| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a solid polymer type fuel cell with excellent durability which low retains contact resistance over a long period and can maintain excellent conductivity even if the frequency of the stop and start is increased, and to provide a stainless steel suitable for being used as a separator thereof. <P>SOLUTION: The stainless steel for a solid polymer type fuel cell separator has a composition comprising, by mass%, 16 to 45% Cr, ≤3% Si, ≤3% Mn, ≤2% Ti, ≤2% V, ≤2% Zr, ≤2% Nb and ≤7% Mo, and in which Q value calculated by Q=[Cr]+[Si]+[Ti]+[V]+1.5([Zr]+[Nb]+[Mo])+0.5[W] exceeds 18 and a structure where the area ratio of a σ phase precipitated in the vicinity of the surface, so as to be exposed to the surface is ≥1%, and also, crystal grain sizes are ≥5.0 μm. <P>COPYRIGHT: (C)2010,JPO&INPIT |
