Structure of Alloys for (Sm, Zr)(Co, Cu, Fe)z Permanent Magnets and Formation Mechanism of High-Coercivity State

• Published in: Inorganic materials : applied research 2024-06, Vol.15 (3), p.851-865
• Main Authors: Dormidontov, A. G., Kolchugina, N. B., Dormidontov, N. A., Prokofev, P. A., Zheleznyi, M. V., Milov, Yu. V., Andreenko, A. S., Sipin, I. A., Bakulina, A. S., Telitsa, A. A.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; New Methods of Treatment and Production of Materials with Required Properties
• ISSN: 2075-1133; 2075-115X
• DOI: 10.1134/S2075113324700291

Contemporary research methods are used to study in detail the structure and phase composition of the (Sm, Zr)(Co, Cu, Fe) z alloys with z = 5.5–7.0 in the as-cast state and after heat treatment, which includes the solid-solution treatment at 1150–1180°C for 5 h, subsequent water quenching, isothermal aging at 800°C for 20 h, and cooling (stepped aging) from 800 to 400°C at an average rate of 100°C/h. The transformation scheme of boundary structural constituent of a (Sm, Zr)(Co, Cu, Fe) z permanent magnet manufactured by powder metallurgy technology is proposed for different heat treatment stages. The formation mechanism of the high-coercivity state of a permanent magnet in the course of complete cycle of heat treatments is given in the form of a sequence of phase transformations accompanied by the redistribution of a number of constituents of the (Sm, Zr)(Co, Cu, Fe) z alloy.