Influence of Lode parameter on damage and fracture behavior of polyethylene materials

Abstract

AbstractIn this study, a series of tests on notched polyethylene (PE) plate specimens providing clues to damage and fracture behavior for a wide range of Lode parameters was carried out. Two series of numerical simulations of each test were performed, the first one without taking damage evolution into consideration and the second one taking damage evolution into consideration. Good correlation of experimental and numerical results in terms of the engineering stress–displacement relation has been achieved. The results show that the average Lode parameter increases with the increasing notch radius of the plate specimens. In addition, the damaged and undamaged constitutive equations were determined from the first and second series of finite element (FE) simulation, respectively. The critical damage parameter calculated from the damaged and undamaged constitutive equations was found to decrease when the average Lode parameter is increased. Furthermore, fracture occurs at the center of the minimum cross section, where the maximum damage parameter and plastic strain occur. The fracture strain was found to increase with the increase in the average Lode parameter.