Characteristics and properties of plasma electrolytic nitrocarburizing Ti (C, N) coatings on Ti6Al4V alloy

Abstract

Abstract Titanium carbonitrides Ti(C,N) coatings were prepared by plasma electrolytic nitrocarburizing in an electrolytic solution containing ammonium nitrate, glycerol and ethanol. The coating consists of an outer compound layer and an inner diffusion layer with a total thickness of about 100μm. The compounds consist of Ti(C,N) and amorphous TiO2. The corrosion current density of the coating is almost an order of magnitude lower than that of Ti6Al4V substrate in 3.5% NaCl solution. The hardness of the coating is up to 2200HK0.025, which is 5~6 times greater than that of Ti6Al4V alloy. The coating itself is worn very slightly while the counter ball suffering serious abrasion during sliding against the SAE52100 counter ball. The PEN/C coating enhances the hardness, corrosion and abrasive resistances of Ti6Al4V alloy substantially.