High-throughput screening for high thermal conductivity SiC ceramic systems: Experimental and multiscale simulation investigation

Given the wide prospects for SiC ceramic with high thermal conductivity, high-throughput screening of SiC containing BeO-Y2O3-Al2O3-MgO additives has been implemented by the experimental and multiscale simulation investigation. About 16 groups of SiC prepared by SPS are composed of 4H-SiC, 6H-SiC, 3C-SiC, BeO and yttrium aluminum garnet phases, and exhibit equiaxed and columnar microstructures. It was verified by the density functional theory simulation that these dopants (Be, O, Mg, Al and Y) can migrate spontaneously towards the Σ13 (150) [001] GB. The ceramics with thermal conductivity higher than 120 W/(m⋅K) were screened out. Especially, the annealed SiC with 5%BeO-10 % additive exhibits the maximum thermal conductivity of 206.5 W/(m⋅K). The Vickers hardness about 16.89 GPa can be predicted by the macro finite element model simulation, which is accorded with the experimental result. This work provides an economically feasible project for the large-scale production of SiC ceramics with high thermal conductivity.