JPS6196033A - Method for hot rolling grain-oriented electrical steel slab - Google Patents
Method for hot rolling grain-oriented electrical steel slabInfo
- Publication number
- JPS6196033A JPS6196033A JP21523484A JP21523484A JPS6196033A JP S6196033 A JPS6196033 A JP S6196033A JP 21523484 A JP21523484 A JP 21523484A JP 21523484 A JP21523484 A JP 21523484A JP S6196033 A JPS6196033 A JP S6196033A
- Authority
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- Japan
- Prior art keywords
- hot rolling
- slab
- rolling
- equation
- electrical steel
- Prior art date
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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
- C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
- C21D8/1222—Hot rolling
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- 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)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、発電機、変圧器、鑞動機等の電気機器に使用
される高磁束密度、低鉄損、高81方向性電磁鋼板の製
造に関するものである。Detailed Description of the Invention (Field of Industrial Application) The present invention is directed to the production of high magnetic flux density, low iron loss, and high 81 grain-oriented electrical steel sheets used in electrical equipment such as generators, transformers, and soldering machines. It is related to.
(従来の技術)
方向性電磁鋼板は、磁気特性に優れているため近年使用
量が伸びつつあるが、品質的にも一層の高級化が要求さ
れ、そのため最近では、Sn 、 Cu。(Prior Art) Grain-oriented electrical steel sheets have been used in increasing quantities in recent years because of their excellent magnetic properties, but there is also a demand for higher quality, and for this reason, recently, Sn, Cu, etc. have been used.
Sb、Se、Mo 等の元素の添加に加え、s1含有
量を増加させ磁気特性をさ、らに向上させる方策がとら
れている(例えば特開昭58−217630号公報、特
公昭57−9419号公報など。)。In addition to adding elements such as Sb, Se, and Mo, measures have been taken to further improve magnetic properties by increasing the s1 content (for example, Japanese Patent Application Laid-Open No. 58-217630, Japanese Patent Publication No. 57-9419). Publications, etc.).
ところで、従来、一般に使用されている方向性電磁鋼板
の81含有量は3チ未満であり、しがもSn。By the way, the 81 content of grain-oriented electrical steel sheets that have been conventionally and generally used is less than 3 Ti, but Sn.
Cu、 Sb、 Se、 Mo等が添加されていなかっ
たため、溶体化とスラブの熟熱とが十分に行われている
か否かによって、スラブ加熱時のスラブ表面温度を決定
しても、その後の熱間圧延工程において割れは生じなか
った。Since Cu, Sb, Se, Mo, etc. were not added, even if the slab surface temperature at the time of slab heating was determined, the subsequent heat No cracks occurred during the rolling process.
しかしながら前記のように、電磁鋼板の高性能化、高品
質化のために81含有量が増加し、またSn。However, as mentioned above, in order to improve the performance and quality of electrical steel sheets, the 81 content has increased, and the Sn content has increased.
Cu、 Sb、 Se、 Mo等が株化されると、これ
らの添加元素との相互作用によって必然的に鋼の融点が
低下し、高温に加熱した場合バーニングを生じたり、結
晶粒界で局部的な溶融が生じて、高温強度、延性が低下
する等の現象が起9やすく、さらに加熱炉から熱間圧延
工程までの冷却過程で、添加元素が粒界に偏析して、熱
間圧延中にスラブ上面と側面との角部に耳割れがしばし
ば発生する。When Cu, Sb, Se, Mo, etc. are concentrated, the melting point of the steel inevitably decreases due to interaction with these additive elements, and when heated to high temperatures, burning occurs or localized damage occurs at grain boundaries. In addition, during the cooling process from the heating furnace to the hot rolling process, added elements segregate at grain boundaries and cause problems such as a decrease in high-temperature strength and ductility. Edge cracks often occur at the corners of the top and side surfaces of the slab.
このため熱延後、割れの生じた領域を切取る必要があり
、そのため生産性と歩留りの著しい低下を惹起していた
。Therefore, after hot rolling, it is necessary to cut out the cracked area, which causes a significant decrease in productivity and yield.
