JPH0617508B2 - Prevention method of ear crack breakage of electromagnetic steel sheet - Google Patents
Prevention method of ear crack breakage of electromagnetic steel sheetInfo
- Publication number
- JPH0617508B2 JPH0617508B2 JP59072956A JP7295684A JPH0617508B2 JP H0617508 B2 JPH0617508 B2 JP H0617508B2 JP 59072956 A JP59072956 A JP 59072956A JP 7295684 A JP7295684 A JP 7295684A JP H0617508 B2 JPH0617508 B2 JP H0617508B2
- Authority
- JP
- Japan
- Prior art keywords
- steel plate
- laser beam
- steel sheet
- laser
- 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
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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Metal Rolling (AREA)
- Manufacturing Of Steel Electrode Plates (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は電磁鋼板の製造工程において適用されるもので
ある。DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is applied in the manufacturing process of electrical steel sheets.
（従来技術） 電磁鋼板を製造する場合、冷間圧延工程における耳割れ
発生率が高く、生産性を低下させる要因となつている。
特に高Si電磁鋼板においてはその傾向は著しい。従つて
割れ感受性（耳割れ発生率）を下げる必要がある。(Prior Art) When manufacturing an electromagnetic steel sheet, the occurrence rate of edge cracks in the cold rolling process is high, which is a factor that reduces productivity.
This tendency is particularly remarkable in high Si electrical steel sheets. Therefore, it is necessary to lower the cracking susceptibility (ear crack occurrence rate).
そこで従来から熱延電磁鋼板の両縁部分を丸刃によつて
連続剪断（トリミング）することによつて、後続する冷
延工程での耳割れ発生を防止する方法が、採用されてい
る。しかしこの方法は必然的に加工硬化層を伴うこと、
返り、だれなどの形状不良が発生しやすいことや、工具
の損耗に起因する微小亀裂が生じやすいなどの問題点が
あり、そのためトリミング後、さらにこの微小欠陥を除
去する目的で、剪断面をグラインダ等で研磨する方法な
どが行われている。Therefore, conventionally, a method has been adopted in which both edges of the hot rolled electromagnetic steel sheet are continuously sheared (trimmed) with a round blade to prevent the occurrence of edge cracks in the subsequent cold rolling step. However, this method necessarily involves a work-hardened layer,
There are problems such as easy return, sagging and other shape defects, and easy occurrence of microcracks due to tool wear.Therefore, after trimming, the sheared surface is grinded for the purpose of removing these microdefects. The method of polishing with the like is performed.
しかしながらこの方法は機械的な手法であり、微小欠陥
を完全に除去することができない。またSi含有率が増す
と脆化の傾向はさらに助長され、丸刃トリミングおよび
グライダー処理等では耳割れ破断を防止することは出来
ない。However, this method is a mechanical method and cannot completely remove minute defects. Further, as the Si content increases, the tendency of embrittlement is further promoted, and it is not possible to prevent ear crack fracture by round blade trimming and gliding treatment.
一方、電動機、変圧器等の電気機器においては、鉄損の
減少を図る等その特性の向上を図るため電磁鋼板のSi含
有量を増加させることが行われており、従つて耳割れ破
断を防止することが、電磁鋼鉄製造工程における極めて
重要な課題となつている。On the other hand, in electric equipment such as electric motors and transformers, the Si content of electromagnetic steel sheets is increased in order to improve the characteristics such as reduction of iron loss, thus preventing ear crack fracture. This is a very important issue in the electrical steel manufacturing process.
またレーザービームを用いて鋼鉄の端縁物をトリミング
する方法は、例えば特開昭56-163819号公報に開示され
ている。この方法は前記の機械的手法より優れている
が、未だ耳割れを完全に防止し得るには至つていない。A method for trimming steel edge objects using a laser beam is disclosed in, for example, Japanese Patent Laid-Open No. 56-163819. Although this method is superior to the mechanical method described above, it has not yet been able to completely prevent ear cracking.
（発明の目的） 本発明は、このような従来技術の問題点を解決し、Si含
有率の高い電磁鋼板の場合においても、冷間圧延時の耳
割れ破断を防止することを目的とするものである。(Object of the Invention) The present invention aims to solve the problems of the prior art as described above, and to prevent edge cracking during cold rolling even in the case of a magnetic steel sheet having a high Si content. Is.
