Fabrication and Tribological Properties of High Temperature Self-Lubrication Composites Prepared by Gas-Pressure Infiltration Technique

Abstract

Powder metallurgy derived microporous Al2O3/FeCrWMoV metal ceramic preforms were infiltrated with 60Pb40Sn based solid lubricants to create almost fully dense self-lubrication composites. By means of scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDS), it was found that 60Pb40Sn-based solid lubricants are well dispersed and embedded in the Al2O3/FeCrWMoV matrix. The friction and wear behaviors of the composites sliding against ZrO2 ceramic from ambient to 800 °C were investigated using a pin-on-disk wear tester.The results showed that the composites exhibited self-lubricating properties at elevated temperatures up to 700 °C. The friction coefficients of less than 0.27 at 600 °C and wear rates of 6×10−6 mm3/N m are obtained when rubbing against ZrO2 ceramic under a normal load of 50 N and a sliding speed of 0.139m/s for 2 hours. The occurrences of lower friction coefficient and plateau in wear rate have been related to the formation of a film of lubricant almost covered entirely the substrate beneath.