Effect of W in Cu-Zr-W thin films: Molecular dynamics simulations and experimental verification

TL;DR

This study combines molecular dynamics simulations and experimental methods to explore how tungsten (W) influences the structure and mechanical properties of Cu-Zr thin film metallic glasses across various compositions and deposition conditions.

Contribution

It provides a comprehensive atomic-level understanding of W's role in modifying Cu-Zr metallic glasses and predicts optimal compositions for enhanced mechanical performance.

Findings

W incorporation affects atomic structure and stress distribution.

Optimal W concentrations improve hardness and elastic recovery.

Non-monotonic property dependencies on W content and deposition energy.

Abstract

We investigate the effects of W incorporation into Cu-Zr thin film metallic glasses using molecular dynamics (MD) simulations combined with magnetron sputtering. All studies are carried out in the whole range of W concentrations (0 to 100 at. %) and the MD studies also in a wide range of incident energies (1 to 500 eV) and deposition angles (0 to 60{\deg}). Calculated X-ray diffractograms, packing factor, short-range order (bonding fractions and coordination numbers), medium-range order (network ring and common neighbor statistics) and stress are correlated with measured X-ray diffractograms and properties (hardness, hardness/Young's modulus ratio and elastic recovery). The simulations explain the experimental results at the atomic level and provide a lot of information that is not available experimentally. Special attention is paid to non-monotonic dependencies on the elemental composition and incident energy. Collectively, the results explain the role of W in modifying the structure and improving the mechanical performance of Cu-Zr metallic glasses, predict optimum compositions which maximize some of the mechanical properties, and contribute to the development of advanced materials for various applications.