激光重熔对Al_2O_3-40%TiO_2等离子喷涂层耐冲蚀性能的影响

Effect of laser remelting on erosion resistance of plasma sprayed Al_2O_3-40% TiO_2 coating

利用等离子喷涂方法制备Al_2O_3-40%TiO_2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Al_2O_3-40%TiO_2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Al_2O_3-40%TiO_2等离子喷涂层的层状结构,使得等离子喷涂层中γ-Al_2O_3转变为α-Al_2O_3,形成了α-Al_2O_3+TiAl_2O_5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.

The Al_2O_3-40% TiO_2 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 Al_2O_3-40% TiO_2coating was studied. The results show that the layered structure of plasma sprayed Al_2O_3-40% TiO_2coating can be changed by the laser remelting. The γ-Al_2O_3 phase transforms into α-Al_2O_3,and the laser remelted coating exhibits a stable structure which consists ofα-Al_2O_3 and TiA l2O5. A compact,uniform,highly hard and good metallurgical bonded Al_2O_3-40% TiO_2coating 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.