Improved high-temperature tribological properties of Ti3SiC2 modified NiCr-Cr3C2 coatings and their wear mechanism

In light of the mounting concerns surrounding global energy consumption, there is a growing focus on the development of composite coatings that are capable of regulating friction and wear, and possess self-lubricating and self-healing properties. NiCr-Cr3C2-Ti3SiC2 composite coatings were prepared by atmospheric plasma spraying, and the phase compositions, microstructures, microhardness, porosity and tribological properties (friction coefficient and wear rate) of the coatings were investigated. Specific focus was dedicated to the investigation of wear mechanisms at elevated temperatures. The findings reveal that the coating with 15 wt% Ti3SiC2 (15TiSiC) exhibits the lowest friction coefficient (0.395) and wear rate (1.55 x 10-5 mm3 N-1 m-1) among all the samples at 800 degrees C. The wear mechanism can be categorized as follows: at room temperature, fatigue wear and abrasive wear; at 200 and 400 degrees C, adhesive wear and abrasive wear; and at 600 and 800 degrees C, adhesive wear and oxidative wear.