MENUSHENKOV Vladimir VSB - Technical university of Ostrava

Spoluautoři SHUBAKOV V.S.

The high-coercivity state of majority high-coercive Fe-Co-Cr alloys is formed during thermal magnetic treatment. However, as the Cr content in the alloys increases and results in the increase in the coercive force of magnets, the efficiency of the thermal magnetic treatment decreases, namely, the maximum energy product (ВН)мах decreases abruptly. The plastically deformed Kh33K16D2B alloy is among high-coercivity Fe-Co-Cr system alloys whose high magnetic properties are reached by deformation aging rather than the thermal magnetic treatment. This fact allows one to obtain high both Нс and (ВН)мах magnitudes [1,2]. The deformation-aging process developed by us for the alloy (wt%) 16 %Co-33%Cr-2%Cu-0,5%Nb- Fe (balance) includes the (1) quenching from 1100C to form the single-phase α solid solution, (2) aging resulting in the formation of spherical α1-phase precipitates during cooling in a temperature range of 650-625 оС at a rate of 40/h; (3) monoaxial plastic deformation with the 79% reduction of area in order to give the shape anisotropy of α1-phase precipitates and to produce the mechanical texture, and (4) final controlled cooling from 605 оС to 540 оС at a rate of 8о/h, in the course of which the more complete compositional separation of strongly magnetic α1-pahse and weakly magnetic α2-matrix precipitates is reached. The developed heat treatment allowed us to obtain the following magnetic characteristics of the Kh33K16D2B alloy: Нс = 805-810 Oe, Вr = 10,2-11,0 kG и (ВН)мах = 5,2- 5,3 MGOe. Literature: 1. Jin S., Gayle G.V., Bernardin J.E. Deformation-aged Cr-Co-Cu-Fe permanent magnet alloys. // IEEE Trans Mag., 1980, v. 16, P. 1050-1052. 2. Samarin B.A., Konev N.N., Shubakov V.S., Effect of plastic deformation on the magnetic properties of iron-chromium-cobalt-based alloys, Izv. Vyssh. Uchebn. Zaved., Chern. Metall., 1982, No. 11, pp. 155-156.