On a novel refractory high entropy alloy phase evolution: FESEM characterization

Room temperature brittleness and phase instability at elevated temperatures are the mostcritical challenges for applying in refractory high entropy alloys (RHEAs). This researchinvestigates the thermal stability and elements diffusion regime in a novelAlMo۰.۵NbRe۰.۱Ta۰.۵TiZr RHEA. For this purpose, the desired alloy was made in a vacuumarc furnace, and the homogenized alloy was aging treated at ۱۰۰۰°C, ۱۱۰۰°C, and ۱۲۰۰°Cfor ۴۸ hours. A field emission scanning electron microscope (FESEM) was used to checkthe alloy microstructural evolutions. Investigations showed that the alloy comprises a BCCmatrix phase and B۲ basket wave structure. According to the findings, intermetallicparticles were formed in aged samples at temperatures ۱۰۰۰ °C and ۱۱۰۰ °C. Furthermore,the diffusion regimes of elements at different temperatures were investigated, and theseparation behavior of Zr was observed.

Keywords:

Refractory high entropy alloy , Phase stability , Elevated temperature