従って、高品質化のために添加される成分元素の種類、
含有量を考慮したスラブ加熱時のスラブ温度、特にその
表面温度を決定することが操業上極めて重要である。ま
た圧下率も耳割れの発生に関連がある。従って熱間圧延
に際しては割れが発生しない圧下率を設定する必要があ
る。Therefore, the types of component elements added to improve quality,
It is extremely important for operation to determine the slab temperature during slab heating, especially its surface temperature, taking into account the content. The rolling reduction rate is also related to the occurrence of ear cracks. Therefore, during hot rolling, it is necessary to set a rolling reduction rate that does not cause cracks.
(発明が解決しようとする問題点)
本発明は、耳割れの発生を防止する方向性電磁鋼板スラ
ブの熱間圧延方法を提供するものである。(Problems to be Solved by the Invention) The present invention provides a method for hot rolling grain-oriented electrical steel sheet slabs that prevents the occurrence of edge cracks.
(問題点を解決するための手段)
本発明者等は高温高速引張試験機により耳割れ発生のシ
ミュレーション実験を行い、鋼の化学成分、圧延温度と
強度、延性との関係を詳細に調査した結果、前記のよう
に含有するSi、Sn、Cu。(Means for solving the problem) The present inventors conducted a simulation experiment of the occurrence of edge cracking using a high-temperature, high-speed tensile tester, and the results of a detailed investigation of the relationship between the chemical composition of steel, rolling temperature, strength, and ductility. , Si, Sn, and Cu contained as described above.
P、 S、 Sb、 Se、 Mo 等が相互に作用
して加熱時に融点を引下げ、その後の冷却過程で粒界偏
析し、熱間の強度、延性の低下をもたらしていることを
見出した。It was discovered that P, S, Sb, Se, Mo, etc. interact with each other to lower the melting point during heating, and segregate at grain boundaries during the subsequent cooling process, resulting in a decrease in hot strength and ductility.
また鋼の成分と、耳割に発生温度領域(脆化温度域)と
の間に存在する関係、圧延温度と耳割れ発生限界圧下率
との間に存在する関係を定量的に評価することに成功し
た。その結果ある圧延温度において、所定の式により圧
下率を定めることによって、スラブの加熱時のスラブ表
面温度を、以下に説明するように(Ts−2o)℃以上
Ts℃ 以下の温度域に管理することにより、方向性電
磁鋼の熱延時における耳割れを完全に防止し、健全なス
ラブを得ることに成功した。In addition, we will quantitatively evaluate the relationship between the steel components and the temperature range where edge cracking occurs (embrittlement temperature range), and the relationship between rolling temperature and the critical rolling reduction for edge cracking. Successful. As a result, by determining the rolling reduction rate using a predetermined formula at a certain rolling temperature, the slab surface temperature during heating of the slab is controlled within the temperature range of (Ts-2o)°C or higher and Ts°C or lower, as explained below. As a result, we were able to completely prevent edge cracking during hot rolling of grain-oriented electrical steel and successfully obtain a sound slab.
すなわち本発明は、重量比でCO,03〜0.15%、
si 2.0〜5.0%、 Mn 0.01〜1.o
%、 AJLO,Ol −0,05%、SO,01−0
,03%、No001〜0.01%を主成分として含有
し、がっPを003チ以下、さらにSn、 Cu、 S
b、 Se。That is, in the present invention, CO, 03 to 0.15% by weight,
si 2.0-5.0%, Mn 0.01-1. o
%, AJLO,Ol -0,05%, SO,01-0
, 03%, No. 001 to 0.01% as the main component, and contains P of 0.03% or less, as well as Sn, Cu, and S.
b, Se.
MOの−棟または二種以上を各々を03チ以下含有させ
、残部がFeおよび不可避的不純物からなる鋼のスラブ
の熱間圧延前のスラブ加熱時のスラブ表面温度を、(1
)式で定められる(TB−20)℃以上、78℃以下と
し、引続く熱間圧延工程において、930〜1150℃
の圧延温度域で、スラブ表面温度Tと、(2)式で定ま
る関係をもつ1パスあたりの最大圧下率α以下の圧下率
で熱間圧延を行うことにより、熱間圧延時にスラブ側面
部に生じる耳割れの発生を防止することを特徴とするも
のである。但しTs℃は(1)式、αば(2)式で決定
する。The slab surface temperature during slab heating before hot rolling of a steel slab containing 0.3 mm or less of each of two or more types of MO, with the remainder consisting of Fe and unavoidable impurities, is (1
) defined by the formula (TB-20) and 78°C or less, and in the subsequent hot rolling process, the temperature is 930 to 1150°C.
