Overmoulding ‒ An Integrated Design Approach for Dimensional Accuracy and Strength of Structural Parts

M.M. Bouwman, T.G. Donderwinkel, S. Wijskamp
ThermoPlastic composites Research Center, Enschede, The Netherlands

Abstract:
Overmoulding of thermoplastic composites combines the benefits of thermoforming and injection moulding to create structural parts with a high level of function integration. Work is performed in order to create proper design tools that can be used for a right-the-first-time design strategy. These tools take into account the evolution of residual stresses during forming, the development of the interface between the polymer and the composite during injection, and the warpage of the final part after cooling and release from the mould. A model is proposed for the prediction of the bond strength between an injected polymer and a composite insert. A test method has been developed to validate this bond strength under tensile loading conditions. A numerical strategy is proposed for the coupling between a forming and an injection moulding simulation. The spring-forward of different continuous fibre reinforced thermoplastic V-shapes was evaluated showing a good correlation between experimental work and a theoretical model.