JPH0724247B2 - Heat treatment method and apparatus for amorphous alloy ribbon winding core - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat treatment method and apparatus for improving the magnetic properties of an amorphous magnetic alloy ribbon.

<Prior art> When an amorphous alloy ribbon is used for a high frequency transformer, a choke coil, a magnetic filter, etc., use one having magnetic characteristics suitable for them, for example, to increase the magnetic permeability or to make the hysteresis curve square-shaped. Properly lowering the ratio Br / Bs or reducing the core loss is an essential property based on the magnetization generation mechanism. In addition, by controlling the magnetic domain distribution of the alloy by an appropriate method, It is possible to bring out the magnetic characteristics required for the product. As one of the control means, there is an orthogonal magnetic field cooling method.

One of the cooling methods in the orthogonal magnetic field is a heat treatment method in a rotating magnetic field. This is a method of applying the above magnetic field during heat treatment in order to reduce the in-plane induced anisotropy of the magnetic thin film and the ribbon.

However, in this method, two or more pairs of Helmholtz coils or electromagnets are arranged outside the winding core in order to apply a perpendicular or rotating magnetic field, or a method of winding a wire directly on the winding core is adopted. Has been. However, the installation of the Helmholtz coil or the electromagnet requires a space for picking up, and there is a drawback that the winding work is complicated and the heat treatment apparatus for mass production is too complicated.

<Object of the Invention> In order to eliminate the above-mentioned drawbacks, the present invention uses a synthetic magnetic field generated by a circular magnetic field by an energization method based on Ampere's law and a perpendicular magnetic field generated by a solenoid coil that also serves as a winding resistance heating furnace. As a result, by applying a synthetic magnetic field to a large number of wound cores in a small space, a perturbation magnetic field is generated in the ribbon surface, and heat treatment is performed in that to reduce the in-plane induced magnetic anisotropy, making it suitable for mass production. It is to provide a simple heat treatment apparatus in a magnetic field.

<Structure of the Invention> According to the present invention, a wire is passed through a hollow portion of a ribbon winding core made of an amorphous alloy extending in a uniaxial direction, and the wire is energized to feed the current to the ribbon winding core. In a direction perpendicular to the circular magnetic field applied to the ribbon winding core and the winding coil for heating the ribbon winding core provided outside the ribbon winding core to cover the ribbon winding core. A heat treatment method for an amorphous alloy ribbon winding core is provided, in which the ribbon winding core is heat treated in a synthetic magnetic field synthesized by a right-angle heating magnetic field applied in the width direction of the ribbon winding core. To be

Further, according to the present invention, a magnetic core mounting portion for mounting a ribbon winding magnetic core made of an amorphous alloy extending in a uniaxial direction, and a conductor mounting portion for providing a conductive wire in a hollow portion of the ribbon winding magnetic core, A winding resistance furnace for mounting the winding coil for heating the ribbon winding core on the outer side of the ribbon winding core, and an energizing means for energizing the conductor, and further energizing The means is a circular magnetic field applied along the uniaxial direction to the ribbon winding core when the wire is energized, and a direction perpendicular to the uniaxial direction from the winding wire ring when energizing the winding resistance furnace.
An amorphous alloy ribbon winding core that heats the ribbon winding core by generating a synthesis magnetic field synthesized by the orthogonal heating magnetic field applied in the width direction of the ribbon winding core, and heat treating the ribbon winding core in the synthesis magnetic field. A heat treatment apparatus is obtained.

<Operation> In the heat treatment method for an amorphous alloy ribbon winding core according to the present invention, it is generated along the axial direction of the winding core by energizing the conductor wire provided in the hollow portion of the ribbon winding core (winding core). Heat treatment is carried out in a synthetic magnetic field consisting of a circular magnetic field and a perpendicular heating magnetic field generated in a direction perpendicular to the circular magnetic field from a coil wound around the winding core to cover the winding core and heat the winding core. ing.

When the conducting wire is passed through the winding resistance core at the center of the winding resistance furnace and the conducting wire and the winding resistance furnace are simultaneously energized, a magnetic field can be applied simultaneously in the width direction of the winding core and in the direction perpendicular thereto to obtain a composite magnetic field. . At the same time, the wound core can be heated at a constant temperature.

At this time, the synthetic magnetic field at an arbitrary point P applied to the winding core Is given by

Here, x is the distance from the center of the wire-wound resistance furnace to point P, l is the length of the wire-wound resistance furnace, a is its radius, and N and i are the number of windings and the current, respectively.

On the other hand, when i is passed through the winding resistor, the heating temperature ΔT of the resistor is given by the following equation.

