Co-curing of thermoset composites on metal structures with reduced cycle times for high-volume car applications

Abstract

By locally reinforcing metal parts with fibre reinforced plastics, the mechanical behaviour can be increased significantly while adding only a minimum of weight. This technology has the potential for the introduction into high-volume car production due to i.e. the possibility to use conventional joining techniques of current car-manufacturing processes. Still the cycle time of this reinforcement process has to be decreased below 1 min to principally enable a further consideration in future car serial projects. This paper illustrates the evaluation of the reaction speed of an expedient epoxy matrix material and its mathematical description. The bonding strength of a unidirectional fibre reinforced semi-finished product, pre-impregnated with this matrix material onto a metallic surface is then evaluated by single-lap shear tests. The potential of this technology is validated using a locally reinforced metal hat profile, loaded under 3-point-bending. To evaluate the increase of performance, the energy absorption of these tested parts is calculated and compared with unreinforced metal profiles. Furthermore, the influence of compression time and pressure on the energy absorption was investigated. All the experiments are furthermore realized with two adhesives to demonstrates the influence of this additional material on the cycle times and the mechanical performance.