JPS6110212A - Characteristic improvement of amorphous alloy thin band - Google Patents

Abstract

PURPOSE:To improve an iron loss without deterioration of space factor by applying insulating coat of an inorganic oxide consisting of at least one from among SiO2, Al2O3 and MgO on an amorphous alloy thin band by ion plating. CONSTITUTION:An insulating coat consisting of at least one from among SiO2, Al2O3 and MgO is applied to the surface of an amorphous alloy thin band, which is used for an iron core material for laminated or wound transformer by ion plating. It is appropriate that mean film thickness of an inorganic oxide is 0.01-0.5mum. Thus, the insulating material of the inorganic oxide can be coated with ion plating without heating the amorphous alloy thin band, thereby the insulating coat can be formed without embrittlement and crystallization of the amorphous alloy thin band by itself.

Description

[Detailed description of the invention] (Technical field) Iron core for laminated or wound transformers (hereinafter simply referred to as core)
4?Amorphous alloy ribbon used for material? Note: The technical contents described in this specification regarding improvements are proposed in Development Results 1 regarding the suitability of the insulating coating applied to the surface of the ribbon.

(Background technology) When molten alloys such as Fe-B-based and Fe-B-8i-based alloys are rapidly solidified at a cooling rate of about 105 to NO'°C/sec, a plate with a thickness of about 20 to 50 μm with a disordered atomic arrangement is formed. An amorphous alloy ribbon is obtained.

Such amorphous alloy ribbons have excellent soft magnetism and especially extremely low core loss, and are therefore attracting attention as a potential competitive material to grain-oriented silicon steel sheets currently used as core materials.

Conventionally, this amorphous alloy ribbon was not coated with an insulating coating.
It was customary to use the bare core in nine-core assembly transformers, etc., and the reason for this was that an appropriate insulating coating had not been developed, but the cylindrical resistivity of the amorphous alloy itself and the thin strip's This is because the surface roughness is large, so when laminated, the interlayer resistance is relatively high, and the influence of eddy current loss on the total loss is small.

(Problem) However, with recent advances in manufacturing technology for amorphous alloy ribbons, the surface has become smoother and the space factor has improved.
Interlayer resistance tends to decrease and eddy current loss increases when processed into a core.

Therefore, it is desired to reduce the eddy current loss, or in other words, the total iron loss, without reducing the space factor of the amorphous alloy ribbon.

By the way, JP-A-58-109171 proposes applying an electron beam curable resin coating to avoid embrittlement of the amorphous alloy ribbon due to heating. However, as is well known, for example, the i of Fe-B-Si amorphous alloy is
In order to make full use of this property, it is necessary to perform annealing in a magnetic field at 350° to 400°C, but the former organic resin carbonizes during this annealing and maintains the desired interlayer resistance. Can not do it.

On the other hand, the insulation coating for conventional silicon steel sheets takes 40"
Since heating exceeding C is required, it causes embrittlement, crystallization, etc. of the amorphous alloy, and it cannot be used as an insulating coating for an amorphous alloy ribbon.

(Motivation for the invention) Recently, Ti has been used for the purpose of extending the life of press dies and cutting tools.
Ion blating of Nl and Kogamonobo has been attempted and high adhesion and good wear resistance have been reported. When this coating technique was applied to surface treatment for improving the amorphous alloy ribbon, excellent performance was obtained as will be described later, leading to the success of this invention.

(Objective of the Invention) The present invention is based on the results of research and development on insulating coatings suitable for amorphous alloy ribbons and means for forming the same. The object is to advantageously compensate for the decrease in glabellar resistance resulting from smoothing without deteriorating the space factor of the gold or amorphous alloy ribbon.

(Structure of the Invention) This invention provides a 5in2°A4.08
This is a method for improving the characteristics of an amorphous alloy ribbon, characterized in that an insulating coating of an inorganic oxide consisting of at least one of MgO and MgO is applied by ion blasting.

Here, the average film thickness of the insulating film 'i 0.01 to 0.5
According to the present invention, the amorphous alloy ribbon can be
Ion blating is used which can coat an inorganic oxide insulating material made of at least one of in, AJ, O, and MgO.

