JPS5815525B2 - Improvements in electrical steel - Google Patents
Improvements in electrical steelInfo
- Publication number
- JPS5815525B2 JPS5815525B2 JP49109865A JP10986574A JPS5815525B2 JP S5815525 B2 JPS5815525 B2 JP S5815525B2 JP 49109865 A JP49109865 A JP 49109865A JP 10986574 A JP10986574 A JP 10986574A JP S5815525 B2 JPS5815525 B2 JP S5815525B2
- Authority
- JP
- Japan
- Prior art keywords
- steel
- concentration
- silicon
- cold
- cold rolled
- 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
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
-
- 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
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Thermal Sciences (AREA)
- Electromagnetism (AREA)
- Soft Magnetic Materials (AREA)
- Manufacturing Of Steel Electrode Plates (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Treatments Of Macromolecular Shaped Articles (AREA)
Description
【発明の詳細な説明】
本発明は電磁器機用鋼、すなわち電気機械の磁気回路形
成用鋼の製造に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the production of steel for electromagnetic equipment, ie for forming magnetic circuits in electrical machines.
本発明は特に導電度を減小しかつ鋼にその他の望ましい
性質を与えるため故意に珪素を接種しない電気用鋼に関
し、これにより鋼が励磁されたとき生ずる渦流等による
損失を防止するものである。The invention particularly relates to electrical steels that are not intentionally inoculated with silicon to reduce conductivity and impart other desirable properties to the steel, thereby preventing losses due to eddy currents and the like that occur when the steel is energized. .
このような無珪素鋼は通例珪素鋼が０．５〜３．２５％
の珪素濃度を有するのに比較して０．０５重量％より低
い珪素濃度を有する。Such silicon-free steel usually has a silicon content of 0.5 to 3.25%.
It has a silicon concentration of less than 0.05% by weight compared to a silicon concentration of less than 0.05% by weight.
一般に電磁器機用鋼は慣例の一般用鋼から製造され、こ
れらは任意基本的酸素、平炉またはその他の製鋼方法に
よって精製され、これらは典型的には炭素濃度０．０５
％まで、リン０．０２５％までを含み、残部は他の付随
的不純物を除℃・ては鉄である。Generally, electromagnetic steels are produced from conventional utility steels, which are refined by any basic oxygen, open hearth or other steelmaking process, and which typically have carbon concentrations of 0.05
%, up to 0.025% phosphorus, the balance being iron, exclusive of other incidental impurities.
このような鋼を平板化および熱間圧延した後、このよう
にして生成されたストリップは冷間圧延され、次に炭素
を許容レベルまで減小するため脱炭焼鈍を行なう。After flattening and hot rolling such steel, the strip thus produced is cold rolled and then decarburized annealed to reduce the carbon to an acceptable level.
この脱炭焼鈍の後、ストリップはほぼ最終ゲージまで冷
間減厚される。After this decarburization annealing, the strip is cold thinned to approximately final gauge.
１欠除間減厚から出たストリップの炭素を減小する脱炭
焼鈍を行なうことはこのようにして生成されるストリッ
プまたはシートの費用を可成り増大する。Performing a decarburizing anneal to reduce carbon in the strip emerging from a one-break thickness reduction considerably increases the cost of the strip or sheet thus produced.
このような価格上の不利は、一部は焼鈍炉へ供給すべき
還元ガスの価格が高いこと、また一部は還元ガス雰囲気
に安全に適合し得る炉が高価なためである。This cost disadvantage is due in part to the high price of the reducing gas that must be fed to the annealing furnace, and in part to the high cost of furnaces that can be safely adapted to the reducing gas atmosphere.
本発明の１つの目的は適当な硬度および磁気的性質を有
し、しかも焼鈍中の脱炭の必要から生ずる欠点のない電
気用鋼を生成することである。One object of the present invention is to produce an electrical steel with suitable hardness and magnetic properties, yet without the drawbacks resulting from the need for decarburization during annealing.
