摘要
目的 在极端工况下运行的设备常出现乏油现象,容易造成严重的零件磨损,导致设备出现故障。为了提高零件材料表面的摩擦学性能,探索乏油工况下织构表面的减摩润滑方法。方法 设计并制备一种具有固液复合润滑单元的织构表面。利用激光打标机在45#钢表面制备圆形微坑织构,并填充聚酰亚胺(PI)泡沫、蓖麻油和聚四氟乙烯(PTFE)块,制得具有固液复合润滑单元的织构表面。采用球盘式往复摩擦磨损实验,在乏油工况下对比3种表面的摩擦学性能,即具有固液复合润滑单元织构表面、凹坑含油织构表面和凹坑填充PTFE织构表面。利用扫描电镜和激光共聚焦显微镜分析磨损情况,借助高速摄影机观测3种表面的润滑过程,并分析其润滑机理。结果 具有固液复合润滑单元的织构表面具有优良的减摩润滑功效,与凹坑含油织构表面和凹坑填充PTFE织构表面相比,其摩擦因数分别降低了54.5%、41.7%,其磨损量分别降低了83.5%、58.9%。此外,固液复合润滑单元内的PTFE块磨损较轻。通过高速摄影发现,对偶球与固液复合润滑单元在摩擦过程中能够将润滑油和PTFE粉末带到摩擦副表面。结论 具有固液复合润滑单元的织构表面的润滑机理为摩擦带出的润滑油和PTFE粉末具有固液复合润滑的效果。创新点为微挤压供油和弹性接触减摩的结构特点能够提高单元内的润滑油利用率,减小PTFE块的磨损。具有固液复合润滑单元的织构表面的摩擦因数和表面磨损量均较低,有效改善了乏油工况下织构表面的摩擦学性能。
Equipment running under extreme conditions often has a phenomenon of oil starvation,which often causes serious part wear and even equipment failure.In order to improve the tribological properties of the material surface,the work aims to explore the anti-friction lubrication method of the textured surface under the condition of oil starvation.To improve this situation,a textured surface with solid-liquid composite lubrication units was designed and prepared.A circular micro-pit texture was prepared on the surface of 45#steel by laser marking machine and filled with polyimide(PI)foam,castor oil and polytetrafluoroethylene(PTFE)blocks.The ball-disk reciprocating friction and wear test was carried out and the tribological properties of three surfaces were compared under oil starvation conditions,including the textured surface with solid-liquid composite lubrication units,the pit filled oil textured surface,and the pit filled PTFE textured surface.The wear surfaces and cross sections of wear scars were analyzed with scanning electron microscopy and confocal microscopy.High-speed photography was employed to observe the lubrication mechanisms of the three surfaces.The experimental results indicated that the textured surface with solid-liquid composite lubrication units exhibited excellent anti-friction lubrication properties.Compared to the pit filled oil textured surface and the pit filled PTFE textured surface,the textured surface with solid-liquid composite lubrication units showed a reduction in the coefficient of friction by 54.5%and 41.7%,respectively,and the wear amount was reduced by 83.5%and 58.9%,respectively.Additionally,the PTFE blocks within the solid-liquid composite lubrication unit demonstrated lower wear rates.It was found by high-speed photography that lubricating oil and PTFE powder could be brought out to the surface of the friction pair during the friction process between the counterpart ball and the solid-liquid composite lubrication unit.The PTFE blocks within the composite lubrication unit surface were arranged in an assembly manner,allowing axial movement along the recesses.High-speed photography showed two peculiarities.The first one was that there was no direct hard contact between the PTFE block and the counterpart ball and instead,a small displacement occurred when they contacted,avoiding hard impact on the PTFE block by the counterpart ball.This showed that an elastic contact behavior was formed between the PTFE block and the counterpart ball.The other one was that when the PTFE block contacted the counterpart ball,the PTFE block moved down along the recess and squeezed the oil-containing foam in the recess.The lubricating oil stored in the squeezed PI foam overflew from the central hole of the PTFE block to the surface of the PTFE block,and then was brought into the surface of the friction pair through the contact zone of the counterpart ball,providing lubricating oil for the surface the friction pair,thus achieving the effect of liquid lubrication.The above-mentioned oil supply behavior of the oil-containing PI foam under the micro-sezing of the PTFE block was named as micro-squeezing oil supply.In conclusion,the lubrication mechanism of the textured surface with solid-liquid composite lubrication units is that the lubricating oil and PTFE powder brought out by friction have the effect of solid-liquid composite lubrication.The innovation point is micro-extrusion oil supply and elastic contact characteristics,which enhances the utilization of lubricating oil within the unit,reduces PTFE wear,and enables both liquid and solid lubrication on the textured surface.The textured surface with solid-liquid composite lubrication units has lower friction coefficient and surface wear.
作者
汤维冬
于爱兵
郭旭峰
秦拓
叶家往
叶玮豪
TANG Weidong;YU Aibing;GUO Xufeng;QIN Tuo;YE Jiawang;YE Weihao(School of Mechanical Engineering and Mechanics,Ningbo University,Zhejiang Ningbo 315211,China)
出处
《表面技术》
北大核心
2025年第17期58-66,共9页
Surface Technology
基金
国家自然科学基金(51875294)。
关键词
乏油
织构
磨损
固液复合润滑
润滑机理
oil starvation
texture
wear
solid-liquid composite lubrication
lubrication mechanism
作者简介
通信作者:于爱兵。
