Fracture Behavior of Graphite Material at Elevated Temperatures Considering Oxidation Condition

Title & Authors
Fracture Behavior of Graphite Material at Elevated Temperatures Considering Oxidation Condition
Choi, Hoon Seok; Kim, Jae Hoon; Oh, Kawng Keun;

Abstract
Graphite material has been widely used for making the rocket nozzle throat because of its excellent thermal properties. However, when compared with typical structural materials, graphite is relatively weak with respect to both strength and toughness, owing to its quasi-brittle behavior, and gets oxidized at $\small{450^{\circ}C}$. Therefore, it is important to evaluate the thermal and mechanical properties of this material for using it in structural applications. This study presents an experimental method to investigate the fracture behavior of ATJ graphite at elevated temperatures. In particular, the effects of major parameters such as temperature, loading, and oxidation conditions on strength and fracture characteristics were investigated. Uniaxial compression and tension tests were conducted in accordance with the ASTM standard at room temperature, $\small{500^{\circ}C}$, and $\small{1,000^{\circ}C}$. Fractography analysis of the fractured specimens was carried out using an SEM.
Keywords
ATJ Graphite;Oxidation;Uniaxial Compression;Uniaxial Tension;Silicon Carbide;Oxidation Protection Coating;SEM;
Language
Korean
Cited by
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