The Principle and Micro-structure of Gradient Liquid Phase Sintering of Thermal Spray Coating

In this paper, the non-synchronous phenomenon of temperature distribution in space and time in compact metal-power sintering are discussed, it indicate that the gradient design for thermal spray coating sintering is necessary. The basic condition of gradient liquid phase sintering, the microstructure and the poperty of coating bonding are discussed.The results show that the liquid phase sintering necessary for coating stability can be realized by gradient designing, the viscous flow of ordinary liquid phase sintering can be avoided, the oxide in micro-structure tend to assembling, and there is a clear liquid-solid phase boundary line in the surface of coating.