SU1294479A1 - Method of producing elastic permanent magnets - Google Patents

Abstract

The invention relates to powder metallurgy, in particular, to a method for producing resilient permanent magnets. The aim of the invention is to increase the magnetic force of the elastic magnets. The proposed method consists in mixing a dispersed magnetically hard material with a polymer binder and extruding the mixture obtained under the simultaneous action of two or more oppositely directed permanent or pulsed non-uniform magnetic fields created by passing along linear conductors 1.5-2 in diameter, 0 mm of direct current of 5-25 A or pulsed current of 15-100 A. 2 Il. 3 tab. i (L

Description

The invention relates to powder metallurgy, in particular, to methods for producing elastic anisotropic permanent magnets by extrusion of a mixture of a powder of a magnetically hard material with a polymer binder, and can be used in mechanical engineering, instrument making, the electrical and radio engineering industry in the manufacture of sealing elements and seals.

The purpose of the invention is to increase the magnetic attraction force of elastic magnets.

FIG. 1 and 2 show a magnetic field topography, explaining the essence of the method.

The invention is based on the ability of the particles of a magnetically hard material, having a single-domain structure, to be oriented by the axes of easy magnetization along the lines of force of an external magnetic field. Since the lines of force of the magnetic field arising in a conductor with current are located in concentric circles centered on the axis of the conductor, the particles of a hard magnetic material in this case are oriented axially to the conductor cross section. In the presence of two or more conductors, through which currents are passed in opposite directions, the magnetic fields interact between themselves with the same poles.

The topography of a magnetic field created by two conductors with a current is shown in FIG. 1. The creation of an axial texture in a polymeric material filled with magnetically hard particles increases the anisotropy of the magnetic properties and the strength of the magnetic attraction of multi-pole elastic magnets. It has been established experimentally that the maximum value of the magnetic attraction force in elastic magnets is realized when magnetic fields are created during extrusion by passing a constant current of 5-25 A or a pulsed current of 15-100 A through linear conductors 1.5-2-2 in diameter. mm

A decrease in the diameter of the magnetizing conductor (less than 1.5 mm) and / or an increase in its diameter (more than 2.5 mm leads to a decrease in the magnetic force of elastic magnets. A decrease in the strength of a constant (less than 5 A) and pulsed (less than 15 A) currents and / il

five

0

five

0

five

0

five

O

five

an increase in the strength of a constant (more than 25 A) and pulsed (more than 100 A) currents also leads to a decrease in the magnetic attraction force.

The proposed method is carried out as follows.

Bary ferrite powder is mixed with a polymeric binder, which is polyvinyl chloride (PVC), plasticized dioctyl phthalate (DOP), or SraCo powder with polyurethane (PU). The mixture obtained is extruded on a screw press, in an extrusion die of which two or four linear conductors with a current producing magnetic fields are placed in the direction of extrusion. Conductors with current are supplied from a DC source (U O - 250 V, P 6.5 kW), or from a battery of capacitors (µF, V). Samples are obtained in the form of rectangular sections of 4x9.5 mm (three-pole magnetization) and 3.2 x X 13 mm (n-type magnetization). The resulting samples are magnetized using inductors, creating a field of similar topography. During the extrusion process, the conductors with current are in contact with the surface of the material to be worked, creating in it a non-uniform magnetic field with a gradient of intensity in the radial direction (Fig. 1). The minimum value of the magnetic field at a distance of 1 mm from the conductor at a current J 5 A is H 1.2 kA / m, the maximum at J 100 kA / m.

The proposed method makes it possible to obtain lengthy elastic magnets with a given distribution of the magnetic field along the generatrix, for example, in the form of round rods with the location of the poles along a helix (Fig. 2). In this case, the texturing magnetic field is created by passing oppositely directed currents along conductors 1 and 2 located along a helix that covers the cylindrical profile of an elastic magnet 3 that is unscrewed from the shaping head. In this case, the axially opposite currents in the direction, but with the same magnitude, the magnetic fields mutually compensate each other in the direction of the axis of the solenoid formed by bifillary winding, and their interaction with the extruded material in the contact zone leads to the formation of axial ( relative to the conductor axis) texture.