By performing hot rolling in the rolling temperature range of the slab surface temperature T and the maximum rolling reduction rate per pass α, which has the relationship determined by equation (2), It is characterized by preventing the occurrence of ear cracks. However, Ts°C is determined by equation (1), and α is determined by equation (2).
(’rs )
C≦009チ(重量比)の場合
Ts=1539−(586C%C)+20.5C%si
)+6.5 (%Mn 3 + 500 (%P )+
700〔%S’)+5.7C%/VL)+82(%Sn
)+lll[%Cu)+66〔%Sb〕+94〔%se
)+240r%Mo) )C)0.09チ(重量比)の
場合 豐T 8= 1493−(20
,s (%Si)+6.5〔%Mn〕+500(%p
)+ 70o(%S〕+5.7〔%u:] + 82
C%sn)+n1(pcu)+66〔%Sb’l十94
(%Se)+240(%Mo) ) −”・
(1)(α)
α(%)=50−1.02X10−8×(〔%S)/(
%Mn〕)X(4542(’%Si)〔%C)”+89
〔%sn:〕+s5(%cu)+64r%Sb〕+4a
(%5ea)X(T−1200)(T−900)(T−
2200) −−−−・−(2)本発明は、前記
のようにスラブ加熱時におけるその表面温度を、(Ts
−20)℃以上、18℃以下に管理し、さらに熱間圧延
工程において930〜1150℃の圧延温度域で、スラ
ブ表面温度Tと、(2)式で定まる関°係をもつ1パス
あたりの最大圧下率α以下の圧下率で圧延を行うことを
特徴とするものであるが、先ず78℃およびαについて
説明する。('rs) When C≦009chi (weight ratio), Ts=1539-(586C%C)+20.5C%si
)+6.5 (%Mn3+500 (%P)+
700[%S')+5.7C%/VL)+82(%Sn
)+lll[%Cu)+66[%Sb]+94[%se
)+240r%Mo))C)0.09T (weight ratio) 豐T8=1493-(20
,s (%Si)+6.5[%Mn]+500(%p
) + 70o (%S) + 5.7 [%u:] + 82
C%sn)+n1(pcu)+66[%Sb'l194
(%Se)+240(%Mo) ) −”・
(1)(α) α(%)=50-1.02X10-8×([%S)/(
%Mn])X(4542('%Si)[%C)"+89
[%sn:]+s5(%cu)+64r%Sb]+4a
(%5ea)X(T-1200)(T-900)(T-
2200) -----・-(2) As mentioned above, the surface temperature of the slab during heating is adjusted to (Ts
-20)°C or higher and 18°C or lower, and in the rolling temperature range of 930 to 1150°C in the hot rolling process, the slab surface temperature T and per pass have the relationship determined by equation (2). The method is characterized in that rolling is carried out at a rolling reduction less than or equal to the maximum rolling reduction α, and first, 78° C. and α will be explained.
T8 を求めるにあたっては、基本となるそれぞれの
元素の係数を、従来の多元系の鉄合金の非平面状態にお
ける同相線温度の式として用いられる平居式〔(学振第
19委員会−8837、連続鋳造・凝固−30、昭和4
3年9月)溶鋼の凝固時の熱測定からの最小二乗より求
めた式)〕から導き、さらに未知の元素の係数について
は、熱間の強度延性試験結果と、添加元素量との関係か
ら、それぞれの係数を個々に算出して求めることにより
、真の18℃を得ることができる。なおその結果、係数
の値はSnは82、Cuは111、sbは66、Seは
94.Moは240、Pは500、Sは700と、添加
元素、不純物元素(P)とも融点を下げる効果が大きい
ことがわかった。In calculating T8, the coefficients of each basic element are calculated using the Hirai formula [(19th JSPS Committee-8837, continuous Casting/solidification-30, Showa 4
(September 2013))], and the coefficients of unknown elements are derived from the relationship between the hot strength and ductility test results and the amount of added elements. , the true value of 18° C. can be obtained by calculating each coefficient individually. As a result, the coefficient values were 82 for Sn, 111 for Cu, 66 for sb, and 94 for Se. It was found that Mo had a value of 240, P had a value of 500, and S had a value of 700, indicating that both the additive element and the impurity element (P) had a large effect of lowering the melting point.
