Numerical Simulation and Experimental Investigation of SiC/Ti-6Al-4V Metal Matrix Composites Produced by Laser Melt Injection

In this work, a 3D transient finite element (F.E.) model was established to investigate the temperature field distribution in laser processing of the Ti-6Al-4V substrate. The influences of laser power and scanning velocity on the molten pool state were analyzed. In an integrated model considering the length, temperature, and lifetime of the tail area of the molten pool, a laser power of 2.5 kW and a scanning velocity of 60 mm/s are thought to be suitable for laser melt injection. Particle reinforced metal matrix composite coating with a thickness of about 250 mu m was prepared on the Ti-6Al-4V surface under the above process. It was found that the microstructure and hardness of the coating gradient varied along the depth direction. The maximum hardness of the coating can reach 1729.5 HV, which is much higher than that of the Ti-6Al-4V substrate.