Evaluation of the crack shape and activation energy for fracture in double torsion fracture tests of high density polyethylene

摘要

The double torsion (DT) fracture geometry is finding increasing use in polymer research due to its many practical advantages. One of the most signifi-cant advantages is that DT is a constant stress intensity geometry, so the crack grows at a constant speed [1-4]. This makes DT particularly suited to the study of crack propagation. One common application of such studies is to evaluate the activa-tion energy for fracture.