JPS60152633A - Manufacture of thin strip of high-silicon iron alloy having superior magnetic characteristic - Google Patents

Abstract

PURPOSE:To manufacture stably thin plates of a high-silicon iron alloy having superior soft magnetic characteristics such as 30-60mOe coercive force and high suitability to blanking in large quantities by forming a molten high-silicon iron alloy contg. a specified amount of Si into each thin plate by a very rapid cooling method and by subjecting the thin plate to two-stage annealing under specified conditions. CONSTITUTION:A molten high-silicon iron alloy contg. 2-8wt% Si is formed into each thin plate by a very rapid cooling method. The thin plate is subjected to the 1st-stage annealing at 1,000-1,300 deg.C for 5min-12hr in vacuum of 1X10<-8>-1X10<-1>Torr or in a gaseous atmosphere of one or more among Ar, N2 and He contg. 1-500ppm one or more among O2, H2O and an S compound. The thin plate is then subjected to the 2nd-stage annealing at 1,050-1,300 deg.C for <=1hr in vacuum of 1X10<-8>-5X10<-4>Torr.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high silica alloy thin plate having excellent soft magnetic properties, and a method for producing it efficiently and stably.

<Industrial Application Fields> In general, high-silicon iron alloy sheets with an 84 content of around 2 to 596 (hereinafter referred to as weight percent) are used in generators, transformers, electric motors, etc. It is used as a magnetic core and is considered an extremely important soft magnetic material in the electrical industry.

Conventionally, the above-mentioned high-silicon iron alloy plate has been produced by hot rolling and multiple cold rolling with intermediate annealing to obtain a thin plate with a uniform composition.

It was then common to produce annealed syllables under strict conditions to improve their magnetic properties. Therefore, a large number of steps are required to obtain the product, and the manufacturing cost is inevitably high.

Because of this L, in recent years, so-called "
Attempts have been made to apply the ultra-quenching method to directly produce thin sheets from high-silicon iron alloy baths without undergoing plastic processing such as rolling. For example, in addition to the single-roll method and twin-roll method shown in the schematic diagrams in Figures 1 and 2, methods that use the entire cooling cylinder are known for the "quench cooling method," but in short, continuous cooling methods are known. The method of directly forming a thin ribbon by injecting molten metal onto the surface of a cooling body that is being moved and renewed is collectively called the "ultra-quenching method." In Figs. 1 and 2, the reference numeral 1 indicates a molten metal container, the reference numeral 2 indicates a molten metal spouting nozzle, and the reference numeral 3 indicates a cooling roll.

The product designated by numeral 4 is a strip-shaped thin plate product.

The high-silicon iron alloy ribbon produced by the ultra-quenching method is
It is now attracting attention as a material for the main wings of future low-core loss electromagnetic steel sheets.

However, the high-silicon iron alloy ribbon produced by the ultra-quenching method and still at 7C had poor magnetic properties due to large distortions and very small crystal grains, so the conditions were subsequently strictly regulated. The texture is changed to (100) by special annealing at high temperature.
The process of growing crystal grains while adjusting <okt> or (100)<011> to completely improve the soft magnetic properties is essential.

As representative methods of this type of annealing, the following methods (1) and (2) have been proposed. That is.

■ In a vacuum of 1 x 10-2 to 5 x 10''7 Torr.

Temperature: Method of annealing at 1050 to 1300°C (Japanese Patent Application Laid-open No. 87627/1983).

eD02. Impurity gas f 1 such as H2S, H, O, etc.
All characteristics include annealing at a temperature of 600°C or higher in a non-oxidizing atmosphere containing ~500 ppm (i
oo) (011) High-silicon iron ribbon containing texture (JP-A-58-45349).

However, the high-silicon iron alloy thin plate material manufactured by the ultra-quenching method used in the above-mentioned annealing process has a retention crab of 50~
Good soft magnetic properties of 2QQmoe can be exhibited, but the methods shown in (1) and (2) above both require a narrow range of annealing conditions for obtaining good soft magnetic properties and require a controlled atmosphere containing impurities. When used above, the atmosphere control is difficult, and the coercive force of the resulting product tends to vary, which is not preferable for the stable production of products of desired quality.

In recent years, there has been a tendency for demands on the properties of soft magnetic materials to become more and more sophisticated, and it is becoming increasingly difficult to satisfy these demands with a retention force of about 50 to 200 moa.

Problems with this have been increasingly pointed out.

<Purpose of the Invention> From the above-mentioned viewpoint, the present inventors have made use of the advantages of the ultra-rapid solidification method, and have achieved excellent magnetic properties and In particular, as a result of research to find a means to stably manufacture high-silicon iron alloy thin sheets exhibiting a coercivity of 30 to 5 QmOei, we found the following (
We have come to the findings shown in a) to (d).

