Project structures engineer, General Dynamics, Fort Worth, Tex.
Pages: 17 Published: Jan 1977
Over 200 tests were performed to study the effects of moisture and temperature on typical graphite-epoxy bolted joints. Three test specimen types were used: unnotched control laminates, filled-hole specimens containing an unloaded fastener, and bearing specimens. Five typical laminate orientations were studied. Standard 1/4-in. straight-shank fasteners were used with bolt torques varying from zero to specification values. Two types of moisture conditioning were employed: hygrothermal and conditioning with thermal spikes to 300°F superimposed on the hygrothermal background. Test temperatures were 75 and 200°F. A summary of results shows that many of the test conditions produced no significant effects. The maximum reduction from room temperature, dry performance to hot, wet performance was 18 percent.
composite materials, laminates, joints (junctions), mechanical properties
Paper ID: STP26962S