A numerical approach towards understanding the mechanism of fatigue wear in tread vulcanizates during rolling of tires

Analysis of surface fracture and progress of fatigue wear on the surface of tire tread under road asperity loading is the main objective of this study. Starting with an idealized smooth surface of having precursor flaws, a simple mechanism for formation of wear debris and development of surface patterns is proposed. In this mechanism, step-wise propagation of these micro-flaws under periodic loading by asperities of the road is simulated using Moving Template Finite Element Analysis (MTFEA) in linear geometry and further analyzed using ABAQUS software in non-linear geometry.; It is attempted to extend this analysis to heterogeneous rubber compounds where dispersed particles may affect propagation of surface cracks. Mechanical characterization of all existing phases i.e. rubber matrix, filler reinforcing units, and dispersed rubber particles (minor phase in blends) under similar conditions as asperity loading is performed by experimental/numerical methods prior to any stress analysis of such systems. Also, some features of carbon black reinforcement such as stress/strain amplifications in the rubber phase and distribution of stress/strain in constituents of the compound are predicted by combining FEA with experimental observations.; Applying mechanical properties of all phases in local FEA models, interactions between ongoing crack tips and dispersed particles are analyzed. Some mechanical mechanisms by which filler reinforcing units and dispersed rubber particles retard propagation of cracks and possibly improving wear resistance are hypothesized.