The properties that make plastic of direct interest to designers and engineers are its good strength to weight ratio, low manufacturing installation costs, and high durability. The strength of polymers is known to be sensitive to temperature and this generally limits their use under service temperatures. The present work addresses the effect of temperatures ranging from 0 to 70 on the shear properties of high-density polyethylene (HDPE) and polyvinyl chloride (PVC) materials. The results show that Yield stress increase with temperature by (15.4%) for HDPE and the temperature has no effect on yield stresses of PVC.
The modulus of elasticity varied in each temperature for both materials selected and the maximum shear strength, however, showed a slight increase in this temperature range by (1.4%) for HDPE but slightly decrease by (2%) for PVC. Shear rupture and elongation reduced by (0.02%) with increasing temperature by (1 °C) for both materials .Ductile fracture is observed to be the controlling failure mechanism at all temperatures of interest for both material and no data were recorded at 70 due to distortion of all specimens in this temperature selected.