会议专题

Effect of Glass Phase on the Thermal Shock Resistance of ZrB2-SiC Ultra High Temperature Ceramic

  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 was used to characterize thermal shock resistance of ZrB2-SiC ceramics by quenching tests in the water.The mechanism of thermal shock damage of the ceramics was examined by SEM analysis.The results showed that 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 shock will decrease gradually.The formed glassy phase when quenched from the temperature of 1400℃ can repair or heal the cracks and induce the higher residual strength.However,when the temperature increases to 1600℃,the residual strength of ZrB2-SiC ceramics decreases significantly due to the volatilization of the glassy phase.The residual strength of ZrB2-15Vol.% SiC-5Vol.% SiCn ceramic is higher than that of ZrB2-20Vol.%SiC ceramic,because nano SiC is easy to be oxidized and to induce the formation of more glassy phases and to improve the thermal shock resistance of the sample.

Ultra high temperature ceramics Thermal shock resistance Glassy phase

Zhu Shizhen Xu Qiang Fens Chao Zhao Junfeng Cao Jianling Wang Fuchi

School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China

国际会议

The Fifth China International Conference on High-Performance Ceramics (第五届先进陶瓷国际研讨会(CICC-5))

长沙

英文

1727-1729

2007-05-10(万方平台首次上网日期,不代表论文的发表时间)