Shape Distortion of Carbon/Epoxy Composite Parts During Fabrication

摘要

The accurate modelling of residual stress in thermoset composites requires comprehensive consideration of all the phenomena contributing to its formation. These include: chemical shrinkage of matrix due to cross linking of molecules, mismatch of thermal expansion or contraction among fibres and matrix and viscoelastic relaxation during the fabrication. Thermo-physical and thermo- mechanical properties are altered during the curing process due to an exothermic chemical reaction. Since all the phenomena causing residual stress are strongly coupled, the solution procedure is a complex task. In this study, spring-in angle of carbon/epoxy woven composite bracket with three different thicknesses are calculated by simultaneously solving the thermo-kinetics and thermo-mechanics coupling by a finite element code COMSOL Multiphysics. Properties of composites required for numerical simulation are obtained using an analytical method. The spring-in angle values obtained by numerical simulation are also compared with the results of the analytical model.