Metal double-polar board of solid polymer dielectric film fuel cell and making method therefor

This invention relates to a metal double-pole plate of a solid polymer electrolyte film fuel battery and its preparation method, in which, the multifunction component-metal double-pole plate is composed of an iron-base alloy matrix and a surface modification layer with high surface conductivity and fine corrosion resistance, in which, the modification layer is a single phase and a nitride alloy, the Ni elements are reduced from the surface to the matrix steadily and the thickness of the layer is 0.1-3mm.