Abstract: A carburized shaft part having a predetermined composition, a C content at a surface layer part of a mass % of 0.60 to 1.00%, at least one hole at an outer circumferential surface, a total volume ratio of martensite and retained austenite of 97% or more at a structure at a position of a 1 mm depth from the outer circumferential surface in an axial direction of the hole and a position of a 20 ?m depth from the surface of the hole, a maximum retained austenite volume ratio (R1) of 10.0 to 30.0% at a position of a 1 mm depth from the outer circumferential surface in the axial direction of the hole and a range up to a 200 ?m depth from the surface of the hole, and a retained austenite reduction ratio of 20% or more found from R1 and the retained austenite volume ratio (R2) at a position of a 1 mm depth from the outer circumferential surface in the axial direction of the hole and a position of a 20 ?m depth from the surface of the hole by the formula (A): ??=(R1?R)/R1×100.

Abstract: According to an aspect of the present invention, there is provided a steel containing, by unit mass %, C: 0.08% to 0.12%, Si: 0.05% to 0.50%, Mn: 1.50% to 3.00%, P: 0.040% or less, S: 0.020% or less, V: 0.010% or less, Ti: 0.010% or less, Nb: 0.005% or less, Cr: 1.00% to 2.50%, Cu: 0.01% to 0.50%, Ni: 0.75% to 1.60%, Mo: 0.10% to 0.50%, Al: 0.025% to 0.050%, N: 0.0100% to 0.0200%, Ca: 0% to 0.0100%, Zr: 0% to 0.0100%, Mg: 0% to 0.0100%, and a remainder including Fe and impurities, in which a ratio of an Al content to a N content is 2.6 or less, a ratio of a Mn content to a Ni content is 1.5 or more and 3.0 or less.

Abstract: A hot press-formed part according to an aspect of the present invention contains a predetermined chemical composition; in which a microstructure in a thickness ¼ portion includes, by unit vol %, tempered martensite: 20% to 90%, bainite: 5% to 75%, and residual austenite: 5% to 25%, and ferrite is limited to 10% or less; and a pole density of an orientation {211}<011> in the thickness ¼ portion is 3.0 or higher.

Abstract: The object of the present invention is such that a surface exchange of metal fine particles by Cu ions, or the like is inhibited in order to prevent formation of Artificial CuS or the like, in extraction and analysis of the metal fine particles (inclusions and precipitates) in a metal material by electrolytic corrosion in a solvent-based electrolytic solution, without significantly changing conventional extraction and analysis methods, and such that the metal deposited on the cathode is actively attached to the cathode so that the deposited metal does not become a contamination source.

Abstract: The object of the present invention is such that a surface exchange of metal fine particles by Cu ions, or the like is inhibited in order to prevent formation of Artificial CuS or the like, in extraction and analysis of the metal fine particles (inclusions and precipitates) in a metal material by electrolytic corrosion in a solvent-based electrolytic solution, without significantly changing conventional extraction and analysis methods.

Abstract: A chemical treatment steel sheet includes a steel sheet, an Fe—Sn alloy layer which is formed on at least one surface of the steel sheet, a Sn layer which is formed on the Fe—Sn alloy layer and contains Sn in which a total amount of Sn contained in the Fe—Sn alloy layer and the Sn layer is 0.10 to 30.0 g/m2, and a chemical treatment layer which is formed on the Sn layer and contains a Zr compound in which an amount of Zr contained therein is 1.0 to 150 mg/m2, a phosphate compound in an amount of P contained therein is 1.0 to 100 mg/m2 and an Al compound in an amount of Al contained therein is 0.10 to 30.0 mg/m2.

Abstract: Steel wire rod etc. enabling elimination the heat treatment processes of spheroidizing annealing and of quenching and tempering are provided. A predetermined chemical composition is provided, 90% or more of the microstructure by area ratio is bainite, the mean bainite block size of the surface layer measured at the cross-section is 15 ?m or less, the ratio of the mean bainite block size of the surface layer measured at the cross-section and the mean bainite block size measured at the center part is less than 1.0, and the mean particle size of cementite dispersed in bainite is 0.1 ?m or less.

