ISSN:
1013-9826
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:
There has been a great progress in the development of heat-resistant silicon carbide ceramics,owing to the better understanding of composition-microstructure-properties relations. Based on theprogress, it has been possible to fabricate heat-resistant SiC ceramics with improved fracture toughness.In this paper, three rare-earth oxides (Re2O3, Re=Er, Lu, and Sc) in combination with AlN were used assintering additives for a β-SiC containing 1 vol% α-SiC seeds. The effect of intergranular phase, usingRe2O3 and AlN as sintering additives, on the microstructure and mechanical properties of liquid-phasesintered,and subsequently annealed SiC ceramics were investigated. The microstructure and mechanicalproperties were strongly influenced by the sintering additive composition, which determines the chemistryand structure of IGP. The strength and fracture toughness of the Lu2O3-doped SiC were ∼700 MPa at1400oC and ∼6 MPa.m1/2 at room temperature, respectively. The beneficial effect of the new additivecompositions on high-temperature strength was attributed to the crystallization of the intergranular phase
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/53/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.336-338.1409.pdf
