Stainless steel plate for polymer electrolyte fuel cell separator, method for producing the same, and polymer electrolyte fuel cell separator using the same

摘要

PPROBLEM TO BE SOLVED: To provide an austenitic stainless steel plate and its manufacturing method having a moldability necessary as a solid polymer fuel cell separator material. PSOLUTION: The solid polymer fuel cell separator, with an average crystal particle size of 0.25 mm or less, a difference between a Vickers hardness Hc at the center part of a plate thickness and a Vickers hardness Hs at 1/8 of the plate thickness from the surface of 20 or less, and a ductility in a rolling direction and a vertical direction of 65% or more, contains C: 0.07% or less, Si: 0.1 to 2.0%, Mn: 0.1 to 2.0%, P: 0.04% or less, S: 0.005% or less, Al: 0.2% or less, N: 0.050% or less, Cr: 16.0 to 18.5%, Ni: 6.0 to 15.0%, in mass%, with the rest consisting of Fe and inevitable impurities. Here, in the manufacturing method, heat treatment during cold rolling and after a final cold rolling are carried out under a furnace atmosphere with a nitrogen concentration of less than 1.0%, and the steel plate is cooled after keeping it at 1,050 to 1,150C within one minute. PCOPYRIGHT: (C)2006,JPO&NCIPI