Effect of Additives and Cooling Rates on the Electrical Resistivity of BaTiO3 Ceramics (I)

BaTiO$_3$ 세라믹스의 전기저항에 미치는 첨가제와 냉각속도의 영향(I) - TiO$_2$, SiO$_2$ 및 Al2O$_3$ 단미첨가 -

  • 염희남 (명지대학교 무기재료공학과) ;
  • 하명수 (명지대학교 무기재료공학과) ;
  • 이재춘 (명지대학교 무기재료공학과) ;
  • 정윤중 (명지대학교 무기재료공학과)
  • Published : 1991.09.01

Abstract

Microstructure, room temperature resistivity and temperature coefficient of resistance of BaTiO3 ceramics were studied by varying cooling rates and additives such as TiO2, SiO2 and Al2O3. The basic composition of the BaTiO3 ceramics was formed by adding 0.25 mol% Dy2O3 and 0.07 mol% MnO2 to the BaTiO3 composition. Unlike the additives of SiO2 and Al2O3, an addition of 2 mol% TiO2 to the basic composition was effective to control the grain size of the fired specimens. The room temperature resistivity and the temperature coefficient of resistance for the specimen of this particular compostion were measured as about 102 ohm.cm and 16.5%/$^{\circ}C$, respectively. The observed grain boundary phase of the sample with Al2O3 additive was BaTi3O7, while that of the samples with SiO2 additive was confirmed as BaTiSiO5.

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References

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