Investigation on heating behavior during the preparation of SiC crystals by microwave sintering

Abstract

β‐SiC powders were synthesized by microwave sintering at 1400‐1850°C for 60 minutes with coal minerals. Raw materials were prepared with a sol‐gel method by coating SiO2 on coal mineral particles, and microwave sintering was conducted in a microwave chamber with TE666 resonant mode. Heating rates were controlled by input microwave power and heating behavior during the microwave sintering was also investigated. XRD, SEM, Raman, TEM techniques were carried out to characterize samples. It was found that different particle size of coal mineral particles gave rise to different heating effect, leading to different growth mechanisms of SiC crystals. This might be the unique features for microwave sintering. Particular SiC crystals dominated for small coal mineral particles, which attributed to microwave plasma effect. While SiC whiskers or fibers dominated for large coal mineral particles, which corresponded to microwave coupling effect. Microwave coupling effect prevailed for low heating rate which was apt to form particular SiC crystals. Whereas, higher heating rate enhanced microwave plasma and primarily resulted in SiC whiskers or fibers.

Microwave-Assisted Preparation of Luminescent Inorganic Materials: A Fast Route to Light Conversion and Storage Phosphors

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“…Microwave dielectric properties (tan δe and dp) and average heating rate of selected susceptor materials. The values are from the references[76,[79][80][81].…”

Preparation of cubic SiC from δ-Na2Si2O5/carbon nanocomposite using cobalt catalyst

“…Microwave has also been used to prepare SiC because of its advantages of rapid heating, energy saving, environmental protection and lower synthesis temperature [20][21][22][23]. However, most of the raw materials that were used to prepare SiC powders by microwave sintering were obtained commercially with little characterization, and the SiC crystal growth mechanism by microwave sintering remains ambiguous.…”

Effect of atmosphere on the fabrication of Si2N2O matrix composites

“…As an advanced materials preparation technology, microwave sintering has attracted considerable attention in the field of fabrication of high temperature materials [1][2][3][4][5]. Technological innovation and theoretical breakthrough of wave-transparent composites are imperative for the development of microwave sintering technique.…”