Structure and wear resistance of duplex coating formed on VТ6 titanium alloy by combining diffusion nitriding and subsequent ion-plasma spraying with TiN and ZrN

The abrasive wear resistance of TiN and ZrN coatings on Ti–6Al–4V titanium alloy was investigated after preliminary saturation of its surface with nitrogen. The titanium plates were nitrided from the gas phase under a pressure of 105 Pa at a temperature of 750°С for 2 h. The TiN and ZrN coatings with a thickness of 30 μm were formed by the ion-plasma method using the “Bulat-3” equipment. The metallographic analysis showed that after diffusion nitriding, a TiN layer 1–3 μm thick and a layer of solid solution of nitrogen 100 μm thick were formed on the surface of the titanium plate. Nitriding of titanium plates with subsequent formation of TiN and ZrN ion-plasma coatings on these surfaces increased their abrasive wear resistance by 30%.