|About this Abstract
||Materials Science & Technology 2019
||Materials for Nuclear Applications
||Computational Studies of Environmental Degradation of Silicon Carbide
||Izabela A. Szlufarska, Jianqi Xi, Cheng Liu
|On-Site Speaker (Planned)
||Izabela A. Szlufarska
One of the requirements for nuclear reactor applications of SiC is good corrosion resistance. While in oxidizing environments SiC can form a protective oxide layer, oxides typically do not form on SiC in molten salt or high temperature water. Here, we report ab initio molecular dynamics simulations of degradation of SiC exposed to corrosive coolants. For molten salts, we show that the standard dissolution potential for Si is smaller than that of C, indicating that Si is easier to dissolve than C in the salt. A swapping mechanism is identified for the initial corrosion stage, where Si first comes to the surface and then is dissolved, leaving behind a C-rich surface. We will also discuss our preliminary results of mechanisms underlying hydrothermal corrosion of SiC, where SiC is dissolved directly into the water. Finally, we will present simulation results on the coupling of radiation and oxidation effects in SiC.