Abstract:
A method is provided for producing a hot-pressed member including heating a Ni-based coated steel sheet, which includes, on a surface thereof, a Zn—Ni alloy coating layer containing 13% by mass or more of Ni, in a temperature region of an Ac3 transformation point to 1200° C.; and then hot-pressing the steel sheet.
Abstract:
A hot-pressed member includes a steel sheet, a Ni-diffusion region present in a surface layer of the steel sheet, and an intermetallic compound layer and a ZnO layer which are provided in order on the Ni-diffusion region, the intermetallic compound layer corresponding to a γ phase present in a phase equilibrium diagram of a Zn—Ni alloy, wherein a spontaneous immersion potential indicated in a 0.5 M NaCl aqueous air-saturated solution at 25° C.±5° C. is −600 to −360 mV based on a standard hydrogen electrode.
Abstract:
Stainless steel sheets including a Ni and O-containing coating on the surface that has excellent weld penetration characteristics and excellent crevice corrosion resistance, and a method for producing such stainless steel sheets. A stainless steel sheet includes a Ni and O-containing coating on a surface of the stainless steel sheet. The Ni and O-containing coating has a coating weight of greater than or equal to 0.1 g/m2 and less than or equal to 20 g/m2. The Ni and O-containing coating has a composition including, in at. %, Ni: greater than or equal to 25% and less than or equal to 60%, and O: greater than or equal to 40% and less than or equal to 70%.
Abstract:
A method for producing a hot-pressed member includes heating a coated steel sheet, which includes, on a surface thereof, a Zn—Ni alloy coating layer containing 10% by mass or more and less than 13% by mass of Ni at a coating weight of over 50 g/m2 per side of the steel sheet, in a temperature region of an Ac3 transformation point to 1200° C. at an average heating rate of 12° C./second or more, and then hot-pressing the steel sheet.
Abstract:
A hot-pressed member includes a steel sheet, a Ni-diffusion region present in a surface layer of the steel sheet, and an intermetallic compound layer and a ZnO layer which are provided in order on the Ni-diffusion region, the intermetallic compound layer corresponding to a γ phase present in a phase equilibrium diagram of a Zn—Ni alloy, wherein a spontaneous immersion potential indicated in a 0.5 M NaCl aqueous air-saturated solution at 25° C.±5° C. is −600 to −360 mV based on a standard hydrogen electrode.
Abstract:
The present invention provides stainless steel sheets including a Ni and O-containing coating on the surface and having excellent weld penetration characteristics and excellent crevice corrosion resistance, and provides a method for producing such stainless steel sheets.A stainless steel sheet includes a Ni and O-containing coating on a surface of the stainless steel sheet. The Ni and O-containing coating has a coating weight of greater than or equal to 0.1 g/m2 and less than or equal to 20 g/m2. The Ni and O-containing coating has a composition including, in at. %, Ni: greater than or equal to 25% and less than or equal to 60%, and O: greater than or equal to 40% and less than or equal to 70%.
Abstract:
A hot-pressed member includes a steel sheet, a Ni-diffusion region present in a surface layer of the steel sheet, and an intermetallic compound layer and a ZnO layer which are provided in order on the Ni-diffusion region, the intermetallic compound layer corresponding to a γ phase present in a phase equilibrium diagram of a Zn—Ni alloy, wherein a spontaneous immersion potential indicated in a 0.5 M NaCl aqueous air-saturated solution at 25° C.±5° C. is −600 to −360 mV based on a standard hydrogen electrode.
Abstract:
A zinc-based metal plated steel sheet is excellent in tribological properties during press forming. An oxide layer containing crystalline 3Zn(OH)2·ZnSO4·xH2O is formed on a plated surface. The oxide layer has a thickness of 10 nm or more. The crystalline oxide layer is composed of 3Zn(OH)2·ZnSO4·3-5H2O.
Abstract:
A measuring apparatus is capable of measuring an amount of hydrogen penetrated into a metal. In the apparatus, a specimen formed of a metallic material has one surface exposed to a corrosive environment to serve as a penetration surface of hydrogen generated by a corrosion reaction while having the other surface as a hydrogen detection surface. On the hydrogen detection surface side, an electrochemical cell constituted of a plurality of cells is disposed. At least one of the plurality of cells is configured as a base cell to compensate for a residual current so that anodic currents detected in other cells than the base cell are compensated for based on the residual current detected in the base cell, and an amount of hydrogen penetrating from a corrosive surface side is calculated based on the compensated currents.
Abstract:
A hot-pressed member includes a steel sheet, a Ni-diffusion region present in a surface layer of the steel sheet, and an intermetallic compound layer and a ZnO layer which are provided in order on the Ni-diffusion region, the intermetallic compound layer corresponding to a γ phase present in a phase equilibrium diagram of a Zn—Ni alloy, wherein a spontaneous immersion potential indicated in a 0.5 M NaCl aqueous air-saturated solution at 25° C.±5° C. is −600 to −360 mV based on a standard hydrogen electrode.