Microstructure and properties of TC4 laser cladding coating on Ti811 titanium alloy surface

According to the proposal of CFM56 series engine maintenance manual, the fine coating without pores and cracks was prepared by laser cladding with TC4 powders with coaxial powder synchronous feeding on the surface of Ti811 alloy. The macroscopic morphology, microstructure and phase transformation of the coating were analyzed, and the microhardness and wear friction properties of the coating were tested. The results indicated that the microstructure of the coating showed an obvious widmanstatten structural characteristic under scanning electron microscopy; the microhardness of the coating was improved compared with that of the substrate. The main reason was that the acicular martensite α' in the coating had a certain strengthening effect on the coating; at the same time, the precipitation strengthening and dispersion strengthening of nanoparticles Ti₃Al dispersing in the coating improved the microhardness to a certain extent. The wear mechanism of laser cladding layer was abrasive wear and adhesive wear.