JPS5843444B2 - Manufacturing method of electromagnetic silicon steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to cube-on-edge orientation (Cnbeon
-edge -orientation) and a magnetic permeability of at least 1850 (G10e) at 10 oersteds.

Oriented silicon steels containing 2.60 to 4.0% silicon are generally processed by processes including hot rolling, double cold rolling, annealing prior to each cold rolling, and high temperature microstructural annealing. Manufactured by.

In recent years, several patents have been published in 10 Oersted, 18
A method for manufacturing silicon steel having a magnetic permeability of 50 (G10e) or higher is disclosed.

Among them, U.S. Pat.
Nos. 456 and 3636579 seem to be the most interesting.

However, the method described in one US patent application is even more interesting.

This is 1973 US Patent Application No. 357,974.

The process described in this U.S. application consists essentially of carbon at 0.07% 1, silicon at 2.6 to 4.0, and manganese at 0.03 to 0.24. and 0.01
Consisting of sulfur at 0.07%, aluminum at 0.015% to 0.04%, nitrogen at 0.02% 1, copper at 0.1 to 0.5%, and the balance iron. preparing a melt of steel; hot rolling said steel; annealing said steel at a temperature of 760°C to 1175°C prior to final cold rolling; From a temperature of 343°C, at least 260°C, using a liquid quenching medium or gas flow, and from its highest annealing temperature, from 926°C to 343°C, the steel is A continuous process consisting of cooling in a target atmosphere, or in which the only intentional movement is the movement imparted to the steel, but there is some relative movement between the atmosphere and the steel. The steps include cooling the steel at a rate no less than the rate at which it is cooled in the line, and cold rolling the steel at a reduction of at least 80 degrees.

In accordance with the present invention, another improved method is described for producing silicon steel having a cube-on-edge orientation and a magnetic permeability of at least 1850 (G10e) at 10 oersteds.

This is mainly because in the above-mentioned US application and No. 524,831 filed at the same time, the fermentation product is
It is based on the discovery that it can be adjusted by changing the boron content.

That is, boron has been effectively used as a promoter to produce high magnetic permeability in grain-oriented silicon steel.

This is primarily based on the discovery in the aforementioned U.S. Patent Application No. 357,974 that the melt can be prepared by replacing part or all of the sulfur contained therein with selenium. .

Therefore, it is an object of the present invention to improve the cube-on-edge orientation (
Cnb e -on -edge -orientat
ion) and at least 1 in 10 oersted
The object of the present invention is to provide a method for producing an electromagnetic silicon steel with a magnetic permeability of 850 (G10e).

The present invention provides a method for producing silicon steel having a cube-on-et orientation and a magnetic permeability of at least 1850 (G10e) at 10 oersteds.

This process essentially includes, by weight, carbon at 0.07, silicon at 2.67 to 4.0, and silicon at 0.03 to 0.
．． 24% manganese and 0.01 to 0.09φ,
A material selected from the group consisting of sulfur and selenium;
0.015-0.04% aluminum and 0.02%
Nitrogen at %1, copper ranging from 0.1 to 0.5, and 0.00
preparing a silicon steel molten body comprising 0.045 to 0.0035% boron and the balance iron; casting said steel; hot rolling said steel into hot rolled strip steel; , subjecting the steel to at least one cold rolling; subjecting the steel to a final annealing prior to final cold rolling; subjecting the steel to a decarburization treatment; and subjecting the steel to a final annealing process. The steps of applying tissue annealing are included.

It is important to note that the following specific processing stages are also included.

That is, prior to final cold rolling, a final annealing is performed at a temperature of 760°C to 1175°C for a period of 15 seconds to 2 hours, from a temperature of 926°C to 343°C, at least 26°C.
A liquid quenching medium or gas flow is used at a low temperature 1 of 0°C, and from a maximum annealing temperature of 926°C to 3°C.
At a temperature 1 of 43°C, the rate at which the steel is cooled in a static atmosphere or the only intended motion is the motion imparted to the steel, but there is no difference between the atmosphere and the steel. cooling the steel at a rate no faster than the rate at which it would be cooled in a continuous process line where there is associated motion, and cold rolling the cooled steel at a reduction of at least 80%. Consists of doing.

This will be even more advantageous.

Conditions include annealing at a temperature of 981°C to 1152°C, cooling from a temperature of 860°C to 537°C with a liquid quenching medium or gas flow, and at least 85°C of pressure. Includes cold rolling.

The above-mentioned melting, casting, hot rolling, cold rolling, decarburization and final structure annealing do not involve any new processing steps as far as technology is concerned.

With respect to these processing steps, the invention therefore encompasses all applicable steelmaking measures.

However, with regard to cold rolling, several rolling steps may constitute only one cold rolling operation, and only if several cold rolling steps are separated by annealing. This is intended to point out that there are multiple cold rolling operations.

In addition to ferrous metal, melting steel must contain silicon, aluminum, manganese, sulfur, and/or selenium.

