We are interested in the possibility of using induction melting in order to recycle beryllium components. This process will require the use of a container for the molten Be. Although BeO is the obvious choice of materials based on compatibility, engineering considerations dictated that other materials be considered. Therefore, a series of experiments was performed in order to test the compatibility of molten beryllium with various ceramic crucible materials. The materials tested include Al2O3, Y2O3, MgO, ZrO2, SiC and SiO2 (fused silica). Alumina exhibited the best compatibility among the materials tested, based on the relatively trivial observation that the molten beryllium did not stick to alumina. We have evaluated the reaction products and to some extent the mechanism of reaction of beryllium with each of these materials. In the case of alumina for example, the compatibility may be attributed to the formation of a layer of an intermediate BeO-Al2O3 phase or phases. In the magnesia, yttria, and zirconia Be systems ternary oxides are not observed but the oxides may be reduced by beryllium resulting in formation of intermetallic phases and beryllium oxide. The silicon based compounds are reduced to form BeO and free silicon. The significance of these results with regard to the published thermodynamic data (particularly phase diagrams) will be discussed. Additional tests were conducted to evaluate the products of the reaction between molten beryllium and stainless steel. This report also discusses the results of these tests.
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