Induced anisotropy by Mullins effect in filled elastomers subjected to stretching with various geometries

摘要: Abstract Anisotropy induced by stress-softening phenomena (Mullins effect) in filled elastomers has been intensively investigated using various stretching modes for pre-stretching. A sequence of two tensile experiments was conducted the evaluation anisotropy: firstly virgin specimens were pre-stretched several modes, i.e., uniaxial, planar, unequal-biaxial and equibiaxial extensions, with degrees strain; secondly, rectangular subsamples, which cut out from relaxed at angles relative to axis larger pre-strain (x-axis), uniaxially stretched. The dependence energy dissipation on direction examined basis comparison uniaxial loading curves subsamples samples. damage x-direction is governed only maximum stretch corresponding direction, it independent degree other (y-direction). damages directions unparalleled are influenced pre-strains both x- y-directions, they well expressed as a sum quadratic effect x-direction, linear that y-direction. This feature cross-effect strains different strain stresses where all imposed directions. An increase anisotropy field or filler content, introduction silane coupling agent Mullins effect.