Phase stability of novel HfNbTaTiVZr refractory high entropy alloy under ion irradiation

HfNbTaTiVZr refractory high entropy alloy (RHEA) fabricated by arc melting shows the single-phase body centered cubic (BCC) structure. Radiation-induced amorphization (RIA) is observed at 2 displacements per atom (dpa) at 298 K while the specimen remains its crystal structure at 423 K. The critical amorphization temperature (T-c) is likely within 298-423 K. RIA is mainly attributed to the accumulation of Frenkel pairs caused by elastic collisions under ion irradiation and the large atomic size mismatch in the studied RHEA facilitates the amorphization process. RIA of RHEA is for the first time reported and the finding challenges the current understanding of phase stability of RHEAs upon irradiation.

Automated summary

The HfNbTaTiVZr refractory high entropy alloy fabricated by arc melting exhibits single-phase body centered cubic structure. Radiation-induced amorphization is observed at 2 displacements per atom at 298 K, with the specimen maintaining its crystal structure at 423 K. The large atomic size mismatch in the studied RHEA facilitates the amorphization process, challenging the current understanding of phase stability of RHEAs upon irradiation.