The plasma arc surfacing technology of wear-resistant materials adopts the plasma arc surfacing method, which takes advantage of the high temperature and high current density of the plasma arc. The composite surfacing layer is composed of more than two kinds of dissimilar materials with different properties in macroscopic view. One is carbide hard particles which play an important role in wear resistance in the surfacing layer, which are generally cast tungsten carbide, chromium carbide and boron carbide, In principle, all kinds of carbides, borides and even diamond with higher hardness can be used as the components of the composite surfacing layer. The hard particles used in plasma arc surfacing of composite materials at home and abroad are cast tungsten carbide, which is composed of eutectic components with hardness of 250-300. The other composition metal of surfacing layer is the base metal which plays the role of "bonding" It is generally believed that the combination of hard particles and matrix metal is brazing bonding, and the bonding between surfacing layer and base metal is metallurgical bonding.