Abstract: A plated steel sheet for automobile structural members has a steel sheet, a plating layer formed on at least a part of a surface of the steel sheet, and an oxide layer formed on at least a part of a surface of the plating layer, the plating layer has a predetermined chemical composition, and when measurement by XPS is performed at a position 5.0 nm below a surface of the oxide layer in a thickness direction, IMg/IMgOx, which is the ratio of a maximum detected intensity of Mg to a maximum detected intensity of an oxide or hydroxide of Mg, is 0.00 or greater and 1.20 or less.

Abstract: A plated steel material having a plating layer having an average chemical composition containing, in mass %, Zn: more than 50.00%, Al: more than 15.0% and less than 30.0%, Mg: more than 5.0% and less than 15.0%, and Si: 0.25% or more and less than 3.50%, and impurities, and wherein a total amount (?A) of at least one selected from the group consisting of Sn, Bi and In is less than 1.00%, a total amount (?B) of at least one selected from the group consisting of Ca, Y, La, Ce and Sr is 0.02% or more and less than 0.60%, 2.0?SMg/Si<20.0 (Formula 1), 3.0?Si/?B<24.0 (Formula 2), and 26.0?(Si/?B)×(Mg/Si)<375.0 (Formula 3) are satisfied, and in an X-ray diffraction pattern of the surface of the plating layer, a diffraction intensity ratio R1 defined by R1={I(16.18°)+I(32.69°)}/I(27.0°) (Formula 4) satisfies 2.5<R1 (Formula 5) is used.

Abstract: A steel sheet comprising, by mass %, C: 0.05 to 0.40%, Si: 0.2 to 3.0%, and Mn: 0.1 to 5.0%, wherein a surface layer of the steel sheet contains granular oxides, an average grain size of the granular oxides is 300 nm or less, a number density of granular oxides is 4.0/?m2 or more, the steel sheet comprises an Si—Mn depleted layer having a thickness of 3.0 ?m or more from the surface of the steel sheet, and Si and Mn contents of the Si—Mn depleted layer not containing oxides at the ½ position of the thickness are respectively less than 10% of the Si and Mn contents at the sheet thickness center part of the steel sheet, and a plated steel sheet using the same are provided.

Abstract: A steel welded member comprising a plurality of Zn-based plated steel materials, each having a Zn-based plating layer on a surface of a steel material, joined together through at least one spot weld, wherein the steel material contains, by mass %, C: 0.05 to 0.40%, Si: 0.2 to 3.0%, and Mn: 0.1 to 5.0%, the steel welded member includes, by area ratio, 20 to 80% of a ? phase (Fe3 Zn1 0) and at least one oxide with a long axis of 0.5 ?m or more in a region up to 0.5 mm from an end part of a pressure weld of the spot weld.

Abstract: A steel sheet comprising, by mass %, C: 0.05 to 0.40%, Si: 0.2 to 3.0%, and Mn: 0.1 to 5.0%, wherein a surface layer of the steel sheet contains grain boundary oxides, a Ratio A of a length of the grain boundary oxides projected on a surface of the steel sheet to a length of the surface of the steel sheet is 50% or more and 100% or less, a number density of granular oxides is less than 4.0/?m2, the steel sheet comprises an Si—Mn depleted layer having a thickness of 3.0 ?m or more from the surface of the steel sheet, and Si and Mn contents of the Si—Mn depleted layer at the ½ position of the thickness and not containing oxides are respectively less than 10% of the Si and Mn contents at a sheet thickness center part of the steel sheet, and a plated steel sheet using the same are provided.

Abstract: A hot stamped body comprising a steel base material and an Al—Zn—Mg-based plating layer formed on a surface of the steel base material, wherein the plating layer has a predetermined chemical composition, the plating layer comprises an interfacial layer positioned at an interface with the steel base material and containing Fe and Al and a main layer positioned on the interfacial layer, the main layer comprises, by area ratio, 10.0 to 90.0% of an Mg—Zn containing phase, 5.0 to less than 30.0% of an Fe—Al containing phase, and 2.0 to 25.0% of an Al—Si containing oxide phase, the Mg—Zn containing phase comprises at least one selected from the group consisting of an MgZn phase, Mg2Zn3 phase, and MgZn2 phase, and the Fe—Al containing phase comprises at least one of an FeAl phase and Fe—Al—Zn phase.

Abstract: A plated steel sheet includes: a steel sheet; and a plating layer that is formed on at least a part of a surface of the steel sheet, in which a chemical composition of the plating layer includes, b mass %, Al: 6.00% to 35.00 %, Mg: 3.00% to 15.00%, La+Ce: 0.0001% to 0.5000% in total, and Zn, and in a surface of the plating layer, the area ratio of a lamellar structure in which an (Al—Zn) phase and a MgZn2 phase are arranged in layers is 10% to 95%, the lamellar spacing of the lamellar structure is 2.5 ?m or less, and the area ratio of an (Al—Zn) dendrite is 10% or less.

