Structure related potential-upsurge during tensile creep of high entropy Al20Ce20La20Ni20Y20 metallic glass

Abstract In this paper, the dramatical increase in the apparent activation energy (defined as potential-upsurge) of tensile creep of a high entropy Al20Ce20La20Ni20Y20 metallic glass was discovered. The temperature referring to the occurrence of potential upsurge is around the onset relaxation temperature of as-spun specimen (110 °C (383 K)) measured by differential scanning calorimetry. Below 110 °C, the value of apparent activation energy is determined to be 3.9 kJ/mol, nevertheless, this value dramatically increases to 35.4 kJ/mol above 110 °C. Kelvin model was utilized to resolve the creep mechanism. The short-time relaxation behavior indicates a dramatical increase above 110 °C. The work reveals that the extension and retardation of smaller defects are responsible for the potential-upsurge in the apparent activation energy of tensile creep.