Abstract: Provided is a Zn—Al—Mg—Si coated steel sheet that has excellent chemical convertibility, suppression of under-coat blistering, and dissimilar joined portion corrosion resistance. The Zn—Al—Mg—Si coated steel sheet includes a base steel sheet and a coated layer formed on at least one surface of the base steel sheet. The coated layer has a chemical composition as described in the description and a Zn—Al—MgZn2 ternary eutectic alloy structure. In a reflected electron image at a magnification of 5000 times obtained with a scanning electron microscope at an accelerating voltage of 7.0 kV, a needle-like Mg2Si alloy phase is present in the ternary eutectic alloy structure at a number density of less than 100,000/mm2, and at an accelerating voltage of 15.0 kV, the needle-like Mg2Si alloy phase is present at a number density of 500/mm2 or more and a needle-like SiO2 oxide phase is present at a number density of 100,000/mm2 or more.

Abstract: A hot pressed member includes: a steel material; an Al—Fe-based intermetallic compound layer with a thickness of 10 ?m to 30 ?m disposed on at least one side of the steel material; and Mg-containing oxide particles disposed on the Al—Fe-based intermetallic compound layer, wherein the Mg-containing oxide particles have an average particle size of 5.0 ?m or less and a number density of 1000 particles/mm2 or more.

Abstract: A hot-pressed member having excellent post-coating corrosion resistance and excellent resistance spot weldability, a method for manufacturing the hot-pressed member, and a steel sheet for hot pressing suitable for a hot-pressed member having excellent post-coating corrosion resistance and excellent resistance spot weldability. The hot-pressed member includes a Zn-based coated layer on a first side of a steel sheet, and a Zn-based coated layer on a second side of the steel sheet. A coating weight of Zn in the Zn-based coated layer on the first side of the steel sheet is 5 to 35 g/m2, and an average line roughness Ra of a surface of the Zn-based coated layer on the first side is less than or equal to 2.5 ?m. The average line roughness Ra of a surface of the Zn-based coated layer on the second side of the steel sheet is greater than or equal to 3.5 ?m.

Abstract: A steel sheet for hot press forming that can reduce diffusible hydrogen content introduced in hot press forming without controlling the atmosphere dew point, and may be used to obtain a hot pressed member that has excellent post-coating corrosion resistance. The steel sheet includes a base steel sheet and a coated layer on both sides of the base steel sheet. The coated layer has a chemical composition containing Si: 7 mass % to 11 mass %, Mg: 0.6 mass % to 1.9 mass %, one or both of Ca and Sr: in total, 1.0% to 10% of Mg, and Fe: 0 mass % to 30 mass %, with the balance being Al and inevitable impurity. Concentration of Mg solute in Al phase in the coated layer is less than 1 mass %, and average thickness of the coated layer is 10 ?m to 30 ?m on each side of the base steel sheet.

Abstract: Achieved are both corrosion resistance at cut portion and spot weldability at a high level in a hot pressed member with an Al—Zn coating layer, which does not have the chemical convertibility problems of an Al coated or plated steel sheet or the LME cracking problems of a Zn coated or plated steel sheet. The hot pressed member includes a steel sheet, a coating layer on at least one side of the steel sheet, and an oxide layer on the coating layer. The coating layer has a chemical composition containing, in mass %, Zn: 25.0% to 55.0%, Si: 1.1% to 8.0%, Sr+Ca: 0.01% to 5.0%, and Fe: 55.0% or less, with the balance being Al and inevitable impurity. The coating layer contains a metallic Zn phase.

Abstract: A hot-pressed member is disclosed including at least one surface that has a filtered centerline waviness Wca of less than or equal to 1.5 ?m.

Abstract: Provided is a steel sheet for hot pressing that has excellent suitability for high-speed heating, resists liquid metal embrittlement cracking, and has excellent paint adhesion after hot pressing. A steel sheet for hot pressing comprises: a base steel sheet; and a coating layer of 0.5 ?m to 6.0 ?m in thickness provided on both sides of the base steel sheet, wherein the coating layer is made of Ni or a Ni-based alloy, and a Zn content in the coating layer is 0 mass % to 30 mass %.

Abstract: Provided is a hot pressed member for which an amount of hydrogen entering during the hot press process is small, that can release hydrogen that has entered in a short period of time, and that has excellent delayed fracture resistance. The hot pressed member includes: steel material; an Al—Fe intermetallic compound layer having a thickness of 10 ?m to 35 ?m, on at least one side of the steel material; and a diffusion layer at an interface between the Al—Fe intermetallic compound layer and the steel material. The Al—Fe intermetallic compound layer includes an Al-rich phase having an Al concentration of 40 mass % or more and an Fe-rich phase having an Al concentration of less than 40 mass %. Average length of the Fe-rich phase in a cross-section in a direction perpendicular to the thickness direction is 10 ?m or less.

Abstract: Provided is a hot pressed member having excellent spot weldability and corrosion resistance at cut portion. The hot pressed member includes a steel sheet, a coating layer on at least one side of the steel sheet, and an oxide layer having a thickness of 1.0 ?m or less on the coating layer. The coating layer has a chemical composition containing, in mass %, Zn: 5.0% to 55.0%, Si: 1.1% to 8.0%, Mg: 2.0% to 6.0%, Sr: 0.01% to 2.0%, and Fe: 55.0% or less, with the balance being Al and inevitable impurity.

Abstract: Provided is a hot pressed member with excellent post-painting corrosion resistance and excellent corrosion resistance at lapped part. The hot pressed member includes: a steel material; an Al—Fe-based intermetallic compound layer with a thickness of 10 ?m to 30 ?m disposed on at least one side of the steel material; and Mg-containing oxide particles disposed on the Al—Fe-based intermetallic compound layer, wherein the Mg-containing oxide particles have an average particle size of 5.0 ?m or less and a number density of 1000 particles/mm2 or more.

