JPH0524202B2 - - Google Patents
Info
- Publication number
- JPH0524202B2 JPH0524202B2 JP60185025A JP18502585A JPH0524202B2 JP H0524202 B2 JPH0524202 B2 JP H0524202B2 JP 60185025 A JP60185025 A JP 60185025A JP 18502585 A JP18502585 A JP 18502585A JP H0524202 B2 JPH0524202 B2 JP H0524202B2
- Authority
- JP
- Japan
- Prior art keywords
- heating
- furnace
- slab
- atmosphere
- electromagnetic steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 claims description 36
- 229910000831 Steel Inorganic materials 0.000 claims description 15
- 239000010959 steel Substances 0.000 claims description 15
- 230000006698 induction Effects 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 11
- 238000005096 rolling process Methods 0.000 claims description 3
- 229910000976 Electrical steel Inorganic materials 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 238000002485 combustion reaction Methods 0.000 description 4
- 239000000446 fuel Substances 0.000 description 4
- 238000005098 hot rolling Methods 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 238000005485 electric heating Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 238000000137 annealing Methods 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 238000010926 purge Methods 0.000 description 2
- 238000009849 vacuum degassing Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
- C21D8/1205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties involving a particular fabrication or treatment of ingot or slab
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Manufacturing & Machinery (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing Of Steel Electrode Plates (AREA)
Description
本発明は連続鋳造法により得た一方向性電磁鋼
板製造用電磁鋼スラブ（以下単に電磁鋼スラブと
いう）加熱方法に係り、その目的は加熱時の溶融
スケールの生成を抑えて鉄歩留の向上を図ると共
に成品の表面疵を防止するところにある。
周知の如く一方向性電磁鋼板の製造において
は、一次再結晶粒の正常粒成長を抑制するため
に、MnS、AlN等の析出分散相が用いられてい
る。これらの析出分散相を制御するために、熱延
加熱温度は1250〜1400℃の高温加熱が必要であ
り、そのため、電磁鋼スラブ加熱では、普通の鋼
材と比較して、
(1) 溶損による鉄ロスで歩留低下が大きい。
(2) 各熱炉内の堆積ノロの除去が必要である。
従来の熱延加熱炉内の溶損について述べれば鉄
の融点（1535℃）以下の温度で表面が溶融するの
は、加熱中に電磁鋼スラブ表面が酸化して、Siを
含有する低融点のスケールを形成するからであ
る。
連続鋳造法により得られた電磁鋼スラブの燃料
燃焼炉で1250〜1300℃の間の温度に加熱し、続い
て誘導加熱又は抵抗加熱の如き電気加熱により
1350〜1400℃の間に加熱する方法が特開昭47−
14627号公報で提案されており、この方法により
磁気特性が向上し、又電気加熱方式による急速短
時間加熱により材料の損失が減少することが示さ
れている。
本発明者らは電磁鋼スラブの加熱に電気加熱方
式を採用することについて詳細に検討を行つた。
その結果、雰囲気制御した誘導加熱炉を用いて電
磁鋼スラブの加熱実験を繰り返して、大気中
（O2約20％）で加熱した場合には、スラブ表面温
度が1325℃以上になると、溶融スケールが発生し
て溶損が始まること、および雰囲気中のO2濃度
を10％以下に制御することにより、1375℃の高温
でも溶融スケールが発生しないことを確めた。
第１図は誘導加熱炉で、電磁鋼スラブを加熱し
た場合のスラブ表面温度及び炉内雰囲気中O2濃
度とスラブ酸化減量の関係を示したものである。
即ち、電磁鋼スラブ加熱炉として、従来の燃料
燃焼炉では、雰囲気中のO2濃度を10％以下に制
御することは困難であるが、誘導加熱等の電気加
熱法を用いた炉では雰囲気制御が容易で、MnS、
AlN等のインヒビターを完全に固溶させる温度
条件下で、溶融スケールの発生をより完全に防止
することが可能となつた。
本発明において対象とする加熱方式としては、
前掲の特開昭47−14627号公報記載の燃料燃焼炉
と誘導加熱炉との組合せにより、燃料燃焼炉では
1250℃までの加熱を行い、誘導加熱炉では1250〜
1400℃の加熱を行うことが好ましい。本発明にお
いてはこの誘導加熱炉で、表面温度が1325℃以上
となる高温に加熱する場合に、その雰囲気中の
O2濃度を10％以下に抑えるものである。
以下実施例を説明する。
実施例 １
転炉で溶製し、真空脱ガス装置で脱ガスおよび
成分微調整を行つたC0.04％、Si3.19％、Mn0.06
％、S0.02％の鍋下成分の溶鋼を250mm厚電磁鋼ス
ラブに連続鋳造し、鋳造完了後、1250℃に設定し
た燃料燃焼加熱炉に装入した。1250℃に均熱され
た電磁鋼スラブを更にN2ガスパージによりO2量
を10％以下に雰囲気制御した誘導加熱炉に装入
し、急速加熱をして、表面温度1350℃×30分の均
熱をさせた後、熱延を行つた。その他の電磁鋼ス
ラブはそのままの状態で、従来方式の燃料燃焼加
熱炉に装入し、1350℃に均熱した後、熱延を行つ
た。これらのホツトコイルを中間焼鈍を含む２回
圧延法工程で通板し、板厚0.30mmの成品とした結
果を第１表に示す。