次にαについて説明する。Next, α will be explained.
本発明者らは、高温高速引張試験により、耳割れ発生の
シミュレーションの実験を行った。高温高速引張試験結
果の一例を第1図に示す。加熱温度は1390℃一定と
した。930℃〜1150℃の温度範囲で、断面収縮率
が約60%以下の値になっていることがわかる。この温
度範囲は実操業における耳割れ発生温度域とほぼ一致し
ている。The present inventors conducted an experiment to simulate the occurrence of edge cracking using a high-temperature, high-speed tensile test. An example of the results of a high-temperature, high-speed tensile test is shown in Figure 1. The heating temperature was kept constant at 1390°C. It can be seen that the cross-sectional shrinkage ratio is approximately 60% or less in the temperature range of 930°C to 1150°C. This temperature range almost coincides with the temperature range where edge cracking occurs in actual operation.
また、本発明者らは、破面観察により、耳割れの冶金的
原因を明らかにした。すなわち、高温加熱により、鋼の
結晶粒界にS、Si、Sn等の添加元素が偏析する。結
晶粒界偏析は、δ相とγ(オーステナイト)相との不純
物の溶解度の差によっ □て助長される。このとき
、粒界近傍に局部的に低融点の領域ができ、粒界が溶融
する。そして圧延により応力が付加されると、結晶粒界
で破壊が生じる。引張試験片の破面と実操業での耳割れ
破面とを比較した結果、割れ機構は同じであることがわ
かった。これらのことから、高温高速引張試験結果を耳
割れ感受性の指標とすることは、極めて妥当性が高いと
判断された。The present inventors also clarified the metallurgical cause of the edge cracking by observing the fracture surface. That is, due to high-temperature heating, additive elements such as S, Si, and Sn segregate at the grain boundaries of steel. Grain boundary segregation is promoted by the difference in solubility of impurities between the δ phase and the γ (austenite) phase. At this time, a region with a low melting point is locally formed near the grain boundaries, and the grain boundaries are melted. When stress is applied by rolling, fracture occurs at grain boundaries. As a result of comparing the fracture surface of the tensile test piece and the edge crack fracture surface in actual operation, it was found that the cracking mechanism was the same. For these reasons, it was judged that it is extremely appropriate to use the high-temperature, high-speed tensile test results as an index of ear cracking susceptibility.
さらに、本発明者らは、高温高速引張試験の結果から、
不純物成分量、圧延温度におけるγ分率等により、粒界
溶融脆化の度合、脆化域の広さが変化することを見出し
、鋼の成分と脆化温度域の上限、下限、幅との間に存在
する関係、及び鋼の成分、圧延温度と断面収縮率との間
に存在する関係を定量的に評価した。Furthermore, based on the results of high-temperature and high-speed tensile tests, the present inventors found that
It was discovered that the degree of grain boundary melt embrittlement and the width of the embrittlement region change depending on the amount of impurity components, the γ fraction at the rolling temperature, etc., and the relationship between the composition of steel and the upper limit, lower limit, and width of the embrittlement temperature range was We quantitatively evaluated the relationships that exist between the two, as well as the relationships that exist between the steel components, rolling temperature, and section shrinkage.
以上の知見より、本発明者らは、鋼の成分、圧延温度と
耳割れ発生限界圧下率との関係を定量化し、(2)式で
表すことに成功した。Based on the above findings, the present inventors have succeeded in quantifying the relationship between the steel components, rolling temperature, and the critical reduction rate for edge cracking, and expressing it using equation (2).
次に、本発明における化学組成の限定理由について説明
する。Next, the reason for limiting the chemical composition in the present invention will be explained.
