The invention concerns a wheel hub bearing unit for a vehicle, said hub bearing unit comprising a rotating bearing ring member (1 ) and a non-rotating bearing ring member (2), where the rotating bearing ring (1 ) has at least a radially extending wheel mounting flange (4) with a reference flange surface (5); wherein a layer of an electrolytically sacrificial metal or metal alloy is provided by an electric arc spraying process on the flange surface (5).
