JPH04142705A - Manufacture of permalloy core - Google Patents

Abstract

PURPOSE:To obtain a permalloy wound-core, having a highly stabilized magnetic properties, E and I cores and the like by a method wherein a slit-forming work is conducted on a permalloy thin band wide in width on which annealing-isolation coating is provided in the prescribed film thickness range, and after a winding work or a punching work is conducted thereon, a magnetic annealing operation is conducted at the prescribed temperature. CONSTITUTION:An annealing isolation coating is applied at least on one surface in the thickness of 0.1 to 50mum. When an annealing isolation agent is applied on an original sheet, the time required for manufacture of a wound core is cut down, magnetic characteristics is easily stabilized in high degree, and the irregularity of space factor and the like is lessened. Also, when E and I cores and the like are manufactured, Al2O3 fine powder is not applied to every punched small piece, and after they are continuously punched out, they are mechanically laminated and magnetically annealed. The desired temperature of the above-mentioned magnetic annealing is 1000 to 1300 deg.C from the view point of annealing effect and the retention of mechanical strength of permalloy. Also, when Mg(OH)2 is used as the main component of an annealing isolation agent, a lubricating action can be displayed when slit-forming, punching, bending and drawing operations are performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a permalloy core (soft magnetic Ni-Fe alloy core).

[Conventional technology]

Permalloy has high magnetic permeability and is used in large quantities as a magnetic core material mainly for weak electric current applications. Conventionally, permalloy cores are generally uncoated wide coils that are slit to the final width, and then processed into wound cores, punched, bent, drawn, etc. to give the final shape. and 1000-1300℃
After being heated to a temperature of 100 mL to remove internal strain and further remove impurities, so-called magnetic annealing is performed, and the material is made into a magnetic core material and incorporated into equipment.

When such magnetic annealing is performed, the workpieces are stacked and placed in the furnace, so the parts between the workpieces and even the areas where they come into contact with the metal container are burned due to the high heat. Therefore, for example, in the case of a rolled core, after slitting it to a predetermined final width, it is degreased, immersed in a slurry bath made of alumina, magnesia, etc. and water, dried, and then wound to a predetermined diameter. , subjected to magnetic annealing.

In addition, when manufacturing magnetic cores such as E and I cores, E,■
After punching the mold, the punching oil is removed, and a fine powder of alumina, magnesia, etc. is applied to the mold and the mold is subjected to magnetic annealing.

The shielding material is also subjected to magnetic annealing after being degreased, bent or drawn into a predetermined shape, and then a similar annealing separating agent is applied to predetermined locations.

[Problem to be solved by the invention]

As mentioned above, in the conventional method, for example, in the case of a rolled core, degreasing, coating, drying, and winding processing after slitting the final width are required for each core, which is not only extremely time-consuming and inefficient. The thickness of the coating varies from core to core or from location to location, and the pressure applied during winding tends to be uneven, leading to problems such as deterioration of the final magnetism. Furthermore, in the case of shielding materials such as E and I cores, they are generally degreased, coated, and dried individually after being made into small magnetic cores, which in practice requires extremely complicated and inefficient work.

SUMMARY OF THE INVENTION In view of the problems of the conventional method described above, it is an object of the present invention to provide a method for efficiently manufacturing permalloy wound cores, E, (2) cores, etc., which have highly stable magnetism.

[Means for Solving the Problems] The gist of the present invention is basically to shift the timing of applying an annealing separator, and further provides a means for more effectively realizing the timing shift. It is something to do.

That is, the gist of the present invention is that the film thickness is from 0.1 to
A wide permalloy ribbon with a 50 μm annealing separation coating applied to at least one surface is slit to the final width, then rolled or punched, and further bent and drawn as necessary. The method for producing a permalloy core is characterized in that, after applying an auxiliary annealing separator to the processed sheared surface as necessary, magnetic annealing is performed at a temperature of 1000 to 1300°C.

