CuNiIn微动磨损涂层失效机理研究

Failure Mechanism of Cu Ni In Fretting Wear Coatings

目的系统研究CuNiIn和CuInO_2的晶体结构、体模量、剪切模量、杨氏模量、泊松系数、韧性、热膨胀系数、残余应力等物理参量,阐明CuNiIn涂层中生成的其他复合化合物—CuInO_2对CuNiIn机械性能的影响作用机制。方法采用基于密度泛函理论的第一原理,弹性常数采用应力-应变方案,体模量、剪切模量、杨氏模量采用Voigt-Reuss-Hill方法计算。结果CuNiIn和CuInO_2均为机械稳定结构,CuNiIn和CuInO_2的体模量、剪切模量、杨氏模量、泊松系数分别为118.2GPa,13.7GPa,39.6GPa,0.44和119.0GPa,36.8GPa,100.1GPa,0.36。化合物CuInO_2的机械模量较CuNiIn高,韧性较差,热膨胀系数较低,涂层的残余应力较高。结论喷涂工艺不适,或CuNiIn涂层服役过程中生成的CuInO_2对微动磨损CuNiIn涂层服役性能有不利影响。

Objective In this investigation, the crystal structure, bulk modulus, shear modulus, Young modulus, Poisson ratio, toughness, thermal expansion coefficients and residual stress of CuNiIn and CuInO2 were inspected systematically, and the influencing mechanism of the material of Cu In O2 in CuNiIn coatings on the mechanism performance of CuNiIn was elucidated. Methods Elastic constants were obtained with stress-strain method using the first principles density function theory. Bulk, shear and Young modulus were obtained using Voigt-Reuss-Hill methods. Results The study indicated that CuNiIn and CuInO2 were mechanically stable structures. The bulk modulus, shear modulus, Young modulus and poisson ratio for CuNiIn and CuInO2 were 118.2 GPa, 13.7 GPa, 39.6 GPa, 0.44, and 119.0 GPa, 36.8 GPa, 100.1 GPa, 0.36, respectively. The mechanical modulus of CuInO2 was higher than that of Cu Ni In. The toughness of CuInO2 was poorer, the thermal expansion coeffieent was lower and the inner residual stress of CuInO2 was higher than those of CuNiIn. Conclusion Improper spray process parameters or the CuInO2 produced during the service process had negative effects on the service performance of CuNiIN fretting wear coatings.