（発明の構成作用） 本発明は、サイドトリミング後の熱延電磁鋼板の側面に
レーザビームを照射加熱することにより電磁鋼板の耳割
れ破断を防止しようとするもので、エネルギー密度を鋼
板端部の加熱・加工のみに使用するよう処理速度に対し
て、レーザパワーとビーム径を決定して入熱制御したレ
ーザビームを、鋼板端部に照射することにより鋼板端部
の延性を向上させようとするものである。(Constituent action of the invention) The present invention is intended to prevent the edge cracking of the electromagnetic steel sheet by irradiating and heating the side surface of the hot-rolled electromagnetic steel sheet after side trimming with a laser beam. Attempt to improve the ductility of the steel sheet edge by irradiating the steel sheet edge with a laser beam whose heat input is controlled by determining the laser power and beam diameter with respect to the processing speed so that it is used only for heating and processing. It is a thing.
以下図面により本発明を説明する。The present invention will be described below with reference to the drawings.
第１図は本発明方法の要旨を示す説明図、第２図は本発
明方法の実施例を示す説明図である。図において、１は
レーザ発振器、２はレーザビーム、３はビーム形状制御
部、４はレーザビームを鋼板10の両側面11，11′に照射
するために分割するためのビーム分割部、５，５′はレ
ーザ照射ヘツドで、第１図に示すようにその内部に集光
レンズ50を設け、また鋼板の側面11，11′と対向する面
に反射ミラーからなるキヤビテイ51を設けてある。52は
レーザビーム導入孔、53は雰囲気ガス入口、54はキヤビ
テイ冷却水入口、55は同出口である。FIG. 1 is an explanatory diagram showing the gist of the method of the present invention, and FIG. 2 is an explanatory diagram showing an embodiment of the method of the present invention. In the figure, 1 is a laser oscillator, 2 is a laser beam, 3 is a beam shape control unit, 4 is a beam splitting unit for splitting the laser beam to irradiate both side surfaces 11, 11 'of the steel plate 10, 5, 5 Reference numeral ′ is a laser irradiation head, and as shown in FIG. 1, a condenser lens 50 is provided therein, and a cavity 51 formed of a reflection mirror is provided on the surface facing the side surfaces 11 and 11 ′ of the steel plate. 52 is a laser beam introduction hole, 53 is an atmospheric gas inlet, 54 is a cavity cooling water inlet, and 55 is the same outlet.
なおキヤビテイ51の内面は、例えば鏡面仕上げの上に金
メツキを施し、反射率が極めて高い状態にしてある。ま
た６，６′は鋼板10の端面を抑え、鋼板の上下振動を防
止するとともに、鋼板端面から外れたレーザビームを反
射させ、鋼板端面に導くテーパーロールである。７は押
えロール、８は回転計（速度計）である。The inner surface of the cavity 51 is, for example, mirror-finished with gold plating so that the reflectance is extremely high. Further, 6 and 6 ′ are taper rolls that suppress the end face of the steel plate 10 to prevent vertical vibration of the steel plate and reflect the laser beam deviated from the end face of the steel plate to guide it to the end face of the steel plate. Reference numeral 7 is a presser roll, and 8 is a tachometer (speedometer).
本発明方法を実施するには、先ず鋼板10のライン速度ｖ
を速度計８により測定し、鋼板厚さｄと加熱温度Ｔと効
率ηとによつてレーザ発振器１の出力を制御する。レー
ザビーム２は長距離伝送において性能を確保するため
に、ビーム形状制御部３によりビーム径および発散角を
調節した後、ビーム分割部４によつて２分割され、レー
ザ照射ヘツド５，５′に供給される。そこでレーザビー
ム２を照射すれば、該ビーム２は照射ヘツド５内のレン
ズ50により集光され、キヤビテイ51に設けたレーザビー
ム導入孔52を介して鋼板10の側面11に照射される。同様
に鋼板10のもう一方の端面11′には、レーザ照射ヘツド
５′からレーザビームが照射される。In order to carry out the method of the present invention, first, the line speed v of the steel plate 10
Is measured by a speedometer 8, and the output of the laser oscillator 1 is controlled by the steel plate thickness d, the heating temperature T, and the efficiency η. In order to ensure the performance in long-distance transmission, the laser beam 2 is adjusted by the beam shape control unit 3 to adjust the beam diameter and divergence angle, and then is divided into two by the beam dividing unit 4 into laser irradiation heads 5 and 5 '. Supplied. When the laser beam 2 is irradiated there, the beam 2 is condensed by the lens 50 in the irradiation head 5 and is irradiated to the side surface 11 of the steel plate 10 through the laser beam introduction hole 52 provided in the cavity 51. Similarly, the other end surface 11 'of the steel plate 10 is irradiated with a laser beam from the laser irradiation head 5'.
