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During side impact, door panels must be designed according to the original equipment manufacturer's passive safety requirements to reach good European New Car Assessment Programme scores. The energy produced during the shock must be absorbed and no fracture of contactable parts should appear. To design the best solution, numerical finite element codes are used and predictability of the calculations is necessary to converge directly to the safest concept. This paper shows a great improvement in the calculation accuracy by modelling the behaviour of links between parts. Polymer rivet and snap behaviours are discussed and a methodology for samples is described. It is now possible to detect and to reinforce design in risk areas with crash simulations to avoid any breakage of the door panel assembly. Finally, a validation of the door panel is highlighted by comparing experimental results and numerical simulation predictions.

The increasing complexity of interior vehicle design means that more powerful finite element models are needed to simulate the crash behaviour of dashboards, door panels and even trim panels. The knowledge of the behaviour of structural components is essential for their design optimisation. Constitutive models describe their material behaviour in finite element codes. The models are in relation with material parameters, which have to be determined. An inverse numerical approach using the results of experimental dynamic tests of polymer samples has therefore been developed to determine these parameters. This inverse method is used to identify the parameters of G'Sell's law taking self-heating and mould flow direction into account. The thermal influence on the mechanical behaviour is studied. The influence of the anisotropy due to the direction of the flow during the filling of the mould is discussed too. The results are compared with the results obtained by classical dynamic uniaxial tensile tests...