Findings〉 (a) When ultra-quenched high-silicon iron alloy thin plate material is treated by the methods shown in ■ and ■ above,
It is only possible to obtain soft magnetic properties of the order of e.

■ Among the methods of ■ above, annealing '1ixio-8: T
When the process is carried out in a vacuum of orr or higher, or when the method (①) is used, the 0, , H2 remaining in the vacuum
A scale of the order of 100 OA is formed on the surface of the thin plate due to O or S compounds or those mixed in a non-oxidizing atmosphere, and as a result, the surface energy fully promotes the growth of crystal grains with (100) planes parallel to the plate surface. However, on the other hand, the movement of the domain wall is inhibited by the impurities that have entered the surface of the thin plate material, and as a result, the soft magnetic properties are not sufficiently improved.

■ Among the methods of ■ above, annealing klX10-8 Torr
When carried out in a vacuum of less than 10 Torr, the growth of crystal grains with (100) planes parallel to the plate surface tends not to be sufficiently promoted. 110) plane appears on the plate surface, and the (110) plane appears on the plate surface.
)<htit> texture, which adversely affects magnetic properties.

That is the biggest reason.

(b) However, when a high-silicon iron alloy thin sheet material obtained by an ultra-quenching method is heated in a low vacuum of 10-'Torr or more or with a slight amount of one or more of O, 1-4O, and S compounds, By annealing in a non-oxidizing atmosphere containing The second annealing syllable in a high vacuum of less than
is easily removed, the domain walls move smoothly, and the soft magnetic properties are further improved.

(c) In this case, it becomes possible to set the annealing conditions for the first stage to be sufficiently looser than those in the methods shown in (1) and (3) above, and the annealing conditions for the second stage can also be set to Since it is not very severe, processing work is relatively simple, and products with consistent quality can be stably manufactured even during disaster work.

(d) L Wb 4. The high-silicon iron alloy thin plate material subjected to such two-stage annealing treatment has no scale on one surface, and therefore has extremely good punchability.

7- <Structure of the invention> This invention was made based on the above knowledge.

8i:2. First, a high-silicon iron alloy molten tube containing O ~ 8.0%' is made into a thin plate by an ultra-quenching method.

■ I X 10= ~ I X 10-'' Torr vacuum, or a gas atmosphere consisting of one or more of Ar, Nl, and One or more types of i1-500
In an atmosphere containing ppm.

Processing temperature: 1000-1300℃, Processing time: 5 minutes to 12 hours The first stage of annealing is performed.

■ 1, X 10= ~5 X 10-' Torr
Q) By performing the second stage annealing in a vacuum, processing temperature: 1050-1300℃, processing time: within 1 hour, the high-silicon iron alloy thin plate with extremely excellent magnetic properties is completely stabilized and reliably produced. , 〃λ It can be manufactured at a relatively low cost.

It has the following characteristics.

8- In addition, the "high silicon iron alloy" mentioned above means: Si: 2.0
~8.0% F with the remainder being substantially Fe
e-8i alloy +7)? ”LP%2.0~8.0T
o In addition to 8i, 0.5- or less Ni, 1% or less V)
Co, less than 0.5% red.

Mn below 0.5%, Mo below 1%, 0.5%
Below is Zr.

Naturally, it refers to any of the high-silicon iron alloys conventionally known as lQs and other materials with good soft magnetic properties, which contain one or more types of B such as 0.5 gb or less. .

tyc, rsubstantially made into a thin plate using an ultra-quenching method.

It is possible to obtain a thin plate of desired thickness (for example, 20 to 200 μm) directly from a high-silicon iron alloy bath using only the ultra-quenching method, as well as to obtain a thin plate of a desired thickness (for example, 20 to 200 μm) from a high-silicon iron alloy molten metal using an ultra-queue cooling method. , further 11 or multiple (b) rolling with intermediate annealing (
This includes applying hot rolling and cold rolling to adjust the shape, surface properties, etc., as well as making a thin plate with a desired thickness.

The two-stage annealing is usually performed in a patch furnace, but in that case, the temperature may be lowered to around room temperature after the first-stage annealing, and then the second-stage annealing may be performed. After the first stage annealing, the second stage annealing continues without the temperature decreasing.
It is economically advantageous to perform stage annealing. Additionally, both stages of annealing may be carried out in the same furnace; in this case, after the first stage annealing, the atmosphere or vacuum level in the furnace can be adjusted to 1:t without raising or lowering the temperature of the treated material. It is preferable to complete the second stage annealing by also adjusting the temperature.

Furthermore, as mentioned above, sufficient effects can be obtained by performing the first stage annealing in a completely low vacuum, but if equipment costs are taken into consideration, one or more of Ar, N2, and Ru (of course, in a gas atmosphere consisting of 0.

