Dynamic fatigue properties of closed-cell non-crosslinked PE foams

The dynamic fatigue properties of commercial closed-cell/non-crosslinked po lyethylene (PE) foams were investigated for applications of structural load ing and packaging design. The compressive properties were studied in terms of maximum dynamic fatigue stress set at various void sizes, maximum test a mplitudes and test speeds, the results being compared with those obtained u nder static compression conditions. Local temperature rise under cyclic loa ding and dynamic compression set were also investigated. All the experiment al results were obtained using a universal tensile testing machine and the data were recorded using a high speed data logger coupled to a personal com puter. The static compressive stress was affected by test speed, but this w as not the case for maximum amplitude. These two variables were found to in fluence the maximum dynamic fatigue stress of the foam in association with increased fatigue in the material, excessive rupture of the cell structure and ductile-brittle characteristics of the foam.