming analysis method according to the present invention includes: a die model creation step (S1) for creating a die model having a virtual thickness using two-dimensional elements, and setting the boundary conditions of the two-dimensional elements so that the parts of the die model that correspond to the ribs of the real die are rigid and the parts that do not correspond to the ribs are non-rigid; and a press forming load acquisition step (S3) for performing press forming analysis using the die model created in the die model creation step (S1) to acquire the press forming load.
A method for producing a flared or lap joint including a steel sheet and an aluminum-based sheet material through brazing, wherein a preceding laser beam irradiates ahead of a steel sheet joining position and the aluminum-based sheet material in the joining direction to preheat a joining position, an electrically-heated aluminum-based filler wire feeds to the joining position, a following laser beam is irradiated behind the filler wire so the wire melts performin brazing, and the filler wire is fed with a tilt ranging from 0°≤D≤19° to a front or rear side in the joining direction with respect to a line passing through a groove center of the flared joint and is perpendicular to the joining direction, so that a flared joint or lap joint including a steel sheet and aluminum-based sheet material is produced without appearance defects of a bead and with a sufficient joint strength.
A high-strength stainless steel seamless pipe for oil country tubular goods has a composition that contains, in mass %, C: 0.012 to 0.05%, Si: 0.05 to 0.50%, Mn: 0.04 to 1.80%, P: 0.030% or less, S: 0.005% or less, Cr: 11.0 to 14.0%, Ni: 0.5 to 6.5%, Mo: 0.5 to 3.0%, Al: 0.005 to 0.10%, V: 0.005 to 0.20%, Co: 0.01 to 0.3%, N: 0.002 to 0.15%, O: 0.010% or less, and Ti: 0.001 to 0.20%, and in which Cr, Ni, Mo, Cu, C, Si, Mn, N, and Ti satisfy predetermined relations, and the balance is Fe and incidental impurities, the high-strength stainless steel seamless pipe having a steel microstructure with 6 to 20% retained austenite in terms of a volume percentage, a yield strength of 758 MPa or more, and an absorption energy vE−60 at −60° C. of 70 J or more.
C21D 9/08 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
C21D 8/10 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
A laser cutting method for a steel strip, includes cutting a vicinity of a joint obtained by joining a rear end of a preceding steel strip and a front end of a following steel strip by using a pulse-type laser beam, wherein output of the pulse-type laser beam is set to 0.5 kw or more per 1 ms, a processing point diameter of the pulse-type laser beam is set to 0.1 mm or more and less than 0.6 mm, and a ratio between a pulse period time and a down-time is set to 0.3 or more and less than 0.8.
B23K 26/0622 - Shaping the laser beam, e.g. by masks or multi-focusing by direct control of the laser beam by shaping pulses
B21B 15/00 - Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
B23K 26/14 - Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beam; Nozzles therefor
B23K 26/38 - Removing material by boring or cutting
B23K 26/40 - Removing material taking account of the properties of the material involved
15.
PROJECTION POLISHING SYSTEM, PROJECTION POLISHING METHOD, AND METHOD FOR MANUFACTURING STEEL PRODUCT
A projection polishing system comprises: a shape measurement device (3) that measures a three-dimensional shape and orientation of an object material; a projection detection device (4) that detects a projection that is present on a surface of the object material and recognizes the position and shape of the projection; a polishing device (7) provided with a polishing tool for polishing the projection; and a polishing tool control device (5) that calculates a trajectory for movement of the polishing tool on the basis of the measured three-dimensional shape and orientation of the object material, and the detected position and shape of the projection, and controls the polishing device so that the polishing tool moves along the trajectory while changing the angle of contact of the polishing tool with the projection.
B24B 49/12 - Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation involving optical means
B24B 49/16 - Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation taking regard of the load
B25J 13/08 - Controls for manipulators by means of sensing devices, e.g. viewing or touching devices
16.
NONORIENTED ELECTROMAGNETIC STEEL SHEET AND METHOD FOR MANUFACTURING SAME
Provided is a nonoriented electromagnetic steel sheet that achieves both fine magnetic properties and punch-out workability. Further, proposed is a method for manufacturing the nonoriented electromagnetic steel sheet. This nonoriented electromagnetic steel sheet has a component composition containing, in mass%, not more than 0.0050% of C, 2.0-5.0% of Si, 0.2-1.8% of Mn, not more than 0.020% of P, not more than 0.0050% of S, 0.25-2.00% of Al, more than 0.0030% but not more than 0.0150% of N, not more than 0.0050% of O, and 0.01-0.10% of one of or the total of the two of Sn and Sb, the remaining portion being Fe and unavoidable impurities. The number of AlN particles having a particle size not less than 0.8 μm existing in a sheet thickness cross section of the steel sheet in the rolling direction is 10 particles or more per 1 mm2. In this method for manufacturing a nonoriented electromagnetic steel sheet, the heating of a slab is performed using a heat initiation temperature of 300°C or higher and a heating temperature of 1100-1300°C. The annealing temperature of a hot-rolled sheet is set to 800-950°C and the annealing temperature for the finish annealing is set to 850-1050°C.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
Provided is a method for evaluating delayed fracture properties of a metal material, wherein delayed fracture properties caused by hydrogen penetrating into the interior of the metal material due to atmospheric corrosion can be accurately evaluated and delayed fracture properties in actual usage environments can be simulated. In this method for evaluating delayed fracture properties of a metal material, a step comprising the following steps (A) and (B) is performed at least once. Step (A): a step including a chloride deposition step (a1) for depositing chlorides on the metal material in an atmosphere having a relative humidity Ha1 of 80% or higher and a temperature Ta1 of 60°C or lower. Step (B): a step in which a cycle having a predetermined drying step (b1), a predetermined wetting step (b2), a predetermined transition step (b3), and a predetermined transition step (b4) is performed at least once.
Disclosed is an Fe-based electroplated steel sheet including: a Si-containing cold-rolled steel sheet containing Si in an amount of 0.1 mass % or more and 3.0 mass % or less; and an Fe-based electroplating layer formed on at least one surface of the Si-containing cold-rolled steel sheet with a coating weight per surface of 5.0 g/m2 or more, in which in an intensity profile measured by glow discharge optical emission spectrometry, a peak of emission intensity at wavelengths indicating Si is detected within a range from a surface of the Fe-based electroplating layer to more than 0.2 μm in a thickness direction and not more than a thickness of the Fe-based electroplating layer, and an average value of C concentration in a region ranging from 10 μm to 20 μm in the thickness direction from the surface of the Fe-based electroplating layer is 0.10 mass % or less.
To directly and clearly observe the state inside a melting chamber in an electric furnace, a video-device-equipped electric furnace comprises: a melting chamber; a preheating chamber; and a video device to observe an inside of the melting chamber. The video device includes: a relay lens; an inner tube containing the relay lens and having an outer diameter of 100 mm or less; an outer tube containing the inner tube; and an imaging device located at an axial end of the relay lens on a furnace outside. The video device is provided through a hole in a furnace wall or lid so that the relay lens is located 300 mm to 3500 mm away from a highest molten iron interface in a vertically upward direction and the imaging device is located 300 mm or more away from an inner wall of the furnace wall or lid in a furnace outward direction.
F27B 3/08 - Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces heated electrically, e.g. electric arc furnaces, with or without any other source of heat
20.
LIQUID LEVEL DETECTION METHOD AND DETECTION APPARATUS FOR THE SAME, MOLTEN MATERIAL LIQUID LEVEL DETECTION METHOD AND DETECTION APPARATUS FOR THE SAME, AND METHOD FOR OPERATING VERTICAL FURNACE
A molten material liquid level detection method that can detect a liquid level of molten material from a residual amount of the molten material with high accuracy and a method for operating a vertical furnace by using the detection method. The molten material liquid level detection method detects a liquid level of molten material remaining in a bottom portion of a vertical furnace after end of discharge of a molten material. The molten material liquid level detection method includes calculating a void fraction of the solid-filled structure, and detecting a liquid level of the molten material after the end of the discharge by using the calculated void fraction and a residual amount of the molten material after the end of the discharge.
F27B 1/28 - Arrangements of monitoring devices, of indicators, of alarm devices
F27D 21/00 - Arrangement of monitoring devices; Arrangements of safety devices
G01F 23/22 - Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
21.
