含颗粒缺陷涂层材料线接触力学性能数值分析

目的建立线载荷作用下含颗粒缺陷涂层材料的数值分析模型,探究颗粒缺陷对涂层材料接触力学性能的影响,以期为工程实际中机械传动部件表面的涂层工艺优化设计提供理论指导。方法利用半解析法,构建考虑颗粒缺陷的含涂层非均质材料线接触模型,所得计算结果与有限元法结果吻合良好。基于该模型,研究了摩擦系数、颗粒缺陷的位置及分布对含颗粒缺陷涂层材料最大von Mises应力及其深度位置的影响。结果随着摩擦系数的增大,最大von Mises应力值逐渐增大,其深度位置从涂层内部阶跃至近表面。随着颗粒缺陷中心x坐标从左到右变化,最大von Mises应力值先增大后减小,其深度位置位于涂层与基体界面附近或颗粒缺陷近表面端的上端。随着颗粒缺陷与涂层表面距离的增大,最大von Mises应力值先增大,后减小,并逐渐趋于稳定,其深度位置先逐渐远离涂层表面,随后稳定在涂层内部或涂层与基体界面区域。分布颗粒缺陷对最大von Mises应力的影响较为复杂,其深度则位于涂层与基体的界面或颗粒缺陷与基体的界面附近。结论摩擦系数与颗粒缺陷的位置及分布对涂层材料线接触力学性能均能产生较大影响。

Numerical Analysis on Mechanical Performance of Coated Materials Containing Particle Defects under Line Contact Load

The work aims to establish a numerical analysis model of coated materials with particle defects under the linear load, so as to explore the effects of particle defects on the contact mechanical performances of coated materials, and provide theoretical guidance for the optimization design of coating technology for mechanical transmission parts in engineering. Semi-analytical method (SAM) was employed to construct a linear contact model for heterogeneous coated materials containing particle defects and the calculated results were in good agreement with those obtained by the finite element method. Based on the model, the effects of friction coefficients and the locations and distributions of particle defects on the value and depth of maximum von Mises stress in coated materials containing particle defects were studied. The maximum von Mises stress went up, and the depth positions exhibited step changes from near matrix-coating interface to the coating surface, with the increase of the friction coefficient. When the x-coordinate of the particle defect center changed from left to right, the maximum von Mises stress increased and then decreased, the corresponding depth positions were located near the matrix-coating interface or the upper surface of the particle defect. With the increasing distance between the particle defect and the coating surface, the maximum von Mises stress increased, then decreased, and became stable, and the depth position went away from the coating surface and then stayed in the coating area or the matrix-coating interface area. The effects of the randomly distributed particle defects on the maximum von Mises stress were complicated, and the depth positions were located near the matrix-coating interface or the interface between the matrix and particle defects. Friction coefficient and locations and distributions of particle defects can greatly affect the contact mechanical performances of the coated materials containing particle defects under a linear load.