激光重熔对Al2O3-40% TiO2等离子喷涂层耐冲蚀性能的影响

利用等离子喷涂方法制备Al₂O₃-40% TiO₂涂层，对涂层进行激光重熔处理.分别对等离子喷涂层和激光重熔涂层进行耐冲蚀磨损性能试验，研究了激光重熔对Al₂O₃-40% TiO₂等离子喷涂层耐冲蚀性能的影响.结果表明，激光重熔消除了Al₂O₃-40% TiO₂等离子喷涂层的层状结构，使得等离子喷涂层中γ-Al₂O₃转变为α-Al₂O₃，形成了α-Al₂O₃+TiAl₂O₅稳定结构.激光重熔后的涂层组织致密均匀、硬度高，具有冶金结合特征，使得耐冲蚀性能得到极大提高，其磨损特征为冲蚀粒子冲击作用下产生的裂纹、破碎与块状剥落.

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.