Abstract: High strength plated steel sheet having high hydrogen embrittlement resistance, that is, alloyed hot dip galvannealed steel sheet including steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50% and a alloyed hot dip galvannealed layer deposited on at least one surface of the steel sheet to 10 to 100 g/m2 and containing Fe: 5.0 to 15.0% and Al: 0.01 to 1.0%, having an internal oxidation layer including grain boundary oxides in a surface layer of the steel sheet, when examining a cross-section of a surface layer of the steel sheet, a Ratio A of the length of the grain boundary oxides projected an interface of the steel sheet and the alloyed hot dip galvannealed layer to the length of interface is 50% or more and 100% or less, and a surface depleted layer with a steel composition not including the grain boundary oxides which satisfies, by mass %, Si?0.6% and Al?0.05% is included at a depth of ½ of the average depth of the internal oxidation layer.

Abstract: A hot stamped steel includes a base material, a plated layer that is formed on a surface of the base material, and an oxide film that is formed on a surface of the plated layer; chemical composition of the plated layer contains 20.00 to 45.00 mass % of Al, 10.00 to 45.00 mass % of Fe, 4.50 to 15.00 mass % of Mg, 0.10 to 3.00 mass % of Si, 0.05 to 3.00 mass % of Ca, 0 to 0.50 mass % of Sb, 0 to 0.50 mass % of Pb, 0 to 1.00 mass % of Cu, 0 to 1.00 mass % of Sn, 0 to 1.00 mass % of Ti, 0 to 0.50 mass % of Sr, 0 to 1.00 mass % of Cr, 0 to 1.00 mass % of Ni, and 0 to 1.00 mass % of Mn with a remainder of Zn and impurities; and chemical composition of the oxide film contains 20.0 to 55.0 at % of Mg, 0.5 to 15.0 at % of Ca, 0 to 15.0 at % of Zn, and 0 at % or more and less than 10.0 at % of Al with a remainder of O and a total of 5.0 at % or less of impurities, and the adhesion amount of the oxide film per one surface is in a range of 0.01 to 10 g/m2.

Abstract: High strength steel sheet and plated steel sheet having high plateability, LME resistance, and hydrogen embrittlement resistance, that is, steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50%, having an internal oxidation layer including fine granular oxides in a surface layer of the steel sheet, a number density of fine granular oxides in the internal oxidation layer being 4.0/?m2 or more, and including a surface depleted layer with a steel composition not including oxides which satisfies, by mass %, Si?0.6% and Al?0.05% at a depth of ½ of the average depth of the internal oxidation layer calculated from the cross-sectional SEM image of the steel sheet, and a plated steel sheet using the same.

Abstract: High strength steel sheet and plated steel sheet having high plateability, LME resistance, and hydrogen embrittlement resistance, that is, steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50%, having an internal oxidation layer including fine granular oxides and coarse granular oxides in a surface layer of the steel sheet, a number density of fine granular oxides in the internal oxidation layer being 4.0/?m2 or more, a number density of coarse granular oxides in the internal oxidation layer being 4.0/25 ?m2 or more and 30.0/25 ?m2 or less, and including a surface depleted layer with a steel composition not including oxides which satisfies, by mass %, Si?0.6% and Al?0.05% at a depth of ½ of the average depth of the internal oxidation layer calculated from the cross-sectional SEM image of the steel sheet, and a plated steel sheet using the same.

Abstract: This hot-dip Zn—Al—Mg-based plated steel includes: a steel; and a plating layer formed on a surface of the steel, in which the plating layer contains, as an average composition, Mg: 1 to 10 mass %, Al: 4 to 22 mass %, and a remainder consisting of Zn and impurities, the plating layer includes an (Al—Zn mixed structure) in an area ratio of 10% to 70% in a cross section of the plating layer in a matrix of an (Al/Zn/MgZn2 ternary eutectic structure), the (Al—Zn mixed structure) includes a first region that has a Zn concentration in a range of 75 mass % or more and less than 85 mass % and a second region that is present inside the first region and has a Zn concentration in a range of 67 mass % or more and less than 75 mass %, and an area ratio of the second region in the (Al—Zn mixed structure) in the cross section of the plating layer is more than 0% and 40% or less.

Abstract: The hot-dip plated steel material includes a steel material and a hot-dip plated layer disposed on a surface of the steel material, the hot-dip plated layer has a certain chemical composition, and the hot-dip plated layer has a diffraction intensity obtained from a result of X-ray diffraction measurement, the diffraction intensity satisfying a certain relationship.

Abstract: The present disclosure inhibits liquid metal embrittlement (LME) cracking and improves corrosion resistance in a welded joint obtained by spot welding a first steel sheet and a second steel sheet. In the welded joint of the present disclosure, a first plating layer is provided on a surface of the first steel sheet facing the second steel sheet, no plating layer is present on or a second plating layer is provided on a surface of the second steel sheet facing the first steel sheet, and a boundary plating layer is provided between the first steel sheet and the second steel sheet in a range of 0.5 mm from an end part of the corona bond toward an outside of the spot welded part. A higher tensile strength of a tensile strength of the first steel sheet and a tensile strength of the second steel sheet is 780 MPa or more, an area ratio of a MgZn2 phase at the cross-section of the boundary plating layer is 10% or more, and the first plating layer and the second plating layer satisfy a predetermined Relation I.

