TITLE:
Synthesis of MgSiN2 Powders from the Mg-Si System
AUTHORS:
Ran Guo, Xuemei Yi, Xiongzhang Liu, Qingda Li, Takahiro Nomura
KEYWORDS:
Nitride Materials, Crystal Growth, X-Ray Diffraction, Mg-Si System
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.6 No.1,
January
29,
2018
ABSTRACT: Magnesium silicon nitride (MgSiN2) was synthesized without any additives under a nitrogen gas flow (200 mL/min) using a nitriding method. The effects of temperature and holding time on its purity and morphology were investigated. A single-phase MgSiN2 powder was obtained at 1350℃ for 1 h and 1250℃ for 11 h. However, the decomposition of MgSiN2 occurred at 1450℃, suggesting that the optimum temperature for the preparation of MgSiN2 from Mg-Si system was 1350℃. The phase purity, morphology, size of the product and elemental composition of the samples were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy spectrometer (EDS), respectively. The evaporation of Mg and Si resulted in the formation of many voids in the blocky product. The temperature gradient promotes the growth of MgSiN2 on the surface of massive products along the tip. The concentration gradient of Mg and Si vapors in the void resulted in the columnar growth of MgSiN2.