On the magnetic nanostructure of a Co–Cu alloy processed by high-pressure torsion

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Heinz Krenn
  • Lukas Weissitsch
  • Stefan Wurster
  • Reinhard Pippan

External Organisational units

  • Österreichische Akademie der Wissenschaften
  • Technische Universität Graz

Abstract

In this study, a preparation route of Co–Cu alloys with soft magnetic properties by high-pressure torsion deformation is introduced. Nanocrystalline, supersaturated single-phase microstructures are obtained after deformation of Co–Cu alloys, which are prepared from an initial powder mixture with Co-contents above 70 wt.%. Isochronal annealing treatments up to 400 °C further reveal a remarkable microstructural stability. Only at 600 °C, the supersaturated phase decomposes into two fcc-phases. The coercivity, measured by SQUID as a function of annealing temperature, remains significantly below the value for bulk-Co in all states investigated. In order to understand the measured magnetic properties in detail, a quantitative analysis of the magnetic microstructure is carried out by magnetic force microscopy and correlated to the observed changes in coercivity. Our results show that the rising coercivity can be explained by a magnetic hardening effect occurring in context with spinodal decomposition.

Details

Original languageEnglish
Pages (from-to)33-41
Number of pages9
Journal Journal of science / Vietnam National University / Advanced materials and devices
Volume6.2021
Issue numberMarch
Early online date28 Sep 2020
DOIs
Publication statusPublished - Mar 2021