Abstract: A cold rolling mill rolling condition setting method using a prediction model being generated with an explanatory variable being first multi-dimensional data obtained by transforming past rolling performance data including pre-cold rolling data of a roll material on an entry side of the cold rolling mill into multi-dimensional data, and an objective variable being post-cold rolling data of the roll material on a delivery side of the cold rolling mill, the method includes: estimating a post-rolling shape of a roll target material by inputting, to the prediction model, second multi-dimensional data generated from information including the pre-cold rolling data of the roll target material on the entry side of the cold rolling mill and a target rolling condition of the cold rolling mill; and changing the target rolling condition of the cold rolling mill such that the estimated post-rolling shape of the roll target material satisfies a predetermined condition.

Abstract: To provide a battery-driven motor and a motor-driven system that achieve high output density without compromising overall system efficiency, a battery-driven motor is supplied electric power from a battery via an inverter to drive a load, wherein current supplied from the battery is 3.0 C or more when driven at maximum output, the battery-driven motor including a stator core (12) provided with an electrical steel sheet as an iron core material that has a magnetic flux density of 1.65 T or more at a magnetic field strength of 5,000 A/m and an iron loss of 40.0 W/kg or less under sinusoidal excitation of 1 kHz-1.0 T.

Abstract: Proposed is a method for producing a grain-oriented electrical steel sheet that comprises heating a steel material containing a certain composition and inhibitor-forming ingredients to a temperature in a range of 1300 to 1400° C.; performing hot rolling, hot-band annealing, and cold rolling on the material to obtain a cold-rolled sheet; performing decarburization annealing also serving as primary recrystallization annealing on the cold-rolled sheet; subsequently applying an annealing separator to a surface of the steel sheet; and performing finishing annealing followed by applying an insulation coating. In the method, rapid heating is conducted from 500 and 700° C. in a heating process of the decarburization annealing at a rate of 100 to 1000° C./s while gradual heating is conducted from 860 to 970° C. in a heating process of the finishing annealing at a heating rate of 0.5 to 4.0° C./hr for at least 10 hours.

Abstract: To provide a galvanized steel sheet having high strength; specifically, with a tensile strength of 1160 MPa or more and excellent resistance spot weldability. A chemical composition of a base steel sheet contains one or more of Ti, Nb, V, and Zr: 0.02% or more and 0.20% or less in total, and an amount of diffusible hydrogen in a zinc or zinc alloy coating layer is 0.40 mass ppm or less.

Abstract: A steel pipe for high-pressure hydrogen, the steel pipe having a chemical composition containing, by mass %, C: 0.05% to 0.60%, Si: 0.001% to 2.0%, Mn: 0.01% to 5.0%, P: 0.030% or less, S: 0.010% or less, N: 0.010% or less, Al: 0.0001% to 1.00%, 0: 0.010% or less, H: 0.00010% or less, and a balance of Fe and incidental impurities and a metallic microstructure including, in terms of area fraction, 3% or less (including 0%) of retained austenite, in which the number of inclusions having an aspect ratio of 2.0 or more and a length of 10 ?m or more is 15/100 mm2 or less.

Abstract: In performing friction element welding of a sheet set constituted by two or more metal sheets, an element is press penetrated into the sheet set. The element may include a round columnar mandrel; a disc-shaped collar provided at an upper end face of the mandrel; and a conical pin extending from a lower end face of the mandrel. The element has a plurality of fluidized-metal discharge grooves arranged spirally in a flat area of the lower end face of the mandrel, the flat area excluding the pin. Alternatively, the element may include a round columnar mandrel having a lower end face that forms a conical face with an apical angle ?m, the conical face having one or more pairs of chippings discharge grooves or having a plurality of cutting edges, the chippings discharge grooves each extending in a curved manner from an apex of the conical face.