Sl の含有量については、2.0%未満では高い電
磁特性を得られず、また、50%を超えると冷間加工が
難しくなることによる。Regarding the Sl content, if it is less than 2.0%, high electromagnetic properties cannot be obtained, and if it exceeds 50%, cold working becomes difficult.
Cの含有量については、0.03%未満では加熱冷却中
に全く相変態を経なくなり、高い電磁特性を得ることが
難しくなり、0.1%を超えるとγ量が過多になり、や
はり高い電磁特性を得られないことによる。Regarding the content of C, if it is less than 0.03%, no phase transformation will occur during heating and cooling, making it difficult to obtain high electromagnetic properties, and if it exceeds 0.1%, the amount of γ will be excessive, which is still high. This is due to the inability to obtain electromagnetic properties.
Mn の含有量については、0.01%未満ではイン
ヒビターとしての効果が期待できず、1.0チを超える
とMnSを完全に溶体化し、結晶粒内に分散析出させる
ことが難しくなることによる。Regarding the Mn content, if it is less than 0.01%, no effect as an inhibitor can be expected, and if it exceeds 1.0%, it becomes difficult to completely dissolve MnS and disperse and precipitate it within the crystal grains.
Sの含有量については、0.01%未満ではMnSを結
晶粒内に分散析出させることが難しく、0.03チを超
えると完全に溶体化することができないことによる。Regarding the S content, if it is less than 0.01%, it is difficult to disperse and precipitate MnS within the crystal grains, and if it exceeds 0.03%, it cannot be completely solutionized.
Mの含有量については、001%未満ではAQNを結晶
粒内に微細分散析出させることが難しく、005%を超
えるとAlNが析出時に粗大化して、インヒビターとし
ての効果が得られないことによる。Regarding the content of M, if it is less than 0.01%, it is difficult to finely disperse and precipitate AQN within the crystal grains, and if it exceeds 0.05%, AlN becomes coarse during precipitation, making it impossible to obtain the effect as an inhibitor.
Nの′ざ有量についても、0.001%未満ではAlN
を結晶粒内に微細分散析出させることが難しく、001
%を超えるとAlが析出時に粗大化して、インヒビター
としての効果が得られないことKよる。Regarding the amount of N, if it is less than 0.001%, AlN
It is difficult to finely disperse and precipitate 001 in crystal grains.
%, Al will become coarse during precipitation and will not be effective as an inhibitor.
またSn、 Cu、 Sb、 Se、 Mo につい
ては03係以下添加することにより磁性を向上させるこ
とができるが、添加量が0.3 %を超えると、特性は
逆に劣化することになる。またPはo、 03 %を超
えると二次再結晶が不安定となるので、上限を003係
とした。Furthermore, magnetism can be improved by adding Sn, Cu, Sb, Se, and Mo in an amount below 0.3%, but if the amount added exceeds 0.3%, the properties will deteriorate. Further, if P exceeds 0.03%, secondary recrystallization becomes unstable, so the upper limit was set to 0.03%.
また930〜1150℃の圧延温度域で、圧下率を1パ
スあたり50係以下にするのは、この温度域では鋼の組
織がフェライト相とオーステナイト相の混合組織となり
、一度に過度の圧下率で圧下を行うと1両相に導入され
る歪量に著しい差異を生じて割れを惹起するからでめる
。In addition, in the rolling temperature range of 930 to 1150°C, the reason why the reduction rate is set to 50 coefficients or less per pass is because in this temperature range, the structure of the steel becomes a mixed structure of ferrite and austenite phases, so if the reduction rate is too high at one time. This is prohibited because rolling down causes a significant difference in the amount of strain introduced into one and both phases, causing cracks.
このようにしてよ発明においては、スラブ加熱における
スラブ表面温度を(TB−20)℃以上Ts℃以下とし
、さらに930〜1150℃における熱間圧延の最大圧
下率αを(2)式により決定した値以下の値で圧延を行
うことにより、耳割れの発生を完全に防止することがで
きる。In this way, in the present invention, the slab surface temperature during slab heating was set to be at least (TB-20)°C and at most Ts°C, and the maximum rolling reduction α in hot rolling at 930 to 1150°C was determined by equation (2). By rolling at a value below this value, occurrence of edge cracks can be completely prevented.