なお鋼板の端面11，11′におけるレーザビーム径Ｄは、
鋼板の振動幅を考慮して、鋼板の板厚ｄよりもΔｈ大き
く設定する。またレーザビーム導入孔52の大きさを極力
小さくするように、レーザビームの焦点位置は、できる
だけキヤビテイの極点位置になるように光学系を設定す
ることが望ましい。キヤビテイの径と焦点距離が長くと
れる場合は、光学系は不用で平行なレーザビームをキヤ
ビテイ導入孔52に導入するだけでよい。The laser beam diameter D at the end faces 11 and 11 'of the steel plate is
In consideration of the vibration width of the steel plate, it is set to be larger than the plate thickness d of the steel plate by Δh. Further, in order to make the size of the laser beam introduction hole 52 as small as possible, it is desirable to set the optical system so that the focus position of the laser beam is at the pole position of the cavity as much as possible. If the diameter of the cavity and the focal length can be made long, the optical system is unnecessary and only a parallel laser beam needs to be introduced into the cavity introduction hole 52.
レーザビーム２の照射によつて鋼板10の端面11，11′は
加熱されるが、非溶融状態であり、この状態ではレーザ
ビーム特にCO2レーザの波長10.6μｍに対しては反射率
が非常に高く、従つて多くのエネルギーが反射し、キヤ
ビテイ51側に戻つてくる。そこで本発明においては、キ
ヤビテイ51を設けその表面およびテーパーロール６，
６′のテーパー部により、この反射エネルギーを多重反
射させ、再び鋼板側面に導入するようにしているので、
鋼板側面における実効吸収率αeはほぼ１に近い値とな
る。Although the end faces 11 and 11 'of the steel sheet 10 are heated by the irradiation of the laser beam 2, the end faces 11 and 11' are in a non-melting state, and in this state, the reflectance is very high for the laser beam, especially for the wavelength of 10.6 μm of the CO 2 laser. It is high, and accordingly, a lot of energy is reflected and returns to the CAVITY 51 side. Therefore, in the present invention, the cavity 51 is provided and its surface and the taper roll 6,
Since the 6'-tapered portion multiple-reflects this reflected energy and introduces it again to the side surface of the steel plate,
The effective absorption rate αe on the side surface of the steel plate is a value close to 1.
すなわち αe＝α＋（１−α）α＋（１−α）2α＋……≒１ 但しαは鋼板側面の吸収率である。That is, αe = α + (1-α) α + (1-α) 2 α + ... ≈1 where α is the absorptance of the side surface of the steel sheet.
本発明は、このように実効吸収率が高くとれるため、レ
ーザビーム径が大きく、低エネルギー密度状態でも余裕
をもつて均一な加熱を行うことができ、その結果鋼板端
面の延性を改善することができるのである。In the present invention, since the effective absorptance can be set high as described above, the laser beam diameter is large, and it is possible to perform uniform heating with a margin even in a low energy density state, and as a result, it is possible to improve the ductility of the steel plate end surface. You can do it.
第３図(a)(b)(c)は本発明方法による鋼板側面の延性改
善状況（歪取り状況）を、従来法と対比して示す説明図
である。すなわち第３図(a)は鋼板の縁部をロータリー
シヤーでトリミングした後の状態を示すものであるが、
側面に微小欠陥（亀裂）12が脆化部とともに存在してい
る。また第３図(b)は第３図(a)における微小欠陥を、グ
ラインダーにより機械的に除去したものであるのである
が、微小欠陥を完全に除去することはできずわずかに残
つており、それが冷却工程における耳割れ破断の原因と
なる。FIGS. 3 (a), (b) and (c) are explanatory views showing the ductility improvement situation (strain relief situation) on the side surface of the steel sheet by the method of the present invention in comparison with the conventional method. That is, FIG. 3 (a) shows a state after the edge portion of the steel plate is trimmed by the rotary shear,
Minute defects (cracks) 12 are present on the side surface together with the embrittlement portion. Further, FIG. 3 (b) shows the micro defects in FIG. 3 (a) mechanically removed by a grinder, but the micro defects cannot be completely removed, and only a small amount remains. It causes breakage of the ear cracks in the cooling process.
