论文部分内容阅读
采用等离子喷涂技术在CuCo_2Be合金表面制备Cr_3C_2-NiCr涂层,通过正交试验确定了CuCo_2Be合金表面等离子喷涂的最优工艺,并对在最佳工艺参数下喷涂的试样,选择在500℃进行高温热震试验,对热震过程中喷涂试样的失效过程进行了跟踪和失效机理研究。研究表明,涂层组织呈现明显的层状,Cr_3C_2-NiCr化合物为角状,涂层与界面的结合以机械结合为主,涂层含有一定量的非晶相。高温热震失效后的涂层中存在铜、镍的氧化物,高温失效主要源自涂层与基体的热应力与氧化过程。
The Cr3C2-NiCr coating was prepared on the surface of CuCo2Be alloy by plasma spray technique. The optimum process of plasma spray coating on the surface of CuCo2Be alloy was confirmed by orthogonal test. The samples sprayed at optimum process parameters were selected to be high temperature Thermal shock tests were carried out to investigate the failure mechanism of sprayed samples during thermal shock. The results show that the microstructure of the coating is obviously lamellar, the Cr_3C_2-NiCr compound is horn-shaped, and the combination of the coating and the interface is mainly mechanical bonding. The coating contains a certain amount of amorphous phase. Copper and nickel oxides are present in the coating after high temperature thermal shock failure. The high temperature failure mainly comes from the thermal stress and oxidation process of the coating and the matrix.