In the conventional method, an annealing separator is applied after slitting the wound core, E, I core, or shield core to the final width, whereas in the present invention, the annealing separator is already applied when the core is slit to the final width. It is characterized by the fact that it has been found to be coated with a polyurethane resin, and as a result, it has been found to lead to many advantages.

Permalloy in the present invention may be any Ni-Fe alloy, but in order to manufacture a magnetic core or shield material with high magnetic permeability, it is necessary to use a Ni-Fe alloy with a Ni content of 40 to 90%.
Alloys such as Mo, Cu+Co, and Si are preferred.

It may also contain additive elements such as Cr, Mn, B, V, Nb, and Ti. Further, the thickness of the permalloy ribbon is not particularly limited, and is usually, for example, 0.0
5. From the so-called foil of about 1 pavilion to the thick part. Ott
It is about m. Regarding the board width, there is no particular limitation as long as it is a width that allows multiple strips to be taken in the final width.
It has a wide range of about 0 to 1200 m, but usually 50 to 7 m.
Hereinafter, for convenience, these original coils will be referred to as wide coils. It goes without saying that for the purposes of the present invention, the annealing separation coating applied to such a ribbon may be applied to only one surface or both surfaces as long as it has an annealing separation effect.

The reason why the thickness of the coating was limited to 0.1 to 50 μm was 0.1 μm.
This is because if it is thinner than μm, it cannot function as an annealing separator sufficiently, and if it is thicker than 50 μm, the space factor is significantly impaired.

The main components of the annealing separation coating used in the present invention are not particularly limited in claim 1, and are conventionally used after narrow slitting and degreasing (in the case of a rolled core), or after slitting, punching, bending, drawing. A method performed after processing and oil washing (E, I core, etc.) may be used, that is, one or more fine powders of alumina, magnesia, magnesium hydroxide, calcium oxide, calcium hydroxide, titanium oxide, etc. A method of immersing a wide coil in a solution in which water is suspended and then evaporating the water, or a method of evaporating the water using an organometallic compound as proposed in Japanese Patent Application Laid-Open No. 121670/1983 for a narrow coil. Alternatively, a method may be used in which the material is immersed in a liquid consisting of at least one kind selected from the decomposed products thereof and then dried.

One use of permalloy ribbon is to slit the permalloy into the final use width of several to several tens of squares, coat it with alumina fine powder slurry, dry it, wind it to a predetermined diameter of several to several hundred squares, and then magnetically annealing it. to make various magnetic cores.
There is a so-called rolled core. When the annealing separator is coated on the wide coil of the original plate, as in the starting material of the present invention, the time required to manufacture the wound core is shortened. That is, in the past, there was a limit to the winding speed due to coating and drying, but in the present invention, after slitting to the final width, the core can be formed into a predetermined rolled core at high speed.

This method not only saves time, but also makes it easier to make the coating thickness and winding pressure uniform, so the magnetic properties tend to be more stable at a higher level, and there are also advantages such as less variation in space factor, etc.

In addition, as another use for permalloy thin strip, after slitting permalloy into the final use width of several to several tens of widths,
For example, E and I cores are punched, coated with fine powder of AI, O, etc. as an annealing separator, subjected to magnetic annealing, and used as a small transformer. Like the starting material of the present invention, E, T
When manufacturing cores, etc., for example, there is no need for complicated processes such as applying A1t03 fine powder to each punched piece as in the conventional process, and after continuous punching, mechanical processing is performed. If they are laminated or subjected to magnetic annealing, a significant improvement in work efficiency can be obtained.

In the case of the present invention, it is basically unnecessary to apply an annealing separator immediately before magnetic annealing as in the conventional case, but if seizure of the slit end face, punched end face, etc. becomes a problem, for example, it may be necessary to apply an annealing separating agent as required. It is also possible to supplementally apply an annealing separator only to those areas. It goes without saying that the load required for such auxiliary application is much lighter than that required for conventional methods.

