JPS5923823A - Improving device for magnetic characteristic of electrical steel sheet - Google Patents

Abstract

PURPOSE:To provide a titled improving device for magnetic characteristics which provides improved productivity by providing an optical system which generates alternately pulse laser light from twi units of laser oscillators, and scans and irradiates the surface of a steel sheet at a specific oscillation frequency. CONSTITUTION:Pulses of an oscillation frequency 2f are oscillated from a master synchronizing pulse circuit 5, and the pulses are alternately used to trigger laser devices 2 and 2'. The laser light of a frequency (f) are oscillated from the devices 2, 2' according to the trigger pulses. The laser light is respectively split by a beam splitter 6 and the one of the transmitted and reflected laser light is made incident to a scanner S. The other is made incident to a scanner S' via a reflecting mirror 7. A steel sheet 1 is thus scanned by the pulses of the frequency 2f at a width w.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for modifying the iron loss value of electrical steel 4tQ.

In the past, numerous means and methods have been proposed for improving the iron loss value of electrical steel sheets. The present inventors focused on the fact that by irradiating a magnetic steel sheet with laser light, the magnetic domains are subdivided and the iron loss value of the magnetic steel sheet is improved.
In No. 18566, the directional electromagnetic force of finish annealing ≦1j
We proposed a method of irradiating the I1.1Jyi surface with laser light. Furthermore, in Japanese Utility Model Application No. 56-123855, an apparatus embodying the above method was proposed.

The present invention relates to a laser irradiation device that further improves the above proposal.

As is well known, grain-oriented electrical steel sheets, for example, crystallographically (11
O) The (110) plane of each crystal grain in the plate, which is displayed as a [001] structure, is in 11 rows on the plate surface.

This method takes advantage of the fact that the axis of easy magnetization [001] is in 11 rows (in the rolling direction), and its production requires extremely strict process control. applied to those formed. The present invention is not only applicable to the above-mentioned manufacturing process, but also
It can also be used for both purposes when assembling into products such as transformers. Size/ko.

The present invention is a particularly effective method when the steel plate to be irradiated with laser is moving.

[Delta] According to the invention, the laser beam is adjusted so that it is focused on the electromagnetic steel plate surface JM from the laser excavation device through the scanning unit and the focusing unit. In addition, the laser beam has two
Split by a beam splitter. The laser beam is
It is irradiated in a direction perpendicular to the rolling direction of the steel plate (hereinafter referred to as the FC direction).

The present invention will now be explained in detail with reference to the drawings.

Figures (a) and (b) are irradiated steel plate 1.
This is a schematic diagram showing a pattern of laser irradiation in the C direction. In (a), the irradiation is performed in a curved shape substantially perpendicular to the rolling direction (L direction), and in (b), the irradiation is performed in a sinusoidal shape. All of these methods are effective methods for generating magnetic domain refining by laser irradiation. By a scanning irradiation optical system as shown in Figure 2, a laser beam from a laser oscillator 2 is transmitted through a scanning irradiation optical system (comprised of a galvano mirror 3, a lens 4, etc.) to the width w of the steel plate 1.
Assume that the laser is irradiated over (cyn). The moving speed of the steel plate in the rolling direction is ・C/5 (IC) 1
The moving distance of the steel plate between time points (δcc) is 1 (ctn
) then! t=-(ln holds true.The oscillation frequency f(H7) is applied to IHJ at this time.
Since the width l is scanned and irradiated with a spot interval a (an), w/lL t = - (2) As shown in Fig. 2, a reciprocating vibrating mirror (galvano mirror)
3 and its vibration frequency is fm (JJz), the following equation holds true.

1(3) 21m From equations (1) to (3), the following relational expression is established between the specifications: 1゛1. One.

That is, in scanning, the width W must be selected so as to satisfy the relationship of equation (4). The only way is to increase line speed υ, increase d:f, or narrow ul. However, the oscillation frequency f of the laser cannot be increased beyond the limit, and as technology advances, the limit will increase.

-; Since it is not possible to make the frequency of Jl higher than fo, the only way to make V faster is to narrow 4. On the contrary II
), it is necessary to slow down ν.

The present invention relates to a device that overcomes these circumstances.

31st: Zl is the laser device 2.2' with oscillation frequency f
(Using +-2 units, each laser beam is sent through a total reflection mirror 3.3' to a scanning device tS,
The beam enters S' and each scans and irradiates the width W. J↓ indicates "7". At this time, W is limited to 11" from the relationship of equation (4). This was the one-sawa area obtained by conventional scanning.

No. 41×1 shows the configuration of the device of the present invention.