METHOD FOR IDENTIFYING PORTION CAUSING INCREASE IN FORMING LOAD, METHOD FOR MANUFACTURING PRESS FORMED PART, DEVICE FOR IDENTIFYING PORTION CAUSING INCREASE IN FORMING LOAD, AND PROGRAM FOR IDENTIFYING PORTION CAUSING INCREASE IN FORMING LOAD
The method for identifying a portion causing an increase in a forming load according to the present invention comprises: step S1 for setting an evaluation region in a press-forming die model 15; step S3 for calculating the forming load distribution of the press-forming die model 15; step S5 for calculating a load evaluation value for each evaluation region; step S7 for changing the deformation resistance of one evaluation region in the press-forming die model, and calculating the load evaluation value of the evaluation region in which the deformation resistance has been changed; and step S9 for identifying an evaluation region in which the load evaluation value varies before and after the deformation resistance change of the press-forming die model, and identifying the portion of a press formed part 1 corresponding to the identified evaluation region as a portion that causes an increase in the forming load.
This method for manufacturing a press-molded article is for manufacturing a press-molded article that includes at least a top plate section, a vertical wall section, and a ridge section that is a portion connecting the top plate section and the vertical wall section. The method comprises: a first molding step in which a metal plate blank is press-molded into an intermediate molded article that includes an intermediate top plate section, an intermediate vertical wall section, and an intermediate ridge section connecting the intermediate top plate section and the intermediate vertical wall section, and that includes, in one or a plurality of locations in the intermediate top plate section including the intermediate ridge section, a protruding section which is higher than the reference height of the top plate surface; and a second molding step in which the intermediate molded article is press-molded into a press-molded article.
A method for generating a cargo handling transport path for transporting suspended cargo suspended from arm tip portion of crane arm from an optional cargo handling initial position to an optional cargo handling target position by swinging movement of the crane arm, and the method includes: calculating the cargo handling transport path and a cargo handling transport velocity for transporting the suspended cargo in a straight line track as viewed from at least the vertical direction in at least a part of the cargo handling transport path based on the cargo handling initial position, the cargo handling target position, the range of the arm minimum swinging circle of the crane arm, the upper limit swinging angular velocity of the crane arm, the upper limit swinging angular acceleration of the crane arm, the upper limit luffing velocity of the crane arm, and the upper limit luffing acceleration of the crane arm.
An abnormality determination model generating device generates an abnormality determination model for determining an abnormality of a facility performing a predetermined operation, and includes: a time-series signal clipping unit configured to clip K times from one or more time-series signals indicating an operation state of the facility during normal operation of the facility; and an abnormality determination model generating unit configured to generate the abnormality determination model from the time-series signals during the normal operation clipped out by the time-series signal clipping unit, wherein the abnormality determination model generating unit is configured to clip L items per one time of clipping from the time-series signals during the normal operation clipped by the time-series signal clipping unit and configures an L-dimensional vector including L variables.
A residual stress distribution calculation method according to the present invention is used to calculate a distribution of residual stress occurring in a metal plate that has been subjected to plastic deformation, and includes: a process (S10) for acquiring a surface deformation history of a deformed part 33 of the metal plate 31 in the course of the deformation causing the plastic deformation of the metal plate 31, and acquiring a strain history and a spin history occurring in the deformed part 33, from the acquired surface deformation history; a process (S20) for successively updating a stress in a material coordinate system at each measurement point set in the deformed part 33 of the metal plate 31, from the start of deformation to the end of deformation in the course of the deformation; and a process (S30) for calculating the residual stress distribution by converting the stress in the material coordinate system at each measurement point at the end of deformation into a stress in a global coordinate system.
Provided is an oriented electromagnetic steel sheet that can effectively inhibit generation of a magnetizing inrush current when used as a material of an iron core for a transformer. In the oriented electromagnetic steel sheet having been subjected to magnetic domain refinement, magnetization changing with a 50 Hz sine wave is generated in a rolling direction of the oriented electromagnetic steel sheet, a power source is shut down when the magnetization reaches 1.50 T, and a residual magnetic flux density Br, which is a magnetic flux density 0.1 s after the shutdown, is 1.00 T or less.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
This surface defect detecting method for optically detecting a surface defect of a strip-shaped body includes an image acquisition step for detecting reflected light from the strip-shaped body, obtained by illuminating a surface of the strip-shaped body, and imaging the surface of the strip-shaped body while scanning relative thereto, to acquire a plurality of images including the surface of the strip-shaped body, an average image calculation step for calculating an average image of the plurality of acquired images, an image correction step for obtaining a corrected image by performing shading correction of each of the plurality of acquired images using the average image, and a defect detection step for detecting a surface defect of the strip-shaped body on the basis of the corrected image, wherein the average image calculation step includes recognizing an inspection target region, of the image, in which the strip-shaped body is present, in each of the plurality of images, and arranging that only pixels in the inspection target region contribute to the average image.
G01N 21/892 - Investigating the presence of flaws, defects or contamination in moving material, e.g. paper, textiles characterised by the flaw, defect or object feature examined
A gutter management system according to the present invention comprises: a measurement device that is arranged above a gutter facing the gutter and measures the inner surface shape of the gutter; and a determination device that determines the wear state of the gutter using at least the measured data of the inner surface shape and a prescribed determination model.
Provided is a welded joint which excels in normal temperature toughness and the matrixes of which are relatively thin and high-strength steel sheets. The thickness of each of the matrix steel sheets is 0.8-10 mm. Among the matrix steel sheets, at least one of the matrix steel sheets has: a steel structure in which the total surface area proportion of martensite and bainite is greater than 50%; and a tensile strength of at least 980 MPa. The oxygen amount and the Vicker's hardness of the welded metal of a weld satisfy a prescribed relationship.
Provided are: continuous annealing equipment capable of swiftly responding to a fluctuation in material characteristics and minimizing a fluctuation in mechanical characteristics of a product; a continuous annealing method; a cold-rolled steel sheet manufacturing method; and a plated steel sheet manufacturing method. The continuous annealing equipment is for a steel sheet and is provided with a heating zone (6), a soaking zone (7), and a cooling zone (8) in this order, said continuous annealing equipment comprising: at least one induction heating device (9) which is provided between the soaking zone (7) and the cooling zone (8); and a measurement device (transformation ratio meter 10) which measures at least one steel sheet phase fraction at or after an outlet of the induction heating device (9).
Provided is a resistance spot welding method suited for manufacturing a welded joint that exhibits superior delayed fracture resistance. In the resistance spot welding method, two or more superimposed steel plates are sandwiched between a pair of welding electrodes and energized while being pressurized to form a nugget on the superimposed surfaces of the steel plates, and the steel plates are thereby bonded, the resistance spot welding method being characterized in that, after the bonding, a steady magnetic field is applied to a weld mark generated on the surface of the bonded steel plates through the bonding such that the magnetic flux density becomes 0.1-15 T at an angle θ, formed by a surface normal direction of the bonded steel plates and the application direction of the steady magnetic field, exceeding 0°.
22) and chlorine ions (Cl-25050 particle diameter, which is the median diameter located at the 50th percentile of the mass cumulative distribution, of 10-200 μm, and an apparent density of 3.5-5.0 mg/m3.
Provided are: a steel sheet having high strength, excellent in terms of ductility and hole expansibility, and having highly stable mechanical properties along the sheet width direction; a member; and methods for producing the steel sheet and the member. The steel sheet has a composition containing, in terms of mass%, 0.08-0.35% C, 0.4-3.0% Si, 1.5-3.5% Mn, up to 0.02% P, up to 0.01% S, up to 1.0% sol. Al, and up to 0.015% N, the remainder comprising Fe and unavoidable impurities, and has a steel structure in which the areal content of ferrite is 5% or less (including 0%), the total areal content of tempered martensite and lower bainite is 70% or higher, the volume content of retained austenite is 5-15%, and the areal content of fresh martensite is 10% or less (including 0%). The steel sheet has a standard deviation of sheet-width-direction total elongation (EL) of 0.9% or less.
Provided are: a steel sheet having high strength, excellent in terms of ductility and hole expansibility, and having highly stable mechanical properties along the longitudinal direction of the coil; and a method for producing the steel sheet. The steel sheet has a composition containing, in terms of mass%, 0.08-0.35% C, 0.4-3.0% Si, 1.5-3.5% Mn, up to 0.02% P, up to 0.01% S, up to 1.0% sol. Al, and up to 0.015% N, the remainder comprising Fe and unavoidable impurities, and has a steel structure in which the areal content of ferrite is 5% or less (including 0%), the total areal content of tempered martensite and lower bainite is 70% or higher, the volume content of retained austenite is 5-15%, and the areal content of fresh martensite is 10% or less (including 0%). The steel sheet has a standard deviation of coil-longitudinal-direction tensile strength (TS) of 30 MPa or less.
