Phase Evolution and Synthesis of Be₁₂ Nb Intermetallic Compound in the 800-1300 °C Temperature Range

Beryllium-based intermetallic compounds, such as Be₁₂Nb, are attracting growing interest for their high thermal stability and potential to replace pure beryllium as neutron reflectors and multipliers in both fission and future fusion reactors, with additional applications in metallurgy, aerospace, and hydrogen technology. The paper presents the results of an investigation of the thermal treatment and phase formation of the intermetallic compound Be₁₂Nb from a mixture of niobium and beryllium powders in the temperature range of 800-1300 °C. The phase evolution was assessed as a function of sintering temperature and time. A nearly single-phase Be₁₂Nb composition was achieved at 1100 °C, while decomposition into lower-order beryllides such as Be₁₇Nb₂ occurred at temperatures ≥1200 °C, indicating thermal instability of Be₁₂Nb under vacuum. Careful handling of sintering in low vacuum minimized oxidation, though signs of possible BeO formation were noted. The findings complement and extend earlier reports on Be₁₂Nb synthesis via plasma sintering, mechanical alloying, and other powder metallurgy routes, providing broader insight into phase formation and synthesis. These results provide a foundation for optimizing the manufacturing parameters required to produce homogeneous Be₁₂Nb-based components and billets at an industrial scale. Additionally, they help define the operational temperature limits necessary to preserve the material's phase integrity during application.