Tribological behavior of TiAlN-coated TA19 alloy at elevated temperatures

TiAlN coating was deposited through the magnetron sputtering technology on the TA19 titanium alloy. The microstructure, composition, and binding force of the TiAlN coating were systematically evaluated. The friction and wear performance of coated specimens at elevated temperature were studied in detail. For elastic modulus E, the values of hardness H, H/E, and H3/E2 of the TiAlN coating were much higher than those of the matrix, which directly reduced the friction coefficient, wear volume, and wear rate of the TiAlN coating in high-temperature friction and wear. The friction mechanism of matrix and coating was mainly abrasive wear at room temperature. However, the coating and matrix suffered from tribo-oxidation at 300 and 500°C. In the process of friction and wear, the coating had no obvious characteristics of spalling and mechanical failure, showing good abrasive resistance at high temperature. This makes the TiAlN coating an effective high-temperature protective coating for titanium alloys.