JP2003013190A - High-grade non-oriented magnetic steel sheet - Google Patents
High-grade non-oriented magnetic steel sheetInfo
- Publication number
- JP2003013190A JP2003013190A JP2001201496A JP2001201496A JP2003013190A JP 2003013190 A JP2003013190 A JP 2003013190A JP 2001201496 A JP2001201496 A JP 2001201496A JP 2001201496 A JP2001201496 A JP 2001201496A JP 2003013190 A JP2003013190 A JP 2003013190A
- Authority
- JP
- Japan
- Prior art keywords
- steel sheet
- amount
- oxidation
- less
- iron loss
- 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.)
- Granted
Links
Landscapes
- Soft Magnetic Materials (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、鉄リサイクルを可
能にする成分系を前提として、鉄損の優れた高級無方向
性電磁鋼板を提供することを目的とする。TECHNICAL FIELD The present invention has an object to provide a high-grade non-oriented electrical steel sheet excellent in iron loss on the premise of a component system that enables iron recycling.
【０００２】[0002]
【従来の技術】地球資源が枯渇するかも知れないとの近
未来的な状況の中で、いろいろな分野で資源の再利用の
動きが急である。このため、鉄鋼業でも各種の鉄スクラ
ップ−例えば、自動車、洗濯機、エアコンなど−を製鉄
原料として利用する必要が生じてきている。このために
は、従来、有害とされてきたＣｕ，Ｎｉ，Ｃｒ，Ｓｎな
どを積極的に利用する必要性が生じている。周知の如
く、無方向性電磁鋼板には１００年の歴史があるが、そ
こで払われてきた工業的な努力は、ＳｉとＡｌ以外の不
純物とされるＣ，Ｓ，Ｎ，Ｔｉ，Ｎｂなどを如何に低減
するかの歴史に尽きると言っても過言ではない。このた
め、鉄リサイクルで増加するＣｕ，Ｓｎ，Ｎｉ，Ｃｒな
ども、特に高級品には必要ないものとして長い間考えら
れてきた。2. Description of the Related Art In the near future, where resources of the earth may be exhausted, there is an urgent need to reuse resources in various fields. Therefore, in the steel industry, it has become necessary to use various types of iron scraps such as automobiles, washing machines, and air conditioners as iron-making raw materials. For this purpose, it is necessary to positively utilize Cu, Ni, Cr, Sn, etc., which have been conventionally regarded as harmful. As is well known, the non-oriented electrical steel sheet has a history of 100 years, but the industrial efforts that have been made there are to remove C, S, N, Ti, Nb, etc. which are impurities other than Si and Al. It is no exaggeration to say that it is all about the history of how to reduce it. For this reason, Cu, Sn, Ni, Cr, etc., which increase due to iron recycling, have long been considered to be unnecessary for high-grade products.
【０００３】一方で、同じ地球資源問題から、エネルギ
ーの無駄づかいをなくそうとの動きも強まっている。モ
ータの分野でも、例えば、一般家庭用のエアコンに見ら
れるように、消費電力低下による電気代が安いものが求
められている。このため、無方向性電磁鋼板には鉄損が
少ないものが求められている。特開平７−２６８５６８
号公報および特開平１１−２９３３３８号公報で、我々
は、これらＣｕ，Ｓｎ，Ｎｉ，Ｃｒの有効活用技術を提
案した。しかしながら、特に製品板厚の薄くて、且つ、
ＳｉとＡｌ量とが多い成分系で、高周波鉄損のバラツキ
が大きい問題があった。その原因は不明であった。な
お、特開平８−９７０２３号公報では、Ｓｂを添加する
ことで、酸化層を少なくして磁気特性を改善することが
開示されている。しかし、Ｓｂは高価な上、人体に有害
でもあること、また、酸化層を少なくした状態において
も磁気特性、特に高周波鉄損特性が改善されない場合が
あった。On the other hand, due to the same global resource problem, there is an increasing tendency to eliminate wasted energy. Also in the field of motors, there is a demand for a low electricity cost due to a reduction in power consumption, as seen in, for example, air conditioners for general households. Therefore, the non-oriented electrical steel sheet is required to have a small iron loss. JP-A-7-268568
In Japanese Patent Application Laid-Open No. 11-293338 and Japanese Patent Application Laid-Open No. 11-293338, we have proposed a technique for effectively utilizing these Cu, Sn, Ni, and Cr. However, especially the product thickness is thin, and
There is a problem that the variation of the high frequency iron loss is large in the component system containing a large amount of Si and Al. The cause was unknown. Japanese Patent Laid-Open No. 8-97023 discloses that Sb is added to improve the magnetic characteristics by reducing the oxide layer. However, Sb is expensive and harmful to the human body, and even when the oxide layer is reduced, the magnetic characteristics, particularly the high frequency iron loss characteristics, may not be improved.
