Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Sintering Characterization of Alumina Powders by Hot Pressing after Cold Cyclic Compaction -Densification, Grain-Growth and Fracture Toughness-

상온 반복압축 후 가압소결에 의한 알루미나 분말의 소결특성 -치밀화와 결정립 성장 및 파괴인성-

  • Son, G.S. (Department of Mechanical Engineering, Pohang Institute of Science and Technology) ;
  • Suh, J. (Department of Mechanical Engineering, Pohang Institute of Science and Technology) ;
  • Baik, S.K. (Department of Materials Science and Engineering Pohang Institute of Science and Technology) ;
  • Kim, K.T. (Department of Mechanical Engineering, Pohang Institute of Science and Technology)
  • 손건석 (포항공과대학 기계공학과) ;
  • 서정 (포항공과대학 기계공학과) ;
  • 백성기 (포항공과대학 재료.금속공학과) ;
  • 김기태 (포항공과대학 기계공학과)
  • Published : 1993.01.01
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Abstract

Densification of alumina powder, grain size and fracture toughness of sintered body by hot pressing after cold compaction were investigated and compared to traditional hot pressing process (without cold cyclic compaction). To achieve a higher densification and to reduce the hot pressing time, hot pressing after cold cyclic compaction was more efficient compared to traditional hot pressing. This phenomenon resulted from the increment of packing densityby the acceleration fo rearrangement of powders under cold cyclic compaction. The grain size of sintered body was only dependent on relative density, and densification during hot pressing was governed by thelattice diffusion. Comprisons of grain size, densification mechanism and fracture toughness resulted from hot pressing after/without cold cyclic compaction showed that a low cyclic pressure may not effect on the fragmentation of alumina powders.

Keywords

References

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