葫芦形微凹坑对不锈钢表面摩擦学性能的影响

本文中利用皮秒激光系统对不锈钢表面进行织构化处理,通过Fluent有限元软件和UMT-2摩擦磨损试验机分析了非规则对称葫芦形织构表面的摩擦学性能,并与具有规则对称性的圆凹坑织构试样及光滑织构试样进行对比,同时利用S-3400 N扫描电镜观察试样表面的磨痕形貌.结果表明:润滑状态下葫芦形正方向织构试样的摩擦系数要明显低于圆凹坑织构试样及无织构光滑试样,葫芦形反方向织构试样的摩擦系数与圆凹坑织构试样相近.这主要是由于织构形状及润滑液流动方向对织构试样产生流体动压效应的影响较大.因此,在润滑液流动方向上,扩大织构自身形状的收敛区间可以强化织构的流体动压效应,这一结论将为进一步优化织构形状提供有力参考.

The Effect of Gourd-Shaped Surface Texture on Tribological Performance of Stainless Steel

Picosecond laser texturing system is used to fabricate the surfaces in this paper. Fluent and UMT2 are used to analyze the tribological performance of the gourd-shaped surface texture on the stainless steel under lubricated conditions, and the tribological performance of gourd-shaped texture surface was compared with that of the regular circular texture surface and untextured surface. Moreover, the images of wear track after tests were observed by using the S-3400 N scanning electron microscopy. The results show that the gourd-shaped surface texture with positive direction obtained the lowest frictional coefficient among the patterns investigated, and the frictional coefficient of gourd-shaped texture surface with negative direction was comparable to that of the circle texture surface. The main reason was that the shape of surface texture and the lubricant flowing direction had significant influence on the generation of fluid dynamic pressure. It proves that enlarging the converge area of the texture shape along the direction lubricant flowing direction enhanced the fluid hydrodynamic effect, and this result provided a good guideline for shape optimization of surface texture.