In this article, a test methodology of model scale is used to visualize the processes taking place during operation and subsequent breakdown in the boundary layer of journal bearing materials. The investigated materials are alloys of aluminium (Al99.6, AlSn20Cu, AlSn40) and tin (SnSb7.5Cu3.5). The utilized test configuration is based on a ring-on-disc system. The employed seizure test procedure was designed in previous studies. The tribometric results clearly show differences in the tribological behaviour between the materials. A series of tests are carried out to explain the observed differences. The frictional surfaces and microsections are observed using microscopy and microindentation. Pure aluminium is characterized both by a potentially low coefficient of friction and an unforgiving overload behaviour. This is due to the fact that components based on pure aluminium tend to lose system stability spontaneously. As more of the soft-phase Sn is added to the matrix, the emergency running properties improve. The system behaves less erratically and the overload behaviour improves. However, the mechanical strength and the wear resistance drop. Tribological functional models summarize the results of tribometrics and damage analysis. These models are the key to further optimization of the materials.
Tribological behaviour and transfer layer development of self-lubricating polymer composite bearing materials under long duration dry sliding against stainless steel
