Improved Resin Injection Repairs for Polymer Composite Materials

Composite structures are often damaged during manufacturing or in service. Depending on the level of damage, the part will require repair or replacement to make operable and safe for flight. While there are many different types of repair methods, resin injection offers a less intrusive method of repair and does not require near the post-processing of other methods. However, this method of repair has usually only been utilized for cosmetic purposes and has not allowed the complete restoration of the structural performance of the part. This is due to many reasons including the repair resin rheology and wetting, compatibility and reactivity of the repair resin to the substrate, and mechanical properties. Accordingly, a resin having the necessary viscosity, wetting, and adhesion characteristics along with aircraft matrix mechanical properties would make a unique resin injection repair material that could enable restoration of the performance of the damaged part to its original capability. This would initially find significant use in reducing costs associated with manufacturing related flaws such as those occurring in the development program of the CH-53K heavy lift helicopter as well as other Navy aircraft.