纳米凹土纤维对碳钢摩擦副的润滑及原位修复效应

The lubricating and in situ reconditioning effects of the nanoscale attapulgite fibers on carbon steel tribopairs

以纳米凹土纤维为原料采用机械球磨法制备了一种摩擦改性剂,利用往复摩擦磨损试验机评价了其对碳钢摩擦副的润滑及原位修复作用,借助扫描电子显微镜(SEM)、能量色散谱仪(EDS)及纳米压痕仪(nano-indenter)对自修复层进行了表征,探讨了其减摩抗磨及自修复机理。结果表明,纳米凹土纤维具有优异的减摩抗磨性能且与载荷和速度的匹配有关;在50 N、1.0 m/s时具有较低的摩擦系数及磨损率,分别较基础油降低约58%和81%。凹土纤维参与了摩擦表面复杂的理化作用,诱发形成了较为均匀连续的"多孔"修复层,厚约1.52μm;表面较为光滑平整,主要由Fe、C、O、Si及微量的Mg、Al元素构成,具有较高的纳米力学性能,有效地降低了摩擦磨损。

A friction geometry modifier was prepared out of nanoscale attapulgite fibers using mechanical ball-milling method.The lubricating and in situ reconditioning effects of the as-prepared modifier on carbon steel tri-bopairs were evaluated by employing a reciprocating friction and wear tester.The mechanisms for friction and wear reducing and reconditioning effects were discussed based on the characterization of the self-reconditioning layer with scanning electron microscope （SEM）,energy dispersive spectroscope （EDS）and nano-indenter.Re-sults show that the nanoscale attapulgite fiber has excellent friction and wear reducing performance associated with the match of the applied load and sliding velocity.Under the condition of 50 N and 1.0 m/s,the corre-sponding friction coefficient and mass wear rate reach the lowest value,and decrease by 58% and 81%,respec-tively,compared to those of the base oil.An induced uniform and continuous multi-apertured self-reconditioning layer has formed on the friction surface with a thickness about 1.52 μm due to the complex physicochemical in-teractions between the fibers and contact surface.The layer shows smooth and possesses nano-mechanical prop-erties,which was responsible for the significant decrease in friction and wear,mainly with Fe,C,O,Si and small content of Mg and Al.