FERRITIC STAINLESS STEEL EXCELLENT IN CORROSION RESISTANCE AND CONDUCTIVITY AND METHOD FOR MANUFACTURING THE SAME, SEPARATOR OF PROTON-EXCHANGE MEMBRANE FUEL CELL AND PROTON-EXCHANGE MEMBRANE FUEL CELL

摘要

A ferritic stainless steel excellent in corrosion resistance and conductivity and a method for manufacturing the same, the stainless steel having a chemical composition containing, by mass %, C: 0.001% or more and 0.05% or less, Si: 0.001% or more and 0.5% or less, Mn: 0.001% or more and 1.0% or less, Al: 0.001% or more and 0.5% or less, N: 0.001% or more and 0.05% or less, Cr; 17% or more and 23% or less, Mo: 0.1% or less and the balance being Fe and inevitable impurities and a passivation film on the surface of the stainless steel which is obtained by immersing the stainless steel in a solution for an immersion treatment, said solution mainly contains hydrofluoric acid or a liquid mixture of hydrofluoric acid and nitric acid.