JPS6328017A - Annealing method for amorphous metal core - Google Patents

Abstract

PURPOSE:To manage a uniform temperature by the heat generation of a core itself, to effectively apply a magnetic field and to economically anneal an amorphous metal core by exciting with a high frequency wave in temperature rising and temperature holding steps during an annealing step, and exciting with a DC in temperature falling step. CONSTITUTION:A coil for generating a magnetic field is excited with a high frequency wave at the time of temperature rising and temperature holding and with a DC at the time of temperature falling. That is, a power source applied to the coil 2 is switched from a high frequency power source 5 to a DC power source 3 at the switching point from the temperature holding step B to the temperature falling step C, and a magnetic domain array is aligned in a direction of a magnetic field generated by the DC excitation in the step C. Thus, it is so regulated as to obtain an annealing temperature within a uniform allowable range by the iron loss generated from the core itself, and a necessary magnetic field force is effectively obtained by the DC excitation at the time of temperature falling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a method for annealing an iron core made of an amorphous metal by performing iron annealing in a magnetic field to obtain long durability.

[Conventional (]) Technology] FIG. 3 is a conceptual diagram of a commonly used method of annealing this type of amorphous metal core. (Fig.) Here, (1) is an amorphous metal core, and (2) is an iron core (for the purpose of generating a magnetic field).
1) is a T coil wound around the coil, (3) is a constant current DC power supply applied to the coil, and (4) is an annealing furnace.

General (The annealing temperature pattern of this amorphous metal is roughly divided into δ as shown in Figure 4, and consists of three steps: temperature raising step A, m degree holding step B, and temperature lowering step C. The permissible set temperature range is a recommended temperature of just under 400'C ±5~
It is characterized by its extremely small temperature of 10°C. The generation of a magnetic field is necessary in the temperature-lowering step C, which has an effect on the formation of magnetic domain alignment.A current is supplied from the DC power source (3) to the coil (2) in FIG. 3.

By the way, annealing furnaces for silicon steel sheet cores have a relatively large allowable temperature range if the temperature of the target core is raised above a certain set temperature, and the temperature distribution is rough. Therefore, in many cases, a continuous annealing furnace is adopted, but in the case of an amorphous core, a batch furnace is adopted in order to achieve uniform temperature distribution and one of the characteristics mentioned above. There are an increasing number of cases where this is the case.

[Problems that inventions can solve]

The conventional annealing method requires only one step as described above, and the one-step annealing furnace itself, which performs sufficient temperature control, is not only large and expensive, but also expensive. The working efficiency of rice annealing work is 1. Maf: The coil for magnetic field generation is used only when the temperature is lowered during the annealing process.
One problem is that only the strainer is used, and when the temperature rises, it works in the opposite direction (this also works to absorb the heat inside the furnace).

This invention was made with the aim of solving the above-mentioned problems.It enables sufficient temperature control, is suitable for a continuous furnace type, and has a coil for generating a magnetic field. is essential when raising and maintaining temperature, and at the same time ζ
The object of the present invention is to obtain an annealing method in which it is difficult to apply a shielding magnetic field when the temperature is lowered.

[Top means to solve problems]

This invention [method for annealing an amorphous metal core] provides a method for supplying power to a magnetic field generating coil to perform high frequency excitation during temperature rise and temperature maintenance (in this case, high frequency excitation, and in order to perform direct current excitation in temperature reduction special program). It's like a T-shirt.

[Effect]

This invention (Kokero annealing method) is a so-called iron loss trowel in which heat is generated from the iron core itself, which is partially energized by high frequency during heating and temperature maintenance, and the annealing temperature is within the allowable range of uniform fC. It is adjusted so that it can be obtained, and when the temperature is lowered, the DC excitation (dc excitation) is effective.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described for one pair. 1st
In the figure, Figure 3 shows the same parts as eyebrows 1 and 1,
, (5) is a single high frequency power source for high frequency excitation.

In Fig. 2 (the annealing temperature pattern of the iron core shown), the shaded area E is set at an arbitrary temperature in the Birch type annealing furnace.
Part 8 shows the heat generation temperature of the L.1 core itself generated by the light frequency excitation a1. Temperature management is controlled by the high frequency excitation of these 7 parts (adjusted in the rolling region, making it possible to adjust in a narrow range of 15 to 10°C.

In the above configuration, at the point of change from the temperature holding step B to the temperature lowering step C, the power applied to the coil (2) is changed from the high frequency (5) to the DC power (3). In the temperature-lowering step C, the magnetic domain is arranged in the direction of the single magnetic field generated by the DC excitation.

In the embodiment, the annealing process is performed in a continuous annealing furnace, and the same effect as in the above embodiment is obtained.

〔Effect of the invention〕

As described above, according to the present invention, high frequency excitation is carried out in the temperature raising and temperature holding steps during the annealing process, and a page flow porcelain filter is used in the temperature cooling process.
Temperature control town f? It is possible to apply an effective magnetic field to the surface of the amorphous metal core regardless of the size of the core, and to economically annealing amorphous metal cores without having to use a large and expensive annealing furnace. It has a calming effect.

[Brief explanation of drawings]

Figure 1 shows the concept of an annealing method for a small amorphous metal core (an embodiment of the present invention), Figure 2 is a schematic diagram of an annealing temperature pattern for a small core of the present invention, and Figure 3 shows a conventional annealing method. The conceptual diagram and FIG. 4 are a schematic diagram of the annealing temperature pattern D) of a conventional iron core. In the figure, (1) is an amorphous metal core, (2) is a coil, (3) is a constant current blood flow current υ, (4) is an annealing furnace, (
5) is a high frequency % source, Q is a temperature raising step, (B) is a temperature holding step, and (C) is a temperature lowering step. In addition, in the figure, the same reference numeral 1 indicates the same part.

Claims (1)

[Claims] In a method for annealing an amorphous metal core, which comprises at least a temperature raising step, a temperature holding step, and a temperature lowering step, and in which the amorphous metal core is annealed in a magnetic field, high-frequency excitation is performed during the temperature raising step and temperature holding step. A method for annealing an amorphous metal core, characterized in that during the temperature lowering step, annealing is performed by supplying power from a power supply device to a coil wound around the amorphous metal core for DC excitation.