Growth Process of SiC Grains Prepared by High-energy Microwave Irradiation

Abstract

High-energy vacuum microwave irradiation was directly applied to synthesize silicon carbide (SiC). Results indicated that the well-crystallized β-SiC grains can be obtained rapidly and conveniently via microwave approach, even simply constituents covering silica dioxide powders and artificial graphite were employed as raw materials. Based on the comprehensive micro-structural characterizations, the formation of β-SiC, under high-energy vacuum microwave irradiation, could be properly explained by the mechanism of two-dimension nucleation and growth. Be- sides, the technology of electron backscattered diffraction (EBSD) was particularly used to characterize the crystal plane of the observed SiC grains. The corresponding calculation of Euler angles suggested that the fastest-growing crystal planes {211} should be overlapped gradually, and the evolution from {211} to {220} crystal planes should be realized through the formation of {421} transformation plane. The most stable crystal planes of {111} became the regular hexagonal planes in the end, which can be explained by the Bravis rule. Correspondingly, the {220} crystal planes were finally existed as the side-planes of SiC grains. The detailed EBSD investigation provided the experimen- tal evidences for the evolution of crystal planes in the growth process.