JPS59112602A - Permanent magnet - Google Patents

Abstract

PURPOSE:To provide high productivity and large coercive force and residual magnetic flux density, by a method wherein 100-crystal axis of alloy of Fe, Cr, Co, Al and the like in specific ratio is integrated in orthogonal direction to the laminated surface. CONSTITUTION:Laminated body of thin alloy is composed 15-35wt% Cr, 10- 50wt% Co, 0.2-9wt% one or more elements selected form the group of Si, Al, Ti, Zr, Hf, V, Nb, Ta, Mo and W and Fe in residue. The laminated body has the 100 crystal axis of the alloy integrated in orthogonal direction to the laminated surface. In the alloy thin band Cr is alpha-phase stabilizing element and also essential element to form spinodal non-magnetic phase. Co is essential element to form spinodal ferromagnetic phase and also control element for the spinodal decomposition temperature. Furthermore, element selected from the group of Si, Al, Ti promotes generation of 100-crystal surface flat plate aggregation composition of the permanent. In this constitution, the permanent magnet of Fe-Cr-Co series with high productivity and large coercive force and residual magnetic flux density is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a Fe-0r-Co permanent magnet. More specifically, the present invention relates to a laminated permanent magnet that is highly productive, has a large residual magnetic density and coercive force, has excellent square characteristics of hysteresis rings, and therefore has a large maximum energy product.

[Technical background of the invention and its problems]

A permanent magnet is required to have a high coercive force Hc and a residual magnetic flux density Br, and also have a rectangular hysteresis term line, that is, a large maximum energy product (B Hmax ). Such permanent magnets are made of alloys that have been given magnetic anisotropy by, for example, cooling treatment in a magnetic field.
Examples include alnico), intermetallic compounds (e.g., rare earth-cobalt magnets), and oxides (e.g., ferrite).

However, all of these permanent magnets have the disadvantage that they are mechanically fragile and are extremely difficult to machine, especially plastic work.

However, with the rapid development of electronics in recent years, permanent magnets of various shapes have come to be required. Therefore, it is desired to develop permanent magnets that have not only excellent magnetic properties but also excellent workability and formability, and are highly productive.

A spinodal decomposition type Fe-0r-Oo ternary magnetic alloy is one of the magnetic materials that is attracting attention as a permanent magnetic alloy that can be rolled or plastically worked.

This magnetic alloy is subjected to solution treatment (
After treatment (temperature: 1300°C), heat treatment in a magnetic field such as isothermal magnetic field treatment or cooling in a magnetic field is performed to perform so-called spinodal decomposition, and form single-domain fine particles of ferromagnetic phase in a non-magnetic matrix phase with shape anisotropy. It is manufactured by letting it stand and precipitate.

However, its productivity and magnetic properties were not necessarily sufficient. In other words, in the manufacturing process, deformation and cracking are likely to occur during the rapid cooling operation after the solution treatment, and the forming process requires repeating annealing and cold working, which reduces productivity. There was a problem.

Furthermore, during manufacturing, γ and α phases, which adversely affect magnetic properties, are likely to be mixed in, and the magnetic anisotropy is not sufficient.
It has the disadvantage that there is a limit to the improvement of the maximum energy product.

[Purpose of the invention]

An object of the present invention is to provide a Fe-0r-co permanent magnet with a laminated structure that has high productivity, high coercive force and residual magnetic flux density, and excellent squareness and magnetic anisotropy. be. [Summary of the Invention] The present inventors aimed to achieve the above object (Fe-0r-C.

As a result of extensive research into the composition and manufacturing method of magnetic alloys: Fe, Or, C, with specific compositions.

and 8i, A4 TI, Zr, Hf, V,
When the so-called molten metal quenching method is applied to alloy materials such as Nb, Ta, and Mo, α single-phase alloy ribbons with excellent formability can be easily obtained. By forming a structure in which the (100) crystal axis, which is the axis of easy magnetization, is accumulated perpendicularly to the ribbon surface, the magnetic properties are significantly improved: and by stacking this alloy ribbon in multiple layers,
They discovered that a (100) anisotropic permanent magnet can be easily obtained and completed the present invention.