The test results are shown in Table. one.

From tab. 1 it follows that the strength of the magnetic attraction of elastic constants. These magnets obtained by the proposed method by passing a current through a two (three-pole magnet) or four (a typical magnet) wire 10

are given in table. 2 also does not allow for a noticeably improved magnetic attractive force of elastic permanent magnets as compared with the known method.

The maximum value of the magnetic force is realized in the case of equality of the magnitude of the oppositely directed currents.

The test results are shown in Table. 2 and 3.

The use of the proposed method of obtaining elastic permanent magnets allows to increase the efficiency

seals in various industries.

nicknames (examples 1-6) are better than when they are used as magnetic radiation in a known manner. Thus, in the case of obtaining magnets from barium ferrite (examples 1, 3, and 5), the proposed method allows one to obtain a magnetic attraction of 80–110 g / cm 20 (for a three-pole magnet) and 85 - 115 g / cm (for p-type magnesium - ta) compared to 70 g / cm for magnets obtained in a known manner. A similar dependence is observed 25 and for elastic magnets from SmCOj (the magnetic force of 360-530 g / cm when obtained by the proposed method versus 165-173 g / cm when obtained is known) .30

F o rm u la invention

A method of manufacturing resilient permanent magnets, comprising mixing dispersed magnetically hard material with a polymer binder and extruding the resulting mixture under simultaneous exposure to magnetic fields, characterized in that, in order to increase the magnetic force of the elastic magnets, the mixture is extruded under two or more oppositely directed constant or pulsed inhomogeneous magnetic points are given in Table. 1 it also follows that when going beyond the limits of the proposed values (examples 8-14), a noticeable increase in the strength of the magnetic attraction, according to jj lei, generated by

compared with the known method is not observed. The use of only one conductor with current (bipolar magnetization), as shown by the data.

PVC 6; DOP 4; WAO. 6 90

PU 10; SmCOg 90

PVC 6; DOP 4; BaO 6 90

are given in table. 2 also does not allow for a noticeably improved magnetic attraction force of elastic permanent magnets as compared with the known method.

The maximum value of the magnetic force is realized in the case of equality of the magnitude of the oppositely directed currents.

The test results are shown in Table. 2 and 3.

The use of the proposed method for producing elastic permanent magnets makes it possible to increase effective sealing materials in various industries.

their use as a mag

their use as a mag

F o rm u la invention

A method of manufacturing resilient permanent magnets, comprising mixing dispersed magnetically hard material with a polymeric binder and extruding the resulting mixture under simultaneous exposure to magnetic fields, characterized in that, in order to increase the magnetic force of the elastic magnets, the extrusion of the mixture is carried out when exposed to two or more oppositely directed constant or pulsed inhomogeneous magnetic cores along linear conductors with a diameter of 1.5-2.0 mm of direct current of 5-25 A or pulsed current strength of 15-100 A.

Table 1

15

1.5 1.5

2.5

80 85 360 375

98

100

BaO - 6, 90 PU 10, SmCo..90

17

With extreme values

9 10

11 12 13

14

the famous

15 16

PVC 6; DOP 4; BaO-6 FejO 90

PVC 6; DOP 4; BaO - 6, 90

PVC 6i DOP 6; BaO-, 90

PVC 6i DOP 4-, VAO - 6 90

PU10 jSmCoj90

PU10; SmCOg90

PU10-SmCOj90

PU10; SmCo590

PVC 6i DOP 4; BaO 6 FegO, 90

PU 10, SmCo 90

thirty

15

70 165

73,173

Note. Examples 1-3,7 use material

on the basis of polyvinyl chloride and barium ferrite, in examples 4-6, 8 - on the basis of polyurethane and SmCo powder.

