Investigation On Curing Deformation Of Carbon Fiber Reinforced Resin Matrix Composites

Distortion and deformation would appear during the autoclave curing process of Fiber reinforced resin composites.Thermal strain,chemical strain,residue strain and resin flow are considered to be the main factors that lead to curing deformation.In the past investigations,the heat transfer and curing chemical process are considered to be two coupled process,while the effect of resin flow is considered separately,assuming that the resin has stopped flowing by the time that the chemical process begins.This assumption is valid when the thickness of the laminate is small,but if a thick laminate is of interested,the assumption is no longer proper,a fully coupled model should be established.This work integrated the resin flow model into the computation of the curing deformation of fiber reinforced resin composites,a fully coupled model is established in this work.A simulation of autoclave curing process of composites with single fiber direction(AS4/3501-6)is performed.The influence of resin flow on curing deformation is verified to exist.And the influence of in-plane size of laminate on resin flow is investigated.The result demonstrates.The resin flow during the curing process leads to a non-uniform resin distribution.In a single fiber direction composites,for instance,on a segment that vertical to the fiber direction,by the time of the end of curing,there would be more resin to the edge than that to the center.If some pressure is given to the side surface of the prepreg system,zero pressure on the top surface,and the put the autoclave pressure on from the begin,then the resin distribution would be much more uniform.The curing process of composites with different sizes are also investigated in this work,the result demonstrated that the in-plane size of composites part has influence on resin flow in composites during curing,which leads to a non-uniform resin distribution,a decreased number of fiber volume fraction,and finally leads to complex deformation.The simulation result verifies the importance of considering resin flow model in the simulation of composites curing process,and demonstrates how parts in-plane size influences the resin flow.The result could guide the design of composite parts and the parameters of curing process.