颗粒脱黏对异质摩擦界面点接触弹流润滑的影响

建立了异质摩擦界面点接触弹流润滑模型,利用MATLAB对其进行数值仿真,研究了颗粒脱黏对接触区域油膜厚度和压力分布的影响,并分析了异质材料内部的最大剪应力分布情况。结果表明,不同形式的颗粒脱黏均会增加颗粒分布区域的油膜厚度,其中颗粒上方脱黏的作用最为明显;随着颗粒埋布深度的增加,其脱黏对于膜厚的影响逐渐减小,高弹性模量颗粒脱黏对油膜厚度变化的影响小于低弹性模量颗粒脱黏;颗粒发生脱黏后,油膜压力会在油液移出颗粒分布区域时产生激增,严重影响点接触弹流润滑性能;颗粒脱黏会在颗粒靠近脱黏区域的两侧形成很大的剪应力,从而导致异质材料产生裂纹甚至断裂等进一步失效。

Effect of particle debonding on point contact elastohydrodynamic lubrication of heterogeneous friction interface

The point contact elastohydrodynamic lubrication model of heterogeneous friction interface was established, which was numerically simulated by MATLAB. The effect of particle debonding on the oil film thickness and pressure distribution in the contact area was studied, and the maximum shear stress distribution inside the heterogeneous material was analyzed. The results show that different forms of particle debonding can increase the oil film thickness in the particle distribution region, and the increase of oil film thickness is most obvious with the debonding above the particles. The effect of particle debonding on the film thickness decreases with the increase of the particle depth, and the high elastic modulus particle debonding has a less sighificant effect than the low elastic modulus particle debonding. After particle debonding, oil film pressure may increase sharply and seriously affect point contact elastohydrodynamic lubrication when the oil leaves the particle distribution region. Debonding of particles can cause large shear stress on both sides of the particle near the debonding region, resulting in further failure of cracks or even fracture of the heterogeneous material.