Study on the Fabrication of Ceramic Core using a Gel-casting Process in Aqueous medium(I) : Gelation Behavior of Polydispered Ceramic Slip

수용액 매체에서 젤-케스팅 공정을 이용한 세라믹 코어 제조에 관한 연구(I) : 다성분계 분산 세라믹 슬립의 젤화 거동

  • Kim, Jae-Won (Materials Processing Deplrtment, Koreo Institute ofMachinerrand Materials) ;
  • Kim, Du-Hyeon (Materials Processing Deplrtment, Koreo Institute ofMachinerrand Materials) ;
  • Kim, In-Su (Materials Processing Deplrtment, Koreo Institute ofMachinerrand Materials) ;
  • Yu, Yeong-Su (Materials Processing Deplrtment, Koreo Institute ofMachinerrand Materials) ;
  • Kim, Jae-Cheol (Korea Electric power Research Institute) ;
  • Jo, Chang-Yong (Materials Processing Deplrtment, Koreo Institute ofMachinerrand Materials)
  • 김재원 (한국기계연구원 내열재료그룹) ;
  • 김두현 (한국기계연구원 내열재료그룹) ;
  • 김인수 (한국기계연구원 내열재료그룹) ;
  • 유영수 (한국기계연구원 내열재료그룹) ;
  • 김재철 (한전전력연구원 발전연구실) ;
  • 조창용 (한국기계연구원 내열재료그룹)
  • Published : 2001.02.01

Abstract

A new process, gelcasting in aqueous medium, to fabricate complex-shaped ceramic core has investigated. The ceramic slurry, mixture of fused silica powder and additives such as zircon and cordierite, was electrosterically stabilizes. The slip was prepared by ball milling of polydispered ceramic suspension with monomer, dimer and dispersant. The rheological behavior of slip was evaluated by viscosity measurement. It was found that the high solid loading of polydispersed ceramic slip, which has low viscosity of 50vol%, is possible to obtained. The viscosity of the slip was significantly dependent upon the amount of polymer dispersant and the formulation of monomer and dimer. The green bodies were fabricated through casting and gelation at room temperature followed by drying at $25^{\circ}C$ for 48hrs under relative humidity of 80~85%. Crack-free green body was successfully fabricated through the above process.

수용액 매체에서 젤케스팅을 이용하여 복잡한 형상의 세라믹스를 제조하기 위한 새로운 공정을 연구하였다 용융실리카 분말과 첨가제로서 지르콘과 코디어라이트 조성으로 혼합된 현탁액을 electrosteric 방법으로 안정화시켰다. 슬립은 다성분계 세라믹 현탁액에 단량체, 이량체 그러고 분산제를 혼합하고, 볼밀하여 준비하였다. 슬립의 유동학적 특성을 평가하기 위해 점도를 측정하였으며 , 낮은 점도를 갖는 50vo1%의 고농도 다성분계 세라믹 슬립의 제조가 가능하였다. 슬립의 점도는 고분자 분산제의 함량과 단량체 및 이량체의 혼합비에 크게 의존하였다. 성형체는 안정화시킨 슬립을 몰드에 부어 상온에서 젤화시킨 후 $25^{\circ}C$, 80~85% 상대습도 분위기 하에서 48시간동안 건조시켜 제조하였으며 건조된 성형체에는 균열이 발생하지 않았다.

Keywords

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