Abstract
The commercial preparation of aluminum-diboride flakes in aluminum relies on relatively expensive starting materials. A new synthesis has been developed that allows AlB2 to be prepared directly from the reaction of borax (Na2B4O7·10H2O) or boron oxide (B2O3) with aluminum. Aluminum metal at temperatures higher than 900°C has been shown to reduce these boron-containing compounds, producing an Al2O3-containing slag and AlB2. A natural separation occurs, leaving AlB2 in the molten aluminum and Al2O3 as part of a slag that forms at the melt surface. Samples containing up to 10 vol.% AlB2 in an aluminum matrix have been directly prepared using this method.
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For more information, contact A.C. Hall, Sandia National Labs., P.O. Box 5800, Mail Stop 0340, Albuquerque, New Mexico 87185; (505) 284-6964; fax (505) 845-9659.
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Hall, A.C., Economy, J. Preparing high- and low-aspect ratio AlB2 flakes from borax or boron oxide. JOM 52, 42–44 (2000). https://doi.org/10.1007/s11837-000-0046-8
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DOI: https://doi.org/10.1007/s11837-000-0046-8