Stress-Rupture of Epoxy-Coated Beryllium Wire

Stress-rupture data for epoxy-coated beryllium wire specimens under uniaxial tension loading are summarized and expressed in terms of fiber stress. A stress vs log time plot indicates the general trend of the stress-rupture behavior of this simple Be /epoxy composite. If it is assumed that the rate of stress-rupture is approximately constant, it is seen that this rate is such that a decrease in stress of about 5% increases the fiber life by a factor of 5. The Be/epoxy data has less scatter than that for S-glass, Kevlar 49, and Thornel 50 S because of its lower tensile strength variation.