Corrosion and corrosion-wear studies on WC cermet coatings were performed in a strong acid (5 wt. percent H_2SO_4) solution. Four different coating compositions such as WC-Co. WC-NL WC-Co-Cr, and WC-CrC-Ni were used. An immersion test and an electrochemical test results showed galvanic corrosion ocurred between WC particle/binder metal in the coating layers end general corrosion of metallic binder for the WC-Co arid WC-Ni coatings. Due to formation of beneficial chromium oxide on the coating surface, the best corrosion resistant and corrosion-wear properties were observed in the WC-Co-Cr coating. For the WC-CrC-Ni costing, the corrosion resistance depended on small INTER-connected cracks in the coating layer.
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