Lightweight design of carbon twill weave fabric composite body structure for electric vehicle

Design of composite appears more challenging compared with metallic counterparts because of its microstructural heterogeneity and behavioral sophistication. This paper aims to develop a multiscale approach for predicting three-dimensional elastic model of carbon twill weave fabric composite which will be applied to crashworthiness analysis of body structure of electric vehicle. The geometric parameters were obtained by measuring the microstructure of T300 carbon twill weave fabric composite through optical microscopy. The finite element model of representative volume element (RVE) in laminate composite was established to characterize the elastic properties of the materials using the homogenization technique. The numerical results of property were compared with those from uniaxial tensile and three point bending tests. Finally, the constitutive model of such composite was employed to crashworthiness analysis for electric vehicle body structure under the roof crash and side pole impact. The study indicates that the deformation behaviors of laminate calculated by using the elastic properties are in good agreement with tensile and bending experimental results with maximum relative errors of 4.04% and 7.79%, respectively. Meanwhile, a 28% savings of body weight is achieved using the carbon twill weave fabric composite compared to its predecessor made of glass fiber reinforced plastics (GFRP).