Verbesserung des Reibungskoeffizienten von partikelgefülltem Epoxidharz durch Flüssigschmierstoffe

Epoxy resin based sliding materials containing nanoparticles, aramide particles and graphite offer excellent wear resistance but a relatively high coefficient of friction (= 0,4). In order to reduce the coefficient of friction to an applicable value the influence of liquid lubricants (PFPE, Perfluorpolyether) as internal lubrication is investigated. The mechanical properties as well as the tribological behavior under continuous and reciprocating sliding are determined. The influence of PFPE (0,5 - 4,0 Vol. %) on the material's stiffness is low. However,the bending strength, strain to break and impact energy is reduced significantly. A remarkable decrease of the coefficient of friction by PFPE leads on the other hand to a small increase of the specific wear rate. The lowest coefficient of friction (0,24) at a wear rate of 1,12 × 10^-6 mm³/Nm is measured for a composition containing 2,0 Vol. % PFPE. A reduction of the coefficient of friction combined with a higher wear rate is caused by a thick, patchy transfer film on the counterpart (mainly due to graphite) and a partial oil film. No significant changes of the wear properties under reciprocating load could be measured.