Wear performance of layered (TiNb)C reinforcement in surface of TiNb alloy

Abstract Deficiency in the wear resistance of TiNb alloy makes it necessary to enhance the surface properties of the alloy. Herein, in-situ solid-state carburization reaction (ISSCR) was used to produce (TiNb)C surface-reinforced layer (SRL), which can provide high surface wear resistance. The relationships between microstructure, hardness, elastic modulus, and tribology properties were investigated. The SRL has layered structure, in which the outer layer has higher hardness and lower elastic modulus than that of inner layer, the average hardness of SRL is about 31.74 GPa that is 7.38 times as that of the TiNb substrate. The ball on disc unlubricated sliding wear tests indicate that the wear rates of the SRLs range from 2.1 × 10−7 to 3.3 × 10−7 g/m, but the wear rate of the substrate is about 516.3 × 10−7 g/m. With the change of load and sliding time, the outer layer of SRL present delamination under load of 10 N and spalling pits under load of 20 N, both of which are indications of surface fatigue wear; further, the inner layer of SRL present micro-cutting wear caused by of two-body abrasion under load of 20 N. The outstanding wear resistance of SRL will significantly protect the integrality of TiNb substrate.