固定接触界面法向静弹性刚度

Normal static elastic stiffness of fixed contact interface

基于Hertz接触理论推导了两个微凸体之间互相作用的法向接触静弹性刚度。根据修正后的一个微接触点的平截面积尺寸分布,给出了界面的总法向接触静弹性条件刚度、总条件载荷的解析解。将法向静弹性刚度的解析解嵌入到有限元软件中,获得整机的理论模态。通过实验对解析解进行了定量验证。以机床结合部为研究对象,在理论振型与实验振型一致的条件下,模型的相对误差在-17.8%~17.3%之间。

The solution for contact normal static elastic stiffness of two interacting asperities is derived by means of Hertz contact theory.The analytical expressions for the joint interface total normal contact static elastic stiffness with a certain condition and total load with a given one are deduced according to the modified size distribution of a microcontact truncated area.The theoretical mode in whole machine tools could be obtained when the analytical solution for normal static elastic stiffness is inserted into finite element software.The analytical solutions are quantitatively validated by experiments.A joint interface in machine tools is selected as an example,in view of the encouraging coincidence of theoretical vibration modes with experimental ones,the relative discrepancies in the model are between-17.8 % ~17.3 %.