Mesoscopic simulation on curing deformation and residual stresses of 3D braided composites

Abstract

Both cure deformations and residual stresses of 3D braided composites are studied based on the representative volume element (RVE) by means of thermochemical and thermodynamic model. First, the curing analysis model of cubic braided RVE is established, and the HETVAL, UMAT, UEXPAN and USDFLD subroutines are used to define the properties of the resin and the fiber about curing reaction kinetic, thermal conductive and viscoelastic model, respectively. Second, both thermochemical and thermodynamic behaviors of the RVE in 3D braided composites are simulated and analyzed which indicates the relationship among curing process, deformation and residual stress in mesoscopic scale. Finally, the influences of temperature rising rate and curing temperature on degree of curing, curing deformation and residual stresses of 3D braided composites under different curing process are investigated. These results will play an important role for designing curing technology and evaluating the residual stress in 3D braided composites.