Silicon is necessary because it increases the resistance of the steel, reduces its magnetostriction, reduces its magnetocrystalline anisotropy, and thus reduces its core losses.

Aluminum, manganese and sulfur and/or selenium are necessary because they form important inhibitors for controlling the orientation of the steel and its dependent properties.

More specifically, aluminum combines with nitrogen, either in the steel or from the atmosphere, to form aluminum nitride;
Manganese combines with sulfur and/or selenium and optionally copper to form manganese sulfide and/or manganese copper sulfide, and/or manganese selenide and/or manganese copper selenide. do.

Together, these compounds are used during final tissue annealing.
It has the required cubic crystal orientation while inhibiting normal grain growth.

Assists the generation of secondary recrystallized particles.

Although copper is mentioned above as being present in the manganese inhibitor, copper may also have a beneficial effect during the course of the infiltration process.

That is, copper hypothetically lowers the annealing temperature, lowers the temperature at which rapid cooling can occur, improves rollability, simplifies melting procedures, and relaxes annealing ambient requirements.

Additionally, copper increases the resistance of the steel and reduces its core losses.

In particular, steel suitable for applying the method of the invention mainly contains 0.02 to 0.07% carbon and 2.6% by weight.
5 to 3.25% silicon, 0.05 to 0.20% manganese, 0.02 to 0.07% of a material selected from the group consisting of sulfur and selenium, and 0.015 to 0. .04% aluminum, ◆-0,0030 to 0.0090% nitrogen, and o,i to 0.4% copper;
It consists of 0.0005 to 0.0025% boron and the balance iron.

This steel balances its chemical composition to create a highly advantageous structure when processed according to the present invention.

As a general standard, the content of boron is It is supposed to be 0.0007% or more.

Although it is not certain why the final annealing and controlled cooling of the present invention prior to the final cold rolling described above is effective, hypothetically, the annealing provides the steel with conditions for cold rolling and inhibits it. providing an operation for forming an agent; and
Gradual cooling at temperature 1 of 926°C and/or using an annealing temperature in the lower part of the annealing temperature range indicates that the austenite and ferrite phases are present and therefore at slightly higher temperatures each phase In contrast to the different susceptibilities to inhibitors in steels at temperatures below 926°C, the uniformity of the distribution of inhibitors due to the presence of mainly ferrite phase flakes in steels at temperatures below 926°C. It is inferred that this is due to the increase in

As discussed above, the primary inhibitors are aluminum nitride and manganese sulfide and manganese selenide.

There are no particular restrictions on the annealing temperature.

Thus, the ambient air includes, for example, nitrogen, reducing gases such as hydrogen, inert gases such as argon, air, and mixtures thereof.

The following examples illustrate several aspects of the invention.

Four batches of condensate steel were cast and prepared into silicon steel with a cube-on-edge orientation.

The chemical composition of each batch is shown in the table below.

The treatments for any of the above batches included soaking at high temperature for several hours, hot rolling to a gauge thickness of about 2.36 nm, heat treatment at 1120°C for 1 minute, and gradual rolling at 948°C. (for about 50 seconds), air cooling at 593°C1, water quenching at 593°C1, cold rolling to a final gauge thickness of about 0.3 am, wet rolling. The steps include decarburization in a mixture of hydrogen and nitrogen at a temperature of 801°C, and a final structural annealing at a maximum temperature of 1175°C.

Each batch was tested for magnetic permeability and permeabilities of 1906, 1889°, 1873 and 1898 (G10e) were recorded at 10 oersteds, respectively.

Claims (1)

[Scope of Claims] 1. Preparing a melt of silicon steel, casting the steel, hot rolling the steel into a hot rolled strip, cold rolling the steel for at least one period. a cube-on-etch orientation ( Cube
-on -edge orientation) and
At least 1850 in 10 Oersted (G10
e) In the method for producing an electromagnetic silicon steel having a magnetic permeability of
final annealing at a temperature of 760° C. to 1175° C. for a period of time, from a temperature of 926° C. to 343° C. of said steel, at a temperature as low as 1 of at least 260° C. without the flow of liquid quenching medium or gas; used, and from its maximum annealing temperature,
In the 926°C to 343°C temperature trench, the rate at which the steel is cooled in the static atmosphere or the only intended movement is the motion imparted to the steel, but the cooling said steel at a rate no faster than the rate at which it is cooled in a continuous processing line in which there is a relative motion between said steel and said cooled steel being reduced by at least 80%; including the steps of cold rolling in the step;
and said molten steel essentially contains, by weight, 0.07% carbon, 2.60 to 4.0% silicon, and 0.03 to 0.0% silicon.
a material selected from the group consisting of sulfur and selenium, 0.01 to 0.09φ;
015 to 0.04φ aluminum and 0.02 ratio 1
nitrogen at 0.1 to 0.5% copper and 0.0004
A method for producing electromagnetic silicon steel, characterized in that it is made of boron of 5 to 0.0035% and the balance iron.