Tailoring the magnetic properties of nanocrystalline Cu-Co alloys prepared by high-pressure torsion and isothermal annealing

TL;DR

This paper explores how high-pressure torsion and annealing can be used to tailor the magnetic properties of nanocrystalline Cu-Co alloys, with detailed microstructural analysis and additional deformation techniques for property tuning.

Contribution

It introduces a novel combination of severe plastic deformation and annealing to control the nanostructure and magnetic properties of Cu-Co alloys.

Findings

Phase separation occurs after annealing of supersaturated solutions.

Magnetic properties are correlated with nanostructure evolution.

Additional deformation at low temperature further tunes magnetic behavior.

Abstract

In this study, severe plastic deformation by high pressure torsion is used as a fabrication method for nanocrystalline magnetic CuCo alloys in bulk quantities. By subsequent isothermal annealing, phase separation of the supersaturated solid solutions can be obtained. The magnetic properties of the as-processed and annealed materials have been studied systemically and correlated to the evolving nanostructures investigated in detail by transmission electron microscopy and atom probe tomography. By additional high pressure torsion deformation at liquid nitrogen temperature the magnetic properties of the Cu74Co26 alloy can be further tuned.