分形表面接触变形对部分膜润滑的影响

Influence of Contact Deformation of the Fractal Surfaces on the Partial Film Lubrication

在M-B分形接触模型的基础上,利用引入接触因子的平均流动模型,分别计算在考虑和不考虑分形表面接触峰变形情况下的流量因子和接触因子,研究分形表面接触变形对润滑状态的影响.结果表明:接触变形使得各因子减小,其中对剪切流量因子的影响最大,对压力流量因子和接触因子的影响相对较小,尺度系数越大,接触变形对剪切流量因子最大值的影响越大,剪切流量因子变化越缓慢,弹塑性变形的转化范围越宽;对于一定的名义膜厚,随着分形维数增加,接触弹塑性的转变会使变形对各因子的影响先增后减;对于相同的尺度系数,接触变形对流量因子的影响在相同的分形维数范围内达到最大值.

Fractal surface was introduced into the average flow model and effect of elastic-plastic contact deformation of fractal surfaces on the flow factors and contact factor were analyzed based on the M-B fractal contact model for partial film lubrication. The factors were calculated with and without consideration of contact deformation. Contact deformation decreased the factors and could not be neglected for tact deformation on the shear flow factor was the largest among the partial film lubrication. The effect of the confactors and the shear flow factor was effected more greatly and changed slower for greater scale coefficient. For the same nominal film thickness, the effect on all the factors increased firstly and then decreased with the increasing fractal dimension as a result of transition from elastic to plastic deformation. For the same scale coefficient, the effect on the factors became greatest almost in the same range of fractal dimension.