1~50Oppm of 0 and 1 of S compounds or more
Advantageously, it is carried out with (containing)

In short, this invention is produced by ultra-quenching method.
9i6 siliceous alloy ribbon t, first, lXl0 ~ 1x10
-' Torr vacuum or 02. H,0,S
Annealed in a non-oxidizing atmosphere containing compounds and then.

By annealing again in a K vacuum at a temperature of I x 10 = ~5 x 10-' Torr, high-silicon iron has excellent magnetic properties and good punchability, with a coercive force that is much lower than conventional materials. This article is about how to obtain thin alloy sheets.

The range of annealing conditions in the first stage is also relatively gentle.

Although it is possible to stably obtain high quality products,
In the method of this invention, the 8i content in the iron alloy, the degree of vacuum during annealing, the 02. N20
8 The reason why the compound content, annealing temperature, and annealing time are numerically limited as described above will be explained.

k) If the 81 content in the 8i-containing high-silicon iron alloy is less than 2.0%, the desired good soft magnetic properties cannot be obtained;
If Si content exceeds ', embrittlement becomes severe, and
Since the saturation magnetic flux density decreases, the Si content is 1! -2
, 0 to 8.0%. In addition, when considering subsequent processability, etc., it is preferable to set Si content@f to approximately 2.0 to 7.0.

B) First-stage annealing conditions ■ Atmosphere: When annealing is performed in a non-oxidizing gas (Ar, N2, and He) atmosphere, O, N20, and one of the S-based metals in the atmosphere are used. If the above content is less than 1 ppm, the desired scale will not be formed on the surface of the plate, and the growth of crystal grains with (100) planes parallel to the plate will slow down, while the content will be less than 500 pI) m' 03, HxO and 1ai of the 8 compounds.
The above content t'tl was determined to be 500 ppm.

tyc, when the first stage is annealed in a vacuum, if the degree of vacuum is lower than I The amount of wrinkles is less than the required wrinkle, and the desired scale of the IC fabricated above cannot be formed.
If the degree of vacuum is lower than rr t, the scale will become too strong and will not be removed during the second stage annealing, and as a result, good magnetic properties cannot be achieved. ˜I×10−”Torr.

■ Annealing temperature 12 - If the annealing temperature is less than 1000°C, the desired grain growth will not occur, while annealing at a temperature exceeding 1300°C will cause many technical problems in the work. The temperature was set at 1000 to 1300°C.

[Phase] Annealing time If the annealing time is less than 5 minutes, the desired grain growth will not be achieved sufficiently. On the other hand, annealing for more than 12 hours will result in high manufacturing costs, so the annealing time should be 5 minutes or less. It was set as 12 hours.

C) Second-stage annealing conditions ■ Vacuum degree In the first-stage annealing, as mentioned above, processing is performed in an environment containing rounding impurities (OstH20 and S compounds) for texture adjustment. Impurities are mixed into the surface and inside of the plate material, and if left untreated, the magnetic properties will be impaired. Therefore, the second stage annealing is carried out to remove this mixed impurity.
At low vacuum levels exceeding Torr f, oz, Tsuru o and S
Impurities brought by compounds etc. are not sufficiently removed, and the movement of domain walls is inhibited, resulting in deterioration of soft magnetic properties, and the effect of improving punchability is not sufficient. Even if annealing is performed at a high vacuum degree below 8 Torr t, no more noticeable effect on magnetic properties or punchability is observed, so lX10-8~5X
It was decided that the second stage annealing session would be performed in a vacuum of 10-' Torr.

■ Annealing temperature If the annealing temperature is less than 1050°C, the above 02. ) Impurities caused by i, O, S compounds, etc. are not sufficiently removed, and annealing at temperatures exceeding 1300°C poses many technical problems in actual work. The temperature was set at 1050-1300℃ 7. [Phase] Annealing time When the annealing time exceeds 1 hour, the temperature is set to 1050-1300℃.
The annealing time was determined to be within 1 hour because crystal grains with planes would grow and deteriorate the soft magnetic properties. Note that the lower limit of the annealing time is not particularly limited, and in short, it may be a time that allows sufficient removal of impurities, but preferably the annealing time is 1 minute or more.

Next, the present invention will be explained using Examples and comparing with Comparative Examples.

Examples> Example 1 First, Fe = Si alloy molten metal containing 5.7% and 6.7% of Si alloy, and the balance being substantially Fe.
Each of these was ejected from a nozzle hole of 0.5 .phi., and was directly formed into a thin ribbon with a thickness of 60 mm using the twin roll method as shown in FIG.

Next, this thin plate was annealed under the conditions shown in Table 1, and the coercive force of the obtained thin plate product was measured.

These results are also shown in Table 1.

