Crush simulation of automotive chopped fiber composite structures by de-homogenization multi-scale computational method

摘要

A de-homogenization multi-scale computational method is proposed for the virtual performance simulation of chopped fibers composites under crush loadings. The novel approach led to the development of a multi-scale material characterization procedure for composite systems, comprising of: (1) chopped fibers homogenization based on the Eshelby and Mori-Tanaka inclusion theories, (2) orientation tensor stiffness averaging technique, (3) micro- and macro-mechanics damage and failure theories, and (4) crush resistance evaluation, as a part of the durability and damage tolerance analysis. The chopped fibers material model developed in this work is then employed in a finite element analysis, interfaced with a multi-scale progressive failure technique to track damage and fracture evolution. Comparison of the simulation results obtained for two tubes, manufactured by injection and compression molding respectively, shows good agreement with the crush test data within 10% accuracy. The proposed de-homogenization method offers a superior load resistance prediction over commercially available techniques. Furthermore, the implementation of the proposed approach in our in-house software provides traceable damage evolution and visualization of the contributing failure mechanisms, valuable sources for the design and development of new composite structures.