| 摘要 |
PROBLEM TO BE SOLVED: To provide excellent corrosion resistance, good electric conductivity and low contact resistance in a strong acid environment by including an impurity for imparting electric conductivity in a covering layer in a separator for a low temperature type fuel cell by forming the covering layer of conductive titanium oxide mainly composed of TiO2 on the surface by using stainless steel as a base material. SOLUTION: TiO2 substantially contains an unavoidable impurity mixed in a forming process, but the electric peroperty is a semiconductor, and an impurity metallic ion or a nonmetallic ion is actively introduced into a covering layer of titanium oxide to secure excellent electric conductivity. Electric conductivity of the covering layer increases by the introduction of a lattice defect, but since it is thermally unstable, an impurity ion is desirably added. The impurity is one kind or two or more kinds of Fe, Cr, Ni, Si, Mn, Mo, and Cu and the impurity is suitably one kind or two or more kinds of constitutive components of stainless steel diffused from a base material. |
