Testing of Graphite Composites in Air at High Temperatures

Abstract

Extreme environments associated with atmospheric re-entry require materials capable of withstanding severe thermal and mechanical conditions. Generally, data available from tests made under amibient conditions of previously oxidized material, or from tests of materials made at elevated temperatures in an inert atmosphere e, do not relate well to properties of materials in the actual re-entry environment. Procedures were developed for high temperature testing in air. The loss of material with time was measured and correlated with observed strength data. Shapes of temperature-strength curves for oxidized JTA graphite were similar to those obtained under inert conditions. As anticipated, strengths after oxidation were lower, depending on the length of exposure.