表面织构参数对液压马达滑靴副的摩擦学性能影响研究

Effect of Texture Parameters on Tribological Performance of Slipper Surface in Hydraulic Motor

目的通过表面织构改善液压马达连杆滑靴副的摩擦学性能。方法首先,基于Reynolds方程研究表面织构参数(直径d、面密度s_p、深度hp)对滑靴副的无量纲压力(P_(av))的影响规律。其次,设计正交试验研究表面织构参数对摩擦系数的影响,分析表面织构的润滑机理。结果 P_(av)随着d的增加而增大;随着s_p的增大,先增加后缓慢减小,当s_p=10%时,Pav达到最大值。此外,随着_hp的增大,P_(av)先增加后快速减小,在h_p=2μm时达到最大值。摩擦实验结果表明,合适的织构参数能有效降低摩擦系数,7#织构表面(d=700μm,s_p=10%,h_p=5μm)的摩擦系数最小为0.034,比无织构表面的降低66%。正交极差分析表明,各因素对摩擦系数影响的主次顺序为:直径>面密度>深度。摩擦系数随着直径的增大而减小,随着面密度的增大而增大,随着深度的增大而减小。结论经过优选的表面织构参数有利于形成动压润滑,从而降低摩擦系数和磨损。

The work aims to improve the tribological performance of the hydraulic motor slipper pair by surface texture.Firstly, the effect of surface texture parameters(diameter d, surface density sp, depth hp) on the dimensionless bearing capacity(Pav) of textured connecting rod surface was investigated based on Reynolds equation. Secondly, the friction coefficients of surface texture with different parameters were studied by orthogonal experiments, and the corresponding lubrication mechanism was analyzed. Pav increased linearly with the increase of d, while Pav first increased and then decreased with the increase of sp,and the maximum Pav was obtained at sp of 10%. As the hp increased, Pav first increased and then decreased and reached the maximum at hp of 2 μm. The friction coefficient of the textured surface with suitable parameters was effectively reduced. The 7#surface(d=700 μm, sp=10%, hp=5 μm) had a minimum friction coefficient of 0.034, which was 66% lower than that of the non-textured surface. Range analysis showed that the influence order of factors on the friction coefficient was: diameter>area density>depth. The friction coefficient decreased with increase of diameter and depth, but increased with the increase of area density. The surface texture parameters through selection are beneficial to formation of dynamic pressure lubrication to reduce friction coefficient.