Abstract: A clad steel plate having tensile strength (TS) of 780 MPa or more, excellent bendability, collision resistance, and LME resistance. The clad steel plate having a base metal and a cladding metal on front and back surfaces of the base metal, and the chemical composition and microstructure of the base metal and the cladding metal being appropriately controlled so that the average Vickers hardness (HVL) of the cladding metal is 260 or less, the average Vickers hardness (HVL) of the cladding metal divided by the average Vickers hardness (HVB) of the base metal is 0.80 or less, the boundary roughness between the base metal and the cladding metal is 50 ?m or less at the maximum height Ry, and the number of voids at the boundary between the base metal and the cladding metal is controlled to 20 or fewer per 10 mm length of the boundary.

Abstract: Provided are a gas-shielded arc welding method, a welded joint, and a method for producing the welded joint. In gas-shielded arc welding including one-side butt welding of steel plates in the present invention, a ceramic-made backing material is attached to a bottom surface of a groove, and root pass is performed in one pass using a welding current I of 200 to 450 A and a welding voltage V of 25 to 50 V while a welding heat input Q is controlled within the range defined by formula 1 below. 0.4× G?1 ?Q ?0.6× G+1 (formula 1) Here, G in formula 1 is a root gap (mm).

Abstract: To provide a galvanized steel sheet having high strength, specifically, a tensile strength of 1,150 MPa or more, and excellent resistance spot weldability, a base steel sheet has a defined chemical composition, an amount of diffusible hydrogen in the base steel sheet is 0.20 mass ppm or less, and surface roughness Ra of the galvanized steel sheet is 0.6 ?m or less.

Abstract: A refining vessel for high-temperature melt includes a refractory for gas blowing nozzle that includes a central refractory embedded with metal tubules, and an outer refractory circumferentially surrounding the central refractory. The refractory for gas blowing nozzle has a horizontal projection on which a minimum radius of an imaginary circle encompassing all the metal tubules embedded in the central refractory is R (mm), wherein the central refractory has an outline that falls between one circle that is concentric with the imaginary circle and has a radius of R+10 mm, and another circle that is concentric with the imaginary circle and has a radius of R+150 mm. The central refractory is formed of a MgO—C refractory having a carbon content of 30 to 80 mass %, and the outer refractory is formed of a MgO—C refractory having a carbon content of 10 to 25 mass %.

Abstract: A steel sheet including a chemical composition satisfying an equivalent carbon content of 0.60% or more and less than 0.85%, and a steel microstructure with an area fraction of ferrite: less than 40%, tempered martensite and bainite: 40% or more in total, retained austenite: 3% to 15%, and ferrite, tempered martensite, bainite, and retained austenite: 93% or more in total. A 90-degree bending at a curvature radius/thickness ratio of 4.2 in a rolling (L) direction with respect to an axis extending in a width (C) direction causes a change of 0.40 or more in (a grain size in a thickness direction)/(a grain size in a direction perpendicular to the thickness) of the tempered martensite in an L cross section in a 0- to 50-?m region from a surface of the steel sheet on a compression side. The steel sheet has a tensile strength of 980 MPa or more.

Abstract: A crashworthiness energy absorption part includes: a tubular member having tensile strength of 590 to 1180 MPa grade; a closed cross section space forming wall part having tensile strength lower than the tubular member and having both edge portions joined to inner surfaces of a pair of side wall portions of the tubular member, and forming a closed cross section space between the closed cross section space forming wall part and a part of a peripheral wall portion of the tubular member; and a resin configured to fill the closed cross section space, includes a rubber-modified epoxy resin and a curing agent, and has tensile breaking elongation of 80% or more, adhesive strength to the tubular member and closed cross section space forming wall part of 12 MPa or higher, and a compression nominal stress of 6 MPa or higher at a compression nominal strain of 10%.

Abstract: An automotive frame part is provided to a side portion of an automotive body and absorbs crashworthiness energy by bending upon receiving a crashworthiness load from a side of the automotive body. The automotive frame part includes: a member having a hat-shaped cross section or a U-shaped cross section and including a top portion, and a pair of side wall portions that are continuous from the top portion via punch shoulder R portions; and resin that is coated on or patched to an internal surface of the member having the hat-shaped cross section member or the U-shaped cross section. The resin extends at least to a predetermined range toward the top portion and the side wall portions on both sides of the punch shoulder R portions, and is adhered, after heating, to the internal surface at an adhesive strength of 10 MPa or higher at a room temperature.

