| 나노 질화규소 세라믹스의 내마모 특성 |
| 김재희, Venkata Manoj Kumar B, 김원식, 홍성현1 |
서울대학교 재료공학부
1신소재공동연구소 (RIAM) |
| Wear Properties of Silicon Nitride Nano-Ceramics |
| Jae-Hee Kim, Venkata Manoj Kumar B, Won-Sik Kim, Seong-Hyeon Hong1 |
Department of Materials Science and Engineering, Seoul National University
1Department of Materials Science and Engineering and Research Institute of Advanced Materials (RIAM) |
|
|
|
|
|
| ABSTRACT |
|
In this study, bulk nano-crystalline $Si_3N_4$ ceramics were fabricated by spark plasma sintering (SPS) and their mechanical properties, in particular wear, were investigated. A wide range of grain sizes, from 80 nm and 250 nm were obtained by varying sintering conditions ($1550^{circ}C$-5 min to $1650^{circ}C$-20 min). The elastic modulus of obtained ceramics was ${sim}250$ GPa and hardness was in the range of $13{sim}14$ GPa. The indentation fracture toughness increased from $2.58MPa{cdot}m^{1/2}$ to $3.24MPa{cdot}m^{1/2}$ with increasing sintering temperature possibly due to the elongated grains. Sliding wear tests revealed at least an order magnitude improvement in wear resistance with grain refinement. Microstructure analysis indicated that nano-$Si_3N_4$ specimens worn mainly through delamination and microcracking, while that of coarser specimens revealed severe wear with grain debonding and fracture. |
| Key words:
Nano-$Si_3N_4$, Spark plasma sintering, Grain size, Wear properties, Mechanical properties |
|
|
|
PDF Links
Full text via DOI
Download Citation 
