Study on Cure Deformation of Metal/CFRP Laminated Composites

Abstract

Abstract During the curing process of composite materials, the differences of the heat transfer ability and mechanical properties of material in various directions result in residual stresses and curing deformation in the composite after curing. Curing deformation has adverse effect on the mechanical performance of composites. The development of internal stress during curing may cause matrix cracking, delamination, warpage and rebound deformation of composites. In this paper, numerical simulation is used to predict the curing deformation of components, thereby reducing production costs and improving production efficiency as well. According to the curing kinetic equation, the HETVAL subroutine was firstly developed to calculate the temperature field and the curing degree field of the curing process. UMAT and UEXPAN subroutines were then applied to solve the mechanical constants and thermal strain and curing shrinkage strain during the curing process. After the proposed model was verified, the deformation of the metal composite co-cured components was studied. It was found that when the thickness ratio of metal to CFRP is one to one the composite gains the greatest geometrical deviation after curing.