SOLID POLYMER ELECTROLYTE TYPE FUEL CELL-USE SEPARATOR AND PRODUCTION METHOD THEREFOR

摘要

A stainless steel−made separator, especially, a solid polymer electrolyte type fuel cell−use separator having both high corrosion resistance and high conductivity, and a production method therefor. The solid polymer electrolyte type fuel cell−use separator is formed by coating the surface of stainless steel having a general corrosion index, GI=[Cr%]+3.6[Ni%]+4.7&lsqb ;Mo%]+11.5[Cu%], of at least 90 with a conductive compound such as metal nitride and metal−dispersed diamond−like carbon. When forming a coating, ion bombarding is conducted on the surface of the above high−corrosion−resistance stainless steel as a pre−treatment, and then a conductive compound is applied by ion plating. High corrosion resistance and high conductivity are ensured by this surface coating at coated portions, and high corrosion resistance is supported by the passive coating of stainless steel itself at non−coated portions (defective portions such as pin holes).