Abstract
Thermomagnetic analysis and Mössbauer spectroscopy were used to study the effect of severe plastic deformation (SPD) by high-pressure torsion (HPT) and subsequent annealing on structural transformations and formation of magnetic properties of rapidly quenched Nd9Fe85B6 alloy. The HPT of the Nd9Fe85B6 amorphous alloy was found to result in the precipitation of α-Fe nanocrystals and in changes in the structural state of the residual amorphous phase A′. In the annealed samples, there was revealed a great amount of nonequilibrium phases with different magnetizations. The total content of nonequilibrium phases depends on the annealing temperature and affects the exchange interaction between magnetically soft α-Fe nanocrystals and Nd2Fe14B nanocrystalline grains. The results obtained in this study can explain the differences between the high level of hysteresis properties of nanocrystalline materials, which was predicted theoretically, and low magnitudes realized in practice.
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Original Russian Text © A.G. Popov, V.V. Serikov, N.M. Kleinerman, 2010, published in Fizika Metallov i Metallovedenie, 2010, Vol. 109, No. 5, pp. 542–550.
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Popov, A.G., Serikov, V.V. & Kleinerman, N.M. Thermomagnetic and Mössbauer studies of structural transformations caused in the amorphous Nd9Fe85B5 alloy by severe plastic deformation and annealing. Phys. Metals Metallogr. 109, 505–513 (2010). https://doi.org/10.1134/S0031918X1005011X
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DOI: https://doi.org/10.1134/S0031918X1005011X