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ã507-0071 å²éçå€æ²»èŠåžæã¶äž 10-6-29
Forming and Application of Porous Ceramics by Gelcasting
Hiroaki Takegami, Masayoshi Fuji and Minoru Takahashi
Ceramics Research Laboratory, Nagoya Institute of Technology, 10-6-29, Asahigaoka, Tajimi 507-0071, Japan
The fabrication of complex-shaped ceramic parts in large quantities has been limited to the conventional ceramic conventional forming processes, such as injection molding, slip casting. Gelcasting is a novel forming method for making complex-shaped ceramic bodies. In this process, a ceramic powder slurry is prepared with a water-based monomer solution and then polymerized in situ after casting into a mold, producing a macromolecular network to hold the ceramic particles. The dried body in the presence of a cross-linked polymer network is rather strong and can be machined so as to obtain more complex shaped products. Porous ceramics, which have high potential for applications related to the environmental and energetic, are also fabricated by gelcasting. Foams can be produced by mechanical frothing in an N2 controlling system. The incorporation of porosity in ceramic microstructures with tailored pore size and its attribute controlled in many possible ways. In this paper, a principle of gelcasting process and applications of porous ceramics fabricated by gelcasting are introduced.
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Fig. 1 General gelcasting process flowchart
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Fig. 4 Double layered porous alumina (Ï70mm, d
20mm) produced via the different routes, where the development of the pores was controlled by changes of (A) the surfactants, (B) the gelation agents, and (C) the slurry temperature
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ãã«æ°ããæè¡ãžãšçºå±ããŠããããšãæåŸ ããã åèæç® 1) O. O. Omatete, M. A. Janney, R. A. Strehlow:
Gelcasting - a new ceramic forming process, Am. Ceram. Soc. Bull. 70(10) (1991) 1641-1649
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3) S.D. Nunn, O.O. Omatete, C.A. WallsD.L. Barker:
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