Where ρo is the specific resistance of the winding resistor, t is the time, J is the work equivalent, Cp is the specific heat, and d is the density. As is clear from equation (2), in equation (1) The diameter D of the winding may be controlled in order to generate heat at an arbitrary temperature without changing the temperature.

Using the above equipment, the crystallization temperature Tx of the amorphous alloy ribbon was measured.
The magnetic history curve can be changed by performing appropriate heat treatment in a magnetic field below.

For example, the residual magnetic flux density Br of the amorphous alloy ribbon can be appropriately reduced and the squareness ratio Br / Bs can be controlled by applying a synthetic magnetic field of two directions as described above and performing heat treatment. I can. The applied magnetic field may be AC or DC. An applied magnetic field of 10 Oe is sufficient to saturate the magnetization of the ribbon.

By performing the heat treatment as described above and appropriately reducing Br / Bs, it is possible to obtain the characteristics required for a magnetic core material such as a high frequency transformer and a smooth choke coil.

<Examples> Examples are given below to describe in detail the method and apparatus for heat treatment of an amorphous alloy ribbon winding core of the present invention with reference to the drawings.

First, the outline of the heat treatment method for the amorphous alloy ribbon winding core of the present invention will be briefly described. This heat treatment method consists of a circular magnetic field applied along the uniaxial direction to the ribbon winding core by energizing the wire through the hollow portion of the ribbon winding core made of an amorphous alloy extending in the uniaxial direction. , The width of the ribbon winding core being perpendicular to the uniaxial direction from the winding coil for heating the ribbon winding core provided outside the ribbon winding core. The ribbon winding core is heat-treated in a synthetic magnetic field synthesized by a perpendicular heating magnetic field applied in the direction. According to this heat treatment method, the in-plane induced magnetic anisotropy can be reduced during the heat treatment of the ribbon coil core.

FIG. 1 is a side view showing a main configuration of a heat treatment apparatus for an amorphous alloy ribbon winding core according to an embodiment of the present invention, in which this heat treatment method is introduced.

In this heat treatment equipment, one end side of the equipment mount 11
A branch pipe for inhaling N ₂ gas or Ar gas is provided,
In addition, the other end is housed in the device mounting base 11 so that the device mounting base 11
An atmosphere gas introduction pipe 12 is attached so that N ₂ gas and Ar gas can be discharged inside. A copper pipe 1 as a conducting wire is inserted into the atmosphere gas introducing pipe 12, and a winding core sample 4 as a thin ribbon magnetic core made of an amorphous alloy extending in a uniaxial direction is provided outside the atmosphere gas introducing pipe 12. It is attached by a sample pedestal 5 and a screw 9 provided in the winding resistance furnace. A coil 8 which is a wound wire ring for generating a heat generation magnetic field is attached to the outside of the wire-wound resistance furnace. It is fixed by a gas sealing plug 6 provided. A thermocouple 2 is provided in a part of the gas sealing plug 6 at this one end side, and the gas sealing plug 6 at the other end side is for fixing the atmospheric gas introduction pipe 12 and the wire resistance furnace on the device mounting base 11. It is a fixed part. A water cooling pipe 7 for inflowing and outflowing cooling water is attached outside the winding resistance furnace, and an auxiliary magnetic field generating coil 3 is provided outside the water cooling pipe 7. The auxiliary magnetic field generating coil 3 and the water cooling pipe 7 are provided on the apparatus mounting base 11 for the heat treatment mounting base 10.
Is fixed to the winding resistance furnace by.

In this heat treatment apparatus, the outer wall of the atmosphere gas introduction pipe 12 serves as a magnetic core mounting portion for attaching the winding core sample 4 as a thin ribbon magnetic core, and the plug provided on the inner wall on one end side of the atmosphere gas introduction pipe 12 is the winding core. It serves as a lead wire mounting portion for providing the copper pipe 1 as a lead wire in the hollow portion of the sample 4. Further, this heat treatment apparatus includes an energizing means (not shown) for energizing the copper pipe 1 and the wire-wound resistance furnace. This energizing means applies an axial direction to the winding core sample 4 when energizing the copper pipe 1. Generates a synthetic magnetic field synthesized by a circular magnetic field applied along the coil 8 and a perpendicular magnetic field applied in the width direction of the wound core sample 4 in a direction perpendicular to the axial direction of the coil 8. It works so that the wound core sample 4 is heat-treated in this synthetic magnetic field.

Therefore, the results of the heat treatment of the present invention will be specifically described below, including the method for manufacturing the core sample.

