The research on self repair of airplane components, under an SBIR phase II with Wright Patterson Air Force
Base, has investigated the attributes and best end use applications for such a technology. These attributes include issues
related to manufacturability, cost, potential benefits such as weight reduction, and cost reduction.
The goal of our research has been to develop self-repairing composites with unique strength for air vehicles.
Our revolutionary approach involves the autonomous release of repair chemicals from within the composite matrix
itself. The repair agents are contained in hollow, structural fibers that are embedded within the matrix. Under stress,
the composite senses external environmental factors and reacts by releasing the repair agents from within the hollow
vessels. This autonomous response occurs wherever and whenever cracking, debonding or other matrix damage
transpires. Superior performance over the life of the composite is achieved through this self-repairing mechanism. The
advantages to the military would be safely executed missions, fewer repairs and eventually lighter vehicles.
In particular the research has addressed the issues by correlating the impact of the various factors, such as 1)
delivery vessel placement, shape/size and effect on composite strength, chemicals released and their effect on the
matrix, release trigger and efficacy and any impact on matrix properties 2) impact of composite processing methods that
involve heat and pressure on the repair vessels. Our self repairing system can be processed at temperatures of 300-350F,
repairs in less than 30 seconds and does not damage the composite by repair fiber insertion or chemical release.
Scaling up and manufacture of components has revealed that anticipating potential problems allowed us to avoid
those associated with processing temperatures and pressures. The presentation will focus on compression after impact
testing and the placement of repair fibers/tubes into prepreg laminates.