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:
Two kinds of ultra high temperature ceramics (UHTC), ZrB2-20Vol.%SiC and ZrB2-15Vol.%SiC-5Vol.% SiCn (nano-size) were prepared by spark plasma sintering (SPS). The residual strength wasused to characterize thermal shock resistance of ZrB2-SiC ceramics by quenching tests in the water. Themechanism of thermal shock damage of the ceramics was examined by SEM analysis. The results showedthat the formed glassy phase has significant effect on thermal shock resistance of ZrB2-SiC ceramics.When the thermal shock temperature rises, the residual strength of ZrB2-SiC ceramics after thermal shockwill decrease gradually. The formed glassy phase when quenched from the temperature of 1400°C canrepair or heal the cracks and induce the higher residual strength. However, when the temperatureincreases to 1600°C, the residual strength of ZrB2-SiC ceramics decreases significantly due to thevolatilization of the glassy phase. The residual strength of ZrB2-15Vol.% SiC-5Vol.% SiCn ceramic ishigher than that of ZrB2-20Vol.%SiC ceramic, because nano SiC is easy to be oxidized and to induce theformation of more glassy phases and to improve the thermal shock resistance of the sample
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/56/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.368-372.1727.pdf
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