(実施例) 次に本発明の実施例を示す。(Example) Next, examples of the present invention will be shown.
第1表に示す成分の鋼を溶製し、供試材とした。Steel having the components shown in Table 1 was melted and used as test materials.
この材料について(1)式よりT8を求めると、137
2℃であった。そこで、表面温度が1360℃となるよ
うに加熱したのち、空気中で放冷し、第2表に示す表面
温度で熱間圧延を行った。この結果、930℃〜115
0℃で(2)式により定められる最大圧下率αを上回る
圧下率で熱間圧延した場合は、高い確率で耳割れが生じ
た。一方、(2)式により定められる最大圧下率α以下
の圧下率で熱間圧延した場合は、耳割れは生じなかった
。For this material, T8 is calculated from equation (1) and is 137
The temperature was 2°C. Therefore, after heating to a surface temperature of 1360° C., the specimens were allowed to cool in air and hot rolled at the surface temperatures shown in Table 2. As a result, 930℃~115℃
When hot rolling was carried out at 0° C. with a reduction rate exceeding the maximum reduction rate α determined by equation (2), edge cracking occurred with a high probability. On the other hand, when hot rolling was carried out at a rolling reduction rate equal to or lower than the maximum rolling reduction rate α determined by equation (2), no edge cracking occurred.
第 2 表
(発明の効果)
以上説明したように本発明によれば、Slを2.0〜5
. o %含みかつSn、 Cu、 Sb、 Se、
Mo の一種または二種以上を含む方向性電磁鋼スラ
ブを熱間圧延するにあたり、耳割れの発生を完全に防止
することができる。Table 2 (Effects of the Invention) As explained above, according to the present invention, the Sl is 2.0 to 5.
.. Contains o% and Sn, Cu, Sb, Se,
When hot rolling a grain-oriented electromagnetic steel slab containing one or more types of Mo, occurrence of edge cracks can be completely prevented.
また添加元素の種類によっては、スラブ加熱時にインヒ
ビターの溶体化をより完全に行う必要があり、その際に
は、スラブをより高温で熟熱することが要求される。現
用の加熱炉では、スラブ表面を過熱させずに、スラブ中
心部を熟熱させるだめに、加熱速度を遅くして加熱する
こと、あるいは加熱炉のバーナー配置、管理等に対する
慎重な配慮が不可欠であるが、これらの手段は生産性を
著しく阻害する。Furthermore, depending on the type of added element, it is necessary to more completely dissolve the inhibitor during heating of the slab, and in that case, it is required to heat the slab at a higher temperature. With current heating furnaces, in order to thoroughly heat the center of the slab without overheating the surface of the slab, it is essential to slow down the heating speed, or to pay careful consideration to the burner placement and management of the heating furnace. However, these measures significantly impede productivity.
また、以上の手段を施してもなおスラブ表面過熱は完全
には防止出来ない。しかし、本発明によれば、その過熱
されたスラブでも、引続く熱間圧延工程において、(2
)式を満たす圧延条件を採用することによって、熱延時
の耳割れを防止できる等、その効果は極めて太きい。Moreover, even if the above measures are taken, overheating of the slab surface cannot be completely prevented. However, according to the present invention, even in the superheated slab, (2
) By adopting rolling conditions that satisfy the formula, the effect is extremely large, such as preventing edge cracking during hot rolling.
