Patent ID: 9680162
Date: 2017-06-13
CPC Classifications: C22C,H01M,Y02E

Claim:
1. A stainless steel member for a separator for a solid polymer fuel cell, the stainless steel base metal comprising: a stainless steel base metal; a passive film; and smut; wherein the passive film, which is a film of an electrically insulating oxide. and the smut are provided on a surface of the stainless steel base metal; wherein the smut is a substance, originating from the stainless steel base metal, which has precipitated on or adhered to the surface of the stainless steel member as a result of pickling of the stainless steel base metal; wherein the smut includes electrically conductive precipitates; wherein a thickness of the smut is larger than a thickness of the passive film and the electrically conductive precipitates penetrate the passive film; and wherein the passive film partially covers the smut on a surface of the stainless steel base material.