基于勒让德-扫描法的机械结合部法向接触刚度区间分析

Interval analysis for normal contact stiffness of mechanical joint surface based on the Legendre-scanning method

由于机械结合部实际接触时存在诸多不确定因素,利用传统接触刚度模型对机械结合部进行分析时,难以确定其法向接触刚度的合理区间。为此,将微凸体曲率半径、分布密度和微凸体高度方差视为不确定性参数,基于KE弹塑性接触刚度模型和勒让德-扫描法,建立结合部法向接触刚度区间模型并进行求解。通过与接触刚度试验数据及传统模型求解结果的对比,验证了该模型的有效性和准确性。基于该模型对结合部法向接触刚度进行分析,结果表明:勒让德-扫描法具有较高的求解精度,粗糙表面形貌参数不确定性对于结合部法向接触刚度有着明显影响,且随着无量纲接触距离的减小,影响程度逐渐增加,其中微凸体高度方差的不确定性对粗糙表面法向接触刚度影响程度最大。机械结合部法向接触刚度区间模型的建立与分析,可为结合部的研究提供参考。

An interval model was established to analyze the normal contact stiffness of a mechanical joint.The model considers uncertain parameters such as asperity radius of curvature,distribution density,and asperity height variance.To address the limitations of traditional contact stiffness models in determining the reasonable range of normal contact stiffness,the KE elastic-plastic contact stiffness model and Legendre polynomials were utilized.The model was validated by comparing it with contact stiffness test data and traditional model solution results.The feasibility and accuracy of the Legendre-scanning method were proved by the results.Results show that the rough surface topography parameters have a significant impact on normal contact stiffness,with the uncertainty of asperity height variance having the greatest influence.As the dimensionless contact distance decreases,the degree of influence increases.The establishment and analysis of the interval model for normal contact stiffness in mechanical joints can serve as a reference for further research on joint.