The present invention relates to a heating method for electrical steel slabs (hereinafter simply referred to as electrical steel slabs) for producing unidirectional electrical steel sheets obtained by continuous casting, and its purpose is to suppress the formation of molten scale during heating and improve iron yield. The objective is to prevent surface flaws on the finished product. As is well known, in the production of unidirectional electrical steel sheets, precipitated dispersed phases such as MnS and AlN are used to suppress normal grain growth of primary recrystallized grains. In order to control these precipitated dispersed phases, high-temperature heating of 1250 to 1400°C is required for hot rolling. Therefore, compared to ordinary steel materials, heating of electrical steel slabs reduces (1) Yield decreases significantly due to iron loss. (2) It is necessary to remove the accumulated slag inside each thermal furnace. Regarding melting damage in conventional hot-rolling heating furnaces, the reason why the surface melts at temperatures below the melting point of iron (1535℃) is due to the oxidation of the surface of the electrical steel slab during heating, which causes the melting of low-melting-point materials containing Si. This is because it forms a scale. Electrical steel slabs obtained by continuous casting are heated in a fuel combustion furnace to a temperature between 1250 and 1300°C, followed by electrical heating such as induction heating or resistance heating.
A method of heating between 1350 and 1400℃ was published in 1972.
This method was proposed in Japanese Patent No. 14627, and it has been shown that this method improves magnetic properties and reduces material loss due to rapid short-time heating using an electric heating method. The present inventors conducted a detailed study on employing an electric heating method for heating electromagnetic steel slabs.
As a result, we repeatedly conducted heating experiments on electromagnetic steel slabs using an atmosphere-controlled induction heating furnace, and found that when heated in the atmosphere (approximately 20% O2 ), when the surface temperature of the slab exceeded 1325°C, melting scale occurred. It was confirmed that molten scale occurs even at a high temperature of 1375°C by controlling the O 2 concentration in the atmosphere to 10% or less. FIG. 1 shows the relationship between slab surface temperature, O 2 concentration in the furnace atmosphere, and slab oxidation loss when a magnetic steel slab is heated in an induction heating furnace. In other words, it is difficult to control the O 2 concentration in the atmosphere to 10% or less with a conventional fuel-burning furnace as an electromagnetic steel slab heating furnace, but with a furnace that uses electric heating methods such as induction heating, it is difficult to control the O 2 concentration in the atmosphere to below 10%. is easy, MnS,
Under temperature conditions that completely dissolve inhibitors such as AlN, it has become possible to more completely prevent the occurrence of melted scale. The heating method targeted in the present invention is as follows:
By combining the fuel combustion furnace and induction heating furnace described in the above-mentioned Japanese Patent Application Laid-Open No. 47-14627, the fuel combustion furnace
Heating is performed up to 1250℃, and in induction heating furnace it is heated up to 1250℃.