This calculation method is used for manufacturing or using a product, and comprises: a step (S2) for calculating a feature amount by using one or more input values selected from a predetermined input value group and one or more first models; and a step (S3) for calculating a deviation amount which is a deviation from each of the first models with respect to the predetermined input value from the input value group, by using one or more input values selected from the input value group and one or more second models. The second models and the first models are machine learning models generated by using one or more teacher data items each selected from a predetermined teacher data group.
STEEL TUBE EXHIBITING EXCELLENT FATIGUE CHARACTERISTICS AGAINST HYDROGEN AND PRODUCTION METHOD THEREFOR, AND STEEL MATERIAL AND PRODUCTION METHOD THEREFOR
The purpose of the present invention is to provide a steel tube and a production method therefor, the steel tube being suitable for steel structures used in high pressure hydrogen gas environments, such as line pipes for 100% hydrogen gas or natural gas including hydrogen gas with a hydrogen partial pressure of 1 MPa or more (natural gas is gas having a hydrocarbon such as methane or ethane as the main component), and also exhibiting excellent fatigue characteristics in a high pressure hydrogen gas environment; and to provide a steel material and a production method therefor. This steel tube exhibits excellent fatigue characteristics in hydrogen and has a specific component composition and a specific structure, a crack growth rate da/dN of 1.0×10-6m·cycle-1 or less when the stress intensity factor range in hydrogen of 1 MPa or more is 20 MPa√m.
B21B 17/00 - Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
C21D 8/02 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
C21D 8/10 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
C21D 9/08 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
B22D 11/00 - Continuous casting of metals, i.e. casting in indefinite lengths
38.
LINE PIPE STEEL MATERIAL HAVING EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE, MANUFACTURING METHOD THEREFOR, LINE PIPE STEEL TUBE HAVING EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE, AND MANUFACTURING METHOD THEREFOR
The purpose of the present invention is to provide a line pipe steel material that is suitable for use in a steel structure used in a high-pressure hydrogen gas environment, such as a line pipe for 100% hydrogen gas or a natural gas (natural gas being a gas having a hydrocarbon such as methane or ethane as a primary component) containing hydrogen having a hydrogen partial pressure of at least 1 MPa, and that has high strength and excellent hydrogen embrittlement resistance in a high-pressure hydrogen gas environment. The purpose of the present invention is also to provide a manufacturing method therefor, as well as a line pipe steel tube and a manufacturing method therefor. Provided is a line pipe steel material having excellent hydrogen embrittlement resistance that has a specific chemical composition and a specific structure, wherein the fatigue limit stress in hydrogen that is at 1 MPa or higher is at least 200 MPa, and the ratio of the fatigue limit stress in hydrogen that is at 1 MPa or higher to the fatigue limit stress in an inert gas environment is at least 0.90.
A high-strength cold-rolled steel sheet has a chemical composition containing C: 0.150 to 0.350 mass %, Si: 0.80 to 3.00 mass %, Mn: 1.50 to 3.50 mass %, P: 0.100 mass % or less, S: 0.0200 mass % or less, Al: 0.100 mass % or less, N: 0.0100 mass % or less, and O: 0.0100 mass % or less, with a remaining part consisting of Fe and impurities. The amount of diffusible hydrogen is 0.50 mass ppm or less, the area ratio of tempered martensite and bainite is 55 to 95%, the area ratio of retained austenite is 5 to 30%, a prior austenite grain has an average circle equivalent diameter of 15.0 μm or less, and the ratio b/a is 0.80 or less, where a circumferential length of the prior austenite grain is a, and a circumferential length of a portion of the prior austenite grain having a carbon concentration of 0.6 mass % or more is b.
The present invention relates to a method for manufacturing a press-formed product 1 that is curved in top view and has at least a top plate part 3 and a vertical wall part 5 continuous from the top plate part 3, the method reducing an error from a target shape due to springback of the press-formed product 1 after being released from a die. The method comprises: a forming step for performing press-forming using a forming die provided with a first prospective angle that introduces a torsion (reverse torsion) due to springback in a reverse direction to a torsion (normal torsion) that would be caused by springback if the press-forming were performed in a single step without providing the die with the prospective angle; and a restriking step for press-forming a formed product 17 formed in the forming step, using a restrike die provided with a second prospective angle for reducing the reverse torsion.
Provided is a casting mold that enables a temperature detection interval to be shortened without having to execute specialized processing of a slit groove. A casting mold 12 is used in continuous casting of steel. The casting mold 12 includes a plurality of casting-mold copper sheets. At least one of the plurality of casting-mold copper sheets includes optical fiber-type temperature sensors 50 embedded in locations in at least two tiers which differ in the casting direction and embedded so as to extend in the width direction of the casting-mold copper sheet.
Provided is a weld joint having relatively thin high-strength steel plates as a base material and excellent room-temperature fracture toughness. In the present invention, the plate thickness of the base-material steel plates is 0.8-10 mm, at least one of the base-material steel plates has a tensile strength of at least 980 MPa and a steel structure in which the total area fraction of martensite and bainite is more than 50%, and the amount of oxygen in the welded metal in welded sections and the total area fraction of the martensite and bainite in the welded metal satisfy a prescribed relationship.
In order to efficiently confirm joining of threaded joints on pipes, the present invention provides a clearance measuring method, for a pair of threaded joints having a male joint and a female joint corresponding to the male joint, for measuring the clearance between the thread of the male joint and the thread of the female joint. The clearance measuring method includes: a joining completed state setting step for setting a joining completed state in which joining of the male joint and the female joint is completed, on the basis of data on thread shapes of the male joint and the female joint; a clearance measuring step for measuring, in the joining completed state, the clearance between the thread of the male joint and the thread of the female joint corresponding to the thread of the male joint; and a rotated state setting step for setting a state in which rotation is made by a predetermined angle in such a direction as to enjoining the joining, if the joining of the male joint and the female joint is not an unjoined state after the clearance measuring step. The steps from the clearance measuring step to the rotated state setting step are repeatedly executed until the joining is unjoined.
G01B 21/16 - Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring distance or clearance between spaced objects
F16L 15/00 - Screw-threaded joints; Forms of screw-threads for such joints
G01B 21/20 - Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring contours or curvatures, e.g. determining profile
44.
CONTINUOUS ANNEALING FACILITY, CONTINUOUS ANNEALING METHOD, METHOD FOR PRODUCING COLD-ROLLED STEEL SHEET, AND METHOD FOR PRODUCING PLATED STEEL SHEET
Provided are: a continuous annealing facility in which a steel sheet phase fraction under a high-temperature condition is predicted with high accuracy and the fluctuations in the predicted phase fraction is rapidly reflected in an annealing condition; a continuous annealing method; a method for producing a cold-rolled steel sheet; and a method for producing a plated steel sheet. The continuous annealing facility is a continuous annealing facility for steel sheets, and is provided with a heating zone (6), a soaking zone (7) and a cooling zone (8) in this order, in which at least one induction heating device (9) and a control device that presets the conditions for operation of the induction heating device on the basis of the phase fraction during annealing which has been acquired by a phase fraction prediction model are provided between the soaking zone (7) and the cooling zone (8).
Provided are a high aging-efficiency maraging steel and a method for producing the same. The maraging steel comprises: a component composition that includes, in mass%, C at 0.02% or less, Si at 0.1% or less, Mn at 0.1% or less, P at 0.01% or less, S at 0.01% or less, N at 0.01% or less, Ni at 12-25%, Co at 5-12%, Mo at 2-7%, Ti at 0.5-1.5%, and Al at 0.01-0.1%, with the balance made up of iron and inevitable impurities; and a steel structure having a transformed martensitic phase at an area ratio of 90% or more.
C21D 9/00 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
C22C 38/14 - Ferrous alloys, e.g. steel alloys containing titanium or zirconium
46.