これに対し本発明方法によれば、第３図(c)に示すよう
に、鋼板側面をレーザビームにより加熱処理されるの
で、該部分に延性部13が形成され、その結果微小欠陥が
わずかに存在しても、圧延性を高めることができるので
ある。なおキヤビテイ51内に雰囲気ガス入口53からガス
を供給することができるが、この雰囲気ガスはシールド
ガスの働きを行うとともに、レーザビームの照射による
蒸発物がキヤビテイ内面に付着することを防止する働き
も行う。On the other hand, according to the method of the present invention, as shown in FIG. 3 (c), since the side surface of the steel sheet is heat-treated by the laser beam, the ductile portion 13 is formed in the portion, and as a result, minute defects are slightly generated. Even if it exists, the rolling property can be enhanced. Although gas can be supplied into the cavity 51 from the atmospheric gas inlet 53, this atmospheric gas also functions as a shield gas and also prevents vaporized substances due to laser beam irradiation from adhering to the inner surface of the cavity. To do.
（実施例） 次に本発明の実施例を示す。(Example) Next, the Example of this invention is shown.
出力２ＫＷのCO2レーザを用い、半径３０mmの金メツキ
銅製、水冷のキヤビテイを用い、鋼板端面上でビームス
ポツト径３mmの条件で、板厚２．３mm、Si含有率３．２
％の電磁熱延板に、６m/minの速度で照射し、液体窒素
で約−１６０℃以下にして圧延したところ、レーザ照射
しないものには割れが大きく多く発生したが、レーザ照
射したものは、割れがほとんどなく発生した割れも非常
に小さかつた。Using a CO 2 laser with an output of 2 kW, a gold-plated copper with a radius of 30 mm, and a water-cooled cavity, with a beam spot diameter of 3 mm on the end face of the steel plate, a plate thickness of 2.3 mm and a Si content of 3.2.
% Electromagnetic hot-rolled sheet was irradiated at a speed of 6 m / min and rolled with liquid nitrogen at a temperature of about -160 ° C. or lower. Large cracks occurred in the non-laser-irradiated ones. There were almost no cracks, and the cracks that occurred were very small.
（発明の効果） 以上説明したように本発明においては、鋼板端面での実
効吸収率を高め、効率よく安定したレーザ熱処理を行な
うことができ、冷間圧延での耳割れ破断の発生しない、
熱延鋼板のトリミングプロセスとすることができ、電磁
鋼板製造プロセスの生産性を高めることができる。また
レーザビームの制御も容易になるので、自動化が容易で
ある等その効果は多大である。(Effects of the invention) As described above, in the present invention, the effective absorption rate at the steel plate end face can be increased, and efficient and stable laser heat treatment can be performed, and ear crack rupture does not occur in cold rolling.
The hot rolling steel sheet can be trimmed, and the productivity of the electromagnetic steel sheet manufacturing process can be improved. Further, since the control of the laser beam becomes easy, the automation is easy and its effects are great.
