Formation of Silica-Coated Carbon Powder and Conversion to Spherical β-Silicon Carbide by Carbothermal Reduction

In this paper, we focus on the phase behaviors of talc minerals by carbothermal reduction (CR) method. The effects of temperature and carbon addition are both discussed in our work. In the experiment, acid-leaching talc was employed as raw material, carbon coke powders were adopted as reducing agent. The XRD results show that: When acid-leaching talc was used as raw material, quartz and few enstatite can be obtained at 1300 °C, with the temperature increasing, the diffraction intensities of enstatite increased. At 1550 °C, enstatite transformed to magnesium silicate and obvious β-SiC can be detected. At 1600 °C, the main phases in the final product are magnesium silicate and β-SiC. The SEM results reveal that the preferred, as-fabricated silicon carbide has morphology of irregular shape. Relatively pure β-SiC can be obtained by using acid-leaching talc mixed together with excess 50% of theoretical quantity of carbon powder sintered at 1550 °C for 4 h.

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The preparation of boron-doped silicon carbide powder by the carbothermal reduction of oxides derived from the hydrolyzed methyltriethoxysilane

Journal of Non-Crystalline Solids ◽

10.1016/0022-3093(88)90080-4 ◽

1988 ◽

Vol 100 (1-3) ◽

pp. 542-546 ◽

Cited By ~ 9

Author(s):

Yoshiyuki Sugahara ◽

Yasuharu Takeda ◽

Kazuyuki Kuroda ◽

Chuzo Kato

Keyword(s):

Silicon Carbide ◽

Carbothermal Reduction ◽

Carbide Powder ◽

Boron Doped ◽

Doped Silicon ◽

Reduction Of Oxides ◽

Silicon Carbide Powder

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Characteristics of Silicon Carbide Nanowires Synthesized on Porous Body by Carbothermal Reduction

Journal of the Korean Ceramic Society ◽

10.4191/kcers.2018.55.3.10 ◽

2018 ◽

Vol 55 (3) ◽

pp. 285-289 ◽

Cited By ~ 3

Author(s):

Jung-Hun Kim ◽

Sung-Churl Choi

Keyword(s):

Silicon Carbide ◽

Porous Body ◽

Carbothermal Reduction

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Fabrication of Silicon Carbide from Rice Husk by Carbothermal-Reduction and In Situ Reaction Bonding Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.608.235 ◽

2014 ◽

Vol 608 ◽

pp. 235-240 ◽

Cited By ~ 2

Author(s):

Chalermkwan Makornpan ◽

Charusporn Mongkolkachit ◽

Suda Wanakitti ◽

Thanakorn Wasanapiarnpong

Keyword(s):

Silicon Carbide ◽

Rice Husk ◽

Carbothermal Reduction ◽

Nitrogen Atmosphere ◽

Silicon Oxynitride ◽

Reaction Bonding ◽

Silicon Carbide Particle ◽

Silicon Carbide Whisker ◽

Sic Ceramics

Silicon carbide (SiC) ceramics were prepared by carbothermal reduction together with in-situ reaction bonding. Raw rice husk was carbonized in an incineration furnace. The carbonized rice husk was ground and was then treated with hydrochloric acid by varying concentrations. The sample powders were mixed with silicon metal powder and pyrolyzed at various temperatures in either argon or nitrogen atmosphere. Silicon carbide phase was found in all pyrolyzed samples. Cristobalite was found in argon atmosphere pyrolyzed samples while silicon oxynitride was found in the samples pyrolyzed in nitrogen atmosphere at lower than 1500 °C. Silicon carbide whisker is the main phase on the surface of pyrolyzed sample. Increasing pyrolysis temperatures decreased the amount and size of silicon carbide whisker but increased the silicon carbide particle. Porosity and weight loss of samples after pyrolysis were increased with increasing temperatures due to the reaction in the system.

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Biomorphic SiC Prepared from Carbonized Millet by Sol-Gel and Carbothermal Reduction Processing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.152-153.1683 ◽

2010 ◽

Vol 152-153 ◽

pp. 1683-1686

Author(s):

Qing Wang ◽

Ya Hui Zhang

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Silicon Carbide ◽

Phase Composition ◽

Carbothermal Reduction ◽

Sol Gel ◽

X Ray Diffraction ◽

X Ray ◽

Carbon Template ◽

Scanning Electron

Biomorphic silicon carbide (bioSiC) was prepared by high temperature pyrolysis and sol-gel and carbothermal reduction processing at 1600 oC. The morphology and microstructure of carbon-silica composites and purified bioSiC samples were characterized by scanning electron microscopy. The phase composition of the resulting sample was analyzed by X-ray diffraction. The results suggest that the bioSiC mainly consists of cubic ß-SiC, and principally replicates the shape and microstructure of the carbon template.

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Synthesis of Biomorphic Silicon Carbide from Wood

MRS Proceedings ◽

10.1557/proc-1094-dd07-20 ◽

2008 ◽

Vol 1094 ◽

Author(s):

Kwok Cheung Li ◽

Dickon H. L. Ng

Keyword(s):

Silicon Carbide ◽

Carbothermal Reduction ◽

Wood Sample ◽

Sol Gel ◽

Reduction Process ◽

Delonix Regia ◽

Specific Strength ◽

Sic Ceramics ◽

Gel Technique

AbstractWe have successfully produced biomorphic SiC ceramics from silica-infiltrated wood samples of balsa (Ochroma pyramidale) and flame tree (Delonix regia). This conversion of wood sample to a structure of SiC was performed by a sol-gel technique and a carbothermal reduction process. The biomorphic products were confirmed containing β-SiC and their structures were replica of the original structures of the raw wood samples. The biomorphic products from the denser flame tree (C-SiC) had higher specific strength than that from the biomorphic product from balsa (SiC).

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