That is, the permanent magnet of the present invention contains chromium (Or) 15 to 35
Weight%; Cobalt (Co) 10-50% by weight; Silicon (Si), Aluminum (AL), Titanium (Ti)
), zirconium (Zr), 1fnium (Hf),
Vanadium (v), niobium (Nb), tantalum (Ta
), 0.2 to 9% by weight of at least one element selected from the group of molybdenum (MO) and tungsten (W); and the balance substantially consisting of iron (Fe); A unique feature is that the (100) crystal axis of the alloy is concentrated in a direction perpendicular to the lamination plane.

The permanent magnet of the present invention is a laminate formed by laminating a plurality of thin alloy ribbons, which will be described later.

The present invention will be explained in more detail below.

In the alloy ribbon described above, Or is an α-phase stabilizing element and an essential element for forming a spinodal nonmagnetic phase.

Its content is 15-35% by weight. When the content is less than 15% by weight, no increase in coercive force is observed;
If it exceeds 5% by weight, the residual magnetic flux density and the maximum energy product will decrease, making it difficult to produce a thin ribbon.

Co is an essential element for spinodal ferromagnetic phase formation, and is also an element that controls spinodal decomposition temperature. Its content is 10-50% by weight. When the content is less than 10% by weight, the spinodal decomposition two-phase separation temperature decreases, resulting in a decrease in coercive force and maximum energy product. on the other hand,
If it exceeds 50% by weight, the coercive force decreases and it becomes brittle, causing manufacturing problems.

Si, A4 Ti, Zr, Hf, V, Nb,
At least one selected from the group 'Ta, Mo and W'
The seed element promotes the formation of the (100) crystal plane plate texture of the permanent magnet of the present invention. Its content is 0
．． It is 2 to 9% by weight. When the content is less than 0.2% by weight, the α phase [100] crystal axis is oriented perpendicular to the laminated plane (
100) The degree of agglomeration of crystal plane plate texture is significantly reduced.

Further, even if the degree of aggregation is satisfied, the (100) crystal orientation cannot be sufficiently reflected on the magnetic properties. On the other hand, if it exceeds 9% by weight, the residual magnetic flux density and coercive force of the obtained permanent magnet ribbon will be significantly reduced, and furthermore, the production of the ribbon will be extremely difficult.

The alloy ribbon preferably has a thickness of 10 to 500 μm. If the thickness is less than 10 μm, it will be difficult to manufacture a ribbon, and the degree of aggregation of the (100) crystal plane flat plate aggregated broken paper will decrease. If the thickness is 500 μm or more, the surface properties will be significantly reduced, making it difficult to form a high-quality laminate.

In the method for manufacturing a ribbon according to the present invention, first, a magnetic alloy having the above composition is melted according to a conventional method. Melting is carried out as appropriate by placing a powder or lump of each of the above elements in a predetermined order of magnitude in, for example, a quartz crucible, and heating the crucible with a high-frequency induction coil, xenon lamp, electron beam, arc discharge, or the like. The atmosphere during heating may be air, but it is preferable to introduce an inert gas such as argon and melt the material after it has been evacuated.

Next, the melt is formed into a thin ribbon using a melt quenching method. That is, as shown in FIG. 1, the melt 1 is transferred to a drum or roll 2 made of, for example, artanium, silver, copper, iron, or an alloy thereof and rotating at a circumferential speed of 1 z/sec or more.
ejects onto the rotating surface. And cooling rate 1000℃/
It is rapidly solidified at sec or more to form a thin ribbon. Through this process, the [100] axis of the α phase (body-centered cubic crystal) as shown in FIG. 3 changes from the initial state shown in FIG. The anisotropic ribbon changes to a columnar crystal structure oriented by the degree of aggregation, and has a (100) plane plate texture.

