To provide an inexpensive stainless steel which has corrosion resistance in a cell environment and also does not deteriorate the performance of a cell due to the elution of metal ions, as a metallic material composing a collector and a separator composing a methanol reformed fuel cell or the like, and to provide a method for producing the stainless steel.
The stainless steel for a cell composing member includes, by mass, 16.0 to 32.0% Cr, 0.5 to 2.0% Mo, 0.015% C, 0.5% Si and 2.0% Mn, and the balance Fe with inevitable impurities, and is characterized in that the surface layer of the stainless steel is provided with a passive film of 4 nm which satisfies, by atomic%, Cr/(Cr+Fe)0.2 and also CrOOHCr2O3. The method for producing the stainless steel uses immersion treatment to a solution containing organic acid and nitric acid or electrolytic treatment where potential of 700 to 900 mV, SCE is applied in a solution containing sulfuric acid.
TOMIMURA HIROKI
| JP2000256808A | 2000-09-19 | |||
| JP2004149920A | 2004-05-27 |
| WO2005073423A1 | 2005-08-11 |
Hidetoshi Furukawa
Suzuki Kenchi
Kajinami order
Kazuhiro Oyaku
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