Effect of laser remelting on erosion resistance of plasma sprayed Al₂O₃-40% TiO₂ coating

The Al₂O₃-40% TiO₂ coating was made by plasma spraying, and remelted laser beam. The erosion resistance of plasma sprayed coating and laser remelted coating were tested respectively, and the effect of laser remelting on erosion resistance of plasma sprayed Al₂O₃-40% TiO₂ coating was studied. The results show that the layered structure of plasma sprayed Al₂O₃-40% TiO₂ coating can be changed by the laser remelting. The γ-Al₂O₃ phase transforms into α-Al₂O₃, and the laser remelted coating exhibits a stable structure which consists of α-Al₂O₃ and TiAl₂O₅. A compact, uniform, highly hard and good metallurgical bonded Al₂O₃-40% TiO₂ coating can be obtained. The erosion resistance of the plasma sprayed coating has been greatly improved by laser remelting, and the wear characteristics caused by the erosion sand particles are crack, crush and block desquamation.