Abstract
High-power (Nd, Dy)–(Fe, Co)–B permanent magnets with a low temperature coefficient of induction (α) were prepared using advantages of strip casting and low-oxygen technologies. The microstructure and temperature dependences of magnetic properties have been studied on sintered (Nd1 – x Dy x )13.9(Fe1 – y Co y )79.8Cu0.1Ga0.1B6.1 magnets with 0.20 ≤ x ≤ 0.25 and 0 ≤ y ≤ 0.20. The increase in y from 0 to 0.20 is accompanied by an increase in the Curie temperature from 327 to 492°C. This favors a decrease in the value of α from 0.099 to 0.060%/°C, respectively. Magnets with an oxygen content of no more than 2500 ppm which were prepared from the (Nd0.75Dy0.25)13.9(Fe0.85Co0.15)79.8Cu0.1 Ga0.1B6.1 alloy, have the following hysteresis characteristics at 140°C: B r ≥ 11.3 kG, H c ≥ 8 kOe, and (BH)max ≥ 30 MGOe; in this case, α ≤ |–0.07%/°С|.
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Original Russian Text © A.G. Popov, D.A. Kolodkin, V.S. Gaviko, D.Yu. Vasilenko, A.V. Shitov, A.V. Vlasyuga, M.Yu. Govorkov, D.Yu. Bratushev, 2017, published in Fizika Metallov i Metallovedenie, 2017, Vol. 118, No. 10, pp. 981–992.
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Popov, A.G., Kolodkin, D.A., Gaviko, V.S. et al. High-power (Nd, Dy)–(Fe, Co)–B magnets with a low temperature coefficient of induction. Phys. Metals Metallogr. 118, 935–945 (2017). https://doi.org/10.1134/S0031918X1710009X
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DOI: https://doi.org/10.1134/S0031918X1710009X