In the above process, the peripheral speed of the drum or roll is 1 m
If the cooling rate is less than 1000°C/sec, the surface will not be flat. 1↑, it becomes difficult to form a continuous film ribbon, and the cooling rate of the melt is 100%.
If the temperature is less than 0°C/Sec, solidification segregation will occur during cooling, and the generation of γ and α phases that adversely affect magnetic properties cannot be prevented, making it impossible to extract only the α phase in a single phase state to room temperature. It becomes difficult.

Furthermore, it becomes difficult to form a (100) plane plate texture consisting of a columnar crystal structure.

Next, the ribbon is usually cut to a predetermined size, and then stacked and annealed at a temperature of 1000 to 1300°C to form a columnar crystal structure (100).
The degree of agglomeration of the plane-plate texture is dramatically increased. This state is shown in FIG. 4, and by such treatment it is possible to increase the degree of aggregation to a state almost like that of a single crystal.

During this high-temperature annealing treatment, from the perpendicular direction to the contact surface of the (ioo) plane flat plate texture, for example, 0.01 to IOQOKg /
When a pressure of cm' is applied, a laminate in which each laminate surface is diffusion bonded at the interface can be easily obtained.

At that time, if the annealing treatment temperature is less than 1000° C., γ phase will be mixed in, and the magnetic properties will deteriorate. On the other hand, at a temperature exceeding 1300° C., some melting occurs, which not only deteriorates the magnetic properties but also is unfavorable from a thermoeconomic point of view.

When forming a laminate at the same time as the above annealing treatment, a bonding tube made of Co-8i or Fe-8i fine powder is inserted between the laminated surfaces of each ribbon, and pressure is applied to improve the bondability. It is also possible.

Furthermore, as an alternative method, each ribbon is not laminated, but is annealed at a high temperature and then laminated, and each ribbon is bonded with a heat-resistant organic adhesive, low melting point glass, low melting point alloy, etc. at a low temperature lower than room temperature. A laminate can be formed by joining the materials according to their advantages. Furthermore, it is also possible to join the multilayer ribbons together by mechanical methods such as sewing or fastening.

In the laminate, it is preferable that the air gap between each ribbon or the thickness of the bonding layer be 1 μm or less. This is because if the thickness exceeds 1 μIn, the demagnetizing field force increases and the usable magnetic flux density decreases.

The shape of the laminate thus obtained can be a flat plate, an annular ring, a corrugated plate, or various other shapes depending on its use, as shown in FIG.

Next, a magnetic field of 20,000 e or more is applied to the above-mentioned laminate in parallel to its α-phase [1oo] crystal axis, and heat treatment in the magnetic field is performed in a temperature range of 300 to 700°C. Hereinafter, the permanent magnet of the present invention from which a magnet can be obtained will be explained in detail along with Examples.

[Embodiments of the invention]

Examples 1 to 6 Six types of alloy materials of Examples 1 to 6 having the compositions (wt%) shown in Table 1 were placed in a quartz container equipped with a nozzle at the tip, and subjected to high frequency induction in an argon atmosphere. Each was melted by a heating method.

Each melt was maintained at a temperature 100° C. higher than the melting point of its composition, and the melt was jetted from a nozzle onto the rotating surface of a 300 mm diameter copper strip roll rotating at 5 Q Q rpn. The gap between the nozzle and the rotating surface was 0.1 an. Also, the peripheral speed of the copper piece roll is 7.5m/sec
The cooling rate was 104°C/sec. Through this treatment, continuous ribbons each having a smooth surface and a thickness of 100 μm were obtained.

A thin strip of 5 x 20 mm was cut to obtain a sheet of 5 x 20 mm, and 100 sheets each were stacked at a pressure of 0.1 Kg/crn2.
After performing vacuum annealing at a temperature of 100 to 1200° C. for 2 hours, the laminate was rapidly cooled at room temperature to obtain a laminate (thickness: about 1 cm). The X-ray diffraction profile of the laminated surface of this laminate is
Shown in Figure-1. For comparison, the X-ray diffraction pattern of the surface of the liquid-quenched ribbon before annealing is shown in FIG. 5-2. It is clear that the (1100·) plate texture has grown significantly due to the high-temperature annealing treatment.1 As is clear from the figure, the [100] axis of the alloy crystal was oriented perpendicular to the laminated plane.

