Mechanical properties and failure mechanisms of closed-cell PVC foams

A comprehensive study of the mechanical behaviour of closed-cell polyvinyl chloride (PVC) foams with varying densities is conducted under tension, compression and impact loading. Experimental results on four classes of high-performance PVC foams show that the elastic modulus, strength and energy absorption of such foams are highly dependent on density. The compressive energy absorption is considerably higher than that under tensile loading. Impact resistance is found to increase linearly with foam density over the range of densities explored. In particular, it is demonstrated that the maximum impact energy and impact resistance are both attained by the PVC foam with the highest density. The impact test results are integrated with findings from high-speed camera and ultrasound imaging of failed specimens to explore the correlation between energy absorption and damage mechanisms. Experimental results on quasi-static behaviour are interpreted using available modelling tools for closed-cell foams to establish design guidelines.