Impact on multi-layered polypropylene foams

Foams, and particularly the polypropylene foam, are more and more often used in the area of injury protection and passive safety for its energy absorption capacity. This multi-scale material is constituted of mesoscopic beads with a large variability of the material properties. To study the effects of these mesoscopic heterogeneities on both the macroscopic and the local behaviors, numerical simulations on virtual volumes of foam under dynamic loading have been performed. The influence of the organized system of heterogeneities has also been studied in the cases of a random distribution and a multi-layered volume. Experimental dynamic compressive tests have been performed on multi-layered volumes of foam and compared with the results of the Finite Element Method.

► To develop a numerical model of foam with heterogeneities using virtual volumes of foam. ► Study numerical trends about the influence of the beads density. ► Influence of the heterogeneities on the local behavior. ► Modification of the macroscopic behavior by the use of multi-layered foams. ► Improving energy-absorption with multi-layered foams.