The lower limit of temperature during magnetic annealing was set at 1000°C because if it is less than that, strain release and purification will not be achieved sufficiently, and if it is higher than 1300°C, it will soften and the strength of permalloy will not be maintained. The temperature was 1000-1300°C.

The time is usually about 1 to 3 hours, but in the case of high temperature, it may be about several minutes.

In the present invention, the annealing separator used to form the annealing separation coating for the wide permalloy ribbon contains magnesium hydroxide (Mg(OH)z) as the main component.
), the effects of the present invention are doubled.

Therefore, in the method according to any one of claims 1 to 3, the permalloy core is characterized in that the main component of the annealing separation coating applied to the surface is magnesium hydroxide (Mg (OH) t). The manufacturing method is described in claim 4.

The reason why Mg(OH)z is used as the main component of the annealing separator is that not only is it hydrolyzed during the temperature rising process during magnetic annealing to become MgO with good annealing separability, but Mg(OH)z itself is alumina (AZzOz). ) This is because it is easier to form a coating with good adhesion to the permalloy base compared to other annealing separators. In addition, the most important reason for using Mg (OH) t in the present invention is that Mg (Otl) z itself has an excellent solid lubricating effect, so it can be used during slitting, punching, bending, and drawing. 0. This is because not only does it not have negative effects such as abrasive effects, but it also exhibits a lubricating effect. This effect not only extends the life of machining tools, but also makes it possible to simplify and omit the use of conventionally used slit lubricating oil, punching lubricating oil, etc. There are cases in which the washing process and the like may necessarily be omitted, and the effects can be very large.

In order to obtain a coating containing Mg (OH) z as a main component, a slurry solution consisting of water and Mg (OH) z may be applied. At this time, MgO, AlzCh
, CaCoz, and other ceramic fine powders may be mixed to some extent.

In addition, using a solution in which one or more of binders, thickeners, and antifoaming agents are selected and added as necessary to the slurry improves adhesion to the permalloy substrate, coatability, etc. Preferably, therefore, the method according to claim 4, wherein the annealing separation coating comprises water, Mg(OH),
It is characterized by being obtained by coating a slurry consisting of MgO with a solution containing one or more selected from binders, thickeners, and antifoaming agents as necessary, and drying. A method for producing permalloy core is described in claim 5.

In particular, with regard to improving adhesion, considerable frictional force actually acts on the permalloy ribbon surface during the slinting process, punching process, and bending/drawing process line, which may cause the coating to peel off. It is valid in some cases. It is preferable that the binder has as little organic component as possible and has been developed for ceramics, and the amount added is preferably the minimum necessary amount. If a large amount of Ni is mixed in, the viscosity will increase and the coating properties will be deteriorated, and the Ni
-Organic components may be mixed into Fe as impurities and deteriorate magnetism, which is not preferable. Specific examples of the binder include acrylic ester copolymer resin whose main component is water-soluble emuldigone type, or ethylene-vinyl acetate copolymer resin, but it is limited to these as long as it has the above-mentioned effects. It's not something you do.

Generally, water-Mg(OH)z or water-Mg(
OH) zIf only a small amount of binder is added to MgO slurry, the solid content in the slurry, Mg
(OH) z , MgO, etc. may precipitate in the solution, which may impair coating properties. In this case, by adding a small amount of thickener, the viscosity of the slurry can be maintained at an appropriate level, and this drawback can be greatly improved.

However, adding too much thickener will gel the slurry and
It should be used in an appropriate amount as it will significantly impair the applicability.

Specific examples of the thickener include those having a smectite structure containing 5ift as a main component, but the thickener is not limited thereto as long as it has the above-mentioned effects.

Additionally, when the above-mentioned binder is added, the coating solution tends to foam (and the coating properties tend to be impaired).In contrast, the problem can be solved by adding a very small amount of a commercially available antifoaming agent. There are many.