In the ion blating method, in a reduced pressure inert gas atmosphere of about 10 tOrr, a glow discharge metal is applied to the coating target as a cathode, and the evaporated substances are ionized and accelerated as they pass through the glow discharge, causing them to grow on the target surface. At the same time, sputtering is performed on the target surface using ionized inert gas particles, making it possible to form a film with much better adhesion than normal vacuum deposition at an extremely high speed using electron beam heating. I can do it.

Incidentally, even if a film with good adhesion can be formed by the so-called sputtering method, it has the disadvantage that the growth rate of the film is slow and productivity is poor.

As mentioned above, in this invention, the heating of the amorphous alloy ribbon is not sufficient, so when trying to simply transfer the insulation coating baking for silicon steel sheets mentioned above, the problem arises because the amorphous alloy ribbon itself is heated. Insulating coatings can be applied without embrittlement or crystallization.

The average thickness of the insulating coating is 0.01 to 0.5 μm, which is suitable because the amorphous alloy ribbon is originally extremely thin.
If it is less than 0.5 μm, complete glabellar insulation cannot be ensured, while if it exceeds 0.5 μm'4, it is not preferable from the viewpoint of interlayer insulation, since even if it is a good fit, the space factor will be impaired.

In other words, the thickness of the amorphous alloy ribbon is 20μm to 50μm.
This is because the non-magnetic, excessively large insulating film has a significant effect on reducing the space factor since it is extremely thin like m.

Fe, 8B□. An amorphous alloy ribbon with a width of 5 mm and a thickness of 30 μm was produced by a single roll method by melting an alloy with a composition of S1□2, and then Holi-rolled in a reduced pressure of argon gas at about 10-200 torr.
A low cathode method ion plating film 1 was formed to have a thickness of 0.2 μm. The deposition time was approximately 15 seconds.

The space factor of the untreated ribbon is 81.8%, 5io2
It was 81.2% for the film-covered ribbon, and there was almost no decrease in the space factor due to the insulating film, and of course the film treatment did not cause embrittlement of the amorphous alloy ribbon.

This amorphous alloy ribbon coated with an insulating film was coated with a diameter of 6 cIn.
As a toroidal core, under a magnetic field of 200 A/m,
370'' was annealed for 0.1 hour and then cooled.

The iron loss of this toroidal core at 50 Hz and 1.8 T was 15 o U, o, 1 o WAc9, which was higher than that of the untreated amorphous alloy ribbon, which was o, 15 W/4 I. It was excellent.

Furthermore, due to this insulating coating treatment, when immersed in transformer oil for a long time, an improvement in oil resistance was observed, without causing the a-sidedness that occurred in the case of no treatment.

(Example) Example 1 Fe y 8 B 10 with a medium diameter of 2 cm and a thickness of 28 μm
S l □s 0.2 μm thick MgO on amorphous alloy ribbon
An insulating coating was applied using ion grape ink. The space factor was 80.7%, and the iron loss W1a/so after annealing in a magnetic field was 0.12 WAg.

Example 2 Example 1 except that the insulating coating was 0.1 μm thick Syu0□
processed in the same way. Occupancy rate is 80.8%, Wla/66
was 0.12 W/Icg.

Comparative Example 1 When the same measurements were performed on the amorphous alloy ribbon used in Example 1 without applying an insulating coating, the space factor was 80.8%.
W z s/s o was 0, 16 W%cy.

(Effects of the Invention) According to the present invention, the amorphous alloy ribbon itself is advantageously adapted to consist of a significantly thin layer, and the core loss is significantly improved without actually inhibiting its space factor. You can take revenge.

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Claims (1)

[Claims] 1. SiO_2, Al_2O_3 on the surface of an amorphous alloy ribbon used as a core material for laminated or wound transformers.
A method for improving the properties of an amorphous alloy ribbon, comprising applying an insulating coating of an inorganic oxide consisting of at least one of MgO and MgO by ion blasting. 2. The method according to claim 1, wherein the average thickness of the insulating coating is 0.01 to 0.5 μm.