• Title/Summary/Keyword: Electrosteric stabilization

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Dispersion and Forming of Alumina Powders via Crosslinkable Organic Molecules (가교가능한 유기화합물을 이용한 알루미나의 분산과 성형)

  • 김봉호;신평우;백운규;정연길;최성철;박철원
    • Journal of the Korean Ceramic Society
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    • v.32 no.2
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    • pp.217-226
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    • 1995
  • Alumina powders were dispersed using crosslinkable organic molecules by electrosteric stabilization and then consolidated by crosslinking of organic molecules. The effect of processing variables such as the physicochemical properties of both solvent media and organic molecules, the proportions of mixed organic media, etc. were studied. FT-IR was used todeduce the mechanism of organic molecules adsorption on the alumina particle surfaces. The adsorption characteristics and the electrokinetic behavior of alumina suspensions were correlated with the stability of particle in alumina suspension using rheological measurements. The green body of alumina consolidated by the chemical crosslinking of the adsorbed organic molecules after the alumina suspension had been stabilized was tough enough for green machining and the sintered alumina fabricated by this proposed process also showed a high bending strength and a homogeneous microstructure.

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Rheological control to develop a self-consolidating ECC (자기충전용 ECC를 개발하기 위한 레올로지 특성에 관한 실험)

  • Kim, Jeong-Su;Lee, Jong-Han;Kim, Yun-Yong;Kim, Jin-Keun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.539-540
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    • 2009
  • A self-consolidating engineered cementitious composite (ECC), which exhibits tensile strain-hardening behavior in the hardened state, while maintaining self-consolidating properties in the fresh state, has been developed by employing electrosteric dispersion and stabilization.

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Fabrication of Complex-shaped mullite Ceamics by Gelcasting (Gelcasting을 이용한 Mullite 세라믹스의 제조)

  • 최연규
    • Journal of the Korean Ceramic Society
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    • v.36 no.7
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    • pp.773-781
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    • 1999
  • 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.

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