Infrared curing simulations of liquid composites molding

Infrared radiation is an effective energy source to cure thermosetting polymers. Its usage is expected to reduce curing time in comparison with thermal heating and mold thermally regulated. In addition, because of the polymerization mechanism and instant on-off control of this power, an improvement in the final properties of the material is also expected. In this paper, we studied the infrared interaction with carbon (or glass) fibers reinforced epoxy matrix, where Liquid resin infusion (LRI) is used to manufacture the composite. Temperature of the composite is a key parameter that affects its mechanical properties and is controlled by the infrared emitters and the exothermic heat released from the polymerization. Radiative heat flux is computed using the in-lab developed software RAYHEAT. Then, the heat flux (or absorbed energy for glass fibers) is exported to the finite element based program COMSOLMULTIPHYSICS where heat balance equation is solved. This equation is coupled with the exothermic heat released during the curing process in order to predict the composite temperature versus time and degree of cure. Numerical simulations will be performed on planar parts (sheet shape) as well as curvilinear shapes. Experimental validations of the infrared curing carbon (glass)-epoxy composite system are presented in this paper Sheet surface temperature distribution are measured thanks to infrared camera. Kinetic parameters were estimated from differential scanning calorimeter (DSC) experimental data.