SEPARATOR FOR SOLID POLYMER FUEL CELL AND METHOD FOR MANUFACTURING THE SAME

摘要

This invention provides a separator for a solid polymer fuel cell in which the surface of the fuel cell separator has low resistance of contact with carbon paper and has excellent flatness, and a method for manufacturing the same. The separator for a solid polymer fuel cell comprises a base material of stainless steel or titanium or titanium alloy having a surface layer part with electroconductive compound particles fixed thereonto. The electroconductive compound particles are formed of one or at least two materials selected from metal borides, metal carbides, and metal nitrides, having an average particle diameter of 0.01 to 20 µm. The electroconductive compound particles are present in a region extended from the base material surface to a depth of 10 µm from the surface. In the region, the concentration distribution of the metal element constituting the electroconductive compound satisfies the requirement that the following relationship between the concentration C of the metal element constituting the electroconductive compound and the depth x from the base material surface is satisfied: formula (C = A · exp(-x/t) + B) and formula (10 = A = 90, -4.0 = B = 1.0 and 0.5 = t = 4.0).