Changes in Mass Density and Sound Velocity of Amorphous Pd 80 Si 20 by Low Temperature Ion Irradiation

Changes in transverse phonon sound velocity were measured during low temperature irradiation of amorphous Pd 80 Si 20 with 3.5 MeV krypton ions. The sound velocity decreases as a function of the ion fluence and shows a tendency to saturate at large fluences at a relative change of -4.7%. The changes in sound velocity were used to determine the changes in shear elastic constant and in Debye temperature both of which were in reasonable agreement with the value reported in the literature.