Oscillation frequency 2f from master synchro pulse circuit 5
The even-numbered and odd-numbered pulses are used to trigger separate laser devices 2 and 2', respectively, and each laser device 2 is activated according to this trigger pulse.
．． A laser beam of frequency f is oscillated from 2'. These laser beams are split into beam splitters (6) and (1), and are transmitted and reflected (7).
One of the laser beams is immediately incident on the scanning device S, and the other is incident on the scanning device S' via a total reflection mirror, and the laser beam can be converted into a pulse with a frequency of 2f and scanned with a width u) of A2. can.

Therefore, according to equation (5), the -line speed υ can be doubled compared to when scanning the same width V as in the configuration shown in FIG. Also, if υ is kept the same, the scanning width can be doubled.

FIG. 5 shows the logic of the configuration of the present invention. As described above, the present invention makes it possible to achieve twice the line speed or to perform twice the scanning with one defect, using the same number of laser oscillators as in the conventional method. Productivity reform i6. ``People make a significant contribution to ``.

So far, I have explained about pulsed lasers.

A similar effect can be seen even when the laser is continuous wave. In other words, in the configuration shown in Figure 6, 2゜2' is a continuous wave laser, and when two lasers 2.2' oscillate continuously, in the configuration shown in Figure 3, two lasers oscillate continuously, and both have the same output. Comparing the case where power is oscillated, in the case of FIG. 6, it is possible to scan the same width W at twice the line speed. Of course - in this case the master synchropulse circuit is not needed.

The present invention is applicable to both pulse oscillation and continuous oscillation, and CO2. YAK, excimer, 1j2 or C
Any O-curved laser can be applied.

δ(indicates an implementation ``flJ'' demonstrating the effect of the present invention.

Example 1 A grain-oriented electromagnetic steel sheet with a finish annealing width of 2u) = 160 mIn running in the two-stretching direction was irradiated with a conventional laser irradiation device shown in FIG. 3 and a laser having the configuration of the present invention shown in FIG. We attempted an irradiation experiment using an irradiation device.

Two laser oscillators JI+ (The device was a YAG/laser plate each oscillation frequency = 20 K+-1z. J!-5mm,

When scanning irradiation was performed so that O = 0.3 m, the line speed υ at which the same iron loss reduction effect was obtained was determined, and with the configuration shown in Figure 3, the line speed was -25 m/min: 42
an/Se(:+ 7・-51m in the configuration shown in Figure 4)
/mj, n-=85 an/SeC.

These values are expressed as f in the configuration shown in Figure 3 in equation (5).
= 20 x 103H7, in the configuration shown in Figure 4, f.
= /1. This corresponds to an oscillation frequency approximately equivalent to OX 10'' H2, and the effect of this method is clear.

Example 2 A two-annealed cross-sectional electrical steel sheet having a width of 2177 = 16 Q mm running in the rolling direction was exposed to the conventional laser irradiation device shown in FIG. 3 and the present invention shown in FIG. 6. Irradiation experiments were conducted using a laser irradiation device consisting of:

The two laser oscillators are GO□ laser continuous oscillations,
The output per unit was 200 Wa, tt.

When scanning 11G so that the distance is 1--5 mm, the line speed υ at which the same iron 1j4 reduction effect was obtained was determined. 1, 1Ji - In the configuration shown in Figure 3, v = 20
In the configuration of the present invention shown in FIG. 6, a force of 2I-41 m/mjn km 8 cTn/Sec was obtained.

As explained above, according to the present invention, laser irradiation can be performed efficiently.

[Brief explanation of the drawing]

11*l (a) (b) are schematic diagrams showing the laser irradiation pattern, Figure 2 is an explanatory diagram showing the outline of the laser scanning irradiation optical system - Figure 3 is the conventional laser I) < 1
An explanatory diagram of the shooting device, FIG. 4 shows the structure of the device of the present invention.
5 is an explanatory diagram showing the logic of the configuration of the device of the present invention, and FIG. 6 is an explanatory diagram of the device of the present invention when a continuous wave laser is used. ;g, 2': Laser device 3.3': Total reflection mirror 6, beam splitter = 133 Figure 7 (θ) (b) 2nd pole 3 times

Claims (1)

[Claims] Pulsed laser beams are alternately generated from two laser oscillators with a high frequency fl-1z, and pulsed laser beams are generated from a plurality of beam splitters, a total reflection mirror, and a scanning mechanism. 2fHz on the steel plate surface by the optical system consisting of
An apparatus for improving the magnetic properties of a oriented electrical steel sheet, characterized in that scanning irradiation is performed at an oscillation frequency of . 2. An apparatus for improving magnetic properties of an electrical steel sheet according to claim 1, characterized in that an output laser beam from a laser oscillator is continuously oscillated.