Local structure and hardness change of Zr50Cu40Al10 bulk glassy alloy after heavy ion irradiation

Abstract Zr 50 Cu 40 Al 10 bulk glassy alloys before and after 200 MeV Xe ion irradiation with a maximum dose of about 1 × 10 14  ions/cm 2 and 5 MeV Al ion (“self-ion”) irradiation with a dose of about 3 × 10 14  ions/cm 2 have been investigated by positron annihilation and micro-Vickers hardness measurements. No crystallization took place in the samples after the irradiation according to X-ray diffraction measurement. We found that the hardness decreases by irradiation with increasing the irradiation dose. A decreasing trend of positron lifetime, which reflects the size of free volume, was observed. These facts imply that heavy ion irradiation can be used for the local modification of hardness, which is not thermal effect, in Zr 50 Cu 40 Al 10 bulk glassy alloy.