ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In order to produce Si3N4/hBN composite with low cost, it seems necessary to use nitridedSi3N4 powders since the cost of Si powder is much cheaper than that of Si3N4 powder. The purpose ofthe present work is to investigate the nitride conditions, and in particular, we focused on therelationship between microstructures and mechanical properties of hot-pressed Si3N4/hBN ceramiccomposite using nitrided Si3N4 powders. The mixed powders of Si3N4 and hBN were prepared bynitriding Si powders at 1380oC for 24 h, and subsequently sintered by hot-pressing at 1800oC for 2 hin N2 atmosphere. The microstructure and mechanical properties of the Si3N4/hBN composites wereinvestigated. Flexural strength, Young’s modulus, and hardness decreased by the addition of 20 vol%hBN. The addition of BN resulted in a decrease in the modulus as well as an increase in the size offracture source, both contribute to the observed decrease in mechanical properties. The Si3N4/BNbased ceramic composites revealed enhanced crack deflection. The Vickers indentation crack pathsin specimens are sinusoidal due to pull-out of grains during crack propagation
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/15/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.544-545.415.pdf
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