By the way, when applying the above-mentioned coating liquid to wide permalloy, for example, in the process of manufacturing a wound core, it has been common practice to slit the permalloy ribbon to the width of the final product and then immerse the permalloy ribbon in the liquid and dry it. However, with the dipping method, it may not be possible to uniformly obtain a coating film of a predetermined thickness. Therefore, in the method according to claim 4 or 5, the annealing separation coating is applied to the permalloy ribbon by applying a coating solution to the permalloy ribbon using a roll coater or a bar coater, and then drying the coating to a thickness of 0.1 to 50 μm on the ribbon. Preferably 0
．． Claim 6 provides a method for manufacturing a permalloy core, characterized in that the permalloy core is coated with a coating having a thickness of 5 to 10 μm.

Roll coaters or bar coaters, which are known techniques for uniformly applying coatings to thin sheets or foil strips, are also well suited for the purposes of the present invention.

Roll coater method allows plate thickness of 0.1 to 5W! , the bar coater method is more effective in the case of 0.01 to 0.1+s+.

Drying can be done by evaporating the moisture in the applied slurry to make it less sticky, and it is practical to dry it continuously by short-time heating at 100°C.The film thickness is the same as the thickness of the permalloy ribbon. Although it is controlled depending on the purpose, it is possible to achieve a film thickness of 0.1 to 50 μm using a roll coater or bar coater, and for thick materials, the maximum film thickness is 50 μm.
The foil material may be as thin as 0.1 gm, but generally a film thickness of about 0.5 to 10 μm is more practical.

The film with the above film thickness mainly composed of Mg(0)1)z has a solid lubricating ability, so as mentioned earlier, the amount of lubricating oil normally used during slitting, punching, bending, and drawing can be reduced. Or it can be omitted. Therefore, claims 4 to 6
Claim 7 provides a method for manufacturing a permalloy core, characterized in that the supply of lubricating oil is simplified or omitted in the method described in any one of the above.

The simplification and omission of the use of lubricating oil also means the simplification and omission of the oil washing process that is normally performed, and shows that the application effect of the present invention is large.

If the film that makes the above possible is particularly thin, it generally does not significantly impair adhesion even after magnetic annealing, and all or part of the annealing separator can be used as is for the purpose of interlayer insulation resistance. Therefore, in the method according to any one of claims 4 to 7, the production of a permalloy core is characterized in that after magnetic annealing, all or part of the annealing separator attached to the surface is utilized as an interlayer insulation resistance coating. Claim 8
Described in .

According to the method of manufacturing permalloy core according to the present invention, not only production efficiency is greatly improved, but also magnetic properties and
A magnetic core with an excellent space factor can be obtained.

〔Example〕

The present invention will be explained in detail below.

Example I Ni 77.0%, Cu 3.6%, Mo 4.3%,
A wide permalloy PC grade cold-rolled plate coil having a plate thickness of 0.1 m and a plate width of 350 m, consisting of CO, 0.007%, Si 0.4%, Mn 0.6%, and the remainder Fe, was prepared. This wide coil was divided into two types: (a) and (b). (A) is for a conventional process, and a wide coil is slit to form a final width of 10 square coils. This narrow coil (A) and
After degreasing the wide coil (b) with trichlene, it was immersed in a slurry of alumina powder with an average crystal grain size of 0.2 μm and pure water, and then passed through a furnace at 150° C. to dry it. The coating film thickness at that time was approximately 5 μm in both cases, but in the case of the narrow width coil (A), the film thickness varied in the width direction, and at the center it was approximately 5 μm.
．． Although it was 5 to 5.5 μm, the edge was 5 to 15 μm.
Met. On the other hand, in the wide coil (b), 5 at the extreme end.
~15 μm, but in most of the center it was 4.5-5.
It was 5pm. The narrow coil (A) was wound 50 times with an inner diameter of 40 mm to form a total of 30 wound cores, and was subjected to magnetic annealing. The wide coil (b) was cut into 10 width strips using a slitter, and wound 50 times with an inner diameter of 40 mm to obtain a total of 30 wound cores, which were subjected to magnetic annealing. Magnetic annealing of the wound core from the narrow width coil (a) and the wound core from the wide width coil (b) was performed at 1150°C in a dry H2 stream for 30 minutes.

