Patent ID: 9040166
Filing Date: 2015-05-26
Classification: B21D,B32B,C21D,C22C,C23C,C25D,Y10T

Abstract:
1. A hot-pressed member that is produced by heating and then hot-pressing a Ni-based coated steel sheet, wherein the Ni-based coated steel sheet includes, on a surface thereof, (i) a Zn—Ni alloy coating layer containing 13% by mass or more of Ni, or (ii) 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/m wherein the hot-pressed member that is produced by heating and then hot-pressing the Ni-based coated steel sheet comprises a Ni-diffusion region that is present in a surface layer of the steel sheet, and an intermetallic compound layer and a ZnO layer which are provided such that the intermetallic compound layer is provided on the Ni-diffusion layer and the ZnO layer is provided on the intermetallic compound layer, the intermetallic compound layer comprising a γ phase present in a phase equilibrium diagram of a Zn—Ni alloy, and 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.