JPS6026812B2 - Manufacturing method of unidirectional electrical steel sheet with extremely high magnetic flux density - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an easy magnetization axis of <100 in the rolling direction of a steel plate.
> direction, and has a {110} plane parallel to the rolling surface, especially a grain-oriented electrical steel sheet, especially magnetic flux density B,.

The present invention relates to a method for manufacturing unidirectional electrical steel sheets with extremely high values. Unidirectional electrical steel sheets are mainly used as iron for transformers and other electrical equipment, and have excellent magnetization properties, that is, high magnetic flux density as magnetization properties.
Low iron loss is required.

In particular, recent technological improvements have made it possible to obtain magnetic flux densities with extremely high magnetic flux densities (represented by the Bo value). In order to obtain a unidirectional silicon steel sheet with good magnetic properties, {11
It is necessary that the secondary recrystallized grains are highly aligned in the order of 0} and 100>.

In order to complete this secondary recrystallization, a suitable precipitated dispersed phase called an inhibitor, such as NN, MnS, MnSe, etc., is present in the steel plate before finishing, and {110}<1
It is already well known that primary grain growth other than 00> needs to be effectively suppressed. {110}ku10
Since secondary recrystallized grains with a 0> orientation are often generated in a layer close to the surface of the steel sheet, we place particular emphasis on the surface of the steel sheet and improve the properties of the surface layer through chemical treatment at each stage during the manufacturing process. A method for improving magnetic properties by this method is already known.

A typical method is to add some compounds to the separation agent before the final finishing of the sintered anchor.
This is a method of effectively suppressing primary grain growth by adding a sulfur compound to the Akatsuki stripping agent before the final finish firing described in No. 96, and sulfurizing the sulfur content on the surface during the Akatsuki. . However, when using this method, it is difficult to uniformly apply the sulfur compound over the entire area of the steel sheet and to exhibit its effect over the entire area. The purpose of the present invention is to provide a new method that improves the drawbacks of the conventionally known methods. After applying a dilute aqueous solution or suspension containing a tellurium compound to the surface of a steel sheet, annealing is performed in the middle of the process. By increasing the suppressive force near the surface,
The present invention relates to a method for producing grain-oriented electrical steel sheets that are uniform over the entire steel sheet area and are certainly superior to other inhibitors.

Next, the present invention will be explained in detail.

According to the present invention, a conventional unidirectional silicon steel material, i.e. 2-4% Si, CO. 06% or less, Mno. 01~0.
A silicon steel ingot containing 20% of an inhibitor selected from S, Se, AI, Sb, Bi, As, and Sn can be used.

The port making method and the casting method may be any method, and the steps from hot rolling to finishing of the finished sintered anchor can be those normally adopted, but in the present invention, the steps before cold rolling 0.001 to 0.1 mol of an inorganic compound containing tellurium in at least one of the steps before homogenized sintering, after cold rolling and before decarburization phosphorus annealing, or after decarburization of the anchor.
It is important to uniformly apply a dilute aqueous solution or suspension containing the concentration range to the surface of the steel plate within a range of 2 to 50 coats per unit area. The present invention will be explained using experimental data.

C.O. 034%, Si2.96%, Mno. 049%,
Sbo. 032%, Seo. After hot-rolling a silicon steel slab containing 0.022% to make a hot-rolled sheet with a side thickness of 1.7%, after pickling it
K2Te at a concentration of 0.5-0.0001 mol/℃
03, Na2Te03, QTe04, immersion groove in Pan 20 aqueous solution, after coating, homogenized sintering, 80% cold rolling, decarburization,
The magnetic properties of the final finished sintered anchor are shown in T after pickling.
Figure 1 shows the results of comparison between those not treated with e-compound and those treated with selenide and sulfide.

The amount of each treatment liquid applied is determined by a solution concentration of 0.00.
01 mol/in that case, 0.001 to 0.05 mol/,
Also, 0.001 mol/in that case, 0.5 to 5 mol/re,
0.01mol/*In that case, 3-8 evenings/〆, and 0
．． It was about 5 mol/in that case, 60 to 100 mol/end.

From the same figure, it can be seen that the magnetic flux density of the Te compound-treated specimen is higher than that of the other treated specimen.

C.O. 04%, Si3.19%, Mno. 076%,S
O. 02%, NO. 016%, NO. After hot-rolling a silicon steel slab containing 0.066% to make a hot-rolled plate with a thickness of 1.7,
Coating experiments were conducted using the following five steps. ■ Homogenized steel before cold rolling Pre-painting pickling - Te compound coating - Homogenizing sintered anchor - Cold rolling - Decarburization annealing -
Mg○ coating - Final fired chicks - Pickling applied before rolling - Homogenized sintered anchor - Te compound application - Cold rolling - Decarburized sintered anchor -
Mg○ coating - Final sintered anchor■ Coating before decarburization and annealing Pickling - Homogenized sintered anchor - Cold rolling - Te compound application - Decarburization annealing -
Mg○ coating - Final annealing■ Coating after de-blurring and hammering Pickling - Homogenization annealing - Cold rolling - Decarburization annealing - Te compound coating -
Mg○ Coating - Final Anchor ■ Uniformization before cold rolling Coating before rolling and applying after decarburizing hot hammer Pickling - Te compound coating - Uniform firing - Rolling - Decarburization annealing - Te compound coating - Mg ○Application-
K2Te08,Na is applied in 5 types of coating processes beyond the final scorching anchor.
2 ratio Te06, K2Te04, 9th 20 and day 2Te0
0.01 mol at 8000 using 4.2LO as a reagent
Table 1 shows the magnetic properties of the untreated material when the concentration was applied and the coating amount was about 7 days/coating.