The outer diameter of the wound core was measured in relation to the magnetism and space factor of the wound core thus obtained, and the results were as shown in the table below.

According to the results shown in the table above, it can be seen that by applying the present invention to the production of wound cores, it is possible to obtain products with high and stable magnetic properties and excellent space factors.

Example 2 Ni 79.3%, Mo 5.1%, CO, 003%,
Si 0.33%, Mn 0.9%, SO, 0004
%, PO,002%, NO,0007%, balance Fe
Par 7042 with a board thickness of 0.05m and a board width of 250cm.
After degreasing the 03 grade cold-rolled foil with trichlene, a coating containing magnesium hydroxide as a main component with a thickness of 3 nm was applied to both surfaces of the wide coil coil in the following manner. In other words,
Highly active magnesium hydroxide 1 with an average grain size of 0.1 μm
After putting 50g in pure water 52 and stirring vigorously for about 3030 minutes at room temperature, the main ingredients are a water-soluble emulsion type acrylic ester copolymer resin developed for ceramics as a binder and SiO□ as a thickener. A small amount of a substance having a smectite structure was added, and the mixture was further stirred for 30 minutes. After applying the obtained slurry to the wide coil using a rubber bar coater, the plate was passed through a furnace at 150°C to form a slurry containing Mg (OH) z as the main component,
Moreover, a permalloy coil with an annealing separation coating having excellent adhesion was obtained. After slitting this coil into a final width of 151 widths, a wound core with an inner diameter of 50 threads and a number of turns of 100 was obtained using a high-speed automatic winder. A1. is applied to the side cross section of the obtained core. Magnetic annealing was performed at 1100° C. for 2 hours in a vacuum after sprinkling O and fine powder. The average value of the effective relative magnetic permeability at 1 kHz of a total of 10 wound cores obtained in this way is 4.
It was 7,500.

It should be noted that when the final width of the annealing separator was dipped, applied and dried according to the conventional method, it was impossible to wind it up using a high-speed automatic winding machine because the coating thickness was uneven, but the method according to the present invention I was able to wind it up smoothly without any trouble.

Example 3 Ni 77.5%, Cu 3.4%, Mo 4.4%,
A permalloy PC-grade cold-rolled thin plate wide coil having a thickness of 0.25 mm and a width of 400 mm was prepared, consisting of 0.8% CO, 0.2% Si, 5% MnO, and the remainder Fe. Such wide coils were divided into two types: (A) and (IT).

(A) is for the conventional method, with a wide coil slit to 20cm
The final width of the coil was made. E and I cores are obtained from the coil with a continuous punching machine, and after degreasing with Triclean, an average of 3μ is obtained.
Alumina powder with a diameter of m was applied. Wide coil (b)
Regarding this, the same wide coil was passed through a separately prepared 5 wt % butyl acetate solution bath of Zr(OCdb)a after degreasing with trichlene, and then passed through a drying oven several times to form a 3 μm thick coated coil on the surface. A film was formed.

The coil was slit to a width of 20 mm, and then punched into E and I cores using a continuous punching machine.

The thus obtained cores (a) and (b) each weighing 100 kg were magnetically annealed at 1120° C. for 1 hour in a dry hydrogen stream. The table below shows the time required to manufacture the core (relative comparison from wide-width coil to magnetic annealing) and magnetic results (four frame-shaped test pieces were conveniently punched out from each strip of the final width coil, and the results were calculated after magnetic annealing. These were measured as one set.

Frame-shaped test piece: final width 20×20 including both ends of the coil
The square shape of the cabinet, with a 12sm x 12m hole in the center.
View.

According to the results in the table above, it is clear that the method of the present invention can produce good cores with less variation in a shorter time than the conventional method.

