Abstract
The development and use of a finite element material model reflecting the dynamic material characteristics of expanded polypropylene are discussed. Attention is focused on the influence of impact velocity, shape, foam density and bottoming-out of the energy absorber. The obtained know-how allows the optimisation of integrated passive safety systems which incorporate structural and energy absorbing expanded polypropylene foam elements.
The in-depth studies, carried out by JSP International on an actual instrument panel clearly illustrate the benefits of finite element analysis in the tailoring of innovative materials and processing technology. An integrated padding in expanded polypropylene provides the structural base element where functional parts can be attached and offers an excellent absorption medium where the performance criteria for the head impact are optimised.
An excellent agreement with experimental results makes the JSP International thermoplastic foam material model an effective engineering tool allowing automotive development engineers to simulate expanded polypropylene foam in occupant safety and dynamic impact applications.