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arXiv · 2009.02932

Magnetic dilution by severe plastic deformation

Martin Stückler·Lukas Weissitsch·Stefan Wurster·Peter Felfer·Heinz Krenn·Reinhard Pippan·Andrea Bachmaier
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Abstract

Mixtures of Fe and Cu powders are cold-compacted and subsequently deformed with severe plastic deformation by high-pressure torsion, leading to bulk samples. The dilution of Fe in the Cu matrix is investigated with SQUID-magnetometry, whereas the magnetic properties change as a function of Fe-content from a frustrated regime to a thermal activated behaviour. The magnetic properties are correlated with the microstructure, investigated by synchrotron X-ray diffraction and atom probe tomography. Annealing of the as-deformed states leads to demixing and grain growth, with the coercivity as a function of annealing temperature obeying the random anisotropy model. The presented results show that high-pressure torsion is a technique capable to affect the microstructure even on atomic length scales.

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Martin Stückler, Lukas Weissitsch, Stefan Wurster, Peter Felfer, Heinz Krenn, Reinhard Pippan, Andrea Bachmaier. 2020-09-07. Magnetic dilution by severe plastic deformation. https://doi.org/10.1063/1.5128058

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