SU998570A1 - Magnetically hard alloy - Google Patents

Description

The invention relates to metallurgy, in particular, to hard magnetic alloys containing iron, cobalt and chromium, intended for the manufacture of permanent magnets, which can be used in electrical engineering, instrument making and other industries.

Known for deforming are alloys for permanent magnets based on the iron – cobalt – chromium system, alloyed with aluminum, vanadium, niobium, silicon, titanium, molybdenum, containing 8–25 Bcc. Co, with anisotropic magnetic properties. ,

The production of permanent magnets in these alloys requires a particularly complex technology, including high-temperature treatment for quenching and thermomagnetic processing, which hinders their mass production and manufacture.

Also known are wrought magnetically hard alloys of the iron-cobalt-chromium system with Mass (7-10 wt.%) Cobalt content and isotropic fermentation properties that do not require: complex thermomagnetic treatment 2.

The disadvantage of these alloys is the low level of magnetic properties.

which are within: residual induction BP 9.7-9.8 kG, coercive force H 330-400 Oe, with maximum magnetic energy

(, 4-1, in gs-e.,

The closest to the invention according to the technical essence and the achievable result is a deformable iron-based hard magnetic alloy containing b.%; chromium 26-28, cobalt 14.5-16.3 and doped with 3 wt.% molybdenum and other elements (aluminum, vanadium, niobium, titand, zirconium) Cz.

After dispersion hardening without thermomagnetic treatment, the coercive force of this alloy in an isotropic state can be increased.

20 to 440-520 E. However, a well-known alloy is characterized by a small value of the maximum magnetic energy ((.1.7 MGHE due to the low residual inductance of St. 9 KGs) and a low square of the demagnetization curve.

The known alloy requires a complex technology of obtaining magnetic properties in an isotropic state, including high-temperature hardening.

cooling ({at critical speed and prolonged aging ..

The aim of the invention is to increase the magnetic properties of a hard magnetic alloy in an isotropic state.

. The goal is achieved by the fact that the hard magnetic alloy 4 containing iron, cobalt, chromium and molybdenum, additionally contains gallium in the following ratio of xyponentes, wt.%:

Chrome22-30

Cobalt 14-16

Molybdenum 1-3,0

Gallium 0.5-3.0

Iron The rest and the total content of gallium and molybdenum 3-4 wt.%.

The addition of gallium alloy additionally to the composition makes it possible to increase the magnetic properties in the isotropic state, as well as to simplify the technology of their dispersion hardening, eliminating high-temperature processing and cooling at a critical rate.

Example. For the preparation of alloys, mixtures of ingredients containing, wt.% Alloy 1 Cr 22, Co 14, MO .3, GM 0.5, Fe total, were melted; alloy 2 -. Cr 25, Co 15 Mo 2, Gd 1, Fe - the rest; alloy 3 - Cr 30, Co 16, MO 1, ticx 3 D - the rest ..

The alloys were melted in an induction furnace in an argon atmosphere in the main crucibles. Crystallization of the ingot was carried out directly in the smelting crucible. The ingots were easily deformed in a hot and cold state for sample preparation: c.

 After production, samples in the form of rods with a length of 20.5 mm and a diameter of ~ 1.5 mm were processed according to mode 1m:

a) isothermal treatment in the temperature range 640-620С for one hour, followed by step aging: - 1 h +

5 + 580 ° С - i h + 560 ° С - 2 h +. + 540 ° С - 4 h;

b) holding at 0.5 h followed by quenching in

-10% alkali. (Con) + isothermal treatment in the temperature range of 640-620 ° C for one hour, followed by step aging: 600 ° C - 1 h + h + 560 s.-2 h + 540 ° C. - 4 hours

Magnetic properties of aged samples are given in the table. For comparison, the maximum values of the magnetic.-Characteristics are given. an isotropic state for a known alloy, as well as a value of the magnetic characteristics of the proposed alloy in an anisotropic state.

Jlpe Blue 1 12.0 400 3.5 480 480 2.5 600 3.6 Known

The table shows that the proposed alloy has a high residual induction (12000 Gy) after aging without a magnetic field from the deformed state (without high-temperature heating and hardening), high maximum magnetic energy (more than 3.0 MGs E) and an increased value of the coercive force ( 600 E). After quenching followed by isotropic aging,

of the alloy, a coercive force of 750 Oe is reached, and the maximum magnetic

Energy (., J., up to 3.8 MGs, which is significantly higher than that of the known alloy.

With isotropic aging from the hardened state, the proposed alloy increases by a factor of two the maximum magnetic energy and the coercive force in an isotropic state by 30%, 6,520 -2.8 16.06005.8 8.6 600 3.0 15.57508, 3 8.3 750. 3.8. 13.07206.0 7.5-9.0440-520 1.55-1.7

AI compared to limestone alloy.

The ability of the proposed alloy for magnetic hardening from the deformed state allows to significantly simplify the manufacturing process and reduce the cost of the production of magnets by 10-15%. At the same time, isotropic magnets from the proposed alloy, manufactured according to a simplified technology, have residual magnetic induction values of 20% and magnetic energy twice as large as that of isotropic magnets from a known alloy.

In addition, the lack of a controlled cooling operation eliminates the need to create special equipment, and the reduction in the duration of thermal treatment during aging leads to a 25–30% process productivity.

These advantages make it possible to use the proposed alloy in products obtained using the method of stamping from a sheet or drawing from a rod, followed by aging, which makes it possible to create a continuous production line for mass production.

Wa inexpensive magnets with a long range of applications.

Claims (1)

1. Sergeev V.V., Bulygina T.N. Hard magnetic materials. M., Energie, 1980, p. 195. 2.1oigpa, of, V. 52, 3, 1981, p, 2540. Z.zeye-Tgs1P9syu "VP, VP, tf. MAG -15, 2, 1979, p. 950.