Effect of Impurities on Formation of Pores in Porous Alumina during Unidirectional Solidification

Abstract:

A porous alumina with cylindrical pores was fabricated by unidirectional solidification under hydrogen gas flow (0.1 MPa) using alumina feed rods doped with silica, calcia or sodium oxide. The additives in the feed rods strongly affect the formation of porous structure during the solidification. The porosity increases with increasing silica content. The increase of porosity is enhanced by further addition of sodium oxide. The addition of calcia to the feed rod is effective on the homogenization of pore distribution. The porous alumina with 1mol%CaO and 20mol%SiO2 additives showed 50% porosity and homogeneous pores distribution.

• Periodical: Materials Science Forum (Volume 569)
• Pages: 313-316
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.569.313
• Online since: January 2008
• Authors: Shunkichi Ueno, Li Ming Lin, Hideo Nakajima
• Keywords: Glassy Boundary Phase, Impurity, Porous Alumina, Unidirectional Solidification

References

[1] K. Ishizaki, S. Komarneni and M. Nanko, in: Porous Materials: Process Technology and Applications, (Materials Technology Series, Kluwer Academic Publishers, 1998).

DOI: 10.1007/978-1-4615-5811-8_5

[2] T. Isobe, T. Tomita, Y. Kameshima, A. Nakajima and K. Okada: J. Europ. Ceram. Soc. Vol. 26 (2006), 957-960.

[3] G.J. Zhang, J.F. Yang, and T. Ohji: J. Am. Ceram. Soc. Vol. 84 (2001), 1395-97.

[4] T. Fukasawa, Z.Y. Deng, M. Ando and T. Ohji: J. Ceram. Soc. Jpn. Vol. 109 (2001), 1035-1038.

[5] S. Ueno, L.M. Lin and H. Nakajima: J. Am. Ceram. Soc., in press.

[6] S. Ueno, L.M. Lin, S.K. Hyun and H. Nakajima: Mater. Trans. Vol. 47 (2006), 2167-71.

[7] S. Ueno, L.M. Lin and H. Nakajima: submitted to Journal of the Ceramics Society of Jpn.