Corrosion behavior of pressureless-sintered SiC in molten NaCl-KCl-MgCl2 salt at 700 degrees C
PUBLICATION: SOLAR ENERGY MATERIALS AND SOLAR CELLS
AUTHORS: Wang, Xiaodong; Yang, Xinmei; Hu, Miaomiao; Liu, Huajian; Liu, Shulin; Zhou, Xingtai
The corrosion behavior of pressureless-sintered SiC in a molten NaCl-KCl-MgCl2 salt at 700 degrees C was investigated. Results indicate that it is prior for SiC and sintering aid B around grain boundaries to be corroded. MgCl2.xH(2)O(x = 4,6) in the salt plays an important role in the corrosion of SiC. MgCl2.xH(2)O is hydrolyzed to HCl, H2O, and MgO, which react with SiC and B to form C, SiO2, SiCl4, B2O3, and Mg2SiO4. The corrosion depth of SiC and the concentrations of elements Si and B in the salt increase with the corrosion time, which are fitted well with Fick's law of diffusion.