Modeling Friction and Abrasion in Rubber

The exact mechanisms that are present during frictional sliding and abrasion of an elastomer over a hard surface are still not fully understood. Practical investigations have been undertaken in parallel with finite element analysis to investigate how the frictional force is developed as well as how this relates to abrasion of the elastomer. It is widely accepted that the two principal factors in rubber friction result from the adhesion and hysteresis behaviour of the elastomer. This work has shown that an additional (third) geometric factor, contributes significantly to the frictional force. It can under certain conditions, increase the frictional force above that expected from a consideration of the interfacial coefficient of friction alone. This geometric term is thought likely to make a significant contribution to friction experienced in applications such as the sliding of tyres over a road surface. The abrasion process has also been modelled using a calculated stored energy release rate for a specific typical asperity and this has been used to compare both measured and calculated abrasion rates. The correlation is excellent for a wide range of conditions and different materials and this analysis helps explain why some materials are more abrasion resistant than others.