Abstract: A selective emitter exhibiting heat resistance up to 1000° C., comprising a metal body, a first dielectric layer provided on one surface of the metal body, a composite layer provided on another surface of the first dielectric layer at an opposite side to the metal body side, and a second dielectric layer provided on another surface of the composite layer at an opposite side to the first dielectric layer, the composite layer being a layer provided with a metal or semiconductor dispersed in an oxide of the metal or the semiconductor.

Abstract: A chemical treatment steel sheet contains: a steel sheet; a plated layer containing Ni and formed on at least one surface of the steel sheet; a chemical treatment layer containing a Zr compound in which an amount of Zr contained therein is 1.0 to 150 mg/m2, a phosphate compound in which an amount of P contained therein is 1.0 to 100 mg/m2, and an Al compound in which an amount of Al contained therein is 0.10 to 30.0 mg/m2. The plated layer is a Ni-plated layer containing Ni in which an amount of Ni contained therein is 5.0 to 3000 mg/m2 or a composite plated layer containing Ni in which an amount of Ni contained therein is 2.0 to 200 mg/m2 and Sn in which an amount of Sn contained therein is 0.10 to 10.0 g/m2 and having an island-shaped Sn-plated layer formed on a Fe—Ni—Sn alloy layer.

Abstract: An austenitic alloy material is provided that includes a base metal having a surface, and a film containing chromium oxide having a thickness of 0.1 to 50 ?m on at least one portion of the surface. A chemical composition at a depth position in the film at which the Cr concentration is highest contains, by atom %, 50% or more of Cr as a proportion occupied among components excluding O, C and N. The chemical composition of the base metal consists of, by mass %, C: 0.001 to 0.6%, Si: 0.01 to 5.0%, Mn: 0.1 to 10.0%, P: 0.08% or less, S: 0.05% or less, Cr: 15.0 to 55.0%, Ni: 30.0 to 80.0%, N: 0.001 to 0.25%, O: 0.02% or less, Mo: 0 to 20.0%, Cu: 0 to 5.0%, Co: 0 to 5.0%, W: 0 to 10.0%, Ta: 0 to 6.0%, Nb: 0 to 5.0%, Ti: 0 to 1.0%, B: 0 to 0.1%, Zr: 0 to 0.1%, Hf: 0 to 0.1%, Al: 0 to 1.0%, Mg: 0 to 0.1%, and Ca: 0 to 0.1%, the balance being Fe and impurities.

Abstract: There is provided a non-oriented electrical steel sheet for a stator core of a claw pole motor, the non-oriented electrical steel sheet is a strip-shaped steel sheet in which magnetic flux density in a direction forming 45° with respect to a rolling direction is higher than magnetic flux density in the rolling direction and magnetic flux density in a transverse direction that is a direction forming 90° with respect to the rolling direction.

Abstract: Cooling equipment comprising: a plurality of injection units in a continuous annealing furnace including heating zone, soaking zone, and cooling zone through which strip-shaped steel sheet is sequentially fed, the injection units arranged in cooling zone in row along feed direction of steel sheet and injecting, from injection nozzles, cooling gas containing hydrogen, onto steel sheet; and hydrogen concentration adjustment unit adjusts hydrogen concentration of cooling gas such that hydrogen concentration distribution is formed in which, in a space of the cooling zone where plurality of injection units are disposed, hydrogen concentration at upstream region is higher than hydrogen concentration at downstream region; plurality of injection nozzles arranged along feed direction of steel sheet, and each of injection nozzles extending toward steel sheet; and injection nozzles positioned at both sides in array direction inclined to slope toward a center of the array direction on progression toward tips of injection

Abstract: According to an aspect of the present invention, there is provided a flux-cored wire including a steel sheath and a flux that fills the steel sheath. The flux contains fluorides of which a total value a of F-equivalent values is 0.21% or more, oxides of which the total value ? of amounts ranges from 0.30% to less than 3.50%, and carbonates of which a total value of amounts ranges from 0% to 3.50%. An amount of CaO ranges from 0% to less than 0.20%. An amount of iron powder ranges from 0% to less than 10.0%. A X-value is 5.0% or less. The amount of CaF2 is less than 0.50%. The amount of Ti oxides ranges from 0.10% to less than 2.50%. A ratio of ? to ? ranges from 0.10 to 4.00. A total value of amounts of MgCO3, Na2CO3, and LiCO3 ranges from 0% to 3.00%. Other chemical composition is within a predetermined range. Ceq ranges from 0.45% to 1.20%.

