Fracture analysis of low-density porous material by shear mechanics on ball indentation test

Abstract

The deformation mechanics of cloth are complex owing to its mesoscopic structure, and its destruction is one of the most intricate processes. In this study, the destruction of a low-density porous material is examined to gain understanding regarding its destruction, because this material has a simpler structure than cloth. In addition, it is useful to observe the fundamental destruction of a porous material similar to cloth. In this study, ball indentation is adopted because it can evaluate the mechanics without considering the directionality and fixing by pinching. In the ball indentation test of the low-density porous material examined herein, a plateau region is observed, in which the reaction force is nearly constant, and this force is larger than the value considered only for uniaxial compression. Numerical analysis is performed considering the shear fracture, and it validates the result of the plateau force obtained from the experiments. Furthermore, it is shown that the plateau force varies with the shear strain of the fracture.