Table 3

Note. In examples 1 and 2 use material on

on the basis of polyvinyl chloride and barium ferrite, in examples 3-4 - a material based on polyurethane and SmCoj powder.

table 2

FIG. 2

Compiled by E. Zalmanova Editor N. Margolina Tehred M. Khodanych Corrector I. Erdeyi

Order 420/9 Circulation 741 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Claims (1)

Claim A method of manufacturing elastic permanent magnets, comprising mixing a dispersed hard magnetic material with a polymeric binder and extruding the resulting mixture under the influence of magnetic fields, characterized in that, in order to increase the force of magnetic attraction of the elastic magnets, the extrusion of the mixture is carried out when two or more opposite exit outside the proposed values (examples 8-14) a marked increase in the force of magnetic attraction, compared with the known method is not observed. The use of only one conductor with current (bipolar magnetization), as shown by the data, but directed by constant or pulsed inhomogeneous magnetic fields created by passing through DC conductors with a diameter of 1.5-2.0 mm of 5-25 A power or pulse current of 15-100 A. Table 1 Example The ratio of the components of the extrudable mixture, wt.% • Current strength, _L , A Conductor diameter mm permanent impulse The force of magnetic attraction, F, g / cm ² Three pole magnet Five pole magnet Proposed 1 PVC 6; DOF 4; BaO6 Fe ₂ 0 ₃ 90 5 - 1,5 80 85 2 PU 10; SmCo _s 90 - fifteen 1,5 360 375 3 PVC 6; DOF 4; BaO - 6 Fe ₂ 0 ₃ 90 25 2,5 98 100 1294479 ft Continuation of table 1 Example The ratio of the components of the extrudable mixture, wt.% • Current strength, 1 _p , A Conductor diameter mm The force of magnetic attraction, F, g / cm ² permanent impulse Three pole magnet five pole magnet 4 PU 10; SmCOj. 90 - 100 ‘2.5 440 450 5 PVC 6; DOF 4 -, BaO 6 Fe ₂ 0 _b 90 17 - 2.0 110 115 6 PU 10, SmCo ₅ .90 - 70 2.0 520 530 With outrageous values - 7 PVC 6; DOF 4; BaO-6Fe ₂ O ₃ 90 3 - 2.0 65 67 8 PVC 6; DOF 4; BaO '6 Fe ₂ 0j 90 ^thirty - 2.0 70 72 9 PVC 6; DOF 6; BaO6 Fe ₂ 0 ₃ 90 7 - 1,0 70 73 10 PVC 6; DOF 4 ·, BaO · * 6 Re ₂ 0 ₃ 90 fifteen - 2,8 72 75 eleven PU 10 '; SmCo ₅ 90 - 10 2.0 160 165 12 PU 10 SmCo _s 90 - 120 2.0 170 178 thirteen PU 10; SmCo ₅ 90 - fifty 1,0 172 177 14 PU 10; SmCo _s 90 - 70 2,8 175 179 Famous fifteen PVC 6; DOF 4; BaO6 Fe ₂ 0 ₃ 90 - - - 70 73 16 PU 10, SmCo ₅ 90 - - 165 173 table 2 Example Current strength, A Conductor diameter mm f The force of magnetic attraction, g / cm ² of permanent impulse Proposed 1 5 2.0 70 2 17 • 2.0 73 3 25 2.0 74 4 fifteen 2.0 168 5 fifty 2.0 172 6 100 2.0 170 Famous 7 - - - 69 8 - - - 160 Note. In examples 1-3,7 use a material based on polyvinyl chloride and barium ferrite, in examples 4-6, 8 - based on polyurethane and SmCo ₅ powder. Table 3 Example Amount of current, A, in the conductor The force of magnetic attraction, g / cm ² first | second 1 17 7 75 2 17 17 110 3 70 (impulse) 20 (impulse) 190 4 70 (impulse) 70 (impulse) 520 Note. Examples 1 and 2 use a material based on polyvinyl chloride and barium ferrite, and examples 3-4 use a material based on polyurethane and SmCo ₅ powder. E. Zalmanova