Induction Bonding of Composite Armor

Thermoplastics are stable, high molecular weight polymers that retain their chemical structure during processing. Since fully polymerized thermoplastics do no form cross-linked networks, they can be softened, melted, and reformed. This program will demonstrate the induction bonding of composite armor materials by first incorporating a thermoplastic material onto the composite surface. Subsequent heating and melting of this surface will provide a strong adhesive bond between materials not typically associated with induction techniques. Foster-Miller has assembled a strong program team with technical strengths in adhesive bonding, composite fabrication, and induction processing with an industrial partner having a proven record in the manufacturing of composite vehicles and armor. As part of this effort, samples will be fabricated, processed, and characterized as a function of processing, to determine the effectiveness of both incorporating the thermoplastic onto the armor materials and the subsequent induction processing. Successful development of this method will provide a fast and cost-effective means to adhesively bond thick composite materials. A successful Phase I effort would demonstrate the feasibility of induction bonding of dissimilar materials through the incorporation of thermoplastic surfaces on the materials to be bonded. An advantage of an induction bonding method is the speed at which joints can be assembled. Fast bond time can be used to achieve maximum strength. Any system to which a thin layer of thermoplastic can be adhered prior to joining can make use of the developed technique. A simple induction processing/repair technique would have broad applications in the commercial aircraft, infrastructure, and transportation industries.