Low-Temperature Synthesis of MgAl2O4 by Capsule HIP Using Hydroxides as Starting Materials

Kensuke Yanagida; Yuki Yamaguchi; Kenjiro Fujimoto; Shigeru Ito

doi:10.4028/www.scientific.net/KEM.617.217

Paper Titles

Evaluation of Iodine-Adsorption on Magnesium Compounds Toward Fixing of Radioactive Iodine
p.201

Fabrication and Fracture Toughness of CNTs/Alumina Composites with Fine Microstructures
p.205

Influence of Cu₂O Addition on Crystallization Process and Microstructure of Transparent Mica Glass-Ceramics
p.209

Interface Formation of Unidirectional SiC_f/SiC Composites by Electrophoretic Deposition Method
p.213

Low-Temperature Synthesis of MgAl₂O₄ by Capsule HIP Using Hydroxides as Starting Materials
p.217

Morphological Control of Magnesium Phosphate Hydrate from a Highly Concentrated Alkaline Earth Metal Phosphate Solution by Microwave Heating
p.221

Reactivity of Carbonates in Superheated Steam under Atmospheric Pressure
p.225

Synthesis of Bio-Cation-Substituted Ca-Apatites by Precipitation
p.229

Transition Edge Sensor (TES) X-Ray Detecting System with Sensitivity Correction to Stabilize the Spectrum Peak Center
p.233

HomeKey Engineering MaterialsKey Engineering Materials Vol. 617Low-Temperature Synthesis of MgAl2O4 by Capsule...

Low-Temperature Synthesis of MgAl₂O₄ by Capsule HIP Using Hydroxides as Starting Materials

Abstract:

Low-temperature synthesis of spinel (MgAl₂O₄) was investigated by capsule hot isostatic press (HIP) using hydroxides as starting materials; Mg(OH)₂, MgO, Al(OH)₃, g-AlOOH, g-Al₂O₃. MgAl₂O₄ has been conventionally prepared above 1400 °C, whereas the mixtures containing the hydroxides reacted at 400-500 °C for 1 h under 200 MPa of isostatic pressure to form MgAl₂O₄. The hydroxides showed high reactivity to form MgAl₂O₄ with high crystallinity. However, the products more or less contained Mg(OH)₂. The single phase of MgAl₂O₄ was obtained by adding 20 mass% of water to the starting mixtures of Mg(OH)₂ - Al(OH)₃, Mg(OH)₂ - g-Al₂O₃ and MgO - Al(OH)₃. The average grain size of the MgAl₂O₄ was 70 – 100 nm. It was concluded that the transformation of AlOOH or g-Al₂O₃ was promoted by a small amount of water and that Mg(OH)₂ rapidly reacted with the active intermediate compound between AlOOH or g-Al₂O₃ and a-Al₂O₃.

You might also be interested in these eBooks

View Preview

Info:

Periodical:

Key Engineering Materials (Volume 617)

Pages:

217-220

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.617.217

Citation:

Cite this paper

Online since:

June 2014

Authors:

Kensuke Yanagida*, Yuki Yamaguchi, Kenjiro Fujimoto, Shigeru Ito

Keywords:

HIP, Hydroxide, Low-Temperature Synthesis, MgAl₂O₄, Spinel

Export:

RIS, BibTeX

Price:

Permissions CCC:

Request Permissions

Permissions PLS:

Request Permissions

Сopyright:

Citation:

* - Corresponding Author

References

[1] R. Sarkar, G. Bannerjee, R.A. Lupton, Effect of Addition of TiO2 on Reaction Sintered MgO-Al2O3 Spinels, J. Eur. Ceram. Soc. 20 (2000) 2133-2141.

DOI: 10.1016/s0955-2219(00)00097-2

Google Scholar

[2] M.M. Rashad, Z.I. Zaki and H. El-Shall, A Novel Approach for Synthesis of Nanocrystalline MgAl2O4 Powders by Co-precipitation Method, J. Mater Sci. 44 (2009) 2992-2998.

DOI: 10.1007/s10853-009-3397-8

Google Scholar

[3] G. Ye, G. Oprea and T. Troczynski, Synthesis of MgAl2O4 Spinel Powder by Combination of sol–gel and Precipitation Processes, J. Am. Ceram. Soc. 88 (2005) 3241-3244.

DOI: 10.1111/j.1551-2916.2005.00564.x

Google Scholar

[4] S. Ito, N. Umehara, H. Takata and T. Fujii, Phase Transition of g-Al2O3 Under Hot Isostatic Pressure, Sol. St. Ion. 172 (2004) 403-406.

DOI: 10.1016/j.ssi.2004.03.024

Google Scholar

[5] S. Ito, D. Sato and K. Fujimoto, Effect of Moisture on the Solid State Reactions in Capsule HIP, Proc. (2005) 131-136.

Google Scholar

[6] P.J. James, Isoststic Pressing Technology Applied Science Publishers, New York, (1983).

Google Scholar

[7] P.D. Garn and T.S. Habash, J. Phys. Chem., 83 (1979) 229.

Google Scholar