Abstract: A hot pressed member that has excellent corrosion resistance after coating, in particular when a zirconium chemical conversion treatment is applied, and with reduced microcracks. The hot pressed member includes a steel sheet, a coated or plated layer containing FeAl, Fe2Al5, and Zn distributed over at least one side of the steel sheet, and a Zn-containing oxide layer distributed over the coated or plated layer. The solute Zn content in the FeAl is less than 10 mass %.

Abstract: For a steel sheet for hot pressing having a coating layer to prevent scale formation, adhesion of metals to heating equipment is reduced, liquid metal embrittlement cracking during hot press forming is prevented, and excellent post-painting corrosion resistance is achieved. A coated steel sheet for hot pressing includes: a base steel sheet; and a coating layer of 7 ?m to 20 ?m in thickness provided on both sides of the base steel sheet, wherein the coating layer is made of Ni or a Ni-based alloy, and a Zn content in the coating layer is 0 mass % to 10 mass %.

Abstract: A steel sheet for hot press forming that can reduce diffusible hydrogen content introduced in hot press forming without controlling the atmosphere dew point, and may be used to obtain a hot pressed member that has excellent post-coating corrosion resistance. The steel sheet includes a base steel sheet and a coated layer on both sides of the base steel sheet. The coated layer has a chemical composition containing Si: 7 mass % to 11 mass %, Mg: 0.6 mass % to 1.9 mass %, one or both of Ca and Sr: in total, 1.0% to 10% of Mg, and Fe: 0 mass % to 30 mass %, with the balance being Al and inevitable impurity. Concentration of Mg solute in Al phase in the coated layer is less than 1 mass %, and average thickness of the coated layer is 10 ?m to 30 ?m on each side of the base steel sheet.

Abstract: A hot pressed member that has excellent appearance quality after coating and corrosion resistance at cut portion. The hot pressed member includes a steel sheet, a coated or plated layer containing FeAl, Fe2Al5, and Zn distributed over at least one side of the steel sheet, and a Zn-containing oxide layer distributed over the coated or plated layer. The solute Zn content in the Fe2Al5 is 10 mass % or more.

Abstract: A hot-pressed member, a steel sheet for hot pressing, and methods for producing the hot-pressed member and the steel sheet for hot pressing. The hot-pressed member includes a steel sheet and a Zn-based alloy coated layer disposed on at least one surface of the steel sheet. The Zn-based alloy coated layer includes a solid solution phase including Zn with the balance being Fe and incidental impurities, an intermetallic compound phase including Fe with the balance being Zn and incidental impurities, and an oxide layer including Zn. The oxide layer serves as an uppermost layer of the Zn-based alloy coated layer and splits the intermetallic compound phase. The split density in at least one cross-section of the oxide layer per unit cross-section is 10 split positions/mm or more.

Abstract: A spot welded member includes a spot weld formed by holding a sheet stack of multiple steel sheets between a pair of electrodes and spot-welding the sheet stack, in which at least one of the multiple steel sheets is a high-strength zinc-based coated steel sheet having a tensile strength of 780 MPa or more, the high-strength zinc-based coated steel sheet having a coating with an Al content of 0.5% or more by mass, and in which the heat shock region of the spot weld outwardly extending from an edge of a corona bond area includes a coated layer including an FeAl alloy layer having an average thickness of 0.3 ?m or more and a zinc-based coated layer having an average thickness of 2.0 ?m or more on the FeAl alloy layer at the interface between the base steel sheet of the high-strength zinc-based coated steel sheet and the coating.

Abstract: A hot-pressed member is disclosed including at least one surface that has a filtered centerline waviness Wca of less than or equal to 1.5 ?m.

Abstract: A hot-pressed member having excellent post-coating corrosion resistance and excellent resistance spot weldability, a method for manufacturing the hot-pressed member, and a steel sheet for hot pressing suitable for a hot-pressed member having excellent post-coating corrosion resistance and excellent resistance spot weldability. The hot-pressed member includes a Zn-based coated layer on a first side of a steel sheet, and a Zn-based coated layer on a second side of the steel sheet. A coating weight of Zn in the Zn-based coated layer on the first side of the steel sheet is 5 to 35 g/m2, and an average line roughness Ra of a surface of the Zn-based coated layer on the first side is less than or equal to 2.5 ?m. The average line roughness Ra of a surface of the Zn-based coated layer on the second side of the steel sheet is greater than or equal to 3.5 ?m.

Abstract: A hot-pressed member, a steel sheet for hot pressing, and methods for producing the hot-pressed member and the steel sheet for hot pressing. The hot-pressed member includes a steel sheet and a Zn-based alloy coated layer disposed on at least one surface of the steel sheet. The Zn-based alloy coated layer includes a solid solution phase including Zn with the balance being Fe and incidental impurities, an intermetallic compound phase including Fe with the balance being Zn and incidental impurities, and an oxide layer including Zn. The oxide layer serves as an uppermost layer of the Zn-based alloy coated layer and splits the intermetallic compound phase. The split density in at least one cross-section of the oxide layer per unit cross-section is 10 split positions/mm or more.

Abstract: A ferritic stainless steel sheet comprises a chemical composition containing, in mass %, C: 0.030% or less, Si: 3.0% or less, Mn: 1.0% or less, P: 0.040% or less, S: 0.010% or less, Cr: 11.0% to 30.0%, Al: 8.0% to 20.0%, Ni: 0.05% to 0.50%, N: 0.020% or less, and at least one selected from the group consisting of Zr: 0.01% to 0.20% and Hf: 0.01% to 0.20%, with a balance consisting of Fe and inevitable impurities.