|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Mechanisms Underlying Residual Stress Generation During the Oxidation of Silicon Carbide
||Ramanathan Krishnamurthy, Pavel Mogilevsky, Craig P Przybyla, Triplicane A Parthasarathy, Randall S Hay
|On-Site Speaker (Planned)
High temperature oxidation of SiC-containing turbine components generates residual stresses that lead to potentially life-limiting environmentally assisted cracking and failure. Currently, residual stress generation/ evolution during the thermal oxidation of SiC is poorly understood. Here, a combined experiment-modeling framework is introduced that provides new insight into the mechanisms of oxide formation and resultant stress generation. SiC plates are oxidized at several temperatures/time-periods where after laser interferometry is employed to measure plate deformation (or oxide mismatch strain) induced by the residual stress in the oxide. In parallel, an integrated modeling approach for SiC oxidation is introduced that incorporates the physics associated with oxidant/effluent diffusion, the oxidation reaction, stress generation and viscoplastic relaxation, respectively. Results for oxide stress evolution during passive oxidation in the 500-1000C range are presented. The combined results are used to draw insights on the dominant oxide stress evolution mechanisms and their impact on the failure of SiC structures.
||Planned: A print-only volume