【０００４】[0004]
【課題を解決するための課題】本発明は上記の点に鑑
み、地球環境問題からの鉄スクラップの積極活用と同時
に、課題であった、高級無方向性電磁鋼板の高周波鉄損
を改善する無方向性電磁鋼板を提供することを目的とす
る。In view of the above points, the present invention aims to positively utilize iron scrap from global environmental problems, and at the same time, to improve the high frequency iron loss of high-grade non-oriented electrical steel sheet, which is a problem. It is intended to provide a grain-oriented electrical steel sheet.
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するため
に本発明は（１）質量％で、
Ｃ ≦０．００４％、 Ｓｉ：１．６〜３．５％、
Ｍｎ≦１％、 Ｐ ≦０．０５％、
Ｓ ≦０．００２％、 Ａｌ：０．１〜３％、
Ｎ ≦０．００４％
を含有し、残部が実質的にＦｅ及び不可避的不純物から
なり、製品厚み０．１〜０．４mm、平均結晶粒径が４０
〜１７０μｍで、絶縁被膜を除去した表面状態での鋼板
表面の内部酸化量と外部酸化量が下式で表されることを
特徴とする高級無方向性電磁鋼板。
鋼板表面の内部酸化量×０．２０／板厚≦２００
２０≦鋼板表面の外部酸化量×０．２０／板厚≦５００
ただし、酸化量はＴ−Ｏで表す：ppm 、板厚：mm
（２）質量％で、
Ｃｕ：０．０５〜１％、 Ｎｉ：０．０１〜０．２％、
Ｃｒ：０．０１〜０．２％、 Ｓｎ：０．００３〜０．１％
をさらに含有することを特徴とする前項（１）に記載の
高級無方向性電磁鋼板。In order to achieve the above-mentioned object, the present invention is (1) mass%, C ≦ 0.004%, Si: 1.6 to 3.5%, Mn ≦ 1%, P ≦ 0.05%, S ≦ 0.002%, Al: 0.1 to 3%, N ≦ 0.004%, the balance consisting essentially of Fe and unavoidable impurities, product thickness 0.1 ~ 0.4mm, average crystal grain size is 40
A high-grade non-oriented electrical steel sheet characterized in that the internal oxidation amount and the external oxidation amount on the surface of the steel sheet in a surface state in which the insulating coating is removed are represented by the following formula: Internal oxidation amount on steel plate surface × 0.20 / plate thickness ≦ 200 20 ≦ external oxidation amount on steel plate surface × 0.20 / plate thickness ≦ 500 However, the oxidation amount is represented by TO: ppm, plate thickness: mm ( 2) By mass%, Cu: 0.05 to 1%, Ni: 0.01 to 0.2%, Cr: 0.01 to 0.2%, Sn: 0.003 to 0.1% are further contained. The high-grade non-oriented electrical steel sheet according to the above (1), which is characterized by:
【０００６】[0006]
【発明の実施の形態】以下、本発明を詳細に説明する。
本発明者らは、いわゆる熱延板焼鈍を有する無方向性電
磁鋼板の製造方法において、種々の研究を鋭意重ねた結
果、絶縁被膜を除去した表面状態での鋼板表面の内部酸
化量と外部酸化量を規定することによって、鉄損特性の
優れた高級無方向性電磁鋼板を製造することに成功し
た。BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
In the method for producing a non-oriented electrical steel sheet having so-called hot-rolled sheet annealing, the present inventors have earnestly conducted various studies, and as a result, the amount of internal oxidation and the external oxidation of the steel sheet surface in the surface state with the insulating coating removed. By defining the amount, we succeeded in producing a high-grade non-oriented electrical steel sheet with excellent iron loss characteristics.
