Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8948528 | Journal of the European Ceramic Society | 2018 | 9 Pages |
Abstract
The Y3Si2C2 coating was in-situ synthesized on the surface of SiC powders to form SiC-Y3Si2C2 core-shell structure by using a molten salt technique. Phase diagram calculations on Si-Y-C ternary phase at different temperatures well illustrated that the Y3Si2C2 phase can be stable with SiC but will be in liquid state at 1560â°C. The liquid Y3Si2C2 explained the enhanced consolidation of SiC ceramics and its disappearance after spark plasma sintering. Such Y3Si2C2 coating could not only effectively improve the sintering, but also their mechanical and thermal properties of resultant ceramics. Typically, at 1700â°C, the bulk SiC ceramic presented a mean grain size of 2.5âum and relative density of 99.5% when the molar ratio of Y to SiC is 1:4 in molten salts; the Young's modulus, indentation hardness and fracture toughness measured by indentation test were 451.7âGPa, 26.3âGPa and 7.9âMâPam1/2, respectively; the thermal conductivity is about 145.9âW/(mâK). Excellent thermal and mechanical properties could be associated with the fine grain size, optimized phase composition and improved grain boundary structure.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Junqi Shao, Mian Li, Keke Chang, Ying Huang, Donglou Ren, Ji Wang, Xiaobing Zhou, Liu He, Feng Huang, Shiyu Du, Jianjun Sha, Zhengren Huang, Qing Huang,