Abstract
This paper examines the catalytic effects offlourides on the ϒ→α-Al2O3 phase transformation by heat treating commercial alumina samples with 2wt% additions of different flouride compounds. The various additives were ranked according to their effect on transformation temperature. Experiments were conducted to explain the high temperature coherence of crusts. The findings indicate that an alumina network is formed during ϒ→α phase transformation, which reinforces the crust on top of the cryolite bath.
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Additional information
R. Oedegard, S. Roenning, S. Rolseth and J. Thonstad are currently involved with work at the Laboratories of Industrial Electrochemistry and SINTEF, The Foundation for Scientific and Industrial Research at the Norwegian Institute of Technology in Norway.
Editor’s Note: This paper was adapted from a presentation at the Light Metals 1985 programming in New York City.
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Oedegard, R., Roenning, S., Rolseth, S. et al. Crust Formation in Aluminum Cells. JOM 37, 25–28 (1985). https://doi.org/10.1007/BF03258735
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DOI: https://doi.org/10.1007/BF03258735