JPS5927507A - Annealing method for transformer core using amorphous alloy ribbon - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of annealing a trans iron core using an amorphous alloy ribbon.

It has been evaluated as the most suitable method for manufacturing thin strips of [Hiro I+].
・Ru.

There is a maximum limit of tB for the thickness of the ribbon manufactured by this method, for example, Fe-B-8i-
In the C system, only extremely thin materials of at most a few + It m can be used as electromagnetic restraints. Furthermore, annealing at a relatively low temperature, especially in a magnetic field, is necessary to alleviate the strain introduced during the quenching process during manufacturing and the process of processing the rolled iron core, and to exhibit the original excellent electromagnetic properties. However, the annealing conditions are very strict.

- An example is shown in FIG.

FIG. 1 is a graph showing the relationship between annealing temperature and core value when an iron core made of an amorphous alloy ribbon is annealed in a magnetic field for 15 minutes. That is, when the annealing temperature is 380°C, the iron loss W 13150 (
W/Kg) JJ" exhibits a quadratic curve-like tendency that shows the lowest value, so strict control of the annealing temperature is required in order to obtain the lowest iron loss value.

In the normal annealing process for wound iron cores made of amorphous alloy ribbons,
Heated in a gas or electric furnace. As the size of the iron core increases, it takes a longer time for the internal temperature to rise, making it difficult to reach a uniform temperature. Therefore, with large iron cores, only a small portion of the entire iron core can be annealed under optimal conditions.
The characteristics of the transformer are not as good as expected, and as a result, the range of application of amorphous electromagnetic materials with excellent characteristics is extremely limited to small-sized devices.

The present invention solves this problem.

The gist of this method is to stack copper foils at predetermined intervals between laminated thin strips, pull them out to the outside of the thin strip iron core, heat them with electricity as electrodes, and raise the annealing temperature to a predetermined annealing temperature.

The present invention will be explained below with reference to the drawings. When winding a thin ribbon to make a wound iron core S, after winding a predetermined length, a copper foil that will become an electrode is inserted into the primary P-1. P-2, P-3, P
-4 and the tip of the laying sound. Two pieces of copper foil exposed outside the iron core are used as a pair of electrodes, and a current is passed through the thin ribbon between them, generating resistance heat.

According to such a heating method of the present invention, since heating is performed directly from inside the iron core without using a long heat transfer process, a predetermined annealing temperature can be uniformly reached within a required time.

As a result, the electromagnetic properties of the iron core are improved, and there are significant industrial effects, such as the ability to design designs that eliminate size constraints.

Example 1 A thin strip of 50 long width x 2000 pn (50K9) with an outer diameter of 300 g and an inner diameter of 100 V was made, and 4 pieces of copper foil were placed in equal parts, and the copper foil was crimped on the outer and inner surfaces to form 6 electrodes. During manufacturing, electricity was applied at 300 V and 30 A for about 3 minutes, and magnetic field annealing was performed at 380° C. for 15 minutes. The iron loss was 5% higher than the theoretical value, and the characteristics were good.

[Brief explanation of drawings]

Figure 1 shows the annealing temperature (℃) and iron loss W of the amorphous alloy ribbon core.
15150 (W/N, ), FIG. 2 is a schematic explanatory diagram showing an embodiment of the present invention.

Claims (1)

[Claims] A transformer iron core using an amorphous alloy ribbon is characterized in that a plurality of electrode plates are inserted at predetermined positions between the laminated ribbons, and the laminated ribbons are heated by applying electricity to the electrode plates. Annealing method.