ELASTIC SOFTENING IN AMORPHOUS MATERIALS

We present a theory for elastic softening in amorphous materials. Assu ming random orientations of unit cells, we consider the symmetry break ing of degenerate bands due to angle-dependent strains. The angle-aver aged energy splitting between the strain-perturbed levels is obtained, and the elastic constant change is calculated as a function of temper ature. It is shown that the elastic softening in amorphous materials i s qualitatively similar to that in the crystalline case and satisfacto rily explains the experimental data observed for alpha-Fe90Zr10.