第1図は高温高速引張試験による試験温度と、延性(断
面収縮率)との関係を示す図表である。
第1図FIG. 1 is a chart showing the relationship between test temperature and ductility (section shrinkage rate) in a high-temperature, high-speed tensile test. Figure 1
Claims (1)
.0%Mn:0.01〜1.0%、Al:0.01〜0
.05%S:0.01〜0.03%、N:0.001〜
0.01%を主成分として含有し、かつPを0.03%
以下、さらにSn、Cu、Sb、Se、Moの一種また
は二種以上の各々を0.3%以下含有させ、残部がFe
および不可避的不純物からなる鋼の熱間圧延前のスラブ
加熱時のスラブ表面温度を、(1)式で定められる(T
_s−20)℃以上T_s℃以下とし、引続く熱間圧延
工程において、930〜1150℃の圧延温度域で、ス
ラブ表面温度Tと(2)式で定まる関係をもつ1パスあ
たりの最大圧下率α以下の圧下率で熱間圧延を行うこと
により、熱間圧延時にスラブ側面部に生じる耳割れの発
生を防止することを特徴とする方向性電磁鋼スラブの熱
間圧延方法。 なおT_s℃は(1)式で決定し、最大圧下率αは(2
)式で決定する。 C≦0.09%(重量比)の場合 T_s=1539−(586〔%C〕+20.5〔%S
i〕+6.5〔%Mn〕+500〔%P〕+700〔%
S〕+5.7〔%Al〕+82〔%Sn〕+111〔%
Cu〕+66〔%Sb〕+94〔%Se〕+240〔%
Mo〕) C>0.09%(重量比)の場合 T_s=1493−(20.5〔%Si〕+6.5〔%
Mn〕+500〔%P〕+700〔%S〕+5.7〔%
Al〕+82〔%Sn〕+111〔%Cu〕+66〔%
Sb〕+94〔%Se〕+240〔%Mo〕)・・・・
・・(1)α(%)=50−1.02×10^−^8×
(〔%S〕/〔%Mn〕)×(4542〔%Si〕〔%
C〕^2+89〔%Sn〕+85〔%Cu〕+64〔%
Sb〕+43〔%Se〕)×(T−1200)(T−9
00)(T−2200)・・・・・・(2)[Claims] C: 0.03-0.15%, Si: 2.0-5 in weight ratio
.. 0%Mn: 0.01-1.0%, Al: 0.01-0
.. 05%S: 0.01~0.03%, N:0.001~
Contains 0.01% as a main component and 0.03% P
Below, 0.3% or less of each of one or more of Sn, Cu, Sb, Se, and Mo is further contained, and the remainder is Fe.
(T
_s-20)℃ or more and T_s℃ or less, and in the subsequent hot rolling process, the maximum rolling reduction per pass has the relationship determined by the slab surface temperature T and equation (2) in the rolling temperature range of 930 to 1150℃. A method for hot rolling grain-oriented electrical steel slabs, characterized in that hot rolling is performed at a rolling reduction of α or lower to prevent edge cracks from occurring on the side surfaces of the slab during hot rolling. Note that T_s℃ is determined by equation (1), and the maximum rolling reduction rate α is (2
) is determined by the formula. When C≦0.09% (weight ratio), T_s=1539-(586[%C]+20.5[%S
i]+6.5[%Mn]+500[%P]+700[%
S]+5.7[%Al]+82[%Sn]+111[%
Cu]+66[%Sb]+94[%Se]+240[%
Mo]) When C>0.09% (weight ratio) T_s=1493-(20.5[%Si]+6.5[%
Mn]+500[%P]+700[%S]+5.7[%
Al]+82[%Sn]+111[%Cu]+66[%
Sb]+94[%Se]+240[%Mo])...
...(1) α (%) = 50-1.02×10^-^8×
([%S]/[%Mn])×(4542[%Si][%
C]^2+89[%Sn]+85[%Cu]+64[%
Sb]+43[%Se])×(T-1200)(T-9
00) (T-2200)...(2)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21523484A JPS6196033A (en) | 1984-10-16 | 1984-10-16 | Method for hot rolling grain-oriented electrical steel slab |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21523484A JPS6196033A (en) | 1984-10-16 | 1984-10-16 | Method for hot rolling grain-oriented electrical steel slab |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6196033A true JPS6196033A (en) | 1986-05-14 |
Family
ID=16668932
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP21523484A Pending JPS6196033A (en) | 1984-10-16 | 1984-10-16 | Method for hot rolling grain-oriented electrical steel slab |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6196033A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100419641B1 (en) * | 1999-04-15 | 2004-02-25 | 주식회사 포스코 | Method for preventing cracks in edge part of grain oriented electrical hot rolled steel sheet |
-
1984
- 1984-10-16 JP JP21523484A patent/JPS6196033A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100419641B1 (en) * | 1999-04-15 | 2004-02-25 | 주식회사 포스코 | Method for preventing cracks in edge part of grain oriented electrical hot rolled steel sheet |
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