Surface modification of TC4 Ti alloy by laser cladding with Ni-Ti-Nb powders

TC4 Ti alloy with the excellent properties can be applied to many fields, but the surface performance such as wear-resisting, fretting wear, contact corrosion etc.can't be met for many special demands. Laser cladding was applied on a TC4 Ti alloy to improve its properties. Mixed Ni,Ti and Nb powders were put onto the TC4 Ti alloy and subsequently treated by laser beam. The experimental results show that the surface hardness and wear resistance are significantly improved. The increase in wear resistance is predicted to be related to the "adaptive" wear mechanism of SMA.The microstructure and composition modifications in the surface layer were carefully investigated by using SEM, EDX and metallographic microscope. Experimental analyses show that the compositions of laser cladding coating are close to shape memory alloy of 44Ni-47Ti-9Nb,and differedt microstructure are rich with different elements. These experimental results are associated with laser processing techniques and alloy composition to some extent