Abstract: The present disclosure inhibits liquid metal embrittlement (LME) cracking and improves corrosion resistance in a welded joint obtained by spot welding a first steel sheet and a second steel sheet. In the welded joint of the present disclosure, a first plating layer is provided on a surface of the first steel sheet facing the second steel sheet, no plating layer is present on or a second plating layer is provided on a surface of the second steel sheet facing the first steel sheet, a boundary plating layer is provided between the first steel sheet and the second steel sheet in a range of 0.5 mm from an end part of the corona bond of the spot welded part toward an outside of the spot welded part, and a Zn penetrated part is present at least at one of the first steel sheet and the second steel sheet adjoining the boundary plating layer.

Abstract: The hot-dip plated steel material includes a steel material and a hot-dip plated layer disposed on a surface of the steel material, the hot-dip plated layer has a certain chemical composition, and the hot-dip plated layer has a diffraction intensity obtained from a result of X-ray diffraction measurement, the diffraction intensity satisfying a certain relationship.

Abstract: The present disclosure inhibits liquid metal embrittlement (LME) cracking in a welded joint obtained by spot welding a first steel sheet and a second steel sheet. In the welded joint of the present disclosure, a first plating layer is provided on a surface of the first steel sheet facing the second steel sheet, no plating layer is present on or a second plating layer is provided on a surface of the second steel sheet facing the first steel sheet, and a boundary plating layer is provided between the first steel sheet and the second steel sheet in a range of 0.5 mm from an end part of the corona bond toward an outside of the spot welded part. A higher tensile strength of a tensile strength of the first steel sheet and a tensile strength of the second steel sheet is 780 MPa or more, an area ratio of a ?-Zn phase at the cross-section of the boundary plating layer is 5% or more, and the first plating layer and the second plating layer satisfy predetermined Relations I and II.

Abstract: A plated steel material having a plating layer having an average chemical composition containing, in mass %, Zn: more than 50.00%, Al: more than 15.0% and less than 30.0%, Mg: more than 5.0% and less than 15.0%, and Si: 0.25% or more and less than 3.50%, and impurities, and wherein a total amount (?A) of at least one selected from the group consisting of Sn, Bi and In is less than 1.00%, a total amount (?B) of at least one selected from the group consisting of Ca, Y, La, Ce and Sr is 0.02% or more and less than 0.60%, 2.0?SMg/Si<20.0 (Formula 1), 3.0?Si/?B<24.0 (Formula 2), and 26.0?(Si/?B)×(Mg/Si)<375.0 (Formula 3) are satisfied, and in an X-ray diffraction pattern of the surface of the plating layer, a diffraction intensity ratio R1 defined by R1={I(16.18°)+I(32.69°)}/I(27.0°) (Formula 4) satisfies 2.5<R1 (Formula 5) is used.

Abstract: This hot stamped member includes: a steel; and a plating layer formed on the steel, in which the plating layer has a predetermined chemical composition, the plating layer contains a Zn-based oxide including one or two of a Zn oxide and a Zn—Mg oxide having a size of 1.0 ?m or more and 10.0 ?m or less in a thickness direction of the plating layer and 0.1 ?m or more in a direction perpendicular to the thickness direction, and in a cross section of the plating layer in the thickness direction, when a length of an interface between the plating layer and the steel is indicated as Le, a sum of lengths of the Zn-based oxide projected onto the interface from an upper surface of the plating layer is indicated as ?Li, and a sum of lengths of portions of the Zn-based oxide in contact with the plating layer projected onto the interface from the upper surface of the plating layer is indicated as ?Lai, ?Li/Le?0.10 and ?Lai/?Li?0.50 are satisfied.

Abstract: This hot-dip Zn-based plated steel sheet includes a steel sheet and a plating layer formed on at least part of a surface of the steel sheet, in which the plating layer has a chemical composition that includes, by mass %, Al: 6.00% to 35.00%, Mg: 2.00% to 12.00%, Ca: 0.005% to 2.00%, Si: 0% to 2.00%, Fe: 0% to 2.00%, Sb: 0% to 0.50%, Sr: 0% to 0.50%, Pb: 0% to 0.50%, Sn: 0% to 1.00%, Cu: 0% to 1.00%, Ti: 0% to 1.00%, Ni: 0% to 1.00%, Mn: 0% to 1.00%, Cr: 0% to 1.00%, and a remainder: Zn and impurities, the plating layer has an area ratio of a MgZn2 phase in a range of 15% to 60% in a cross section in a thickness direction, and the MgZn2 phase includes a Ca-based intermetallic compound having a circle equivalent diameter of 0.10 ?m or smaller.