Friction–wear performances and oxidation behaviors of Ti3AlC2 reinforced Co–based alloy coatings by laser cladding

Abstract Ti3AlC2 reinforced Co–based alloy coatings were fabricated on H13 steel using a laser cladding (LC). The morphologies, chemical elements and phases of obtained coatings was analyzed using a scanning electron microscope (SEM), energy dispersive spectroscope (EDS), and X–ray diffraction (XRD), respectively. The effects of Ti3AlC2 mass fraction on the microstructure and friction–wear performances at 600 °C were investigated, and the wear mechanism was also discussed. The results show that the average coefficients of friction (COFs) of Co–based alloy coatings decrease with the increase of Ti3AlC2 mass fraction, exhibiting the excellent friction reduction. The continuous friction layer is formed by the Ti3AlC2 and oxidation products of Co–based coatings at high temperature, which is the main factor of friction reduction. The wear rate of Co–based–5%Ti3AlC2 is the lowest among the three kinds of coatings, the wear mechanism is combined of oxidative wear, adhesive wear and abrasive wear. The O contents of Co-based alloy coatings increase with the increase of Ti3AlC2 mass fraction, which are less than 3% at 600 °C, presenting the outstanding oxidation resistance.