Abstract: A ceramic laminate improving the mechanical characteristics of a composite ceramic layer which has excellent thermal fatigue resistance, thermal conductivity, and insulation ability and having excellent durability and heat dissipation and insulation ability and a ceramic insulating substrate and a method of production of a ceramic laminate are provided. In a cross-section perpendicular to the bonding interfaces, the average size of the second phase particles 3 is 0.02 ?m to 0.3 ?m and the average value of the ratio of the long axis and short axis of an equivalent ellipse when viewing a second phase particle 3 as an ellipse is 2 to 10. Further, 60% or more of the number of the second phase particles 3 has an orientation angle of 30° or less while the average orientation angle is 5° to 35°.

Abstract: A steel sheet includes a predetermined chemical composition and a metal structure represented by, in area fraction, ferrite: 50% to 95%, granular bainite: 5% to 48%, martensite: 2% to 30%, and upper bainite, lower bainite, tempered martensite, retained austenite, and pearlite: 5% or less in total.

Abstract: A nitrided part excellent in contact fatigue strength plus rotating bending fatigue strength, the nitrided part having a steel material having a predetermined chemical composition as a material, wherein the nitrided part comprises a compound layer formed on the surface of the steel material, the compound layer containing iron, nitrogen, and carbon, a thickness of the compound layer being 3 ?m to less than 20 ?m; a phase structure in the compound layer in a range from the surface down to a depth of 5 ?m contains ?? phases in an area ratio of 50% or more; a pore area ratio in a range from the surface down to a depth of 3 ?m is less than 10%; and a compressive residual stress of the compound layer surface is 500 MPa or more.

Abstract: A collapse strength prediction method of a steel pipe includes deriving a prediction equation indicating a relationship among D/t obtained by dividing an outer diameter D (mm) by a thickness t (mm), material characteristics, a collapse strength dominant factor, and a collapse dominant proof stress (?CDOS) of the steel pipe using a plurality of reference steel pipes collapse whose strengths have been obtained in advance, obtaining D/t, material characteristics, a collapse strength dominant factor, and a predicted collapse strength of a steel pipe that is an evaluation subject, obtaining a compressive stress-strain curve in a circumferential direction of the steel pipe that is the evaluation subject, obtaining a stress that causes a permanent strain to be generated in the steel pipe that is the evaluation subject as the collapse dominant proof stress on the basis of the compressive stress-strain curve, and computing the predicted collapse strength of the steel pipe that is the evaluation subject from the D/t, t

Abstract: A steel sheet includes a predetermined chemical composition and a metal structure represented by, in area fraction, ferrite: 30% to 50%, granular bainite: 5% to 20%, martensite: 30% to 55%, bainite: less than 35%, and retained austenite and pearlite: 10% or less in total. Preferably, of the steel sheet, a tensile strength is 1180 MPa or more, elongation is 10% or more, and a hole expansion value is 20% or more. Further preferably, a VDA bending angle in the case where a thickness is set to t (mm) is “7.69t2?38.4t+109” or more.

Abstract: A nitrided part excellent in bending straightening ability plus rotating bending fatigue strength and a method of production of the same, the nitrided part having a steel material having a predetermined chemical composition as a material, wherein the nitrided part comprises a compound layer formed on the surface of the steel material, the compound layer containing iron, nitrogen, and carbon, and a thickness of the compound layer being 3 ?m to less than 15 ?m; a phase structure in the compound layer in a range from the surface down to a depth of 5 ?m contains ?? phases in an area ratio of 50% or more, a pore area ratio in a range from the surface down to a depth of 3 ?m is less than 10%, and a compressive residual stress of the compound layer surface is 500 MPa or more.

Abstract: This fracture determination device 1 is provided with: an element extraction unit 22 which extracts elements included in the heat affected zone formed around a spot weld in a steel material; a reference forming limit value generation unit 23 which generates a reference forming limit value depending on sheet thickness and material property of the heat affected zone on the basis of reference forming limit value information; a heat affected zone forming limit value generation unit 24 which uses the tensile strength of the steel material and element size to change the reference forming limit value, predict the forming limit value for the element size and generated a forming limit value in the heat affected zone; an analysis running unit 25 which runs a deformation SIM using input information and which outputs deformation information including maximum principal strain and minimum principal strain of each of the elements; a principal strain determination unit 26 which determines the maximum principal strain and the