Improved Resin Injection Repairs for Polymer Composite Materials

Defective and damaged composites are costly to replace, and current repair materials and techniques are inadequate to restore maximum strength. The development of an effective repair resin coupled with a simplified repair method will allow CH-53K composite parts to be repaired in factory or field settings. Texas Research Institute Austin Inc. (TRI/Austin) proposes a novel repair resin that will provide a room temperature cure, excellent mechanical and environmental properties, and exceptional adhesion to unprepared, contaminated surfaces. A very low viscosity will ensure that the resin fully wets out the damaged surfaces upon injection in order to fill in all voids. In-house advanced nondestructive testing methods will be used to map defects in CH-53 parts during injection repair demonstrations in Phase I. Adhesion, flexural modulus, in-plane shear, elastic modulus, interlaminar shear strength, fatigue, and fluid and temperature resistance of test specimens and repaired composites will be evaluated. During Phase I, TRI/Austin will work with Abaris Training, Inc., a leader in composite repair methods, and ITT Exelis, a manufacturer of CH-53K composite components. ITT Exelis will provide Phase I repair validation specimens, using Sikorsky/Navy approved fabrication procedures, as well as guidance that will ensure repair integration on the shop floor.