Furthermore, in the laminate, the sheets were strongly bonded to each other.

Next, this laminate was heat-treated at 630°C for 15 hours in a magnetic field perpendicular to the laminated plane of 40,000e, and then at 600°C for 2 hours, and then heated at 580°C for 1 hour in the absence of a magnetic field. Next, aging treatment was performed at 560°C for 1 hour and then at 540°C for 8 hours to obtain an anisotropic permanent magnet of the present invention.

Regarding this permanent magnet, residual magnetic flux density (Br), coercive force (IHC) and maximum energy product ((BH)max
) was measured. The results are shown in Table 1. Moreover, these permanent magnets had excellent squareness.

Yinghuangdo↓Nii Six types of composite materials of Comparative Examples 1 to 6 having the compositions shown in Table 1 were melted, formed into thin strips, laminated, annealed, and aged in the same manner as in the examples. A permanent magnet was obtained. Regarding this permanent magnet, residual magnetic flux density (Br), coercive force (
rHc ) and maximum energy product ((BH)max )
was measured. The results are shown in Table 1.

As is clear from Table 1, the permanent magnet of the present invention has higher Br, Hc, and especially IHC than the permanent magnet of the comparative example, and therefore has a larger maximum energy product.

Comparative Example 7 Combined interest rate 2 of Comparative Example 7 having the same composition as Example 2
Kg was melted in a vacuum high frequency furnace by maintaining it at a temperature 100° C. higher than its melting point, and then cooled to room temperature to obtain an ingot. After hot forging, this ingot was solution-treated at 1300° C., simultaneously annealed at high temperature, and then rapidly cooled to room temperature to obtain an alloy plate. As a result of performing X-ray diffraction analysis on this plate surface,
No (100) texture was observed.

After this alloy plate was aged in the same manner as in Example 1, the residual magnetic flux density (Br), coercive force (IHC), and maximum energy product ((BH)max') were measured. The result is the first
Shown in the table.

As is clear from Table 1, the permanent magnet with the laminate structure of the present invention has a higher Br content than the permanent magnet obtained from the ingot alloy.
and Hc are both large, and therefore the maximum energy product is large.

〔Effect of the invention〕

As is clear from the above explanation, the permanent magnet of the present invention has:
Since the raw material is a highly flexible alloy ribbon, it can be easily laminated into any shape and has high productivity.
■It still has a laminated structure in which the (100) easy axis of magnetization is extremely oriented perpendicular to the laminated plane, so the residual magnetic flux density,
It has effects such as coercive force, inclination, and the hysteresis wire becomes rectangular, increasing p1 and therefore the maximum energy product, and its industrial value is extremely high.

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of the molten metal quenching method, Figure 2 is a schematic diagram showing the crystal structure in the initial state of ribbon formation, Figure 3 is a schematic diagram showing the crystal structure of the ribbon after cooling, and Figure 4 is annealing. A schematic diagram showing the crystal structure of the ribbon after treatment, Figure 5-1 is an X-ray diffraction profile diagram of the sample of Example 1 after annealing treatment, and Figure 5-2 is a diagram of the sample of Example 1 before annealing treatment. X-ray diffraction profile diagram of
The figures are schematic diagrams showing aspects of permanent magnets having a laminate structure according to the present invention having various shapes. 1-----1 melt, 2----
-One roll.

Claims (1)

[Claims] Chromium (Or) 1.5-35% by weight; Cobalt (C
o) 10-50% by weight; silicon (Sl), aluminum (At), titanium (TI), silconi-lamb (Zr
), 0.2 to 9% by weight of at least one element selected from the group of hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), molybdenum (Mo), and tungsten (W); and The remainder is essentially iron (F
A permanent magnet characterized in that it is a laminate of thin alloy ribbons consisting of e), and the (100) crystal axis of the alloy is stacked in a direction perpendicular to the lamination plane.