An Adhesive Bonded Polymer-Metal Hybrid Hood Development: Design Engineering and Prototyping

The development of an automotive hood for an electric vehicle based on a polymer-metal hybrid configuration is described in this paper. Here, special focus is given only to the engineering design and prototyping phases which are the initial stages of a much bigger project. A project that aims to evaluate the cost efficiency, weight penalty and structural integrity of adopting polydicyclopentadiene as an exterior body material in low production volume vehicles, among them the electric ones.

For the engineering design and prototyping phases, three different reinforcement geometries were developed and six mechanical simulations were done through finite element analysis to aid best frame geometry selection and optimization. The entire hood was then prototyped containing the optimized geometry. The fabrication of the frame was made through metal stamping and the exterior panel through reaction injection moulding. Adhesive bonding was used for its assembly. The development of the tooling used for prototyping is also described in this paper. A dimensional control was made, in the end, over the metallic frame by using a 3D scanning equipment in order to measure any possible geometrical divergence caused by its fabrication.