This study reports on the formation of 25Mg-bearing precipitates and voids in cubic phase silicon carbide (3C-SiC) single crystals implanted to 9.6×1016 25Mg+/cm2 at 673 K and subsequently annealed at 1073 and 1573 K for 2, 6 and 12 h in an Ar environment. Unidirectionally aligned tetrahedral precipitates are observed around the Mg profile peak, many of which are likely cubic MgC2 and tetragonal Mg2Si particles or their precursor structures. There is also evidence that suggests a possible formation of core (MgC2)-shell (Mg2Si) structure in some of the large precipitates. In addition, small spherical voids are observed near the surface, along with the larger faceted voids in the region of maximum vacancy concentration. 25Mg segregation takes place with a dominant fraction of small atomic clusters. The study provides important results needed to fully assess SiC for potential fusion applications.
Revised: July 25, 2020 |
Published: December 31, 2017
Citation
Jiang W., S.R. Spurgeon, J. Liu, D.K. Schreiber, H. Jung, A. Devaraj, and D.J. Edwards, et al. 2017.PRECIPITATES AND VOIDS IN CUBIC SILICON CARBIDE IMPLANTED WITH 25Mg+ IONS. In Fusion Materials Semiannual Progress Report For Period Ending December 31,2017, edited by FW Wiffen and S Melton. 73-74. Oak Ridge, Tennessee:OAK RIDGE NATIONAL LABORATORY.PNNL-SA-132445.