Pressure-induced phase transitions in HoDyYGdTb high-entropy alloy

Abstract The HoDyYGdTb high-entropy alloy (HEA) was synthesized and its structural phase transitions were determined under compression up to 60.1 GPa at room temperature. Three transformations following the sequence hexagonal close-packed (hcp) → samarium type (Sm-type) → double hexagonal close-packed (dhcp) → distorted face-center cubic (dfcc) are observed at 4.4, 26.7, and 40.2 GPa, respectively. The high pressure equation of state was determined for the HEA according to third-order Birch-Murnaghan equation of state. The results show that the bulk modulus and atomic volume of the alloy obey the “additivity law”.