JPS6049697B2 - Method for manufacturing thin metal sheets - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to obtain a metal thin film containing iron as a main component in which crystal grains have grown well without undergoing a rolling process.

The thickness of conventional electric iron plates is 0.3 to 0.5Tn! n low carbon steel plates and steel plates with silicon content of 3% or less are used.

In both cases, a steel ingot is hot-rolled and then cold-rolled, requiring large-scale rolling equipment and intermediate processes such as multiple rolling steps, resulting in high costs. . Furthermore, if the silicon content exceeds 3%, the hardness increases and it becomes difficult to obtain a large rolling ratio, so there are restrictions on the composition from the manufacturing standpoint. However, it is known that if a final heat treatment is performed after cold rolling, crystal grains will grow in a direction that provides good magnetic properties. On the other hand, Fe-B
-M (iron-boron-metal) (M=C, 5i1P1Ge)
There is an amorphous magnetic material with a plate thickness of about 50 μm and the like.

In order to produce this amorphous magnetic material,
There are many restrictions such as cooling rate and composition of molten metal,
It is difficult to manufacture large width and thick plates. In addition, when heat treatment is performed to remove distortion, it must be performed at a temperature that does not cause recrystallization, resulting in a long treatment time.
The disadvantage is that distortion cannot be completely removed. As mentioned above, the conventional method of manufacturing electric iron plates has many problems. The present invention is intended to improve these drawbacks, and will be described below with reference to the drawings.

As shown in FIG. 1, a molten metal 1 of a predetermined composition mainly composed of iron is continuously blown onto a roller 2 using the pressure of an inert gas such as argon gas and cooled to form a thin metal plate 3.
shall be.

By adjusting the spray amount of molten metal 1 and the rotational speed of roller 2, a predetermined plate thickness is obtained. Further, as shown in FIG. 2, the molten metal 1 can be continuously blown between two rollers 4, and the thin metal plate 5 can be obtained by cooling and rolling at the same time. The method shown in FIG. 2 allows the plate thickness to be determined more accurately than the method shown in FIG. 1, and the cooling conditions are more uniform. At this time, even if an amorphous portion is included in the five-metal thin plate due to conditions such as composition and cooling rate, it will not be a problem as long as a metal thin plate with predetermined characteristics can be obtained by the method of the present invention. The main purpose here is to make a thin metal body with a predetermined thickness. rollers 2, 4
In order to achieve the desired thickness, copper and other metals such as copper and other metals, alumina, etc., which have poorer thermal conductivity than metals, and ceramics are recommended. can be used.

In addition, the surfaces of the rollers 2 and 4 are smooth surfaces, and when cooling the thin metal body, a non-oxidizing atmosphere is created using an inert gas atmosphere such as argon gas or a vacuum atmosphere, and the temperature of the rollers is controlled. is desirable for producing thin metal sheets with stable and constant properties. The metal sheet thus obtained has non-uniform strain, small crystal grains, and contains amorphous parts, so it does not exhibit good magnetic properties and has little utility as an electric steel sheet. When a thin metal sheet containing a large amount of alpha iron, which is a ferromagnetic material, is annealed at a temperature above the recrystallization temperature to remove strain and cause grain growth, its magnetic properties are improved and its utility as an electric iron sheet increases.

Naturally, even if amorphous components are included, they will be crystallized, and if the above heat treatment is performed after applying a skin bath to flatten and introduce distortion, not only will grain growth be promoted, but the skin will be Recrystallization occurs so that the direction of easy magnetization is in the direction of the bus, and the effect of improving magnetic properties is significant. Furthermore, if decarburization annealing is performed as a heat treatment, as is well known, the effect of improving magnetic properties is significant due to effects such as promotion of crystal grain growth. And since the metal thin plate obtained by the rapid cooling method contains γ iron, which is non-magnetic,
If heat treatment is performed at a temperature above the entry point where the γ iron content is changed to α iron content, the magnetic properties will be improved. By appropriately combining the above three heat treatments and skin bath processes, it is possible to obtain good magnetic properties as an electric iron plate. Next, examples will be shown.

Example 13 The composition of the metal thin plate before treatment was Fe: 97%, Si: 3%,
Other impurities: Trace amounts.

Metal thin plate? α-iron annealed plate thickness approx. 0.35 mm, 950°C'', 2 minutes, argon gas,
4 (Skin bath? Recrystallization annealing approx. 4% 800℃, 2 hours, nitrogen gas, magnetic waiting room: Wl5/60=8W/Kf, BLO
=15KGa Example 2 Composition of thin metal plate before treatment Fe96
%, Si: 2%, A1: 1%, C: 1%, other impurities: trace amounts.

Metal thin plate? Decarburization annealing? Board thickness approximately 0.

35mTL 800℃, 10 minutes, wet hydrogen gas, mono-α iron annealing? Skin bath 950℃, 2 minutes, argon gas
Approximately 5% recrystallization annealing at 850℃, 2 hours, 10% hydrogen gas, other nitrogen gas, magnetic? Peα卆〆L:Wl5/4
0=7W/K, BLO=15KGa Example 3 Composition of thin metal plate before treatment Fe: 98%, Ci: 1.5%, Mn
:0.

5%, other impurities: trace amounts.

Metal thin plate? Decarburization annealing? Plate thickness approx. 0.35TLTL800℃
, 10 minutes, wet hydrogen gas, alpha iron annealing? skin bath 9
50℃, 2 minutes, argon gas, about 5% ~ decarburization annealing? Recrystallization annealing 800℃, 10 minutes, wet hydrogen gas 8
50℃, 2 hours, nitrogen gas special magnetic field: Wl5AO=7W
Af, B10 = 16KGa As is clear from the above examples, according to the method of manufacturing a thin metal sheet of the present invention, a thin metal sheet having special characteristics such as an electric iron plate can be directly obtained with a simple process and a lot of man-hours. , does not require equipment such as large-scale rolling equipment,
Since the number of rolling steps can be omitted, it can be manufactured at low cost.

Furthermore, when making electric iron plates, there are fewer intermediate steps such as rolling, so there is less non-uniformity during the process.

Furthermore, the plate thickness can be easily adjusted by adjusting the rotational speed of the rollers and the amount of molten metal being blown out and dropped, and the double-roll method makes it possible to obtain a particularly flat and accurate plate thickness. Furthermore, magnetic properties can be improved by repeating recrystallization annealing and skin bath steps. Furthermore, a composition that is difficult to achieve by rolling (4%
A thin film of Si (Si iron, etc.) can be easily obtained and can be put to practical use as an electric iron plate, etc., and since heat treatment is performed, aging phenomena due to distortion etc. do not occur.

It should be noted that although the above embodiments have been described with a focus on electric iron plates, it is of course applicable to other uses as well.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a method of manufacturing a thin metal plate showing one embodiment of the present invention, and FIG. 2 is an explanatory diagram of a method of manufacturing a thin metal plate showing another embodiment of the invention. 1... Molten metal, 2, 4... Roller,
3,5... Metal thin plate.

Claims (1)

[Claims] 1. Molten metal containing iron as a main component is continuously blown onto rollers rotating at high speed to form a thin plate, and then heat treated at least twice, and a skin pass is applied between the heat treatments. A method for manufacturing a thin metal sheet, characterized by: 2. Claim 1, characterized in that the heat treatment is performed by any one of recrystallization annealing, decarburization annealing, and alpha ironization annealing.
A method for producing a thin metal plate as described in Section 1.