Abstract: Bipolar plate for assembling the elements of a fuel cell unit, consisting of a stainless-steel substrate (1) coated on at least one of the two faces thereof with a layer (5) of an electrically conductive material, characterised in that the material is selected from CrN and a bivalent or trivalent Ti compound or a mixture of such compounds, in that if the electrically conductive material is a bivalent or trivalent Ti compound or a mixture of such compounds, the layer (5) contains at most a quantity of oxygen in at. %, measured by X-ray photoelectron spectroscopy (XPS) on the upper 10 nm of the layer, which does not exceed 1.5 times the content in at. % of oxygen which, according to the measured content in at.

Abstract: The present invention relates to a method for manufacturing a metal strip or sheet, including the steps of providing a substrate made from stainless steel; and depositing a chromium-nitride layer on the substrate by physical vapor deposition (PVD) in a deposition installation comprising a deposition chamber and a chromium target arranged in the deposition chamber. The deposition chamber has a deposition area with a length strictly smaller than the length of the deposition chamber and at least a first prohibited area. During the deposition, the chromium nitride is deposited on the substrate only in the deposition area and no chromium nitride is deposited on the substrate in the prohibited area.

Abstract: The present invention relates to a metal strip or sheet comprising a substrate made from stainless steel covered with at least one layer of a chromium-nitride coating. The chromium-nitride coating layer is textured.