本発明はその最も広範囲の態様によれば、電磁器機用無
珪素鋼の製造方法を提供するものであり、これは慣例の
精製方法から誘導した鋼を真空脱ガス処理して炭素濃度
を０．０２％未満に減小し、脱ガス処理の前、その間ま
たはその後にリン濃度を調節して０．０５〜０．１５％
の範囲内とし、このようにして生成した鋼を中間ゲージ
になるよう熱間および冷間圧延し、冷間圧延した鋼を非
脱炭焼鈍し、焼鈍した鋼をついでその最終ゲージに冷間
圧延することを含むものである。According to its broadest aspect, the present invention provides a method for producing silicon-free steel for electromagnetic equipment, which involves vacuum degassing of steel derived from conventional refining processes to reduce the carbon concentration to 0. 0.02% and adjust the phosphorus concentration before, during or after degassing to 0.05-0.15%
The steel thus produced is hot and cold rolled to intermediate gauge, the cold rolled steel is annealed without decarburization, and the annealed steel is then cold rolled to its final gauge. It includes doing.
真空脱ガスを行われる鋼は任意基本的酸素、平炉精製ま
たはその他の製鉄方法から誘導されたものであり、これ
はマンガンを０．３５〜０．９重量％の範囲で含むこと
が好ましい。The steel to be vacuum degassed is derived from any basic oxygen, open hearth refining or other steelmaking process and preferably contains manganese in the range 0.35 to 0.9% by weight.
マンガン濃度がこの範囲外のときは真空脱ガス処理の前
、その間またはその後に適当な接種により好ましい範囲
内に含まれるよう調節される。If the manganese concentration is outside this range, it is adjusted to within the preferred range by appropriate inoculation before, during or after vacuum degassing.
本発明による典型的の鋼は、脱ガス後、０．００４〜０
．０２％の炭素、０．０４％の酸素、０．３５〜０．９
％のマンガン、および０．０７〜０．１５％のリン、残
部は付随的不純物を除いて鉄を含む。Typical steels according to the invention, after degassing, range from 0.004 to 0.
．． 02% carbon, 0.04% oxygen, 0.35-0.9
% manganese, and 0.07-0.15% phosphorus, the balance containing iron excluding incidental impurities.
鋼の酸化含量は例えば珪素またはアルミニウム等適当な
化学的脱酸剤の添加によって０．０２％より少なくなる
よう更に減小されるが、この場合添加される脱酸剤の量
は鋼中のその濃度が０．０１％を超えるほど増大しては
ならず、また０００５％より大きくないことが好ましい
。The oxidation content of the steel can be further reduced to less than 0.02% by the addition of suitable chemical deoxidizers, such as silicon or aluminum, in which case the amount of deoxidizer added is equal to that in the steel. The concentration should not increase by more than 0.01% and preferably not more than 0.005%.
後続の静的焼鈍によって生ずる硬度の劣化を補償スるの
に有効なことが知られている鋼中のリンは、溶融物中に
導入されるその温度において比較的低い蒸発特性を有す
るフェロフォスフオルの接種によって鋼中に適宜導入さ
れる。Phosphorus in steel, which is known to be effective in compensating for hardness deterioration caused by subsequent static annealing, is a ferrophosphorus compound that has relatively low evaporation properties at the temperature at which it is introduced into the melt. It is suitably introduced into the steel by inoculation with or.
ストリップに冷間減厚された後の鋼は温度６６０〜７０
５℃（１２２０〜１３００’Ｆ）範囲で静的非脱炭焼鈍
されるが、これより高いかまたは低い温度でもよい。The steel after cold thinning into strip has a temperature of 660-70
Static non-decarburizing annealing is performed in the 5°C (1220-1300'F) range, although higher or lower temperatures may be used.
この焼鈍処理は冷間圧延ストリップに輝いた仕−Ｌ面を
残すよう操作され、またこの場合の処理は少量の水素等
の還元性ガスを含む雰囲気中で行われる。The annealing process is operated to leave a bright finish on the cold rolled strip, and the process is carried out in an atmosphere containing a small amount of a reducing gas such as hydrogen.
