Calculation of the shear modulus properties of amorphous-alloys

Abstract

An analytical expression for the shear modulus G of an amorphous metal is derived as a function of a few interatomic potential parameters and the dispersion for the nearest neighbour distance. The experimentally observed relative difference between the amorphous and crystalline shear modulus is reproduced in a quantitative way. It is shown that the anharmonic contribution in the potential plays a crucial role in the explanation for the small G value of an amorphous alloy in comparison with the value for a crystal with the same chemical composition. By differentiation of the expression for G, a number of correlations are derived between the changes of different physical properties during irreversible annealing of an amorphous alloy. These correlations are confirmed in a semi-quantitative way by experiment.