Example 4 Ni 79.5%, Mo 5.00%, CO, 004%
, SiO, 24%MnO, 8%, SO, 0003
%, PO,001%, NO,0005%, balance Fe
A permalloy PC grade 3 cold-rolled thin plate wide coil having a thickness of 0.351 m and a width of 250 Im was prepared. Such wide coils were divided into two types: (a) and (b). The wide coil (A) is made by the conventional method, and the wide coil (A) of Example 3 is made by the conventional method.
Magnetic annealing specimens were obtained using exactly the same method as in case a).

Regarding the wide coil (b), after the wide coil was degreased with cleanser, a coating mainly composed of magnesium hydroxide with a thickness of about 2 μm was applied to both surfaces of the coil in the following manner. In other words, 150g of highly active magnesium hydroxide with an average crystal grain size of 0.1μm was placed in 5Il of pure water1, and after stirring vigorously with a mixer for about 20 minutes at room temperature, water-soluble emulsion type acrylic was used as a binder developed for ceramics. Add a small amount of ester copolymer resin and a smectite structure mainly composed of 5iOz as a thickener, stir for another 30 minutes, and apply the resulting slurry to the wide coil using a rubber roll coater. After that, by passing the plate through a furnace at 250°C, M
An annealing separation coating containing g (OH) z as a main component and having excellent adhesion was applied. The wide coil thus obtained was slit into a final board width of 20 mm using a round tooth slinter, and E and I cores were obtained using a continuous punching machine.

In this case, there was no particular problem even if slitting oil and punching oil were not used, and therefore the degreasing step after punching could be omitted.

E, I cores (a) and (b) obtained in this way are each 100
kg was subjected to magnetic annealing for 3 hours at 1100"C in a vacuum annealing furnace. In the case of (b), even after magnetic annealing, the adhesion of the coating still exists to some extent, so in most cases it was left as is. It could be incorporated into equipment, and essentially functioned as an interlayer insulation resistance film.

The table below lists the measured values obtained by the same method as in Example 3.

From the above description as well as from the table above, the advantages of the present invention are clear.

(Effects of the Invention) As detailed above, according to the permalloy core manufacturing method of the present invention, the conventionally complicated wound cores, E, I cores, etc. can not only be manufactured efficiently (but also the magnetic properties of the product can be improved). Since it is stabilized to a high level, it is of extremely high value industrially.

Claims (8)

[Claims] (1) After slitting a wide permalloy ribbon coated with an annealing separation coating with a film thickness of 0.1 to 50 μm on at least one surface to the final width, winding or punching is performed. A method for producing a permalloy core, characterized by performing magnetic annealing at a temperature of °C. (2) The method for manufacturing a permalloy core according to claim 1, wherein bending or drawing is performed after the winding or punching. (3) The method for producing a permalloy core according to any one of claims 1 to 2, wherein magnetic annealing is performed after applying an annealing separator to the processed sheared surface. (4) Production of the permalloy core according to any one of claims 1 to 3, wherein the main component of the annealing separation coating applied to the surface is magnesium hydroxide (Mg(OH)_2). Method. (5) The annealing separation coating is water, Mg(OH)_
2. A binder, a thickener,
5. The method for producing permalloy core according to claim 4, wherein the permalloy core is obtained by coating and drying a solution containing one or more antifoaming agents. (6) The coating for annealing separation is applied to the permalloy ribbon by a roll coater or bar coater, and then dried to form a coating of 0.1 to 50 μm on the ribbon.
6. The method for producing a permalloy core according to claim 4, wherein the permalloy core is coated with a coating having a thickness of preferably 0.5 to 10 μm. (7) The method for manufacturing a permalloy core according to any one of claims 4 to 6, characterized in that supply of lubricating oil during processing is simplified or omitted. (8) The method for manufacturing a permalloy core according to any one of claims 4 to 7, characterized in that after magnetic annealing, all or part of the annealing separator adhering to the surface is utilized as an interlayer insulation resistance coating.