|
|
|
Journal of the Korean Ceramic Society 1989;26(3): 402. |
| 한국산 천연원료로부터 $beta$-Sialon의 합성 및 그 특성 |
| 임헌진, 이홍림 |
| 연세대학교 공과대학 요업공학과 |
| Properties of $beta$-Sialon Prepared from Korean Natural Resources |
|
|
|
|
|
|
|
| ABSTRACT |
|
$beta$-Sialon powder was synthesized by the simultaneous reduction and nitridation of the mixed powder of Hadong kaolin and Kimcheon quartzite, using graphite as a reducing agent. The synthesized $beta$-Sialon powder (Z=1) was hot-pressed at 175$0^{circ}C$, for 90min under 30MPa in N2 atmosphere, after Yttria and YAG composition material were added as sintering agents. The effects of grain-boundary crystallization on high-temperature mechanical properties of $beta$-Sialon ceramics were investigated. Strength degradation was observed at above 1,00$0^{circ}C$ for the $beta$-Sialon (Z=1)-8wt% Y2O3 composition, but it was not observed up to 1,20$0^{circ}C$ for the $beta$-Sialon-8wt% YAG composition which was annealed at 1,40$0^{circ}C$ for 4 hours in N2 atmosphere. After the $beta$-Sialon-8wt% YAG composition was annealed, the decrease of fracture toughness was observed. |
|
|
|
PDF Links
Full text via DOI 
Download Citation 
