Transmission Electron Microscopy Investigation of Hot-pressed ZrB2-SiC with B4C Additive

Kim, Seongwon;Chae, Jung-Min;Lee, Sung-Min;Oh, Yoon-Suk;Kim, Hyung-Tae;Jang, Byung-Koog

  • Received : 2015.09.09
  • Accepted : 2015.10.16
  • Published : 2015.11.30


This paper reports the microstructure of hot-pressed $ZrB_2$-SiC ceramics with added $B_4C$ as characterized by transmission electron microscopy. $ZrB_2$ has a melting point of $3245^{\circ}C$, a relatively low density of $6.1g/cm^3$, and specific mechanical properties at an elevated temperature, making it a candidate for application to environments with ultra-high temperatures which exceed $2000^{\circ}C$. Due to the non-sinterability of $ZrB_2$-based ceramics, research on sintering aids such as $B_4C$ or $MoSi_2$ has become prominent recently. From TEM investigations, an amorphous layer with contaminant oxide is observed in the vicinity of $B_4C$ grains remaining in hot-pressed $ZrB_2$-SiC ceramics with $B_4C$ as an additive. The effect of a $B_4C$ addition on the microstructure of this system is also discussed.


Ultra-high-temperature ceramics (UHTCs);$ZrB_2$-SiC;$B_4C$ addition;Densification


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Supported by : Korea Institute of Ceramic Engineering and Technology