Thermal shock behavior of SiC-whisker-reinforced diboride ultrahigh-temperature ceramics

ZrB2-SiCw ultrahigh-temperature ceramics have been investigated by water quench testing over the temperature range 400-1200 degrees C. All specimens preserved integrity and retained most of their strength (more than 80%) after being shocked for one or five cycles. Obvious surface changes as a result of oxidation were observed when testing at temperatures higher than 800 degrees C. Surface oxidation plays an important role in the thermal shock behavior of SiC-whisker-reinforced diboride ultrahigh-temperature ceramics. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.