Abstract: The high-strength steel sheet has a chemical composition with MSC value in the range of 2.7% to 3.8% by mass defined by a specific formula, wherein the high-strength steel sheet has a microstructure including specific microstructures in a surface layer region extending from the surface of the steel sheet to a depth of 100 ?m and in an inner region other than the surface layer region. The high-strength steel sheet has the maximum height of the surface roughness of 30 ?m or less, a tensile strength of 980 MPa or more, a uniform elongation of 6% or more, and a ratio of 107-cycle plane bending fatigue strength to tensile strength (fatigue limit ratio) of 0.45 or more.

Abstract: A formed article having a polygonal tube shape is produced by performing polygonal tube deep drawing on a blank made of a steel sheet, the formed article including a bottom surface part having a polygonal shape, a side wall including a straight side part continuous with a side of the bottom surface part and a vertical ridge connecting ends, in the right-left direction, of adjacent straight side parts, and a flange continuous with the side wall. A side of a flange region to become the flange in the blank includes a notch, and the notch is formed on the side of a part of the flange region, the part being continuous with a region at a position closer to the vertical ridge than a position of a central part in the right-left direction in the straight side part.

Abstract: There is provided a steel sheet for cans including, on a surface of a steel sheet, a chromium metal layer and a hydrated chromium oxide layer stacked in this order from the steel sheet side. The chromium metal layer has a coating weight of 50 to 200 mg/m2, and the hydrated chromium oxide layer has a coating weight of 3 to 30 mg/m2 in terms of chromium amount. The chromium metal layer includes a base portion of flat plate shape and granular protrusions provided on the base portion. At least 20% of the granular protrusions has a circularity C of 0.85 or less. The circularity C is expressed by C=4?A/U2, when the outer perimeter of a projection image of a granular protrusion is represented by U, and the area thereof is represented by A.

Abstract: A resin-coated metal sheet for containers includes a metal sheet and oriented films coating both surfaces of the metal sheet and made of a polyester resin, wherein the polyester resin includes 92 mol % or more of an ethylene terephthalate unit, the full-width at half maximum of a C?O peak at 1725 cm?1±5 cm?1 is 20 cm?1 or more and 25 cm?1 or less in Raman spectroscopy in an orientation direction of the surfaces of the films after coating the metal sheet, and the ratio (I1725/I1615) of the C?O peak intensity at 1725 cm?1±5 cm?1 to the C?C peak intensity at 1615 cm?1±5 cm?1 is 0.50 or more and 0.70 or less in the Raman spectroscopy.

Abstract: An automotive-structural-part joint structure is formed by bending one metal sheet, includes a groove portion including a top portion and a pair of side wall portions, is provided at an end part of one automotive structural part in a longitudinal direction, and is configured to join the one automotive structural part to another automotive structural part in an intersecting direction. The automotive-structural-part joint structure includes: a pair of vertical rib portions configured to stand upward from both side ends of the top portion; and an outward-directed flange portion configured to extend outward from three side edges of the groove portion on an end part side where the other automotive structural part is joined, the flange portion being continuously formed along the three side edges.

Abstract: A method includes two or more reference strain gradient information being a relationship between the strain at the hole edge and a strain gradient along a radial direction. Hole expansion forming is performed on the evaluation metal sheet under the same forming conditions as respective forming conditions corresponding to at least two pieces of the reference strain gradient information to obtain at least two limit hole expansion ratios at a hole expansion limit of the evaluation metal sheet. A formable region of the evaluation metal sheet is obtained from the at least two pieces of the reference strain gradient information and the obtained at least two limit hole expansion ratios at the hole expansion limit. Stretch flange cracking at the sheared end face of the evaluation metal sheet is evaluated by the obtained formable region.

Abstract: The method includes slab-heating a steel slab to a temperature of higher than a ?-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 ?t 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.