Intermixing of Fe and Cu on the atomic scale by high-pressure torsion as revealed by DC- and AC-SQUID susceptometry and atom probe tomography

• Published in: Acta materialia Vol. 196; pp. 210 - 219
• Main Authors: Stückler, Martin, Krenn, Heinz, Kürnsteiner, Philipp, Gault, Baptiste, De Geuser, Frédéric, Weissitsch, Lukas, Wurster, Stefan, Pippan, Reinhard, Bachmaier, Andrea
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2020; Elsevier
• Subjects: Condensed Matter; High-pressure torsion; Materials Science; Nanocrystalline materials; Physics; Severe plastic deformation (SPD); Spin glass; Three dimensional atom probe (3DAP); Spin glass; Three dimensional atom probe (3DAP); Severe plastic deformation (SPD); Nanocrystalline materials; High-pressure torsion
• ISSN: 1359-6454; 1873-2453
• DOI: 10.1016/j.actamat.2020.06.035

[Display omitted] The capability of high-pressure torsion on the preparation of supersaturated solid solutions, consisting of Cu-14Fe (wt.%), is studied. From microstructural investigations a steady state is obtained with nanocrystalline grains. The as-deformed state is analyzed with atom probe tomography, revealing an enhanced solubility and the presence of Fe-rich particles. The DC-hysteresis loop shows suppressed long range interactions in the as-deformed state and evolves towards a typical bulk hysteresis loop when annealed at 500∘ C. AC-susceptometry measurements of the as-deformed state reveal the presence of a superparamagnetic blocking peak, as well as a magnetic frustrated phase, whereas the transition of the latter follows the Almeida-Thouless line, coinciding with the microstructural investigations by atom probe tomography. AC-susceptometry shows that the frustrated state vanishes for annealing at 250∘ C.