Axial creep tests of a 10vol% boron-aluminum hotpressed monolayer composite were carried out under several constant loads at 300°C in air. The composite behaved with slight primary creep, but did not show appreciable secondary creep. Several specimens encountered a momentary increase of strain during the creep test which separated the creep curve into two regions, because of the individual fiber breaks in the composite. And then, almost all the specimens suddenly fractured without tertiary creep. From the viewpoint of reliability engineering the statistical properties of the creep-rupture time were investigated. The average creep-rupture time decreased with an increase in the applied stress, and the relatively large coefficient of variation was estimated in every case, being around 1000%. However, these scatters were estimated to be smaller than the scatter of the creep-rupture time in the boron fiber itself. That means, the reliability of the fiber's creep-rupture time is improved by compositing with matrix material.
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