【摘要】 基于分形接触理论,建立了结合面法向接触参数的分形预估模型,通过粗糙表面材料性能参数、法向载荷及粗糙表面的分形参数来预估法向接触刚度和接触阻尼,并对其变化规律进行数值仿真.结果表明:结合面之间的接触处于弹性变形和与塑性变形共存的状态,且小接触点面积的微凸体发生塑性变形,而大接触点面积的微凸体发生弹性变形;法向接触参数与分形参数之间具有较强的非线性关系;同时,法向接触刚度随法向载荷的增大而逐渐增加,但法向载荷对结合面的法向阻尼特性影响较小;仿真结果中极值点的存在,为结合面接触参数的优化设计提供了依据.更多还原

【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.更多还原