光輝仕上非脱炭焼鈍に適当なガスは例えば約４容積％の
水素を含む窒素である。A suitable gas for bright non-decarburizing annealing is, for example, nitrogen containing about 4% by volume hydrogen.
本発明に用いられる熱間および冷間圧延のパラメータは
無珪素電気鋼製造技術に慣例的に用いられるものである
。The hot and cold rolling parameters used in the present invention are those conventionally used in silicon-free electrical steel manufacturing technology.
典型的には鋼は仕上温度８４３〜１０１０℃（１，５５
０〜１８５０下）にて熱間圧延され、次いで非脱炭焼鈍
の前に最終ゲージの５〜１５％以内に１欠除間圧延され
る。Typically, steel has a finishing temperature of 843-1010°C (1,55°C).
0-1850 below) and then one-break rolling to within 5-15% of final gauge before non-decarburizing annealing.
本発明の１実施例においては基本的酸素精製法から誘導
された鋼はアンキルド状態で転炉からし一ドル中に注入
される。In one embodiment of the invention, the steel derived from the basic oxygen refining process is poured into a converter mustard in an unkilled state.
この段階において鋼は典型的には炭素０．０２〜０．０
７重量％および酸素０．０４〜０．１４％、残部は個々
の精製工程に付随するその他の不純物を除き鉄である。At this stage the steel typically has 0.02 to 0.0 carbon
7% by weight and 0.04-0.14% oxygen, the balance being iron excluding other impurities associated with the individual purification steps.
レードル中にある間に、鋼はフェロフォスフオル形状の
リンを接種され、かつその量は溶融物のリン濃度を約０
．１０％に上昇するに充分なものとする。While in the ladle, the steel is inoculated with phosphorus in the form of ferrophosphorus, and the amount reduces the phosphorus concentration of the melt to about 0.
．． 10%.
じ−ドルから鋼は真空脱ガス装置に導入され、減圧下で
炭素濃度を００２％より低くする。The steel is then introduced into a vacuum degasser to reduce the carbon concentration to less than 0.02% under reduced pressure.
真空脱ガス中同じ（減小される溶融物の酸素濃度はアル
ミニウム等の化学的脱酸剤の加用によって更に低下され
、この量は最終アルミニウム濃度、すなわち０．０１％
を超えず、特に０．００５％を超えないことを良好とす
る濃度を与えるに有効なものである。During vacuum degassing the oxygen concentration of the melt (which is reduced) is further reduced by the addition of a chemical deoxidizer such as aluminum, and this amount is equal to the final aluminum concentration, i.e. 0.01%.
It is effective in providing a concentration that does not exceed 0.005%, particularly 0.005%.
同様真空Ｆで行なうことを良好とする化学的脱酸中、残
留遊離酸素はアルミナに変換され、これは真空処理自体
によって誘起される溶融物中の乱流を利用する浮遊選別
によって溶融物から除去される。During chemical deoxidation, which is also preferably carried out in a vacuum F, residual free oxygen is converted to alumina, which is removed from the melt by flotation using turbulence in the melt induced by the vacuum process itself. be done.
化学的脱酸後の典型的最終酸素濃度は０００２〜０．０
３％である。Typical final oxygen concentration after chemical deoxidation is 0002-0.0
It is 3%.
もし要すればこの段階で鋼溶融物にマンガンを、特にな
お真空下で添加し、マンカン濃度を約０．６５％に上昇
するが、マンガンはリンと共に工程の任意他の適当な段
階で鋼に添加してもよい。If required, manganese may be added to the steel melt at this stage, especially still under vacuum, to raise the manganese concentration to about 0.65%, but manganese can be added to the steel together with phosphorus at any other suitable stage of the process. May be added.
上記のようにして生成された鋼はバッチ方式でインゴッ
トに鋳造されるか、または連続的に適当な」法の板に鋳
造される。The steel produced as described above can be cast into ingots in batch mode or continuously into plates in a suitable manner.
