Effect of SiC ceramic nano-particles on microstructure and tribological performance of the AlTiVNbNi refractory high entropy alloy in a wide temperature range

A novel Al_0.8TiVNbNi_0.2(SiC)_0.2 RHEA-based composite was fabricated by spark plasma sintering. The microstructure evolution and distinctions in high-temperature tribological properties of composite incorporating SiC nano-particles were systematically analyzed. The results demonstrate that SiC particles undergo in-situ reactions with the matrix alloy during the sintering process, resulting in the formation of TiC and Nb₅Si₃ phases, which significantly increases the microhardness of the composite. Simultaneously, wear resistance of Al_0.8TiVNbNi_0.2(SiC)_0.2 composite is sharply ameliorated in a wide temperature range (RT to 800 °C). The non-exogenous matching interface between reinforced phases and matrix is the key to good tribological performance. For another, the generated Si oxides is contribute to continuity of the tribo-layer formed at high-temperatures, leading to a conspicuous reduction of wear rates.