Das, Probal Kumar and Mukerji, Joydeb (1989) Sintering and properties of silicon nitride densified with liquids in the system MgOAlNSiO2. Journal of the European Ceramic Society, 5 (2). pp. 105-112. ISSN 0955-2219

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Abstract

Silicon nitride was pressureless sintered at 1700–1800°C with liquids in the ternary system MgO-AlN-SiO2; liquids rich in nitrogen and high MgO content sintered readily; Si3N4 of 98% theoretical density was obtained. Heat treatments of the samples were carried out to crystallise the grain boundary phase. Hightemperature flexural strength, fracture toughness and creep of the samples were measured. Increase in nitrogen content with constant MgO:SiO2 ratio produced products with better thermomechanical properties. Superior products were obtained with high nitrogen and low MgO content in the sintering liquid due to a slower sintering rate and acicular grain growth. The best product had a flexural strength (4-point bending test, 40-20 mm) of 490 MPa and fracture toughness of View the MathML source. The creep strain rate and stress of a sample sintered with a liquid with a high MgO content were 1·0 × 10−5 h−1 (at 1200°C) and 100 MPa, respectively.

Item Type:	Article
Subjects:	Engineering Materials
Divisions:	UNSPECIFIED
Depositing User:	Bidhan Chaudhuri
Date Deposited:	06 Dec 2013 08:43
Last Modified:	20 Mar 2016 12:55
URI:	http://cgcri.csircentral.net/id/eprint/2440

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