Interceram - International Ceramic Review

, Volume 67, Supplement 1, pp 50–57 | Cite as

Preparation of High-Quality Porous Calcium Hexa-Aluminate Ceramics using Salt as Both Reaction Medium and Pore-Former

  • Xueyin LiuEmail author
  • Yan-gai Liu
  • Zhaohui Huang
  • Minghao Fang
Research and Development Porous Ceramics


Porous calcium hexa-aluminate (CA6) ceramics were synthesized by a molten salt-mediated technique using CaCO3 and α-Al2O3 powders as the main raw materials. The effects of salt type and content, along with firing temperature on phase formation, microstructural evolution, pore generation and size distribution, and mechanical strength of fired samples were investigated and compared. Among the three tested salts (KCl, NaCl, and CaCl2), KCl showed the best whereas CaCl2 showed the worst accelerating effect on CA6 formation. In the case of the former, phase-pure CA6 was formed after 3 h at 1500 °C, whereas in the case of the latter, CA2 was formed instead as a main phase. The salt not only acted as a reaction medium, accelerating CA6 formation, but also acted as a pore former, creating high levels of porosity in the fired samples. The apparent porosity of the fired samples clearly increased with an increase in KCl content. But the majority of pores were still micron sized and the pore size distribution was relatively narrow. This, along with the possible toughening effect from the well-developed plate-like CA6, conferred relatively high mechanical strength on the final highly porous CA6 ceramics.


calcium hexa-aluminate porous ceramics molten salt pore size distribution 



This work was financially supported by the National Natural Science Foundation of China (Grant no. 51032007), the Fundamental Research Funds for the Central Universities (Grant no. 2012067), and the Doctoral Scientific Research Foundation of Quzhou University (Grant no. BSYJ201707).


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Copyright information

© Springer Fachmedien Wiesbaden GmbH, part of Springer Nature 2018

Authors and Affiliations

  • Xueyin Liu
    • 1
    Email author
  • Yan-gai Liu
    • 2
  • Zhaohui Huang
    • 2
  • Minghao Fang
    • 2
  1. 1.College of Civil Engineering and ArchitectureQuzhou UniversityQuzhou, ZhejiangChina
  2. 2.School of Materials Science and Technology, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral MaterialsChina University of GeosciencesBeijingChina

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