【図面の簡単な説明】 第１図は本発明方法の要旨を示す説明図、第２図は本発
明方法の実施例を示す説明図、第３図は本発明方法と従
来法とにおける電磁鋼板の側面の状態を示す説明図であ
る。 １：レーザー発振器、２：レーザビーム ３：ビーム形状制御部、４：ビーム分割部 5,5′：レーザ照射ヘツド 6,6′：テーパーロール、７：押えロール ８：回転計（速度計）、10：鋼板 11,11′：側面、12：微小欠陥 13：延性部、50：集光レンズ 51：キヤビテイ、52：レーザビーム導入孔 53：雰囲気ガス入口 54：キヤビテイ冷却水入口 55：キヤビテイ冷却水出口BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing the gist of the method of the present invention, FIG. 2 is an explanatory view showing an embodiment of the method of the present invention, and FIG. 3 is an electromagnetic steel sheet in the method of the present invention and a conventional method. FIG. 6 is an explanatory view showing a state of a side surface of the. 1: Laser oscillator, 2: Laser beam 3: Beam shape control unit, 4: Beam splitting unit 5, 5 ': Laser irradiation head 6, 6': Tapered roll, 7: Pressing roll 8: Tachometer (speed meter), 10: Steel plate 11, 11 ': Side surface, 12: Small defect 13: Ductility part, 50: Condenser lens 51: Cavity, 52: Laser beam introduction hole 53: Atmosphere gas inlet 54: Cavity cooling water inlet 55: Cavity cooling water exit
フロントページの続き (56)参考文献 特開 昭49−73357（ＪＰ，Ａ) 特開 昭50−137852（ＪＰ，Ａ) 特開 昭52−140348（ＪＰ，Ａ)Continuation of the front page (56) Reference JP-A-49-73357 (JP, A) JP-A-50-137852 (JP, A) JP-A-52-140348 (JP, A)
Claims (1)
域に、鋼板端面の上下振動を防止するテーパーロールを
設けるとともに、該ロールに対向してレーザ発振装置お
よび反射キャビティを設け、レーザ発振装置からのレー
ザビームを、該鋼板端面における該ビーム径を鋼板板厚
より大きくなるよう設定し、該レーザビームを前記テー
パーロールのテーパー面、および前記反射キャビティに
より多重反射させ、鋼板側面に導入し、該側面を加熱す
ることを特徴とする電磁鋼板の耳割れ破断防止方法。1. A laser oscillating device comprising a taper roll for preventing vertical vibration of an end face of a steel plate in a moving region of a hot-rolled electromagnetic steel plate after side trimming, and a laser oscillating device and a reflection cavity facing the roll. Laser beam from the, the beam diameter at the steel plate end surface is set to be larger than the steel plate thickness, the laser beam is taper surface of the taper roll, and multiple reflection by the reflection cavity, introduced into the steel plate side surface, A method for preventing cracking of an edge of an electromagnetic steel sheet, which comprises heating the side surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59072956A JPH0617508B2 (en) | 1984-04-13 | 1984-04-13 | Prevention method of ear crack breakage of electromagnetic steel sheet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59072956A JPH0617508B2 (en) | 1984-04-13 | 1984-04-13 | Prevention method of ear crack breakage of electromagnetic steel sheet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60218425A JPS60218425A (en) | 1985-11-01 |
| JPH0617508B2 true JPH0617508B2 (en) | 1994-03-09 |
Family
ID=13504338
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59072956A Expired - Lifetime JPH0617508B2 (en) | 1984-04-13 | 1984-04-13 | Prevention method of ear crack breakage of electromagnetic steel sheet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0617508B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0226218B1 (en) * | 1985-12-18 | 1993-07-14 | Canon Kabushiki Kaisha | Liquid crystal device |
| US6045636A (en) * | 1997-05-15 | 2000-04-04 | General Motors Corporation | Method for sliver elimination in shearing aluminum sheet |
| CN104399749B (en) * | 2014-10-28 | 2016-06-22 | 武汉钢铁(集团)公司 | A kind of can prevent Si >=3.5% silicon steel limit from splitting and the cold rolling process of brittle failure |
| CN107636175A (en) * | 2015-01-09 | 2018-01-26 | 伊利诺斯工具制品有限公司 | For being heat-treated the system and method based on laser in column of continuous product |
| CN112893466A (en) * | 2021-01-19 | 2021-06-04 | 太原理工大学 | Method for rolling ultrathin strip based on laser energy field assistance |
| JP2023148349A (en) * | 2022-03-30 | 2023-10-13 | 東静工業株式会社 | Metal material heat treatment method and metal material heat treatment equipment |
| WO2024127063A1 (en) * | 2022-12-14 | 2024-06-20 | Arcelormittal | Side trimming method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5147423B2 (en) * | 1972-11-15 | 1976-12-15 | ||
| JPS50137852A (en) * | 1974-04-23 | 1975-11-01 | ||
| JPS52140348A (en) * | 1976-05-19 | 1977-11-22 | Hitachi Ltd | Optical device for photo-processing |
-
1984
- 1984-04-13 JP JP59072956A patent/JPH0617508B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60218425A (en) | 1985-11-01 |
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