Deformation and residual stresses during curing of hot-melt impregnated phenolic resin/glass fabric composite

The environmentally friendly and low-cost hot-melt impregnated method was utilized to prepare phenolic resin/glass fabric (MPF/GF) prepreg and composite. The curing kinetics and model of the hot-melt phenolic resin (MPF) were characterized. The viscosity of MPF as a function of cure temperature was investigated using the Arrhenius model. Based on the mutual interactions of heat transfer-cure, flow-compaction and stress-distortion during the curing process of hot-melt MPF/GF composite, as well as by taking into account the viscoelastic effect, three-dimensional finite element analysis model for the numerical simulation and prediction of the deformation and bending modulus of MPF/GF composite was established. Via calculating the temperature distribution and degree of cure of MPF/GF composite in different locations and at any cure time, the curing cycle including heating rates, holding time and different cooling rates can be optimized with finite element method. As a result, both the curing deformation and the residual stress of MPF/GF composite were reduced by 6.37% and 2.4%, respectively.