Solubility and partitioning of impurities in Be alloys

TL;DR

This study uses atomic scale simulations to analyze how various impurities and alloying elements interact with beryllium and its intermetallics, revealing their solubility, reactions, and phase formations.

Contribution

It provides detailed insights into impurity accommodation processes in Be alloys, highlighting the effects of Fe, Al, Si, Li, Mg, He, H, C, and O on alloy stability and impurity management.

Findings

Fe can scavenge Al and Si into FeBe5 intermetallics.

Li and Mg are insoluble but reactive with other impurities.

Oxygen strongly interacts with Be, forming BeO.

Abstract

The most energetically favourable accommodation processes for common impurities and alloying elements in Be metal and Be-Fe-Al intermetallics were investigated using atomic scale simulations. Fe additions, combined with suitable heat treatments, may scavange Al and Si through their incorporation into the FeBe5 intermetallic. In the absence of Fe, Al and Si will not be associated with Be metal. Li and Mg are also not soluble, but may react with other impurities if present (such as Al or H). Mg may also form the MgBe13 intermetallic phase under certain conditions. He and H exhibit negligible solubility in all phases investigated and whilst He will tend to form bubbles, H can precipitate as BeH2. Similarly, C additions will form the stable compound Be2C. Finally, oxygen exhibits a strong affinity to Be, exhibiting both some degree of solubility in all phases considered here (though especially metallic Be) and a highly favourable energy of formation for BeO.