A high stability B2-containing refractory multi-principal element alloy

An equiatomic HfNbTaRuZr refractory multi-principal alloy was cast via arc melting and characterized in both as-cast vacuum annealed conditions. (Nb, Ta)-rich body-centered cubic (BCC), (Hf, Ru)-rich B2, Zr)-rich hexagonal close-packed (HCP) phases materials were identified by x-ray diffraction transmission electron microscopy, with all stable from 1350 to 1575 °C. At °C the contained 35.9 % of a morphologically B2 phase. Preferential segregation oxygen nitrogen HCP phase observed. The volume fractions increased decreased, respectively, increasing annealing temperature. Lamellar microstructures present along grain boundaries determined result discontinuous transformation disordered BCC BCC. Refinement size microstructure achieved splat quenching, resulting exceptional hardness due nano-scale precipitates.