１２１０〜１３３０℃（２２００〜２４００”Ｆ）範囲
で最小限３時間再熱後、板はストリップに熱間圧延され
、これは８４３〜１０１０°Ｃ（１５５０〜１．８５０
”Ｆ ）で仕上圧延される。After reheating for a minimum of 3 hours in the 1210-1330°C (2200-2400"F) range, the plate is hot rolled into strips, which
Finish rolling is performed at ``F''.
＝般に１９〜２．１ ｍｍの厚さを有する熱間圧延スト
リップは次に冷間圧延されて仕上げゲージより約６〜８
％（好ましくは伸ばして測った場合７％）大きくする。= The hot rolled strip, generally having a thickness of 19 to 2.1 mm, is then cold rolled to a finish gauge of about 6 to 8 mm.
% (preferably 7% when measured stretched).
冷間圧延された中間ストリップは温度６６０〜７０５℃
（１２２０〜１３００’Ｆ）に維持された箱焼鈍炉中で
非脱炭焼鈍を行なう。Cold rolled intermediate strip temperature 660~705℃
Non-decarburizing annealing is performed in a box annealing furnace maintained at (1220-1300'F).
ストリップはＨＮＸと称せられるガス雰囲気中で約４時
間この温度に保持され、前記ＨＮＸは４％の水素と９６
％の窒素を含み、これはコイルの光輝ある表面仕上を保
持するのに有効である。The strip is held at this temperature for about 4 hours in a gas atmosphere called HNX, which contains 4% hydrogen and 96
% nitrogen, which is effective in preserving the shiny surface finish of the coil.
冷却後、コイルは最終ゲージに冷間厚され、使用への準
備が出来る。After cooling, the coil is cold thickened to final gauge and ready for use.
使用にお℃・ては、コイルはポンチ、切断またはその他
の機械的加工により薄板とし、これを積重ねて電気機械
の磁心を形成する。In use, the coils are punched, cut or otherwise mechanically formed into thin sheets which are stacked to form the magnetic core of the electrical machine.
この段階で薄板またはその他の成形片は磁性を改善する
ためこの技術で公知の任意操作によって脱炭焼鈍される
。At this stage, the sheet or other shaped piece is decarburized and annealed by any procedure known in the art to improve its magnetic properties.
本発明によって製造された鋼は冷間減厚に先立つ熱間圧
延ス） ＩＪツブの脱炭、または冷間減厚に続く連続炉
中の脱炭焼鈍の℃・ずれかを含む工程ルートによって従
来得られたものに等しい物理的性質を有することが解っ
た。The steel produced in accordance with the present invention can be manufactured by a process route that involves either hot rolling prior to cold thinning, decarburization of the IJ tube, or decarburization annealing in a continuous furnace following cold thinning. It was found to have physical properties equivalent to those obtained.
更に珪素添加物がないにもかかわらず、これらの鋼は、
これらの工程ルートを受けた珪素鋼（２％以１・゛の珪
素レベルを有するもの）よりもすぐれた磁性を有してい
る。Furthermore, despite the lack of silicon additives, these steels
It has superior magnetic properties to silicon steels that have undergone these process routes (those with silicon levels of 2% or more and 1.5%).
次の表は本発明によって処理された２種の異なるゲージ
の典型的な鋼を、慣例方法によって、即ち、本明細書頭
初に述べたルートによって処理された無珪素鋼と比較し
たものである。The following table compares typical steels of two different gauges treated according to the present invention with silicon-free steels treated by conventional methods, i.e. by the route mentioned at the beginning of this specification. .
本発明の主題である鋼の磁性および硬度の典型的数値お
よび慣例の鋼の磁性および硬度の典型的数値は次の通り
である。Typical values for the magnetism and hardness of the steels that are the subject of the present invention and typical values for the magnetism and hardness of conventional steels are as follows.
Claims (1)
て炭素濃度０．０２重量％未満に減少し、脱ガス処理の
前、その間またはその後にリン濃度を調節して０．０５
〜０．１５％の範囲内とし、このようにして生成した鋼
を中間ゲージとなるよう熱間および冷間圧延し、冷間圧
延した鋼を非脱炭焼純し、焼鈍した鋼をついでその最終
ゲージに冷間圧延することを含む、電磁器機用無珪素鋼
の製造方法。1 Steel derived from conventional refining processes is vacuum decased to reduce the carbon concentration to less than 0.02% by weight and the phosphorus concentration is adjusted to 0.05% before, during or after degassing.
