Stress Rupture of Ceramics: Time-Temperature Relationships

Abstract

Ceramic materials, such as Silicon Carbide and Silicon Nitride, have been considered as replacements for metals in many components of modern engines, as opportunities have arisen to make use of their unique properties. Improved production capabilities and end-product defect control have contributed to this progress, but limited information on the effect of these parameters on long term behavior, such as creep and stress rupture, may have contributed to some of the difficulties. This paper will examine the stress-rupture behavior of some ceramic materials, to demonstrate a unique relationship between the time to failure, at a given stress, and the temperature. The outcome is a single parameter combining the time to failure and temperature variables, which can allow designers to predict the useful life of ceramic components more accurately than insufficient data would otherwise allow.