Influence of silicon content on high temperature tribology performance of TiAlCrSiN coatings.

A series of TiAlCrSi X N coatings with various silicon contents were fabricated on Si(100) and 304 stainless steel substrates using a radiofrequency magnetron sputtering system, aiming to examine the effects of various Si content on wear behaviors at room temperature and 700 °C. The addition of silicon notably increased the coatings' hardness from 21 GPa to 29 GPa, attributed to significant compressive residual stress (−3.4 GPa) that inhibited dislocation movement. Room temperature wear tests revealed that wear rates varied between 0.6 and 3.7 (10−6mm3N−1 m−1) with increasing silicon content. The lowest wear rate is observed at a silicon content of 3.1 at.%, which is associated with an ideal residual stress of −1.2 GPa. This stress level played a crucial role in preventing crack propagation and delamination, thus enhancing wear protection. At 700 °C, the coatings' wear resistance was mainly governed by their oxidation resistance, with the most resistant coatings exhibiting wear rates from 1.6 to 4.4 (10−6mm3N−1 m−1). The silicon addition promoted the formation of an amorphous Si 3 N 4 phase, serving as an oxygen diffusion barrier, thus enhancing resistance to oxidation at elevated temperatures. The findings suggest that TiAlCrSiN coatings offer a promising solution for advanced tribological applications, demonstrating improved performance at temperatures up to 700 °C. • Conducted high-temperature ball-on-disk wear tests to evaluate the wear resistance of (TiAlCrSi X)N coatings. • Explored the crucial role of residual stress in enhancing wear resistance at room temperature. • Demonstrated significant improvement in high-temperature wear resistance through silicon incorporation into (TiAlCr)N coatings. [ABSTRACT FROM AUTHOR]