Effect of PVD Nitride Coating Deposition on the High-Temperature Pin–Disc Friction Properties Between WC/Co Carbide and Ti2AlNb Alloy

Suitable nitride coating deposition could improve the wear resistance of WC/Co carbide tools when cutting Ti2AlNb typical difficult-to-machine alloy. However, there is no clear conclusion on which nitride series coating is suitable for improving the friction characteristics between WC/Co carbide and Ti2AlNb alloy. In this research, the CrAlN, CrAlN/(CrAlB)N/CrAlN, and TiAlN/ZrN coatings were deposited on WC/Co carbide with the only variable of coating type, which were utilized to conduct the high-temperature pin disc experiments with Ti2AlNb alloy at 600 °C, respectively. The high-temperature friction characteristics were analyzed by the friction coefficient with time, the alloy wear rate, the surface morphology, and element distribution after wear. The results showed that the three types of coating all improved the high temperature friction and wear characteristics of WC/Co carbide. The Ti2AlNb alloy also exhibited good surface morphology after wear with TiAlN/ZrN-coated carbide. It is speculated that TiAlN/ZrN coating was the suitable coating deposition on WC/Co carbide tools to improve cutting performance of Ti2AlNb alloy.