Preferably, heating is performed at 1400°C. In the present invention, when heating to a high temperature such that the surface temperature is 1325°C or higher in this induction heating furnace, the temperature in the atmosphere is
This suppresses the O 2 concentration to 10% or less. Examples will be described below. Example 1 C0.04%, Si3.19%, Mn0.06 melted in a converter, degassed in a vacuum degassing device, and fine-tuned the components.
%, S0.02% of the molten steel was continuously cast into a 250 mm thick electromagnetic steel slab, and after the casting was completed, it was charged into a fuel-fired heating furnace set at 1250°C. The electromagnetic steel slab soaked to 1250°C is further charged into an induction heating furnace whose atmosphere is controlled to keep the O 2 content below 10% by N 2 gas purge, and rapidly heated to a surface temperature of 1350°C x 30 minutes. After heating, hot rolling was performed. The other electromagnetic steel slabs were charged as-is into a conventional fuel-fired heating furnace, heated to 1,350°C, and then hot-rolled. These hot coils were passed through a two-step rolling process including intermediate annealing to produce products with a thickness of 0.30 mm, and the results are shown in Table 1.
【表】
実施例 ２
転炉で溶製し、真空脱ガス装置で脱ガスおよび
成分調整を行つたC0.05％、Si3.13％、Mn0.07％、
S0.02％の鍋下成分の溶鋼を250mmの厚電磁鋼スラ
ブに連続鋳造し、鋳造完了後、1250℃に設定した
燃料燃焼炉に装入し、1250℃に均熱された電磁鋼
スラブを更にN2ガスパージによりO2量を１％以
下に雰囲気制御した誘導加熱炉に装入し、急速加
熱をして、表面温度1370℃×30分の均熱をさせた
後、熱延を行つた。残りの電磁鋼スラブは、従来
方式の燃料燃焼加熱炉に装入し、1350℃に均熱し
た後、熱延を行つた。これらのホツトコイルを中
間焼鈍を含む２回圧延法工程で通板し、板厚0.30
mmの成品とした結果を第２表に示す。[Table] Example 2 C0.05%, Si3.13%, Mn0.07%, melted in a converter, degassed and component adjusted in a vacuum degassing device,
Molten steel with a bottom component of S0.02% is continuously cast into a 250mm thick electromagnetic steel slab, and after the casting is completed, it is charged into a fuel combustion furnace set at 1250℃, and the electromagnetic steel slab is soaked at 1250℃. Furthermore, it was charged into an induction heating furnace in which the atmosphere was controlled to have an O 2 content of 1% or less by N 2 gas purge, and after rapid heating and soaking for 30 minutes at a surface temperature of 1370°C, hot rolling was performed. . The remaining electrical steel slabs were charged into a conventional fuel-fired heating furnace, heated to 1350°C, and then hot-rolled. These hot coils were passed through a two-step rolling process including intermediate annealing to a thickness of 0.30.
Table 2 shows the results for products of mm.
【表】
上記実施例１及び２からも明らかな様に、本発
明方法により鉄歩留ロス及び磁性共に良好な結果
が得られた。[Table] As is clear from Examples 1 and 2 above, the method of the present invention yielded good results in both iron yield loss and magnetism.
第１図は誘導加熱炉で電磁鋼スラブを加熱した
場合のスラブ表面温度及び炉内雰囲気中O2濃度
とスラブ酸化減量の関係を示したものである。
Figure 1 shows the relationship between slab surface temperature, O 2 concentration in the furnace atmosphere, and slab oxidation weight loss when a magnetic steel slab is heated in an induction heating furnace.