STEEL PIPE FOR LINE PIPE HAVING EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE CHARACTERISTICS, METHOD OF MANUFACTURING SAME, STEEL MATERIAL FOR LINE PIPE, AND METHOD OF MANUFACTURING SAME
The purpose of the present invention is to provide a steel pipe for a line pipe and a method of manufacturing the same, and a steel material for a line pipe and a method of manufacturing the same, the steel pipe for a line pipe being suitable for steel structures that are used in a high-pressure hydrogen gas environment, such as a line pipe for 100% hydrogen gas or natural gas containing hydrogen with a hydrogen partial pressure of more than or equal to 1 MPa (natural gas is a gas having hydrocarbon, such as methane or ethane, as a major component), the steel pipe for a line pipe having high strength and excellent hydrogen embrittlement resistance characteristics in a high-pressure hydrogen gas environment. The steel pipe for a line pipe is characterized by having excellent hydrogen embrittlement resistance characteristics and a specific component composition and a specific structure, wherein the fatigue limit stress in hydrogen of more than or equal to 1 MPa is more than or equal to 200 MPa, and the value of the fatigue limit stress in hydrogen of more than or equal to 1 MPa over the fatigue limit stress in an inert gas environment is more than or equal to 0.90.
B21B 17/00 - Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
C21D 8/00 - Modifying the physical properties by deformation combined with, or followed by, heat treatment
C21D 8/10 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
C21D 9/08 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
The purpose of the present invention is to provide: a steel material which has excellent fatigue characteristics in a high-pressure hydrogen gas environment and is suitable for use in a steel structure, which is used in the high-pressure hydrogen gas environment, such as a line pipe for 100% hydrogen gas or natural gas (which is gas mainly composed of hydrocarbons such as methane and ethane) that contains hydrogen having a hydrogen partial pressure of 1 MPa or more; a method for producing the steel material; a steel pipe; and a method for manufacturing the steel pipe. The steel material has a specific component composition and a specific structure, and has excellent fatigue characteristics in hydrogen, wherein the crack growth rate da/dN at a stress intensity factor (= 20 MPa√m) in hydrogen of at least 1 MPa is at most 1.0×10-6m·cycle-1.
The purpose of the present invention is to provide: a steel material for line pipes and a production method therefor, the steel material for line pipes being suitable for steel structures used in high pressure hydrogen gas environments, such as line pipes for 100% hydrogen gas or natural gas including hydrogen gas with a hydrogen partial pressure of 1 MPa or more (natural gas is gas having a hydrocarbon such as methane or ethane as the main component), and having high strength and an excellent hydrogen embrittlement resistant property against a high pressure hydrogen gas environments; and a steel tube for line pipes and a production method therefor. The steel material for line pipes has a specific chemical composition, and has an area fraction of retained austenite of 0-3%, a hydrogen diffusion coefficient at room temperature of 1.5×10-10m2/s or more, and a hydrogen solid solubility of 0.05 mass ppm/√P or less.
C21D 8/02 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
C21D 8/10 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
49.
HIGH-STRENGTH LINE PIPE STEEL MATERIAL HAVING EXCELLENT FRACTURE TOUGHNESS IN HYDROGEN, METHOD FOR MANUFACTURING SAME, STEEL TUBE FOR HIGH-STRENGTH LINE PIPES, AND METHOD FOR MANUFACTURING SAME
A cooling water temperature control method, includes: calculating thickness of a water film remaining on a steel sheet; calculating a change in the thickness of the water film; calculating a change in temperature of the steel sheet; calculating a steel sheet temperature on an exit side of a draining roll at which a position where the thickness of the water film on the steel sheet becomes zero coincides with an exit side position of a drying equipment, and setting the calculated temperature to a lower limit value; calculating a steel sheet temperature on the exit side of the draining roll at which the steel sheet temperature on the entrance side of coating equipment coincides with a predetermined temperature and setting the calculated temperature to an upper limit value; and controlling the temperature of cooling water within a range of the lower limit value and the upper limit value.
A method for forming a film on a surface of a steel sheet includes applying a treatment solution for forming a film containing a fibrous material to the surface of the steel sheet by using a coater under a condition in which a difference between a speed of the steel sheet and a speed of an applicator of the coater is 1.0 m/min or more, inclining the surface of the steel sheet, to which the treatment solution for forming a film has been applied, at an angle of 10° or more with respect to a horizontal plane until drying is started, and thereafter drying the steel sheet.
H01F 41/00 - Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
C22C 38/02 - Ferrous alloys, e.g. steel alloys containing silicon
C22C 38/04 - Ferrous alloys, e.g. steel alloys containing manganese
C22C 38/06 - Ferrous alloys, e.g. steel alloys containing aluminium
C22C 38/16 - Ferrous alloys, e.g. steel alloys containing copper
C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
C23C 22/07 - Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH < 6 containing phosphates
An electrical steel sheet with an insulating film, the steel sheet having an insulating film containing a crystalline fibrous material on a surface of the steel sheet, in which a ratio (LRD/LTD) of a length in a rolling direction (LRD) of the crystalline fibrous material in a cross section in the rolling direction of the insulating film to a length in a direction perpendicular to the rolling direction (LTD) of the crystalline fibrous material in a cross section in the direction perpendicular to the rolling direction of the insulating film is 1.5 or more and 50.0 or less.
B05D 1/28 - Processes for applying liquids or other fluent materials performed by transfer from the surfaces of elements carrying the liquid or other fluent material, e.g. brushes, pads, rollers
53.
WARPED METAL BELT SHAPE ESTIMATION METHOD, METAL BELT ACCEPTANCE DETERMINATION METHOD, METAL BELT MANUFACTURING METHOD, AND WARPED METAL BELT SHAPE ESTIMATION FACILITY
Provided are a warped metal belt shape estimation method, a metal belt acceptance determination method, and a warped metal belt shape estimation device which can estimate a warped shape in a plate width direction in a state where the tension is unloaded, from the warped shape in the plate width direction in a state where the tension in a longitudinal direction is loaded onto the warped shape in the plate width direction generated by rapid cooling of the metal belt. This warped metal belt shape estimation method estimates the warped shape in the plate width direction of the metal belt in an un-tensioned state where the tension is unloaded, from the shape in the plate width direction of the metal belt in a tensioned state where the tension in the longitudinal direction is loaded, wherein the method comprises: a plate width direction shape measurement step for measuring a plate width direction shape distribution of the metal belt in the tensioned state; an approximate curve calculation step for calculating the plate width direction shape distribution, which is measured in the plate width direction shape measurement step, as an approximate curve approximated by a quadratic curve or a circular arc; and a warped shape estimation step for using the plate width direction shape distribution and the approximate curve to estimate the warped shape in the plate width direction of the metal belt in the unloaded state.
A press forming fracture determination method according to the present invention involves: (P1) acquiring a metal plate forming limit expressed as a relationship between a maximum principal strain and a minimum principal strain of a test piece 100 stretch-formed using various degrees of bending deformation, and the degree of bending deformation; and (P3) determining the presence or absence of fracture generation in the press formed part on the basis of the acquired metal plate forming limit, the maximum principal strain and the minimum principal strain calculated for the press formed part, and the degree of bending deformation.
Provided are: a water content measurement method capable of reliably measuring a water content of a measured object, even when a layer thickness of the measured object fluctuates; a water content measurement device; and a manufacturing method for coke. The water content measurement method includes: a microwave measurement step of, when transmitted microwaves are transmitted to a measured object S by a microwave transmission unit 11 that moves relative to the measured object S, receiving, by using a microwave reception unit 12, the transmitted microwaves that have passed through the measured object S as received microwaves, and finding the attenuation thereof and the phase difference between the transmitted microwaves and the received microwaves; a bulk density calculation step of calculating an amount of the measured object S, a movement speed of the measured object S relative to the microwave transmission unit 11, and the bulk density of the measured object S on the basis of the layer thicknesses of the measured object S; and a water content calculation step of calculating a water content of the measured object S using the phase difference, the attenuation, and the bulk density measured by a microwave evaluation unit 13.
G01N 9/36 - Analysing materials by measuring the density or specific gravity, e.g. determining quantity of moisture
G01N 22/00 - Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
58.
