SU897400A1 - Method of making magnetic cores - Google Patents

Description

I

This invention relates to the technology of magnetic cores used in electronics as; radio components and magnetic elements of electronic equipment.

A known method of manufacturing magnetic cores consists in placing a ferrite insulating layer between the turns of the metal strip P.

Such a method of manufacturing magnetic cores does not allow obtaining cores with an offset self-returning magnetic hysteresis loop.

The closest to the invention of p6 technical essence and the achieved effect is the method of manufacturing magnetic cores, which consists in mixing powders of hard magnetic and magnet soft materials, pressing the mixture and sintering the cores, and the powder of the hard magnetic material is taken in the form of particles that do not dissolve during sintering. the bulk of the ferrite (fineness more than 1 mm) 2}.

A disadvantage of the known method of manufacturing magnetic cores is that it does not allow obtaining a heart (oscillators with an offset ca-i moving-loop magnetic hysteresis loop.

The purpose of the invention - obtaining mag-f

10 stranded cores with an offset self-returning magnetic hysteresis loop.

The goal is achieved by the fact that according to the method of manufacturing

IS of magnetic cores, including mixing of powders of hard magnetic and magnetically soft materials, pressing the mixture and sintering the cores, the sintered cores are subjected to thermomagnetic treatment at 400-600 ° С in a magnetic field of 10-100 Oe for 0.5-5 hours and cooled in a magnetic field with a speed of 0–200 s / h, and a material that acquires reduced magnetic anisotropy under the influence of thermomagnetic processing is used as a magnetic hard material. At the same time, in order to increase the coercive force, when mixing, a magnetically solid powder with a particle size of 0.050.1 mm is used. In addition, in order to increase the displacement of the hysteresis loop, a low-coercive metallic ferromagnet is used as a magnet of a soft material, and a magnet material with a perminevar effect is used to increase the output voltage pulse. Under the influence of thermomagnetic treatment fTMO), high-coercive particles of a magnetically hard material acquire uniaxial induced anisotropy and are magnetized in the direction of the field applied at TMT, in particular when TMO of toroidal cores in a circular field, in the direction of the doroid axis. Due to the high coercivity of the hard magnetic particles, the magnetization state created as a result of THO is retained after the TMT, including under the conditions of operation of the core. Magnetizing effect of magnetically hard material subjected to TMT on a magnetically soft matrix Decreasing the hysteresis loop of metallic ferromagnets parameter values (t 00 ° C 0. It biases the displacement of the hysteresis loop of the core. after removing the magnetic field. Example: Magnetic magnetics are made by mixing powders of hard magnetic and magnetically soft materials, by pressing. s and sintering of pressed cores. Sintered cores are subjected to thermomagnetic treatment. Tables 1-6 show the results of measurements of displacement of the hysteresis loop (in Oersteds and units of the coercive force Hp) obtained on the cores manufactured according to the proposed method at 1-st and intermediate values process parameters. As follows from the data presented in Tables 1-6, the proposed method for manufacturing magnetic cores provides the possibility of obtaining cores with an offset self-recurring loop magnet. hysteresis. The use of magnetic cores manufactured by the proposed method will reduce the size and weight of the products of radio electronic equipment on. Table оа on the basis of low-coercive orthified TMT with lower boundary, E, -t p, 0.5 h, d 200 ° C / h)

5EU OO4

Offset of the hysteresis loop of the cores) based on low-hermetic metal ferromagnets, pddverted TMT at the upper boundary values of the parameters,, and A. a b l and c a 2

Carbonyl iron

Annealed non-textured transformer steel,, 25% Offset hysteresis loop of serdemics based on non-coercive

metal ferromagnets subjected to TMT at. intermediate values of the parameters (, 9itgf ,, pp, 34, i {J)

5.5 6.1

0.9

5 18

0.3 5.5 1100 0.005

tit

13

13

U

, t a b l and c a 3

6.5

6.7

7.2

6.5 22

6 20 6.5 1300 6 1200

Offset of hysteresis loop of cores based on materials with perminereffect, subjected to TMT at lower Boundary values of parameters (, H 10 O, Ts, Aryzhki 0.5 h Dohd д 200H / h)

After TMO

Offset of the hysteresis loop of the hearts based on materials with a perminevoeffect, subjected to TMT at the upper boundary values of parameters, (t BOOE, H "100 3, tgj, eP; t: KH 5h, OT / h)

110

eleven

0.1 138 0.08

eleven

eleven

 After TMO

Table 5

130

13 13

120

163 150

3

/ f, 0

13

The offset of the hysteresis loop of cores based on materials with perminereffect, subjected to TMT at intermediate values of parameters (t, I 50 3, p, 3 h, PP,)

Table 6

Claims (4)

Claim 1. A method of manufacturing magnetic cores, comprising mixing powders of magnetically hard and soft materials, pressing the mixture and sintering the cores, characterized in that, in order to obtain a biased self-reversing loop of magnetic hysteresis, the sintered cores are subjected to thermomagnetic treatment at 400 ° -00 ° C in a magnetic field of intensity 10100 ° O β for 0.55 h and cooled in a magnetic field at a speed of 40200 ° C / h, and as a magnetically hard material: use material acquiring induced magnetic aniso tropia under the influence of thermomagnetic processing. 2. The method of pop. 1, characterized by the fact that, in order to increase coercive force, when mixing 25 use a hard magnetic material powder with a particle size of 0.05 “0.1 mm. 3. The method of pop. 1, characterized in that, in order to increase the displacement of the hysteresis loop, 6 a low-coercive metal ferromagnet is used as a magnetically soft material. 4. The method according to claims 1 and 3, about t l and - 35 characterized in that, in order to increase the output voltage pulse, a material with a perminvar effect is used as a soft magnetic material.