Numerical study of the behaviour of composite mixed adhesive joints under impact strength for the automotive industry

Abstract

The increasing use of composite structures in the automotive industry is due to strict regulations regarding both fuel efficiency and safety standards, since this kind of structures allow to produce strong yet light vehicles. The main advantage of the use of adhesives is the possibility of joining dissimilar materials, particularly composite materials, representing an optimal method in comparison with more traditional ones such as fastening or welding. This work focused on the development and validation of numerical models able to simulate the performance of previously experimentally tested joints. The experimental tests were performed to assess the improvement of quasi-static and impact strength of composite adhesive joints, and with the focus of avoiding early delamination of the composite substrates. The technique selected for this purpose was the use of mixed adhesive joints. Mixed adhesive joints combine two or more adhesives in a single lap joint and combine these properties to attain mechanical performance superior to that obtained using those adhesives individually. The numerical results demonstrated to be able to simulate the experimental results with reasonable accuracy.