Effect Of Lubricants And Sliding Conditions On The Tribo-performance Of SiO2/epoxy Composites
Free (open access)
199 - 209
J. T. Shen, M. Top, F. Van Rijn, Y. T. Pei, J. Th. M. De Hosson
The influence of solid lubricants, normal load, sliding speed and water environment on the tribo-performance of solid lubricant-containing SiO2-epoxy composites is investigated. 10 to 15 wt% PTFE concentration yields a low coefficient of friction (CoF) and low wear rate under 60 N load. With increasing PTFE concentration in the composites, the load capacity decreases. Graphite exhibits worse friction and wear performance than PTFE under dry sliding condition, i.e. the CoF increases with a decreasing load in ball-on-disc. A higher concentration of PTFE-containing tribolayer on the worn composite surface is found under a higher load. The CoF and ball wear rate increase with increasing sliding speed under dry sliding, which is accompanied with an increase of the surface temperature of the composite. A high relative humidity is advantageous for a low friction due to adsorbed water molecules that lubricate the sliding couple. Water lubrication leads to a lower wear rate of the PTFE and graphite filled composites, whereas it gives rise to a higher wear rate of the Al2O3 ball due to the lack of protection of the transfer films.
PTFE, graphite, friction, load, speed, water