Analysis of strain bursts during nanoindentation creep of high-density polyethylene

Systematic studies were conducted of discrete deformation processes occurring during nanoindentation creep of polyethylene with respect to load and loading rate, indicating dislocation-mediated plasticity. Nanoindentation creep experiments on polyethylene were carried out in order to investigate dislocation-based plastic deformation mechanisms. Similarly to that reported in a recent paper (Li J and Ngan AHW, Scr Mater 62:488-491 (2010)), discrete deformation processes occur during nanoindentation creep tests which again seem to arise from the break-off of dislocation avalanches. That interpretation is supported from systematic studies of the effect of variations of the loading rate and of the applied load on the number and the height of bursts.