BULK DENSITY DETECTION METHOD AND DEVICE, WATER CONTENT CALCULATION METHOD AND DEVICE, AND METHOD FOR PRODUCING COKE
Provided are a bulk density detection method and device, a water content calculation method and device, and a method of producing coke that enable highly accurate detection of bulk density without needing to use a special device. This bulk density detection method is for emitting microwaves at an object and detecting the bulk density of the object, said method comprising: a microwave emission step for emitting emission microwaves of each of a plurality of wavelengths at the object; a microwave receiving step for receiving the emission microwaves, having been transmitted through the object, as reception microwaves for each of the plurality of wavelengths; an attenuation amount calculation step for calculating, for each of the plurality of wavelengths, an attenuation amount that is the difference in energy between the emission microwaves and the reception microwaves; a wavelength identification step for extracting a wavelength distribution of the attenuation amounts that is based on a predetermined regular wavelength distribution, with regard to the relationship between the calculated attenuation amounts and the wavelengths corresponding to the attenuation amounts, and also identifying, in the wavelength distribution, a predetermined representative wavelength included in the regular wavelength distribution; and a bulk density detection step for detecting the bulk density of the object on the basis of the identified representative wavelength.
G01N 22/00 - Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
C10B 57/04 - Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition
G01N 9/24 - Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing the transmission of wave or particle radiation through the material
A steel sheet having a film containing an organic resin and a wax on at least one surface of the steel sheet, in which the organic resin is at least one of an acryl-based resin, an epoxy-based resin, a urethane-based resin, a phenol-based resin, a vinyl acetate-based resin, and a polyester-based resin, in which the wax is a polyolefin wax having a melting temperature of 120° C. or higher and 140° C. or lower and an average particle size of 3.0 μm or less, in which a proportion of the wax in the film is 10 mass % or more, and in which a coating weight per side W (g/m2) of the film and an arithmetic average roughness Ra (μm) of the steel sheet satisfy relational expression (1) below.
A steel sheet having a film containing an organic resin and a wax on at least one surface of the steel sheet, in which the organic resin is at least one of an acryl-based resin, an epoxy-based resin, a urethane-based resin, a phenol-based resin, a vinyl acetate-based resin, and a polyester-based resin, in which the wax is a polyolefin wax having a melting temperature of 120° C. or higher and 140° C. or lower and an average particle size of 3.0 μm or less, in which a proportion of the wax in the film is 10 mass % or more, and in which a coating weight per side W (g/m2) of the film and an arithmetic average roughness Ra (μm) of the steel sheet satisfy relational expression (1) below.
W≥0.12×Ra2+0.2 (1)
C10M 111/04 - Lubricating compositions characterised by the base-material being a mixture of two or more compounds covered by more than one of the main groups , each of these compounds being essential at least one of them being a macromolecular organic compound
C10M 107/26 - Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing monomers having an unsaturated radical bound to an acyloxy radical of a saturated carboxylic or carbonic acid
C10M 107/28 - Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing monomers having an unsaturated radical bound to a carboxyl radical, e.g. acrylate
To clearly observe the inside of a furnace where an object is heated by a burner. The burner includes: a lens; an imaging device; and a multiple pipe structure including: an inner pipe that surrounds the lens; an outer pipe that surrounds the inner pipe, separated from the inner pipe by a lens coolant passage; a gaseous fuel pipe radially outward of the outer pipe and operable to inject gaseous fuel; a combustion-supporting gas pipe radially outward of the outer pipe and operable to inject combustion-supporting gas; and a cooling pipe outermost in the multiple pipe structure that surrounds the gaseous fuel pipe and the combustion-supporting gas pipe.
F27B 3/08 - Hearth-type furnaces, e.g. of reverberatory type; Electric arc furnaces heated electrically, e.g. electric arc furnaces, with or without any other source of heat
G02B 27/00 - Optical systems or apparatus not provided for by any of the groups ,
61.
STEEL PLATE LIFTING METHOD WITH USE OF LIFTING MAGNET, LIFTING MAGNET, AND METHOD FOR MANUFACTURING STEEL PLATE BY USING LIFTING MAGNET
A method for using a lifting magnet and a lifting magnet. The lifting magnet includes a plurality of electromagnet coils that are each independently ON/OFF-controllable and voltage-controllable, and a magnetic pole that is excited by application of a voltage to the electromagnet coils. An electromagnet coil to be used for lifting steel plates is determined based on a total thickness of the steel plates to be lifted. An amount of passing magnetic flux Φr in the magnetic pole in a case where magnetic flux passes through only the steel plates to be lifted when the electromagnet coil is used is calculated. An application voltage to be applied to the electromagnet coil used for lifting the steel plates is determined based on the amount of passing magnetic flux Φr. The application voltage is applied to the electromagnet coil.
In a production of a grain-oriented electrical steel sheet comprising hot rolling a raw steel material, cold rolling, decarburization annealing, applying an annealing separator composed mainly of MgO, finish annealing and magnetic domain subdividing, the annealing separator including certain compounds, and the finish annealing conducted by holding the steel sheet at a temperature of 800 to 950° C. for 10 to 100 hours and passing a dry gas containing not less than 1 vol % of H2 and having a dew point of not higher than 10° C. to reach a furnace pressure of not less than 3.5 mmH2O from not lower than 1050° C. to a purification treatment temperature, so that a pickling weight loss of undercoat film by pickling with HCl is not more than 1.8 g/m2 and the total concentration of Sn, Sb, Mo, and W on a boundary face between the film and iron matrix is 0.01 to 0.15 mass %.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
Provided is a low-yield-ratio hot-rolled steel sheet having excellent strength and low-temperature toughness. The steel sheet has a predetermined component composition. The steel structure of the sheet thickness center part has a main phase, which is ferrite, and a second phase in which the total area ratio of pearlite and pseudopearlite is 6-25% and the area ratio of upper bainite is 5% or less. When a region surrounded by boundaries where the orientation difference between adjacent crystals is 15° or more is taken as a crystal grain, the average crystal grain size of the steel structure containing the main phase and the second phase in the sheet thickness center part is 10.0-30.0 μm, the area ratio of crystal grains having a crystal grain size within this average crystal grain size±5.0 μm is 35% or more, and the number of crystal grains in which the ratio (major axis)/(minor axis) of the major axis to the minor axis is 3.0 or more is 30/mm2 or fewer.
B21B 1/22 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length
B21C 37/08 - Making tubes with welded or soldered seams
B21C 37/15 - Making tubes of special shape; Making the fittings
C21D 8/02 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
C21D 9/08 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
C21D 9/50 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for welded joints
64.
METHOD FOR PRODUCING HOT METAL USING SOLID REDUCING FURNACE AND SUBMERGED ARC FURNACE
Provided is a method for producing a hot metal, whereby it becomes possible to achieve high energy efficiency in a melting step when reduced iron is produced from iron ore in a solid reducing furnace and then the reduced iron is melted in a SAF to produce a hot metal. The method for producing a hot metal according to the present invention comprises a step for producing first reduced iron from low-grade iron ore pellets, an optional step for producing second reduced iron from high-grade iron ore pellets, an optional step for producing third reduced iron from lump ore, an optional step for preparing fourth reduced iron, and a step for melting the first reduced iron to fourth reduced iron in a SAF and adding a slag-making material to the resultant product for basicity adjustment purpose, in which the following formula is satisfied. 150.0 ≤ S1×W1+S2×W2+S3 ≤ 400.0, in which S1: the slug ratio of the first reduced iron, W1: the blend ratio of the first reduced iron, S2: the average slug ratio of the second reduced iron to fourth reduced iron, W2: the total blend ratio of the second reduced iron to fourth reduced iron, and S3: the amount of the slag-making material to be added in the melting step.
Provided is a method that is for controlling a warp shape of a metallic band, and that makes it possible to reduce the height of warp in a metallic band on the downstream side of a temper rolling mill by performing control on a warp shape having a W-shaped cross section in the plate width direction or on a warp shape that is approximated by a high-dimensional function. The method for controlling the warp shape of a metallic band is for use in a metallic band manufacturing facility comprising a temper rolling mill 31 for correcting the shape of a metallic band 1 conveyed continuously and a warp shape measurement device for measuring the warp shape of the metallic band, and controls an exit-side warp which is the warp shape of the metallic band 1 on the downstream side of the temper rolling mill 31. The method involves: calculating an approximate curve for the warp shape of the metallic band 1 using an approximation method selected from among parabola approximation, circular arc approximation, and envelope approximation; and setting, on the basis of the calculated approximate curve, operational parameters, for the temper rolling mill 31, capable of reducing the warp height in the exit-side warp shape.
