A Comparison of Thermoplastic Composite vs.Conventional-Steel Instrument Panel Systems for Side-Impact Energy Management

This paper discusses the contribution of instrument panel systems in a European side-impact event. Systems studied include a conventional steel cross-car beam system and a glass-mat thermoplastic (GMT) composite system, evaluated in a body-in-white structure. A thermoplastic composite instrument panel system offers mass, cost, and recycling benefits, but its performance vs. a conventional steel cross-car beam system merited an engineering investigation. The comparison methodology used included a nonlinear dynamic side impact study with a moving, deformable barrier developed according to European Economic Community (EEC) standards. A finite-element model used in this study simulated the body-in-white structure, barrier structure and instrument panel systems. The resulting data include velocity, displacement and energy absorption levels of various components of the respective instrument panel systems. In addition, data representing body-in-white performance relating to occupant injury parameters are discussed. The data show that a thermoplastic composite system can be expected to absorb more energy in critical areas, compared to a conventional steel cross-car beam system. Further study for additional crash information should be performed, as well as comparative analysis with injection molded structures.