Fatigue failure of 45# steel in dry sliding against Kevlar/PTFE hybrid composite under elevated load:

Frictional failure is inevitable for friction pairs. A common sense about the frictional failure of steel-polymer composite friction pair is that the polymer composites are the primary failure part rather than the steel counterpart. However, an opposite case was newly found in the case of fabric self-lubricating liner (Kevlar/PTFE hybrid composite) spherical plain-bearing under elevated load: the steel counterbody suffered a fatigue failure before the fabric composite fails, which resulted in the final failure of the bearing. This paper investigated such fatigue failure of surface chrome plated 45# steel by systematically studying the wear characteristics of 45# steel and fabric composite, the stress distribution of the 45# steel and fatigue features within cross section of the 45# steel. Results showed that wear characteristics of both fabric composite and 45# steel exhibited regional characters. Failure mechanism of the 45# steel was found to be fatigue failure (mainly fatigue pitting), which was reveal...