Concentration dependence of partial vibrational spectra in Ni–Nb and Cu–Zr metallic glasses

Abstract

The neutron inelastic scattering of the Ni44Nb56 and Cu33Zr67 metallic glasses with isotope substitution for Cu and Ni were measured. The results are compared to earlier data for Ni62Nb38 and Cu64Zr36 (Ni and Cu isotopic substitution). Availability of two samples with different isotope content for each system has enabled partial vibrational densities of states to be obtained for both materials. The ratios of average force constants, BNi/BNb and BCu/BZr, and mean-square atomic displacements, 〈u2〉, for Ni, Nb, Cu and Zr atoms are estimated. The interatomic interaction of the Ni and Cu atoms with respect to all neighbours is less than that of the Nb and Zr atoms. With decrease of the content of Ni and Cu atoms the differences of the average force constants in each system decline.