Deformation Behavior of Semi-crystalline Polymer in Mesoscopic Region under Different Stress States

Abstract

In the present study, we clarify the deformation behavior of semi-crystalline polymer in microto mesoscopic region by using large deformation finite element homogenization method. The crystalline plasticity theory using a penalty method for the inextensibility constraint in the chain direction and the nonaffine molecular chain network theory were used to the representation of the deformation behavior of the crystalline and amorphous phases, respectively, in the composite microstructure of the semi-crystalline polymer. The deformation behaviors of High Density Polyethylene (HDPE) in micro- to mesoscopic region under mesoscopically uniform plane strain tension, compression and shearing were investigated. The results revealed that the microstructure of semicrystalline polymer exhibits highly anisotropic deformation behavior including strain softening or substantial hardening. Furthermore, mesoscopically localized deformation zone intersepting several grains appears in the direction of maximum shear stress due to the interactions with surroundings.