Effect of fibre direction and stacking sequence on dynamic impact performance of composite bicycle frame

Abstract

ABSTRACTLightweight and safety performance are two important factors for bicycle design. For a composite bicycle frame with given geometry size, the material design is a new method to improve its dynamic impact performance. Since different levels of impact are generated among different parts, different parts with different fibre directions and stacking sequences are considered for each part. In this study, the effect of fibre direction and stacking sequence on dynamic impact performance of composite bicycle frame has been discussed. A three-dimensional solid model of bicycle frame is constructed and the low-velocity impact finite element simulations for the CFRP bicycle frame are performed via ANSYS/LS-DYNA. In addition, the energy absorption capabilities and dynamic response characteristics of the CFRP bicycle frame are investigated. It can be found from results of the finite element simulations that, three relatively optimal lay-up schemes with minimal permanent deformation are obtained and the corresponding bicycle frame specimens are manufactured. Through impact experiments and finite element analysis, finally, the optimal lay-up scheme (Case 1, stacking A:[(±45°)4], stacking B:[(±45°)2/0°]) with minimal permanent deformation is obtained. The stacking sequence has little effect on dynamic impact performance. Furthermore, proportion of layers with different fibre directions has an obvious effect on impact performance, and a higher proportion of layers with ±45° fibre directions improve the impact performance.