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Journal of the Korean Ceramic Society 1999;36(7): 773. |
Gelcasting을 이용한 Mullite 세라믹스의 제조 |
최연규 |
한국과학기술원 재료계면공학연구센터 |
Fabrication of Complex-shaped mullite Ceamics by Gelcasting |
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ABSTRACT |
A new technique to fabricate complex-shaped mullite has been developed through gelcasting without organic binder. The suspension of a commercial mullite powder and boehmite-SiO2 sol as binder was elecrtrosterically stabilized. Ammonium polymetharylyate was employed as a dispersant for the electrosteric stabilization. Complex-shaped bodies were made through casting and gelation at room temperature. The green bodies were dried at a temperature of 30$^{circ}C$ and relative humidity of 98% without crack development. The dried bodies were then pressureless-sintered at 1650$^{circ}C$ for 2 h to get a relative density of 98% The Vickers hardness and 4-point flexural strength of sintered parts were 11.0 GPa and 150MPa respectively which are similar to those of commercially available sintered mullite. |
Key words:
Sol-Gel, stabilization, Dispersion, Viscosity, Mullite, Gelecasting |
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