Microstructure evolution and high-temperature tribological behavior of Ti3SiC2 reinforced Ni60 composite coatings on 304 stainless steel by laser cladding

A series of composite coatings (Ni60-Ti3SiC2) were prepared by laser cladding on 304 stainless steel (SUS304). Then the tribological properties were investigated at room temperature (RT) and 600 °C. From the results, because of the fine-grain and dispersion strengthening caused by the presence of small-sized hard phases, the hardness of coatings was much higher than substrate. Benefiting from the addition of Ti3SiC2 lubricant, the friction reduction and wear resistance were decreased greatly, especially the wear rate and friction stability were enhanced 88.9% and 61.5% respectively at the high temperature. The wear mechanisms changed from serious oxidation adhesive wear on the substrate to the slight abrasive wear under the auxiliary lubrication of oxide films and Ti3SiC2 on the composite coatings.