Creep and Stress Rupture Testing of Polyethylene Sheet under Equal Biaxial Tensile Stresses

Abstract

A medium density (approximately 0.94 g/cm3) polyethylene sheet, approx imately 1.5 mm thick, was subjected to equal biaxial tension stresses by way of an axisym metric loading system. Tests were conducted at room temperature and at loads of ≤60% of the product's short term ultimate load capability to generate creep data under this load ing regime. Tests were also carried out at 60 and 80°C to evaluate the stress rupture char acteristics of the product. The experimental apparatus and test conditions are described. Creep data are presented in the form of isochronous stress-strain curves. Stress rupture data for ductile yelding failures are also presented.