基于微凸体接触的粗糙表面摩擦模型以材料硬度、弹性模量、剪切模量、泊松比、表面粗糙度、微凸体高度分布概率函数和正压力等为输入参数,模拟摩擦副往复运动摩擦行为,可获得摩擦力-位移(F-δ)曲线、接触界面微凸体滑移情况.利用该模型模拟了心盘磨耗盘摩擦行为,结果表明:往复行程为2μm时,F-δ曲线为椭圆形,接触微凸体为部分滑移,往复行程大于2μm时,F-δ曲线由椭圆形逐渐变为矩形,接触微凸体由部分滑移逐渐变为完全滑移;材料表面粗糙度对摩擦系数及摩擦力的影响较小,但对接触表面的微凸体滑移特性有明显影响,粗糙度越大,引起接触微凸体完全滑移所需的位移越大,相同的位移下,发生滑移的微凸体越少.
A friction model of rough surfaces based on asperities contact can be used to simulate the reciprocating motion of friction pairs with the input parameters of hardness, young' s modulus, shear modulus, poisson' s ratio, surface roughness, probability density function of asperity height, normal load, and many others. And the friction force -reciprocating distance (F-δ) curves, sliding conditions of asperities can be obtained through thefriction model. The friction behavior of center disc wear plate was studied with the model. The results indicate that the shape of F - δ curves under the reciprocating distances of 2 μm was elliptical. Some of asperities in the contact zone slipped. The F - δ curves change to quasiparallelogram shape under the reciprocating distances of 6 μm and 10 μm. Meantime,all asperities in the contact zone slipped. The surface roughness had little effect on the friction coefficient and friction force. It significantly influenced the slipping properties of asperities. With increasing the surface roughness, the reciprocating distances inducing all asperities slipping increased. And the number of slipping asperities decreased under the same reciprocating distance.