SAE International Impact Deformation and Fracture Morphology of a Multi-layer HDPE Material 2008-01-1287

This paper investigates the impact deformation and fracture of a co-extruded multi-layer polymeric material. The material consists of a layer of ethylene vinyl alcohol, EvOH, two layers of linear low density polyethylene (LLDPE) based adhesive and three layers of high density polyethylene (HDPE). The multi-layer material was driven dart impact tested with velocities of 0.4 m/sec and 4.0 m/sec at 23°C and -40°C temperature conditions. The fracture morphology of the material was studied using scanning electron microscopic (SEM). An increase in energy absorption up to the maximum load was observed at -40°C; whereas, the total energy absorption decreased when compared to those tested at ambient temperature conditions. SEM observation revealed that the EvOH layer was the major contributor to the reduced ductility of the multi-layer system.