B21B 37/28 - Control of flatness or profile during rolling of strip, sheets or plates
B21B 1/22 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length
B21B 37/38 - Control of flatness or profile during rolling of strip, sheets or plates using roll bending
B21B 38/02 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring flatness or profile of strips
B21C 51/00 - Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses
METHOD OF PREDICTING FORM OF WARPING IN METAL STRIP, METHOD OF CONTROLLING FORM OF WARPING IN METAL STRIP, METHOD OF MANUFACTURING METAL STRIP, METHOD OF GENERATING WARPING-FORM PREDICTION MODEL, AND DEVICE FOR CONTROLLING FORM OF WARPING IN METAL STRIP
Provided, for metal-strip continuous-annealing lines that include a cooling zone where metal-strip cooling is carried out and a temper mill in which post-cooling metal-strip form rectification is carried out, is a method of predicting metal-strip warping form, in which the form of metal-strip warping on the entry-side is taken into consideration to enable quick prediction of the form of warping on the exit side. This method of predicting metal-strip warping form is for predicting an exit-side warping form, which is the form of warping in metal strip 1 along the downstream side of a temper mill 40 in a metal-strip continuous-annealing line that includes: heating equipment for heating metal strip; cooling equipment 30 for cooling metal strip 1 that has been heated in a heating zone; the temper mill 40 for rectifying the form of the metal strip 1 that has been cooled with the cooling equipment; and an entry-side warping form measuring device 16 for measuring, between the cooling equipment 30 and the temper mill 40, an entry-side warping form, which is the form of warping in the metal strip along the upstream side of the temper mill. The form of warping on the exit side is predicted on the basis of: the form of warping on the entry side; and at least one among parameters of operation of the temper mill 40.
B21B 37/28 - Control of flatness or profile during rolling of strip, sheets or plates
B21B 1/22 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length
B21B 37/00 - Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
B21B 37/74 - Temperature control, e.g. by cooling or heating the rolls or the product
B21B 38/02 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring flatness or profile of strips
B21C 51/00 - Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses
C21D 9/52 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for strips
The purpose of the present invention is to provide a welded member and a method for manufacturing the same. The present invention relates to a welded member in which a sheet set obtained by stacking two or more steel sheets is welded together through resistance spot welding, wherein: the average value of the shortest distance from the center of a welding point to the end surface of the steel sheet is 3.0 mm or greater; if there are a plurality of welding points, then the average distance between the centers of adjacent welding points is 6.0 mm or greater; at least one of the two or more steel sheets has a decarbonated layer on a steel-sheet obverse layer; and, on the steel sheet having the decarbonated layer, the thickness of the decarbonated layer between a base-material part and a welding-heat-affected part satisfies formula (1). (1): tw/tb < 1.0
To reduce production costs by increasing molten iron heating efficiency, a production method using an electric furnace is provided with a preheating chamber, a melting chamber, a cold iron source supporter operable to partition the preheating chamber into a first and a second preheating chamber, an extruder, and a video device operable to observe the second preheating chamber is used, the method including a melting process, a heating process, a preheating process, and a tapping process are performed. In the heating process, heating of the molten iron is started after the cold iron source supporter is closed, and based on the visual information obtained via the video device of the second preheating chamber.
A crash energy absorption part for an automobile is provided in a front portion or a rear portion of an automotive body and absorbing crash energy when a crash load is input from a front or a rear of the automotive body, and includes: a top portion; a tubular member including a side wall portion continuous with the top portion via a shoulder part of a punch; and a resin applied or patched to at least an inner surface of the shoulder part of a punch of the tubular member. The resin has a thickness gradually changing in an axial direction from one end side toward other end side, a thickest portion of the thickness is 8 mm or less, and the resin is bonded to the inner surface with an adhesive strength of 10 MPa or more and is axially crushed when the crash load is input.
B62D 21/15 - Understructures, i.e. chassis frame on which a vehicle body may be mounted having impact absorbing means, e.g. a frame designed to permanently or temporarily change shape or dimension upon impact with another body
B60R 19/34 - Arrangements for mounting bumpers on vehicles comprising yieldable mounting means destroyed upon impact, e.g. one-shot type
71.
STEEL SHEET, MEMBER, AND METHODS FOR PRODUCING SAME
The present invention provides a carbonaceous material which is used for the production of a sintered ore, and is capable of preventing troubles in the exhaust gas system caused by exhaust gas processing, the troubles including, for example, the generation of tar in pipes and the occurrence of white smoke in an electric dust collector. This carbonaceous material is a solid fuel for the production of a sintered ore, and has an electrical conductivity of 1.0 × 10-9S/m or more and a volatile content (VM) of 15% or less. In cases where this carbonaceous material is composed of a plurality of kinds of carbonaceous materials, 80% or more of the plurality of kinds of carbonaceous materials have an electrical conductivity of 1.0 × 10-9 S/m or more at 80°C to 200°C, and the weighted average of the volatile contents (VM) is 15% or less.
Provided is a method for recovering nickel, cobalt, and manganese from a compound including metal oxides of nickel, cobalt, and manganese in which the concentration of manganese in recovered materials is kept low while increasing the concentrations of nickel and cobalt. The method for recovering nickel, cobalt, and manganese includes: a mixing step in which a reducing agent and a compound containing metal oxides of nickel, metal oxides of cobalt, and metal oxides of manganese are mixed and a mixture is produced; and a heating step in which the mixture is heated to obtain a first product and a second product having a higher concentration of manganese than the first product. In the mixing step, one or more substances selected from among carbon reducing agents containing carbon as a component thereof, silicon reducing agents containing silicon as a component thereof, and aluminum reducing agents containing aluminum as a component thereof are used as the reducing agent, and the reducing agent is used in an amount satisfying a predetermined range.
When a steel slab containing, in mass%, 0.0050% or less of C, 2.0-5.0% of Si, 0.2-1.8% of Mn, 0.5-2.5% of Al, 0.001-0.100% of Mo, and 0.02-0.10% in total of Sn and Sb, the contents of Si, Al and Mn satisfying a predetermined relationship, is hot-rolled, hot roll-annealed, cold-rolled, and finish annealed to manufacture a non-oriented electromagnetic steel plate, the soaking temperature in the finish annealing is set to 500°C or higher and below a temperature T determined from the contents of Si, Al and Mn, the time to maintain the soaking temperature is set to 60 seconds or less, and the residence time at 500°C or higher is set to 100 seconds or less to yield a tensile strength of 700-950 MPa and a dislocation density at the center of the plate thickness of at least 1.2×1014m-2, thereby providing a non-oriented electromagnetic steel plate having high strength after finish annealing and having low core loss after strain relief annealing.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
A meandering amount arithmetically operating device of a meandering amount measurement device calculates the meandering amount of a steel sheet using a drive side edge site zds(N) and a work side edge sites zws(N) at a current time when a measurement reliability determination unit determines that both the drive side edge site zds(N) and the work side edge sites zws(N) at the current time have high reliability. When only one of the drive side edge site zds(N) and the work side edge site zws(N) at the current time is determined to have high reliability, the other edge site is calculated by interpolation using the number of pixels W from a sheet width updating unit with the drive side edge sites zds(N) or the work side edge site zws(N) at the current time having high reliability as a reference.
B21B 38/04 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring thickness, width, diameter or other transverse dimensions of the product
B21C 51/00 - Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses
77.
COLD ROLLING MILL ROLLING CONDITION CALCULATION METHOD, COLD ROLLING MILL ROLLING CONDITION CALCULATION DEVICE, COLD ROLLING METHOD, COLD ROLLING MILL, AND STEEL SHEET MANUFACTURING METHOD
A cold rolling mill rolling condition calculation method includes: an estimation step of estimating a rolling constraint condition with respect to a target steady rolling condition of a roll target material, by inputting second multi-dimensional data to a prediction model, the prediction model having been trained with explanatory variable and response variable, the explanatory variable being first multi-dimensional data generated based on non-steady rolling performance data, among past rolling performance in rolling a roll material by a cold rolling mill, and the response variable being steady rolling performance data and rolling constraint condition data during steady rolling, and the second multi-dimensional data having been generated based on non-steady rolling performance data of the roll target material; and a change step of changing the target steady rolling condition so that the estimated rolling constraint condition satisfies a predetermined condition.
Provided are: a steel sheet and a member that have tensile strength of at least 780 MPa, excellent press-moldability, ductility, and expansion flange moldability, and excellent material stability in a sheet width direction; and a method of manufacturing the steel sheet and the member. The present invention has a component composition and a steel structure with prescribed ranges. The combined surface modulus of quenched martensite and residual austenite with an aspect ratio of 3 or less and a circle-equivalent diameter of at least 2.0 μm, with respect to the total surface modulus of quenched martensite and residual austenite, is 20% or less. The surface modulus of a carbon-concentrated region where the carbon concentration is at least 0.5% by mass is 20% or less with respect to the entire structure.
