The CrB Particles Reinforced MMC Coating was prepared by suing high velocity arc spraying (HVAS) method.Through a series of experiments,including metallograph,SEM and EPMA,the microstructure and composition of the coating were analyzed in details.The high temperature abrasion resistance of the CrB coating was studied through field test,which was done by depositing the coating on the surface of the water-wall tubes in a circulating fluidized bed boiler.After that,the abrasion resistance mechanism was also studied through the observation on the micro-appearance of the abrasion surface of the coating by using the SEM.The results show that the microstructure of the coating is typical compact structure with layer upon layer,like that of the composites,and each layer is composed of successive metal matrix.The hard particles are mainly compound of boron and chromium,others are oxide of chromium.The hard particles scatter evenly and dispersedly in the coating,which can reinforced the coating and play a role to hinder the movement of the abrasion particles.On the other hand,the metal matrix with well ductility and toughness can make buffer action to the impact caused by the abrasion particles.Therefore,the abrasion rate of the coating can be greatly slowed down and the coating will has excellent abrasion resistance.The results also show that the hardness,shape and quantity of the reinforced particles have magnificent influence to the abrasion resistance of the coating made in this paper.