Study on sensitivity analysis of tooth surface roughness parameters and contact stress

The reasonable selection of three-dimensional roughness parameters can evaluate the service performance of the machined surface, and its excessively high dimension greatly increases the difficulty of selection. In order to reveal the correlation law between the 3D roughness parameters and the tooth surface contact performance parameters, the correlation analysis theory is used to explore the correlation, and the nonlinear mapping model is constructed by using the BP neural network, the genetic algorithm optimization and Morris and Sobol′ two global sensitivity. The qualitative analysis method conducts the qualitative and quantitative analysis of each parameter, selects the three-dimensional roughness parameters that have the greatest impact on the contact performance of the tooth surface, and determines the primary and secondary relationship, solves the problem of parameter redundancy, and provides the theoretical basis for the anti-fatigue design and manufacturing of the tooth surface. The results show that the overall influence of the maximum shear stress on the gear tooth contact and the maximum surface pressure are arranged in the following order: the arithmetic average height ( S a ) and the peak volume ( V mp ), in which S a has a strong correlation. 对三维粗糙度参数的合理选用可以评估加工面的各项服役性能, 而其过高的维度极大增加了选用的难度。为揭示三维粗糙度参数与齿面接触性能参数的关联规律, 借助统计学相关分析理论探究其相关性, 依据遗传算法优化的BP神经网络(GA-BP)构建预测模型, 利用Morris和Sobol′全局敏感性分析方法对各参数进行定性、定量分析, 筛选出对齿面接触性能影响程度最大的三维粗糙度参数, 并确定其主次关系, 解决了参数冗余问题, 为齿面抗疲劳设计制造提供理论基础。研究结果表明, 对轮齿接触最大剪应力与表面最大压力综合影响大小排列均为: 算数平均高度( S a )、峰部的实体体积( V mp ), 其中 S a 达到了强相关程度。