氧化铝增强镍基合金涂层的组织与耐冲蚀磨损性能研究

Study on microstructure and erosion resistance of Al_2O_3 reinforced Ni-base alloy coating

采用等离子喷涂(APS)方法制备了用Ni包Al作为过渡层材料,球磨法混合G112和不同含量的Al2O3粉末作为面层材料的金属-陶瓷涂层。用扫描电镜(SEM)、X射线衍射仪(XRD)对涂层显微组织和相结构进行了分析,用图像分析系统测试了涂层孔隙率,并对涂层在冲蚀磨损试验机上以30°、60°和90°冲蚀角进行了冲蚀磨损试验。结果表明,随Al2O3含量增加涂层的耐冲蚀磨损性能先上升后下降,18%wt.AlO时耐冲蚀性能最好,其升降规律与冲蚀角度无关而与孔隙率密切相关。

Al_2O_3 particle reinforced Ni base alloy composite coating on Q235 steel substrate was prepared by plasma spraying.The Ni-clad Al was first sprayed as the transition layer and then, ball-milling mixed G112 with different contents of Al_2O_3 was sprayed as the surface coatings. The structure of the coatings was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), and the porosity of the coatings was measured by an image analyser.Tests on erosion resistance of the coatings were carried out on a conventional erosion tester with the injection angles of 30°,60°and 90°.The results show that the erosion resistance of the coatings increases with increasing Al_2O_ 3 content, reaches the maximum at 18wt% Al_2O_3 and decreases with further increase of Al_2O_3 content. The variation of erosion resistance of the coatings with Al_2O_3 content are independent of the injection angle, but are closely related to the porosity of the coatings, while the weight loss of erosion decreases with the increase of injection angle.