It can be seen that magnetic properties superior to the untreated material can be obtained in all cases except for the conditions for coating before lining shown in Table 1 (2).

The method of applying the Te compound in the present invention is to use an aqueous solution as a rinsing solution or an electrolytic solution, or to apply it uniformly onto the surface by dipping, dropping, spraying, or transferring after degreasing and washing with water. It should be dried after application.

When applying such an aqueous solution or suspension of Te compound, the concentration should be adjusted to 0.001 to 0.1 mo1/2 to 50% per unit area of the steel plate.
It is necessary to apply it evenly in the evening area.

This is because when the concentration of the treatment liquid is less than 0.001 mol/day, no improvement in magnetic properties is observed. On the other hand, 0.1
When it becomes denser than mol/that, the magnetic properties deteriorate,
Furthermore, even if the concentration is within the appropriate range, if the coating amount is less than 2 days/force, the additive effect will be poor, while if it exceeds 50 days/force, it will have a negative effect on the insulating film formed during the finishing process. This is because, in particular, if the coating treatment is performed before decarburizing the sintered anchor, decarburization becomes difficult. When treated with the above treatment solution concentration and application amount, the amount of Te that adheres to the surface of the steel sheet is approximately 0.0002 to 0.7 m/m, and by adhering this amount of Te to the surface of the steel sheet, a good This results in a significant improvement in magnetic properties.

Furthermore, it goes without saying that a mixed solution or suspension of two or more types of Te compounds may be applied.

Note that the effects of the present invention can be better obtained by a so-called one-step method in which a hot-rolled sheet is cold-rolled once to achieve its final thickness.

C.O. 034%, Si2.96%, Mno. 049~%
, Sbo. 032%, Seo. After hot-rolling the silicon steel soul containing 0.022% to form a hot-rolled plate with a thickness of 3 sides from the 1.5 side,
0.01 mo at 80 qo before homogenization after pickling and before cold rolling
l/Immersion treatment in the K2Te03 aqueous solution (approximately 8 coated amount)
~10 evenings/final), then homogenized annealing from 56% to 86%
The magnetic properties when cold rolled, decarburized, and the final finish scales are
As shown in the figure.

It can be seen from the figure that excellent magnetic properties are obtained when the rolling reduction is 70% or more. Next, the present invention will be explained with reference to examples.

Example CO. 032~0.044%, Si2.98~3.20
%, Mno. 052-0.064%, SO. 00
4-0.021%, Sao. 023-0.028%, S
bo. 024-0.026%, Bio. 013~0.0
14%, ASO. 01-0.030%, Sno. 015
Seven types of silicon steel ingots containing one or more types selected from ~0.020% were hot-rolled into hot-rolled plates with a wall thickness of 1.7.

Thereafter, the following three types of manufacturing steps were performed. ■ Homogenization before cold rolling Applying before dulling with phosphorus Pickling - K2Te03 aqueous solution application - Homogenization Akatsuki Anchor - 82% -
Cold rolling - Decarburizing hot hammer - Mg○ application - Final hammering ■ Pre-decarburizing baking anchor coating Pickling - Homogenizing baking anchor - 82% cold rolling - K2Te03 aqueous solution application - Decarburizing baking hammer - Mg○ coating - Final knee hammer ■ Acid Washing - Homogenization Akatsuki - 82% cold rolling - Decarburization phosphorus dulling - K2Te03 aqueous solution application - Mg0 application - Final sintered anchor K2 used in the above application process
The Te03 aqueous solution was applied uniformly over the entire surface of the steel plate at a concentration of 0.01 mol/approximately 5 days/day.

Further, the homogenizing hammer before cold rolling was rolled at 950 oo for 1 minute, and the cold rolling was rolled by 82% to a thickness of 0.3 mm. Decarburization is 820qo
After being heated in warm hydrogen, the final finished shochu is 15 qo/hr.
After slow heating and sufficiently growing secondary recrystallized grains, 11
It was held at 80oo for 5 hours. The magnetic properties Bo obtained as a result were uniformized before cold rolling, and the untreated material (normally processed material without coating) was classified according to the coating conditions of coating before racing anchor, coating before decarburization, and coating after decarburization.
A comparison is shown in Table 2. Table 2 and above According to the present invention, it is possible to uniformly and reliably produce an excellent unidirectional electrical steel sheet over the entire area of the steel sheet.

[Brief explanation of the drawing]

A diagram showing the relationship between the concentration of the dilute aqueous solution and the magnetic flux density in Figure 1,
FIG. 2 is a diagram showing the relationship between final cold rolling reduction (%) and magnetic flux density. Figure 1 Figure 2

Claims (1)

[Claims] 1 In a series of manufacturing methods for unidirectional silicon steel sheets in which a silicon steel slab containing an inhibitor is hot-rolled into a hot-rolled sheet, which is then subjected to cold rolling, decarburization, and final annealing, , after cold rolling and before decarburization annealing or after decarburization annealing, in at least one step selected from the following, a diluted product containing an inorganic compound containing tellurium in a concentration range of 0.001 to 0.1 mol/l. A method for producing a unidirectional electrical steel sheet with excellent magnetic properties, which comprises uniformly applying an aqueous solution or suspension to a steel surface in an amount of 2 to 50 g per 1 m^2 of the steel surface.