| abstract |
Provided is a titanium or titanium alloy for a solid polymer-type fuel cell separator having excellent contact resistance with carbon and durability. A titanium or titanium alloy oxide having a film formed by stabilization after passivation treatment on a titanium or titanium alloy substrate and, dispersed through this oxide film, particles having a major axis of 1 to 100 nm formed from one, two, or more conductors selected from carbides, nitrides, carbonitrides, and borides of tantalum, titanium, vanadium, zirconium and chromium is characterized in that the contact resistivity with carbon paper is 20 mΩ·cm 2 or less at a surface pressure of 10 kgf/cm 2 both before and after forced degradation tests involving immersion for four days in an aqueous sulfuric acid solution at 80ºC brought to a pH of 4. |