| 학회 |
한국재료학회 |
| 학술대회 |
2021년 봄 (05/12 ~ 05/14, 광주 김대중컨벤션센터) |
| 권호 |
27권 1호 |
| 발표분야 |
D. 구조 재료 분과 |
| 제목 |
Pressureless Sintered Silicon Nitride Ceramics with Controlling α-β Ratio for Self-reinforcement |
| 초록 |
Increasing demands for electronic devices has revealed the importance of a structural material based on its high performance. Silicon nitride ceramics which possess higher strength but lower thermal conductivity than aluminum nitride are generally sintered via gas pressure sintering to maximize those properties. The gas pressure sintering is considered the Si3N4 industry standard; however, the pressureless sintering offers a promising alternative with the added benefit of versatility. In this study, a self-reinforced Si3N4 ceramic with high thermal conductivity was prepared through multi-step pressureless sintering with Y2O3 and MgO additives. The steps consisted of phase control and densification stages to provide additional crystallization sites using a partial α-β phase transformation, which also established a bimodal microstructure. The optimal temperature for the intermediate stage that exhibited the maximum flexural strength was determined by comparing the phase content and linear shrinkage. After final sintering, a flexural strength of 932 MPa and a thermal conductivity of 74 W/mK were achieved, which are 11.5% and 8.0% higher, respectively, than those obtained using conventional pressureless sintering. |
| 저자 |
Jung Hoon Kong, Ho Jin Ma, Wook Ki Jung, Do Kyung Kim
|
| 소속 |
KAIST |
| 키워드 |
<P>Si3N4; pressureless sintering; strength; thermal conductivity</P>
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| E-Mail |
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