Rapid-Cure Liquid Shim

Period of Performance: 12/15/2003 - 06/15/2004


Phase 1 SBIR

Recipient Firm

TDA Research, Inc.
12345 W. 52nd Ave. Array
Wheat Ridge, CO 80033
Principal Investigator


The U.S. DoD and several of our allies have designed and developed an advanced military fighter aircraft, the Joint Strike Fighter (JSF). During assembly, a liquid shim epoxy paste is applied before joints are mechanically fastened to make the joined surfaces fit tightly, thereby strengthening the joints and making them more durable. The current liquid shims provide excellent physical properties (particularly adhesive and compressive strength) but typically require 24 hours to develop a suitable handling strength and up to 5-7 days for full cure at ambient temperature. Unfortunately, this long cure time results in a bottleneck for JSF manufacture. To remove the bottleneck, the JSF program requires a new liquid shim material that maintains the excellent properties of the current materials but cures in less than two hours. TDA Research, Inc. (TDA) proposes to adapt our novel epoxy curatives to develop a high-strength, rapid-cure liquid shim. In this project, we will demonstrate feasibility by preparing curatives, formulating them into rapid curing epoxy liquid shim pastes, and testing the shims' mechanical properties in accordance with Aerospace Material Specification 3726.