| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a separator made of stainless steel for a polymer electrolyte fuel cell, capable of suppressing increase of contact resistance over a long time and exhibiting superior corrosion resistance. <P>SOLUTION: This separator made of stainless steel is formed, by using ferrite-based stainless steel containing 15-40 mass% of Cr and 1-5 mass% of Mo as a base material. In the separator, a passive coating, satisfying the atom number ratio Mo/(Mo+Cr+Fe) of Mo, Cr and Fe included in the passive coating as oxides and hydroxides, to be not larger than 0.3 and is 1.5 times as much as that of the base material is produced on the surface of the base material. The passive coating formed by concentrating Mo is formed through an immersion process by using a non-oxygenated acid solution. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
