PDMS表面织构润滑特性的研究

Lubrication Properties of Surface Texture on PDMS

利用光刻-复模技术在PDMS表面制作凹坑阵列型表面织构,并采用球-盘式摩擦试验机对具有不同尺寸凹坑阵列的试样进行摩擦试验,研究了软质材料表面织构在混合至流体动压润滑区域的润滑特性.结果表明:对于PDMS材料,凹坑直径是影响摩擦特性的主要因素之一.与无织构试样相比,在低速条件下(0.005m/s)的混合润滑区域较小直径(d=50μm)的织构能够减小摩擦,而较大直径(d=200μm)的织构表现出增大摩擦的效果.在试验范围内凹坑的面积率越大,表面织构的作用越显著.

Surface texture with different parameters was fabricated by the Lithography Replica Molding technique on the soft material PDMS.The effects of surface texture on lubrication properties from mixed to hydrodynamic lubrication regimes were investigated by using a ball-on-disk tribometer.For PDMS,it was found that the diameter of dimples was one of the major factors which influence friction properties obviously.Compared with untextured sample,the pattern with small dimples（with a diameter of 50 μm）resulted a reduction of friction under mixed lubrication and at a low sliding velocity（0.005 m/s）,while the pattern with large dimples（with diameter of 200μm）appeared to increase friction.Textures with high dimple area ratio（from 2.6% to 22.9%）have significances on tribological performance under experimental conditions.