Engineering specialist, Mail Zone 2860, General Dynamics, Forth Worth, Tex.
Pages: 12 Published: Jan 1978
Recent investigations have shown that absorbed moisture lowers glass transition of epoxy resin more than indicated by currently accepted models. The resulting glass transition value limits supersonic service conditions. This limitation results because exceeding glass transition causes the “thermal spike effect” and greatly reduces the strength of graphite-epoxy. These circumstances are reviewed and used to show the importance of realistically simulating airfield humidity and flight temperatures during testing. A new, economical approach is described for simulating realistic humidities for large structures.
epoxy matrix composites, humidity, glass transition temperature, service envelope, environmental simulation, composite materials
Paper ID: STP34864S