Cost effective combustion synthesis of silicon nitride

Journal Article · Tue Jun 03 04:00:00 EDT 2008 · Materials Research Bulletin

DOI:https://doi.org/10.1016/j.materresbull.2007.06.051· OSTI ID:21144030

Yixiang, Chen ^[1]; Jisheng, Du ^[2]

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1. Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)
2. Liaoning Jiayi Metals and Minerals Co. Ltd., Dalian 116001 (China)

The feasibility of mechanical activation (MA)-assisted combustion synthesis (CS) of Si{sub 3}N{sub 4} was demonstrated by using Si/NH{sub 4}Cl as reactants under a nitrogen pressure of 2 MPa. MA treatment significantly enhances the reactivity of Si powders, which effectively promotes the nitridation of silicon. The NH{sub 4}Cl had the same effect as Si{sub 3}N{sub 4} diluent in preventing extensive melting of Si within the combustion wave zone. Full nitridation of Si was achieved at diluent levels as low as 5 wt%. Si{sub 3}N{sub 4} powders with {alpha}-phase contents of up to 90.6 wt% were obtained. The temperature gradient induced by heat release through radiation was responsible for discrepancies in the phase composition and morphologies of the as-synthesized product at different locations.

• OSTI ID: 21144030
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 6 Vol. 43; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AMMONIUM CHLORIDES
CERAMICS
COMBUSTION
COMBUSTION WAVES
MELTING
MICROSTRUCTURE
NITRIDATION
NITROGEN
POWDERS
PRESSURE RANGE MEGA PA 01-10
SILICON
SILICON NITRIDES
SYNTHESIS
X-RAY DIFFRACTION