An amorphous magnetic alloy ribbon having a composition of Fe ₉₂ B ₃ Si ₅ and a thickness of 24 μm and a width of 5 mm was prepared by the single roll method. The crystallization temperature Tx of this alloy ribbon was 550 ° C and the Curie temperature Tc was 415 ° C.
This ribbon was wound into a cylinder with an outer diameter of 18 mm and an inner diameter of 12 mm, and this was used as the magnetic core.

The magnetic hysteresis curve was measured using the sample heat-treated under the following heat-treatment conditions. All heat treatments were performed in N ₂ atmosphere. i Untreated, ii 50 after heating at 450 ℃ for 1 hour
Cool to 200 ℃ at a cooling rate of ℃ / min, then
After holding for a period of time, the furnace was cooled to room temperature. During the above heat treatment, 450
At ℃, AC magnetic field is applied in the width direction of the winding core. At 200 ° C, 30 Oe was applied. Also, at 200 ° C in the longitudinal direction of the ribbon DC magnetic field was applied.

The heat treatment state as described above Is displayed. The same shall apply hereinafter.

The magnetic hysteresis curve at DC of the sample subjected to the above heat treatment was measured. FIG. 2 also shows the measurement results of the unheated sample, and FIG. 3 also shows the measurement results of the samples subjected to the three different heat treatments, and Table 1 is a table summarizing the above results.

As is clear from the figure, when the heat treatment is performed using the apparatus of the present invention, the hysteresis curve of the amorphous alloy can be arbitrarily changed. Magnetic field in plate width direction When added, Hc will be slightly increased, but Br / Bs can be significantly reduced. The above magnetic characteristics are high frequency transformer,
Required for smooth choke coil design.

<Effects of the Invention> As described above, according to the heat treatment method for the amorphous alloy ribbon winding core of the present invention, the synthetic magnetic field can be applied in any direction by adjusting the circular magnetic field and the orthogonal heating magnetic field. ，
By reducing the in-plane induced magnetic anisotropy, it becomes possible to rationally perform heat treatment suitable for mass production. Also, in the case of the heat treatment apparatus in which this heat treatment method is introduced, since the respective parts are concentrically arranged along the winding resistance furnace, the structure can be made simple and small.

[Brief description of drawings]

FIG. 1 shows a schematic cross-sectional view of a main part of a heat treatment apparatus for an amorphous alloy ribbon winding magnetic core of the present invention. FIG. 2 shows a magnetic hysteresis curve (A) measured for an unheated sample of an Fe ₉₂ B ₅ Si ₇ type amorphous alloy ribbon produced by the single roll method. FIG. 3 shows the magnetic hysteresis curves of the samples that have been subjected to heat treatment with different applied magnetic fields. 1 …… Copper pipe for generating circular magnetic field, 2 …… Thermocouple, 3 …… Auxiliary magnetic field generating coil, 4 …… Wind core sample, 5 …… Sample holder, 6 …… Gas sealing plug, 7… … Water cooling pipe, 8 …… heat treatment furnace and magnetic field generation coil, 9 …… screw, 10 …… heat treatment furnace mount, 11 …… equipment mount, 12 …… atmosphere gas introduction pipe.

Claims (2)

[Claims] 1. A uniaxially extending thin ribbon magnetic core is applied along the uniaxial direction to the thin ribbon winding magnetic core by passing an electric current through the hollow conductor of the thin ribbon winding magnetic core. A circular magnetic field, and a direction perpendicular to the uniaxial direction from a winding wire ring for heating the ribbon winding core provided outside the ribbon winding core and covering the ribbon winding core, and A heat treatment method for an amorphous alloy ribbon winding core, characterized in that the ribbon winding core is heat-treated in a synthetic magnetic field synthesized by a right angle heating magnetic field applied in the width direction of the ribbon winding core. 2. A magnetic core mounting portion for mounting a ribbon winding magnetic core made of an amorphous alloy extending in a uniaxial direction, a conductor mounting portion for providing a conductor in a hollow portion of the ribbon winding magnetic core, A winding resistance furnace for mounting the winding coil for heating the ribbon winding core on the outer side of the ribbon winding core, and an energizing means for energizing the conductor, further comprising: The energizing means includes a circular magnetic field that is applied to the thin ribbon winding core along the uniaxial direction by energizing the conducting wire,
A combined magnetic field is generated by energizing the winding resistance furnace from the winding wire in a direction perpendicular to the uniaxial direction and with a perpendicular heating magnetic field applied in the width direction of the ribbon winding core. A heat treatment device for an amorphous alloy ribbon winding core, which is generated and heat-treated in the synthetic magnetic field.