Project

Carbon Fibre Reinforced Polymers (CFRP) are expected to be an important material for future light structural components in the automotive industry due to their high specific stiffness and energy absorption properties. However, for composites to be used to a larger extent in this type of components, the crashworthiness must be modelled and validated in order to fulfil the crash legal requirements. Since laminates made of unidirectional plies traditionally have been used in aircraft industry, much research has been performed on modelling of failure initiation and propagation. In the automotive industry, it is important that the manufacturing process is cheap and fast and because of that textile reinforcements are more suitable candidates than the unidirectional. In terms of modelling, the more complex geometry of textile reinforcements at the ply level compared to unidirectional plies has to be taken into account. In this project, a physically based constitutive model for textile reinforced composites will be developed.  In parallel, methodology for experimental characterisation of individual mechanisms and their energy absorption will be developed. During a crash event, the material will experience both crushing and large strains. The main focus will be compressive loads since they are most relevant in crash situations. FE-models on the bundle level of experiments performed within the project will also be a tool in order to better understand how the mechanisms interact. Due to the complexity of the deformation process, all mechanisms cannot be taken into consideration but the idea is to identify the most important ones and focus on them. The aim is to develop a constitutive model and methods for characterisation that are general and useful for a large range of textile reinforcements. However, in the project carbon fibre Non Crimp Fabric (NCF), also known as Multiaxial Warp-knitted Fabrics, are used together with epoxy matrix. The project is funded for four years by the Swedish Energy Agency and is performed in cooperation between Swerea SICOMP and Chalmers University of Technology.