~0.15%, the steel thus produced is hot and cold rolled to intermediate gauge, the cold rolled steel is non-decarburized annealed, and the annealed steel is then subjected to its final A method of manufacturing silicon-free steel for electromagnetic equipment, comprising cold rolling into a gauge.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB4470273 | 1973-09-24 | ||
| GB4470273A GB1478112A (en) | 1973-09-24 | 1973-09-24 | Electrical steels |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5077212A JPS5077212A (en) | 1975-06-24 |
| JPS5815525B2 true JPS5815525B2 (en) | 1983-03-26 |
Family
ID=10434391
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP49109865A Expired JPS5815525B2 (en) | 1973-09-24 | 1974-09-24 | Improvements in electrical steel |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS5815525B2 (en) |
| BE (1) | BE820233A (en) |
| CA (1) | CA1030851A (en) |
| DE (1) | DE2445358A1 (en) |
| FR (1) | FR2244824B1 (en) |
| GB (1) | GB1478112A (en) |
| IT (1) | IT1020847B (en) |
| NO (1) | NO144221C (en) |
| SE (1) | SE421324B (en) |
| ZA (1) | ZA745862B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU533226B2 (en) * | 1979-03-21 | 1983-11-10 | British Steel Corp. | Non-silicon electromagnetic steel (non-aging) |
| US4306922A (en) * | 1979-09-07 | 1981-12-22 | British Steel Corporation | Electro magnetic steels |
| GB8324986D0 (en) * | 1983-09-19 | 1983-10-19 | British Steel Corp | Electrical steels |
| US4695318A (en) * | 1986-10-14 | 1987-09-22 | Allegheny Ludlum Corporation | Method of making steel |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1437673A (en) * | 1965-03-26 | 1966-05-06 | Loire Atel Forges | Method of manufacturing steel products for magnetic uses without preferential crystalline orientation |
| DE1931420B1 (en) * | 1969-06-20 | 1971-04-22 | Hoesch Ag | Use of a steel that has been vacuum-treated in the liquid state as a dynamo tape |
-
1973
- 1973-09-24 GB GB4470273A patent/GB1478112A/en not_active Expired
-
1974
- 1974-09-16 ZA ZA00745862A patent/ZA745862B/en unknown
- 1974-09-19 CA CA209,606A patent/CA1030851A/en not_active Expired
- 1974-09-20 NO NO743393A patent/NO144221C/en unknown
- 1974-09-23 SE SE7411914A patent/SE421324B/en not_active IP Right Cessation
- 1974-09-23 BE BE148803A patent/BE820233A/en not_active IP Right Cessation
- 1974-09-23 IT IT69859/74A patent/IT1020847B/en active
- 1974-09-23 DE DE19742445358 patent/DE2445358A1/en not_active Ceased
- 1974-09-24 FR FR7432133A patent/FR2244824B1/fr not_active Expired
- 1974-09-24 JP JP49109865A patent/JPS5815525B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| BE820233A (en) | 1975-01-16 |
| CA1030851A (en) | 1978-05-09 |
| IT1020847B (en) | 1977-12-30 |
| SE7411914L (en) | 1975-03-25 |
| FR2244824A1 (en) | 1975-04-18 |
| NO144221C (en) | 1981-07-29 |
| DE2445358A1 (en) | 1975-04-03 |
| GB1478112A (en) | 1977-06-29 |
| NO144221B (en) | 1981-04-06 |
| ZA745862B (en) | 1975-09-24 |
| AU7357174A (en) | 1976-03-25 |
| NO743393L (en) | 1975-04-21 |
| SE421324B (en) | 1981-12-14 |
| FR2244824B1 (en) | 1979-07-20 |
| JPS5077212A (en) | 1975-06-24 |
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