Thermokinetic stabilisation of nanocrystalline Cu by ternary approach

ABSTRACT

Nanocrystalline alloy design with the synergistic contribution of ‘thermodynamic’ and ‘kinetic’ stabilisation mechanism leads to much superior microstructural stabilisation at elevated temperatures. Ternary Cu_98.5W₁Zr_0.5 (at. %) alloy, synthesised by mechanical milling under cryogenic temperature followed by consolidation through hot pressing at 550°C, has been examined to access the potential of their concurrence. A meager drop in hardness (∼0.5 GPa) confirms the stability of the alloy up to 800°C. The effect of alloy addition has been studied in terms of microstructure alteration, measured by X-ray diffraction, transmission electron microscopy, and Molecular dynamics (MD) simulation. In addition, the shear punch test (SPT) has been employed to assess the mechanical property of the consolidated alloy. Results suggest that the current approach provides a framework en route to designing bulk nanostructured alloys adapting the bottom-up method.

KEYWORDS:

• Nanocrystalline alloy
• grain growth
• hardness
• grain boundary segregation
• grain boundary pinning

Acknowledgment

We thank Professor Carl C Koch, NCSU, Raleigh for providing needful research facilities and valuable suggestions. DR thanks the Indo-US fellowship programme for providing needful financial support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.