Provided is a method for producing an iron ore pellet, whereby it is possible to obtain a high-strength green pellet in which bursting can be suppressed. This method for producing an iron ore pellet is characterized by having a step for mixing a binder and iron ore having a total Fe content of 63% by mass to obtain a mixture, a step for granulating the mixture to obtain a green pellet, and a step for firing the green pellet to obtain an iron ore pellet, the iron ore having a core ore 10 having a grain size of more than 1 mm, and a fine ore 12 having a grain size of 1 mm or less.
ENERGY OPERATION ASSISTANCE SYSTEM, INFORMATION PROCESSING DEVICE, DISPLAY TERMINAL DEVICE, ENERGY OPERATION ASSISTANCE METHOD, AND STEEL MILL OPERATION METHOD
2222222 optimization unit. Further, a display terminal device is provided with an information acquisition unit, an information display unit, and an output unit.
To ensure stable supply of a cold iron source to a melting chamber, a method of producing molten iron uses an electric furnace that includes: a preheating chamber; a melting chamber; an extruder located in the preheating chamber; and a video device configured to observe an inside of the melting chamber, and comprises: an extrusion process of supplying a cold iron source preheated in the preheating chamber to the melting chamber by the extruder; and a melting process of melting the cold iron source supplied to the melting chamber by arc heat to obtain molten iron, wherein in the extrusion process, a moving amount of the extruder and/or a time interval for moving the extruder is controlled based on visual information obtained from the video device.
STEEL SHEET, COATED STEEL SHEET, METHOD FOR PRODUCING HOT-ROLLED STEEL SHEET, METHOD FOR PRODUCING COLD-ROLLED FULL HARD STEEL SHEET, METHOD FOR PRODUCING HEAT-TREATED STEEL SHEET, METHOD FOR PRODUCING STEEL SHEET, AND METHOD FOR PRODUCING COATED STEEL SHEET
Disclosed herein are a method for producing a hot-rolled steel sheet, a method for producing a cold-rolled full hard steel sheet, and methods for producing a heat-treated steel sheet that serve as the methods for producing intermediate products for obtaining a steel sheet having a tensile strength of 590 MPa or more, a particular composition and a particular steel structure.
Provided is a high strength electric resistance welded pipe having excellent SSC resistance. This electric resistance welded pipe has an absolute value of residual stress in the circumferential direction of the pipe inner surface of 10 MPa or more and an absolute value of residual shear stress of the pipe inner surface of 300 MPa or less. The steel structure of a base material portion of the electric resistance welded pipe at the center in the thickness direction is configured such that the total of ferrite and bainite is at least 90% in terms of volume ratio, and the average crystal grain diameter is 9.0 μm or less. The steel structure at a position 0.1 mm outside of the pipe inner surface of the base material portion in the pipe radial direction is configured such that the total of ferrite and bainite is at least 95% in terms of volume ratio.
C22C 38/06 - Ferrous alloys, e.g. steel alloys containing aluminium
C22C 38/58 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
B21B 1/22 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length
B21C 37/08 - Making tubes with welded or soldered seams
B21C 37/30 - Finishing tubes, e.g. sizing, burnishing
A method for manufacturing a press-molded article 1 provided with at least a top plate portion 3 having a concave curved portion in a side view and a longitudinal wall portion 7 connecting from the top plate portion 3 through a punch-shoulder-radiused portion 5, the method comprising: a first molding step for press-molding an intermediate molded article 19 having an intermediate top plate portion 21 that curves in the same direction as the top plate portion 3, a step-shaped portion 17 that comprises a step formed continuous with a ridge portion 23 formed in an area corresponding to the punch-shoulder-radiused portion 5, and an outward surface portion 25 that extends outward continuous from the step-shaped portion 17 and curves in the same direction as the intermediate top plate portion 21; and a second molding step for press-molding the intermediate molded article 19 into a press-molded article 1.
Provided is a steel cast slab that contains from 2.0 mass% to less than 7.5 mass% of Ni and has few surface cracks. The steel cast slab containing Ni is composed of, in mass%, C: 0.03% to 0.10%, Si: 0.01% to 0.50%, Mn: 0.10% to 1.00%, P: 0.001% to 0.010%, S: 0.0001% to 0.0050%, Ni: 2.0% to less than 7.5%, Al: 0.010% to 0.080%, N: 0.0010% to 0.0050%, and O: 0.0005% to 0.0040%, with the remainder comprising Fe and unavoidable impurities. The density of solidified nuclei in the surface of the steel cast slab is 0.35/mm2 or more.
Provided is a tundish for continuous casting that enables the purity of molten steel to be increased. This tundish for continuous casting comprises an accommodation section that retains molten steel that has been supplied. The accommodation section comprises: one or more molten steel outflow ports out of which the molten steel is allowed to flow; and a weir that is disposed more to the upstream side of the molten steel than the one or more molten steel outflow ports and that is formed in a hollow cylindrical shape. The weir includes: a base section; a wall section erected from the base section; an eave section disposed so as to cover the peripheral ridge at one end of the wall section and to oppose the base section of the weir; and a gas supply section that supplies an inert gas into an internal space surrounded by the wall section and the base section. The gas supply section includes: a porous section, in the entirety of which a plurality of pores are formed; a support section that supports the porous section and is disposed in the wall section of the weir; and piping that is disposed in the wall section of the weir, between the support section and the base section of the weir, and that discharges the inert gas.
Provided is a tundish for continuous casting that is capable of improving the cleanliness of molten steel. This tundish for continuous casting includes an accommodating portion for storing supplied molten steel. The accommodating portion includes: one or a plurality of molten steel outflow ports allowing the molten steel to flow out; and a gas supply portion which is disposed further upstream, in the direction of flow of the molten steel, than the one or plurality of molten steel outflow ports, and which supplies an inert gas into a space surrounded by the accommodating portion. The gas supply portion comprises: a porous portion which is formed in the shape of a box having a bottom portion and a wall portion, and which has a plurality of pores formed over the entirety thereof; a supporting portion which supports the porous portion and which is provided in the wall portion of the gas supply portion; and piping which is provided in the wall portion of the gas supply portion between the supporting portion and the bottom portion of the gas supply portion, and which ejects the inert gas.
SINTERING PROCESS CONTROL METHOD, OPERATION GUIDANCE METHOD, SINTERED ORE MANUFACTURING METHOD, SINTERING PROCESS CONTROL DEVICE, OPERATION GUIDANCE DEVICE, SINTERING OPERATION GUIDANCE SYSTEM, AND TERMINAL DEVICE
Provided is a sintering process control method which uses a physical model, which can calculate the state of a sintering process including a temperature distribution of a sintering raw material in the longitudinal direction and thickness direction in a sintering machine, to control the sintering process, wherein the sintering process control method comprises: a first prediction step (S2) for using the physical model to obtain first future predicted values of control variables when the current operation variables are maintained; and an operation amount calculation step (S5) for calculating an operation amount of a specific operation variable so as to reduce the difference between target values and overlapping predicted values of the control variables, which are based on the first predicted values and a step response when specific operation variables, which are a portion of the operation variables, are changed by a unit quantity.
Provided is a method that makes it possible to more easily and quantitatively obtain the surface wettability of a solid with respect to a discretionary liquid. The present invention is a method for evaluating the wettability of solid surfaces in which surfaces to be evaluated in two solids are made to face each other with a space therebetween, at least all of the bottom edge sections of the two solids are arranged so as to be present on the same plane and the result is used as a test material, an immersion test is performed in which the test material is immersed in an evaluation liquid so that all of the bottom edge section of the test material is parallel to the surface of the evaluation liquid, a wetting height which is the difference between the height of the surface of the evaluation liquid and the height of the liquid surface of the evaluation liquid entering into a gap between the two solids is measured at a discretionary immersion time, and the measured value is designated as a wettability evaluation value for the solid surfaces with respect to the evaluation liquid.
