Gap filling for thermoplastic welds

Abstract

Thermoplastic welding is an emerging technology targeted at significantly reducing the cast of manufacture of aerospace structure by eliminating fasteners and the touch labor associated with fasteners to prepare, install, and inspect the assemblies. Thermoplastic welds, however, suffer from significant residual tensile strain caused by differences in the coefficient of thermal expansion between the carbon fiber reinforced composite laminates and the unreinforced weld. Holding fiber reinforcement to the weld using a structural susceptor which is a laminate of alternating layers of thermoplastic resin and fiber reinforcement sandwiching a conventional metal susceptor alleviates this strain. The structural susceptor can be peeled in selected locations to fill the gap between the laminates, eliminating costly profilometry of the faying surfaces and the associated problem of resin depletion where machining occurred to match the faying surfaces. The peeled susceptor is complementary in contour to the gap it will fill.

Dependencies are inferred from the claim text.