Abstract
Elastic constants of binary alloys, Ni-Fe and Ni-Cu, of their wide composition ranges having f.c.c. structure, were measured by means of a composite oscillator method in the frequency range from 1 to 5 Mc/s at room temperature. Elastic constants of Ni-Fe alloys vary quadratically as their compositions, while those of Ni-Cu vary linearly. These results can be interpreted in terms of the central and pair-like interactions between atoms of the alloys.