Provided is a mixed powder for powder metallurgy that uses a fatty acid amide, which is a clean lubricant, and that exhibits excellent compression properties and removability of a molded article, not only at normal temperatures but also after a rise in mold temperature. The mixed powder for powder metallurgy comprises an iron-based powder and a fatty acid amide as a lubricant, wherein: the fatty acid amide includes a saturated fatty acid bisamide, a saturated fatty acid monoamide, and an unsaturated fatty acid amide; the unsaturated fatty acid amide includes an unsaturated fatty acid bisamide and/or an unsaturated fatty acid monoamide; and when the added amounts of the saturated fatty acid bisamide, the saturated fatty acid monoamide, the unsaturated fatty acid bisamide, and the unsaturated fatty acid monoamide in terms of parts by mass with respect to 100 parts by mass of the iron-based powder are represented as b1, b2, b3, and b4, respectively, the following expressions (1) to (3) are satisfied. (1): 0<(b1)+(b2)+(b3)+(b4)≤2.0 (2): 0<(b1)/(b2)<0.45 (3): 0<[(b3)+(b4)]/[(b1)+(b2)+(b3)+(b4)]≤0.35
B22F 1/10 - Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
B22F 1/00 - Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
B22F 1/105 - Metallic powder containing lubricating or binding agents; Metallic powder containing organic material containing inorganic lubricating or binding agents, e.g. metal salts
Provided are: a laser welding method to prevent cracks and obtain welded joints having excellent weld metal toughness; and a laser welded joint. This laser welding method comprises: butting steel material members together; coating the surface of the steel material including a weld line with a flux having a predetermined composition; and then performing laser welding to create a welded joint, wherein the steel material has a chemical composition containing, in mass%, 0.04-0.15% of C, 0.05-1.00% of Si, 0.50-2.50% of Mn, 0.030% or less of P, 0.020% or less of S, 0.050% or less of Al, 0.050% or less of Ti, 0.010% or less of O, and 0.008% or less of N, with the remainder comprising Fe and inevitable impurities, and having a carbon equivalent Ceq of 0.30-0.45 as expressed by equation (1). (1): Ceq=[C]+[Mn]/6+[Si]/24+[Cu]/20+[Ni]/40+[Cr]/5+[Mo]/4
Provided is a square steel pipe having excellent buckling resistance. In this square steel pipe, which has a plurality of flat portions and corner portions alternating in the pipe circumference direction, the yield strength of the flat portions in the pipe circumference direction is set to be 0.83-1.20 times the yield strength of the flat portions in the pipe axial direction, and the yield strength of the corner portions in the pipe circumference direction is set to be 0.90-1.30 times the yield strength of the flat portions in the pipe axial direction.
Provided is a resin-coated metal sheet that achieves slipperiness, scrape resistance, and ink adhesiveness with respect to a resin coating layer. This resin-coated metal sheet 1 comprises a resin coating layer 3 that is formed on at least one surface of a metal sheet 2, and that contains at least 75% by mass of a polyester resin in relation to the total resin content. The resin coating layer 3 has at least a three-layer structure including a topmost layer 3a, a middle layer 3b, and a bottommost layer 3c. The melting point of the resin coating layer 3 is 230°C to 254°C, inclusive. The topmost layer 3a contains a polyolefin. The melting point of the polyolefin is 80°C to 140°C, inclusive. When measured by Raman spectroscopy, the dispersed particle size of the polyolefin on the topmost surface and the interior in the thickness direction of the resin coating layer 3 is 0.018 µm to 5.0 µm, inclusive.
B32B 15/09 - Layered products essentially comprising metal comprising metal as the main or only constituent of a layer, next to another layer of a specific substance of synthetic resin comprising polyesters
Provided is a resin-coated metal plate for a container, in which breakage of a resin coating layer in can making, and planing of the resin coating layer due to insufficient ability to slide during can making can be suppressed, and the plate has excellent adhesion to printing paint after can making. A resin-coated metal plate 1 for a container comprises a polyester resin coating layer 3 on at least one surface of a metal plate 2, the polyester resin coating layer 3 containing 0.010-1.0 mass% of an organic lubricant in which the half-value width of a peak due to C=O stretching vibration in the vicinity of 1730 cm-1is 24 cm-1to 28 cm -1, determined by laser Raman spectroscopy analysis from measurement with linearly polarized laser light having a wavelength of 532 nm incident on the surface of the polyester resin coating layer 3 with the plane of polarization of the laser light parallel to the rolling direction of the metal plate, and the contact angle of diiodomethane on the surface of the polyester resin coating layer after heat treatment for two minutes from room temperature to 240°C being 23-40°.
B32B 15/09 - Layered products essentially comprising metal comprising metal as the main or only constituent of a layer, next to another layer of a specific substance of synthetic resin comprising polyesters
B65D 25/36 - Coverings or external coatings formed by applying sheet material
95.
STEEL SHEET FOR HOT PRESSING, HOT-PRESSED MEMBER AND METHOD FOR PRODUCING HOT-PRESSED MEMBER
Provided is a steel sheet for hot pressing that has excellent rapid heating compatibility, that can prevent liquid metal embrittlement cracking, and that has excellent post-hot-pressing coating adhesion. The steel sheet for hot pressing comprises: a base steel sheet; and a coating layer which is provided on both surfaces of the base steel sheet and which has a thickness of 0.5 to 6.0 µm. The coating layer is formed of Ni or an Ni-based alloy, and the Zn content in the coating layer is 0-30 mass%.
C23C 14/16 - Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon
C23C 28/00 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and
C25D 5/26 - Electroplating of metal surfaces to which a coating cannot readily be applied of iron or steel surfaces
C25D 5/48 - After-treatment of electroplated surfaces
96.
HIGH-STRENGTH HOT-DIP-GALVANIZED STEEL SHEET AND PRODUCTION METHOD FOR SAME
According to the present invention, a method for producing a high-strength hot-dip-galvanized steel sheet that has at least 20 g/m2but no more than 120 g/m222 and 0.5–10.0 vol ppm of HCl, the remainder being nitrogen and unavoidable impurities. (1): Dew point X≥(-50+[Si mass%]×(T-600)/30+[Mn mass%]×(T-600)/25)
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
A method for producing a grain-oriented electromagnetic steel sheet, the method comprising hot-rolling a steel material having a given composition, cold-rolling the hot-rolled sheet to obtain a cold-rolled sheet having a final sheet thickness, and subjecting the cold-rolled sheet to decarburization annealing serving also as primary recrystallization annealing and then to finish annealing, wherein the cold-rolling includes final cold rolling conducted by at least one pass at a steel sheet temperature in the range of 150-350°C. The decarburization annealing is conducted such that in the course of temperature rising, the cold-rolled sheet is rapidly heated from 400°C to a temperature T (°C) between 700°C and 900°C at an average heating rate of 250 °C/s or higher and that a time period of 0.10 s or longer but shorter than 1.00 s is set during which the heating rate for any temperatures between 500°C and 700°C is not higher than 2/3 the average heating rate. Thus, a grain-oriented electromagnetic steel sheet having excellent magnetic properties is produced. The rapid heating in the decarburization annealing is conducted using a transverse-type induction heater.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
A method for producing a grain-oriented electromagnetic steel sheet, the method comprising: hot-rolling a steel material to obtain a hot-rolled sheet; subjecting the hot-rolled sheet to cold rolling once or subjecting the hot-rolled sheet to cold rolling two or more times and to process annealing interposed therebetween, thereby obtaining a cold-rolled sheet having a final sheet thickness; and subjecting the cold-rolled sheet to decarburization annealing serving also as primary recrystallization annealing and then to finish annealing. The decarburization annealing is conducted such that in the course of temperature rising, the cold-rolled sheet is rapidly heated from 400°C to a temperature T (°C) between 700°C and 900°C at an average heating rate of 250 °C/s or higher and that a time period of 0.10 s or longer but shorter than 1.00 s is set during which the heating rate for any temperatures between 500°C and 700°C is not higher than 2/3 the average heating rate. Thus, a grain-oriented electromagnetic steel sheet having excellent magnetic properties is produced. The rapid heating in the decarburization annealing is conducted using a transverse-type induction heater.
C21D 8/12 - Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
A molten iron refining method having, an auxiliary material, and an oxidizing gas supplied through a top-blowing lance, to a cold iron source and molten pig iron that are contained/fed in a converter-type vessel, and molten iron is subjected to a refining process. A pre-charged cold iron source is charged into the converter-type vessel at an amount not larger than 0.15 times. A furnace-top-added cold iron source that's part or all of the cold iron source and added from a furnace top is fed during the refining process. A burner at a leading end of the top-blowing lance that spray holes through which a fuel and a combustion-supporting gas are ejected. During the refining process, a powdery auxiliary material processed into powder that's part of the auxiliary material is blown in, to pass through a flame formed by the burner.