关键词: 结合面, 接触刚度, 接触阻尼, 预估, 分形模型

Abstract: A new fractal model for the normal parameters of joint surfaces was established based on fractal contact theory. The model suggests that the values of normal contact parameters such as the contact stiffness and the contact damping can be estimated by obtaining the normal contact load, material properties of rough surfaces and fractal parameters. The varying laws of normal contact parameters were also simulated numerically. The research results indicate that the entire contact area of joint surfaces can be divided into the elastic and the plastic regions. And the small spots are in plastic contact whereas the large spots are in elastic contact. Besides, the relations between normal contact parameters of joint surfaces and fractal parameters are of strong nonlinearity. Moreover, the effects of normal load on contact stiffness are obvious. As the normal load is increased there is also a distinct increase in the behavior of normal contact stiffness. However, the normal load has less effect on the normal damping of joint surfaces. In addition, the extreme points in the varying curves might provide the reference for the optimization design of these contact parameters.

Key words: joint surfaces, contact stiffness, contact damping, estimation, fractal model