Investigations on Contact Pressures and Durability of Metal-Polymer Dry Sliding Bearings with Miniature, Small and Large Diameters

Shaft diameters of sliding bearings, including metal-polymer, can be much differentiated. The carrier capacity and durability of metal-polymer (MP) sliding bearings of miniature, small, medium and large diameters were investigated according to author's calculation method. Such main types of thermoplastic polymeric materials are used for bushings: PA polyamide and its composites, PTFE polytetrafluoroethylene composites, PEEK polyetheretherketone and its composites, PET polyethylene terephtalate and its composites. The main thesis of author's calculation methods for studying the contact strength of polymer bushing, wear and durability of MP bearings, the method of model triboexperimental studies of metal-polymer pairs under dry sliding friction are presented. The research results are presented in the form of wear resistance diagrams and the wear resistance characteristics of polymer materials established by them. Quantitative and qualitative results of the MP bearings shaft diameters influence on the maximum contact pressures and durability are presented. It was established that for the range of shaft diameters 2 ... 20 mm there is a nonlinear dependence of the decrease in maximum contact pressures. For larger diameters, this dependence will be close to linear. Similar patterns in the durability of bearings with different polymer bushing materials are observed. Their durability depends significantly on the type of polymer bushing.