Dynamic and kinematic effects in the friction and wear of rubber

Research is presented which focuses on the micro-mechanical processes that dominate the friction and wear of rubber. New test concepts and equipment were developed to study the dynamic and kinematic effects involved in these processes. Several new analytical tools were presented to explain the observed results in quantifiable terms.; Experiments conducted on filled NR confirmed that a transition in wear behavior does not occur across a wide range of power inputs. Examination of the debris distributions across the contact revealed that an agglomeration process of intrinsic particles occurs, the extent of which is purely a function of distance from the contact's leading edge. This revelation is used to explain the commonly reported bimodal size distribution of debris generated during rubber wear and to expose the mechanical process that generates intrinsic debris as the primary cause of wear.; The effect of contact length (i.e. extent of agglomeration) on corresponding friction and wear levels was studied.; The effects of dynamically changing slip orientation on the properties of a coated abrasive and the friction and wear of a filled SBR were studied.; The process of removal of intrinsic debris from a rubber surface was described in terms of a micro-mechanical fatigue fracture process that occurs at varying rates that are dependent on the frictional work acting on the average intrinsic nodule. The model was successfully tested against previously published data and new data and was shown to account for pressure and abrasive effects with one set of two constants.; The potential effects of pattern morphologies on rubber friction and wear were examined as well.; The wear patterns showed a clear tendency to roll up as opposed to peeling back.; The intrinsic wear model was then applied to a description of pattern wear by assuming that the rate of intrinsic abrasion across a pattern is simply a function of the local pressure distribution which varies from the front to the back face of the pattern. For both blade and abrasive wear, the application of the intrinsic wear model was shown to be capable of predicting many of the recognized behaviors of rubber pattern wear. (Abstract shortened by UMI.)...