Experimental study of creep behavior of high-density polyethylene and stress triaxiality effect

In a previous work, we presented a study of mechanical behavior of the high-density polyethylene (HDPE) under several types of stress: Tensile, compression, shear and biaxial loading; and we have shown the hydrostatic pressure effect on polyethylene yield behavior [1]. In order to complete it, the creep behavior of this material at different stress level is investigated experimentally at constant strain rate and at ambient temperature. The first objective is to determine the different stages of creep as a function of the applied stress and to explain the deformation mechanisms of the material occurring during each stage. Similarly, the sensitivity of creep to stress triaxiality is the subject of our investigation by the use of axisymmetric notched bar specimens with different radii. © 2019, Politechnica University of Bucharest. All rights reserved.