The results ηλ and others shown in Table 1 show that the method of the present invention is superior to the method of annealing only 1 (b), which has not been previously reported, or the comparative method in which the processing conditions are outside the scope of the present invention. It is clear that the method of the present invention is a method for producing materials with excellent soft magnetic properties.

Example 2 Contains 5.7 8i and the remainder is substantially F
The molten Fe-8i alloy (e) was made into a 60 μm thick ribbon using the same twin roll method as in Example 1.

Next, a plurality of samples tvJ were taken out from this thin plate.

First, the specimens were annealed at various temperatures and times in a vacuum of I x 10-2 Torr to grow grains of crystals with (100) planes parallel to the plate surface.

After the thin plate material obtained in this manner was cooled to room temperature, the relationship between annealing conditions and coercive force was fully investigated.

It is shown in Figure 3 as a coercive force contour map. .

Then, for each of these thin plates, further.

Vacuum degree: 10-6 Torr.

Processing temperature: 1200℃.

Processing time: 150 seconds of second stage annealing, and the coercive force contour map is plotted and shown in Figure 4 IC trap.

Comparing Figures 3 and 4, the degree of vacuum is low.

Therefore, in one-time annealing in an atmosphere containing impurities, the range of annealing conditions where the coercive force is 75 m0e or less is narrow (3rd
Although it is clear that control in actual production is difficult, when a second stage of annealing is performed, the coercive force is further reduced and a good soft magnetic field is obtained. It is clear that the range of annealing conditions in the first stage, which is essential for obtaining a characteristic material, can be greatly expanded (Figure 4).

Example 3 First, molten high silicon iron alloy having the composition as shown in Table 2 was coated with a thickness of 60 μm using the same twin roll method as in Example 1.
It became thick and thin.

Next, these were treated in 1100 pp of 02-containing gas at a treatment temperature of 1100°C.

Processing time: 60 minutes of first stage annealing, followed by charging into a vacuum annealing furnace without substantial temperature drop.

Vacuum degree: 1O-6Torr.

Processing temperature: 1200°C.

Processing time: 150 seconds The second stage of the syllable was annealed.

The results of measuring the coercive force of the thin plate product thus obtained are also shown in Table 2.

It is clear from the results shown in Table 2 that a high-silicon iron alloy thin plate material with excellent soft magnetic properties can be obtained by the method of the present invention.

<Overall effect> As mentioned above, if this invention is applied, the coercive force can be increased from 30 to 59
A high-silicon iron alloy thin plate material with excellent soft magnetic properties of m0e and good punching properties can be efficiently and stably mass-produced by %λ1.1 Generator.

This brings about extremely useful effects industrially, such as greatly contributing to improving the performance of transformers, electric motors, etc.

[Brief explanation of drawings]

Figure 1 is a schematic diagram showing how thin sheets are manufactured using the single roll method, which is one of the molten metal ultra-quenching methods, and Figure 2 is a schematic diagram showing how thin sheets are manufactured entirely using the twin roll method. Figure 3 is a schematic diagram illustrating the situation; Figure 3 is a coercive force contour diagram of a high-silicon iron alloy thin plate obtained using the conventional method of annealing only once;
The figure is a coercive force contour map of a high-silicon iron alloy thin plate obtained by the uninvented method. Please refer to the diagram. 1... Molten metal container, 2... Molten metal spouting nozzle, 3...
Cooling roll, 4... band-shaped thin plate product. Applicant Sumitomo Metal Industries Co., Ltd. Agent Tomi 1) Kazuo is 70 years old, 1 person C-) 11
W! H'Ir

Claims (3)

[Claims] (1) 8i: A high-silicon iron alloy molten metal containing approximately 2.0 to 8.0 weight is made into a thin plate by substantially ultra-quenching method. first. ■ In a vacuum of I X 10-8 to I X 10-' Torr, or in a gas atmosphere consisting of one or more of Ar, N2, and He0, with a temperature of 73 to 0. , H2O and S compounds in an atmosphere containing 1 to 5001) pm. Processing temperature: 1ooo~1300°C. Processing time: 1st stage annealing for 5 minutes to 12 hours. ■ 1 x 10-8 to 5 x 10'''''Tart (D in vacuum 1- Processing temperature: 1050 to 1300°C. Processing time: All characteristics are to perform second stage annealing within 1 hour. .A method for manufacturing high-silicon iron alloy thin plates with excellent magnetic properties. (2) A high-silicon iron alloy molten metal is formed into a plate material by an ultra-quenching method, and then a thin plate of a desired thickness is formed by rolling multiple times with 1 (b) or intermediate annealing (t) in between. A method for producing a high-silicon iron alloy thin plate with excellent magnetic properties as claimed in claim 1. (3) After the first stage annealing, the second stage annealing is performed continuously without once lowering the temperature to near room temperature. A method for producing a high-silicon iron alloy thin plate with excellent magnetic properties as claimed in claim 1.