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Densification and sintering dynamics of 10NiO-NiFe2O4 composites doped with CaO

  • Li Jie  (李劼)
  • Zhang Gang  (张刚)Email author
  • Lai Yan-qing  (赖延清)
  • Zhang Yong  (张勇)
  • Tian Zhong-liang  (田忠良)
Article

Abstract

The effects of CaO content in the range from 0 to 4.0%, and sintering temperature on the phase composition, relative density and electrical conductivity of 10NiO-NiFe2O4 composites doped with CaO were studied. The results show that there is no change of structure for NiO or NiFe2O4; there is apparent oxygen absorbing and releasing behavior during the heating process in air for 10NiO-NiFe2O4 composites. Introduction of CaO can accelerate the densification of 10NiO-NiFe2O4 composites. The maximum value of relative density is 98.75% for composite doped with 2.0% CaO and sintered at 1 200 °C, which is beyond about 20% for the undoped composites. The sintering activated energy of sample containing 2% CaO decreases by 15.87 kJ/mol, compared with that of the undoped sample.

Key words

aluminum electrolysis inert anode CaO doping densification sintering dynamics 

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Copyright information

© Central South University Press, Sole distributor outside Mainland China: Springer 2007

Authors and Affiliations

  • Li Jie  (李劼)
    • 1
  • Zhang Gang  (张刚)
    • 1
    Email author
  • Lai Yan-qing  (赖延清)
    • 1
  • Zhang Yong  (张勇)
    • 1
  • Tian Zhong-liang  (田忠良)
    • 1
  1. 1.School of Metallurgical Science and EngineeringCentral South UniversityChangshaChina

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