Institute of Structural Macrokinetics and Materials Science of Russian Academy of Sciences, Chernogolovka, Russia:

M. I. Alymov, Director

A. A. Baikov Institute of Metallurgy and Materials Science of Russian Academy of Sciences, Moscow, Russia:

I. M. Milyaev, Leading Researcher

V. S. Yusupov, Head of Laboratory

Institute for Metals Superplasticity Problems of Russian Academy of Sciences, Ufa, Russia:

A. Kh. Nurislamov, Leading Engineer

The purpose of this review is to pay the attention of contemporary researchers and process engineers to Mn – Al hard magnetic alloys. The extensive research of Mn – Al hard magnetic alloys were made in the 1960–1970s. The alloys had great potential for practical application in various fields of industry due to sufficiently high values of the coercive force, along with the maximum magnetic energy, and due to the fact that source charge materials had a low cost. Only Japan and the USA have managed to produce these alloys because of the high cost of manufacture. After 1980s the interest to Mn – Al hard magnetic alloys was lost, which reason was the experts' forecast. They had predicted that the alloys, existed before industrial hard magnetic ones, including hard magnetic ferrites, would be replaced by Nd₂Fe₁₄B after the 2000s. However, this did not happen, and it will not apparently occur because of the limited resources of rare earth. In several cases, Mn – Al hard magnetic alloys can successfully replace magnetic alloys, based on rare earth compounds. Since the 1980s, the significant changes in the field of quality in alloy production technology have been made. It gives the hope that the cost of production of magnetic Mn – Al alloys will be reduced. The results of experimental technology of Mn – Al – C permanent magnet alloy are mentioned in this review briefly. This experimental technology was developed at the end of 1980s of the last century by one of the authors of this review in the Institute for Metals Superplasticity Problems of Russian Academy of Sciences (Ufa). For some reasons the technology has not been adopted in industry, but now it may serve as a good basis for the future development of these promising magnetic materials.

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