Surface analysis of iron-based self-lubricating composite under oil lubrication

Abstract

To improve tribological performances of the tribopairs of hydraulic pump, a kind of new iron-based self-lubricating composite was made and tested on an end-face tribometers under oil lubrication conditions in this work. The results show that the worn surface has shallow furrows and slight wear at different speeds, and the wear type mainly attributes to oxidation wear. When the speed reaches 0.8 m/s, the wear volume of the lower friction pair reaches the maximum 0.289 mm³. This can be due to the fact that the wear debris destroys the lubricating film since the content of mechanical impurities in the lubricant reaches the maximum at this speed. The chemical components characterization of the lubricant shows that the functional groups in lubricating oil after sliding have not changed significantly, but the concentration of the chemicals decreases. This confirms that the lubricating oil with lubrication additives can form tribofilm through chemical reaction during boundary lubrication sliding process to achieve superior antifriction and antiwear effect. While in 1.0 m/s speed, the thicker adsorbed oil film was formed on the sliding interfaces of the iron-based self-lubricating composite, playing an excellent lubrication role.