Evidence for strain and a structural reset in Pd40Ni40P20 bulk metallic glass

Abstract

Individual heat treatments on bulk Pd40Ni40P20 metallic glass samples were performed in a differential scanning calorimeter to either activate mainly β or both α and β relaxation processes as well as heating into the supercooled liquid. The medium-range order of the final amorphous structure was investigated by fluctuation electron microscopy and compared with that of the as-cast state. The results indicate that first, a defined structural reset was achieved by heating into the supercooled liquid. Second, the annealed states exhibit a lower volume fraction of medium-range order, and third, the strain is increased due to the reduction of excess volume after annealing.