Comparative study on arc-melted and plasma-sintered beryllides

Highlights: ► We report a comparative study of arc-melted and plasma-sintered beryllides. ► The effects of Ti amount in each beryllide were investigated by measuring density, hardness, microstructure. ► Plasma-sintered beryllide shows superior mechanical property over arc-melted one. ► Be–7 at.% Ti plasma-sintered beryllide can be homogenized into Be12Ti phase. - Abstract: This study compares arc-melted and plasma-sintered beryllides, beryllium intermetallic compounds, investigating the effects of density, hardness, microstructure, and annealing on stability. From the electron probe micro-analyzer and X-ray diffraction analysis results, it was obvious that the plasma-sintered samples, including those with 3 and 5 at.% Ti, were composed of α-Be and Be12Ti phases, while Be17Ti2 and Be2Ti phases were additionally observed for the Be–7 at.% Ti sample. In case of the arc-melted beryllides, it consisted of α-Be and Be12Ti in the 3 at.% Ti and 5 at.% Ti samples, whereas the Be12Ti phase surrounded Be10Ti as a peritectic phase for Be–7 at.% Ti. Density and hardness measurements confirmed that the plasma-sintered beryllides were sintered with higher density and hardness than the arc-melted beryllides. It is suggested that the higher sinterability and greater amount of Be12Ti phase resulted in increased density and hardness, respectively. In addition, the annealing treatment at 1473 K for 5 h was carried out to investigate the homogenization of the compositional structure. From the results of observation analysis for the specimens denoted as Be–3 at.% Ti and Be–5 at.% fabricated by both methods, there was no change on compositional structure. However, for arc-melted Be–7 at.% Ti, the Be phase was almost diminished, whereas there was a slight increase in the Be12Ti phase and a slight decrease in the Be10Ti phase. In the case of the plasma-sintered Be–7 at.% Ti specimen, it was clarified that the Be17Ti2 and Be2Ti phases were homogenized into the Be12Ti phase.