Correlation between mechanical, thermal and electronic properties in Zr–Ni, Cu amorphous alloys

Abstract

We show that mechanical properties (stiffness and hardness) of Zr–Ni, Cu amorphous alloys increase linearly with Ni, Cu content over a wide composition range (22 ≤ x _Ni,Cu ≤ 65 at%). This correlates with the observed increase in the Debye temperatures and densities with x and shows that the strength of interatomic bonding increases with x in these alloys. Accordingly, the thermal stability (e.g. the crystallization and glass transition temperatures) of these alloys also increases with x. Since the electronic density of states at the Fermi level decreases linearly with x within the same x-range, a very simple relationship exists between the electronic structure and mechanical and thermal properties. We also deduce the mechanical properties of hypothetic amorphous Zr and briefly discuss the possibility of its preparation.

Acknowledgements

We thank Dr I. Bakonyi for stimulating discussions and Dr A. Kuršumović for the measurements of Young's modulus.