Claims (1)
の温度に加熱後圧延する方法において、スラブ表
面温度が1325℃以上の高温域の加熱を、雰囲気中
のO2濃度を10％以下に調整した誘導加熱炉によ
り行うことを特徴とする電磁鋼スラブの加熱方
法。1 Continuously cast electromagnetic steel slab at 1250-1400℃
An electromagnetic steel slab characterized in that the heating in the high temperature range of 1325°C or higher on the surface of the slab is performed in an induction heating furnace in which the O 2 concentration in the atmosphere is adjusted to 10% or less, in the method of rolling after heating to a temperature of heating method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18502585A JPS6169924A (en) | 1985-08-24 | 1985-08-24 | Method for heating electromagnetic steel slab |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18502585A JPS6169924A (en) | 1985-08-24 | 1985-08-24 | Method for heating electromagnetic steel slab |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15396481A Division JPS5858228A (en) | 1981-09-30 | 1981-09-30 | Heating method for electrical steel slab |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6169924A JPS6169924A (en) | 1986-04-10 |
| JPH0524202B2 true JPH0524202B2 (en) | 1993-04-07 |
Family
ID=16163461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18502585A Granted JPS6169924A (en) | 1985-08-24 | 1985-08-24 | Method for heating electromagnetic steel slab |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6169924A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2563695B2 (en) * | 1991-08-12 | 1996-12-11 | 新日本製鐵株式会社 | Method of heating grain-oriented electrical steel slabs |
| JPH06212247A (en) * | 1993-01-11 | 1994-08-02 | Nippon Steel Corp | Method for controlling atmosphere in induction heating furnace |
| JP3240035B2 (en) * | 1994-07-22 | 2001-12-17 | 川崎製鉄株式会社 | Manufacturing method of grain-oriented silicon steel sheet with excellent magnetic properties over the entire coil length |
-
1985
- 1985-08-24 JP JP18502585A patent/JPS6169924A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6169924A (en) | 1986-04-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH0686631B2 (en) | Method for manufacturing unidirectional electrical steel sheet with high magnetic flux density | |
| CN111417737B (en) | Grain-oriented electromagnetic steel sheet with low iron loss and method for producing same | |
| JPS5933170B2 (en) | Method for manufacturing aluminum-containing unidirectional silicon steel sheet with extremely high magnetic flux density | |
| JPS6160895B2 (en) | ||
| JPS5817806B2 (en) | Seizouhou | |
| JPH0524202B2 (en) | ||
| JP4894146B2 (en) | Heating method for grain-oriented electrical steel slab | |
| JP3369443B2 (en) | Manufacturing method of high magnetic flux density unidirectional electrical steel sheet | |
| JPS6242968B2 (en) | ||
| JPS5834531B2 (en) | Method for manufacturing non-oriented silicon steel sheet with excellent magnetic properties | |
| JP2815904B2 (en) | Heating method and heating furnace for slab for oriented silicon steel | |
| JPS63109115A (en) | Production of grain oriented silicon steel sheet having good electromagnetic characteristic | |
| JPS5832214B2 (en) | Method for manufacturing unidirectional silicon steel sheet with extremely high magnetic flux density and low iron loss | |
| JPS6210213A (en) | Production of grain oriented silicon steel sheet having good electromagnetic characteristic | |
| JPS6237688B2 (en) | ||
| JPH0699751B2 (en) | Method for producing grain-oriented silicon steel sheet having good electromagnetic characteristics | |
| KR20240098917A (en) | Method for manufacturing non-oriented electrical steel sheet | |
| JP2533987B2 (en) | Hot rolling method for continuous cast slab for unidirectional electrical steel sheet. | |
| JPH0657854B2 (en) | Method of heating grain-oriented silicon steel slab | |
| JPH0726156B2 (en) | Method for producing grain-oriented electrical steel sheet with excellent magnetic properties and surface properties | |
| JPH066747B2 (en) | Method for producing unidirectional silicon steel sheet having high magnetic flux density and low iron loss | |
| JPH0663032B2 (en) | Method for producing grain-oriented silicon steel sheet having good magnetic properties and surface properties | |
| JPH0689406B2 (en) | Method for producing grain-oriented silicon steel sheet having good magnetic properties | |
| JP4214739B2 (en) | Method for producing non-oriented electrical steel sheet | |
| JPS6169927A (en) | Method for heating continuous casting slab of single orientation electro magnetic steel |