ABSTRACT
This chapter focuses on developed micro-mechanical model of stress softening and filler induced hysteresis of elastomer materials, which combines well established concepts of rubber elasticity with a micro-mechanical approach of dynamic filler flocculation in the cyclically strained rubber matrix. The filler induced hysteresis is described by a free energy term, considering the cyclic breakdown and re-aggregation of the residual fraction of more fragile filler clusters with already broken filler-filler bonds. The model assumes that the breakdown of filler clusters during the first deformation of the virgin samples is totally reversible, though the initial virgin state of filler-filler bonds is not recovered. On the other side, the fraction of fragile filler clusters increases with increasing pre-strain, which impacts the filler-induced hysteresis. The obtained microscopic material parameter appear reasonable, providing information on the mean size and distribution width of filler clusters, the tensile strength of virgin as well as damaged filler-filler bonds and the polymer network cross-linking density.
