Particle Variations and Effect on the Microstructure and Microhardness of Ti6al4V Hybrid Metal Matrix System

Manufacture of hybrid Ti6Al4 V alloy systems for application specifically in hot parts of turbine engines has been a challenge in recent years. This is due to the need to increase efficiency and reduce combustion rate and emission. In this work, three reinforcement powders namely Ti6Al4 V, B4C and BN were fed through three different hopper systems to create a melt pool on the surface of Ti6Al4 V alloy substrate. Three percentage variations of these powders with equal amount of B4C and BN were obtained as follow: 3.0 Ti6Al4 V, B4C and BN, 3.2 Ti6Al4 V, B4C and BN, and 3.4 Ti6Al4 V, B4C and BN systems. Laser coating experiment was done at 1400W. The influence of difference in variation of powder on the microstructure and hardness values was investigated. The hardness value improved significantly in the following order. 971.1 HV0.5, 971.1 HV0.5 and 1161.8 HV0.5 respectively. The overall coatings of layers were characterized by good microstructural homogeneity, excellent bonding with a metal substrate.