Chair of Non-Ferrous Metals and Gold, National University of Science and Technology “MISiS”, Moscow, Russia:

V. P. Tarasov, Head of a Chair, e-mail: vptar@misis.ru

A. S. Ignatov, Assistant

In the last years, technologies of obtaining of hard magnetic materials have been changed significantly. Output of magnetic products is constantly renewed both by the range, and by types. There are increased the requirements to these materials (especially to magnetic characteristics, residual induction and coercive force). As a result, the process of improvement of compositions for production of magnets with higher characteristics and reaching their properties on the level of global indicators is an urgent task. The carried out researches are aimed on the choice of efficient alloying additives, containing heavy rare metals, for improvement of characteristics of hard magnetic materials Nd – Fe – B. Application of solid-phase alloying technology allows to obtain the magnets Nd – Fe – B with high values of magnetic energy. Using 0.6–1.0% of additive Pr – Fe leads to increasing of residual induction Br and maximal value of magnetic energy (ВН)max by 3–4%. At the same time, the joint use of additives Tb – Ga – Cu – Al – Co and Pr – Fe allows to obtain the permanent magnets Nd – Fe – B with the level of magnetic energy of (ВН)max  400 kJ/m³. Optimal quantity of alloying additive is 1.5–2.0 %. At the same time, researches confirmed that the solid-phase alloying method (“method of impurities”) allows to obtain the high-efficient permanent magnets Nd – Fe – B with wide range of characteristics, which can be a prospective alternative to other alloying technologies, widely used by foreign manufacturers in the last years. 

This article was prepared within the fulfillment of Agreement about the subsidies (No.14.578.21.0037 of July 22, 2014; Unique identifier of the Agreement is RFMEFI57814X0037) between National University of Science and Technology “MISiS” and Ministry of Education and Science of Russian Federation, within realization of the Federal Target Program “Researches and developments on priority ways of development of scientific-technological complex of Russia for the period of 2014–2020”, approved by the Decree of the Government of Russian Federation of November 28, 2013 (No. 1096).

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