US Patent 8647548 Method and system to reduce porosity in composite structures

In an embodiment of the disclosure, there is provided a method to reduce porosity in a composite structure. The method adds an additive to a resin material to form an additive-resin mixture. The method combines the additive-resin mixture with reinforcement fibers to form a composite prepreg material, and in turn, a composite structure. The method heat cures the composite structure in a heating apparatus under a vacuum device at the resin cure temperature, heats the composite structure to an increased temperature above the additive phase transition temperature, and maintains the increased temperature for a time period sufficient. The method reduces the increased temperature back down to the resin cure temperature to allow the additive gas to undergo a phase transition to a condense phase, resulting in a substantially reduced vacuum pressure, resulting in a reduction in a porosity of the composite structure.