Stainless steel 304 and 316 plates were deposited with multi-layered coatings of titanium films (0.1 μm) and gold films (1-2 μm) by an electron beam evaporation method. XRD patterns of the stainless steel plates modified with the multi-layered coatings showed the crystalline phases of the external gold film and the stainless steel substrate. Surface microstructural morphologies of the stainless steel bipolar plates modified with multi-layered coatings were observed by atomic force microscope (AFM) and field emission-scanning electron microscope (FE-SEM) images. The external gold films formed on the stainless steel plates showed the microstructure of grains of about 100 nm diameter. The grain size of the external surface of the stainless steel plates increased with the gold film thickness. The electrical resistivity and water contact angle of the stainless steel bipolar plates covered with multi-layered coatings were examined as a function of the thickness of the external gold film.

Keywords: Proton exchange membrane fuel cell (PEMFC), Bipolar plates, Gold film, Titanium film, Resistivity.