Titanium or titanium alloy material for fuel cell separator having high contact conductivity with carbon and high durability, fuel cell separator including the same, and manufacturing method therefor

A manufacturing method for a titanium or titanium alloy material for a fuel cell separator, the manufacturing method comprising:

• adding one or more kinds of conductive materials selected from carbide, nitride, carbonitride, and boride of tantalum, titanium, vanadium, zirconium, and chromium to a surface of a titanium or titanium alloy substrate, and then performing passivation treatment in which the substrate is immersed in an aqueous solution obtained my mixing one or more selected from 5 mass % or more nitric acid, 1 mass % or more chromic anhydride, and 5 mass % or more sulfuric acid;
• and then
• performing stabilization treatment in which the substrate is immersed in an aqueous solution at 60° C. or more to which one or more selected from 1 mass ppm or more rice flour, wheat flour, potato starch, corn flour, soy flour, amine-based compounds, aminocarboxylic-acid-based compounds, phospholipid, a commercially available acidic corrosion inhibitor, calcium ions, polyethylene glycol, and starch are added.