【０００７】本発明者らは、高周波励磁における鉄損の
改善を考える場合、主磁束が鋼板表面近傍を流れること
から、鋼板表面をいかに制御するかが重要であると考え
た。特に本発明のＣｕ，Ｓｎ，Ｎｉ，Ｃｒ複合含有系で
は、鋼板表面の酸化が生じ易い。そこで焼鈍条件変更に
よる酸化を抑制することを志向したが、高周波鉄損が大
きく改善されない結果となり、詳細な調査をした。その
結果、焼鈍雰囲気中の窒素が鋼中に進入して、窒化によ
る鉄損劣化が生じていることが明らかになった。そこ
で、本発明者らは、鋼板の窒化を防ぐとともに、鉄損に
影響をおよぼしにくいような酸化の形態制御を検討し
た。その結果、適度な外部酸化層は、窒化を防止すると
ともに、地鉄界面の凹凸が内部酸化層と比べて、極めて
少ないため、主磁束が鋼板表面近傍を流れる高周波励磁
における鉄損の改善を図ることに成功した。The inventors of the present invention have considered that it is important to control the surface of the steel sheet because the main magnetic flux flows near the surface of the steel sheet when considering improvement of iron loss in high frequency excitation. In particular, in the Cu, Sn, Ni, Cr composite-containing system of the present invention, oxidation of the steel sheet surface is likely to occur. Therefore, we aimed to suppress the oxidation by changing the annealing conditions, but the high frequency iron loss was not greatly improved, and a detailed investigation was conducted. As a result, it was clarified that nitrogen in the annealing atmosphere penetrated into the steel to cause iron loss deterioration due to nitriding. Therefore, the present inventors have examined morphology control of oxidation that prevents nitriding of a steel sheet and is less likely to affect iron loss. As a result, a moderate outer oxide layer prevents nitriding and, as compared with the inner oxide layer, the unevenness of the base iron interface is extremely small, so the main magnetic flux improves iron loss in high-frequency excitation near the surface of the steel sheet. Was successful.
【０００８】[0008]
【発明の実施の形態】以下、本発明を詳細に説明する。
Ｃ量を０．００４％以下に規定したのは、これを超える
量では磁気時効が生じるからである。BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The amount of C is specified to be 0.004% or less because magnetic aging occurs when the amount exceeds C.
【０００９】Ｓｉ量を１．６〜３．５％に規定したが、
Ｓｉは鉄損を小さくするのに有効で、１．６％未満では
高周波鉄損が不満である。また，3.5%超では、冷間脆化
で打ち抜きの鋼板割れが生じるので、避ける。Although the amount of Si is specified to be 1.6 to 3.5%,
Si is effective in reducing iron loss, and high-frequency iron loss is unsatisfactory when it is less than 1.6%. Also, if it exceeds 3.5%, cold embrittlement may cause punching steel plate cracking, so avoid it.
【００１０】Ｍｎ量は、１％以下とする。Ｍｎは熱間割
れを防止する作用があるが、多すぎると添加コストの問
題もあるので、１％以下とする。The Mn content is 1% or less. Mn has an action of preventing hot cracking, but if it is too much, there is a problem of addition cost, so it is made 1% or less.
【００１１】Ｐ量は、０．０５％以下に制限する。Ｐも
結晶粒成長を阻害して、製品結晶粒径を細粒化するため
少ない方が好ましいが、この限界が０．０５％である。The P content is limited to 0.05% or less. P also inhibits the crystal grain growth and makes the product crystal grain size finer, so it is preferable that the amount is small, but this limit is 0.05%.
【００１２】Ｓ量は、０．００２％以下とする。Ｓは、
硫化物を形成して高周波鉄損を劣化させる。この限界
が、０．００２％である。The S content is 0.002% or less. S is
It forms sulfide and deteriorates high frequency iron loss. This limit is 0.002%.
【００１３】Ａｌ量は、０．１〜３％とする。Ａｌは鉄
損を小さくするが、０．１％未満では鉄損が不満で、ま
た、３％超では、冷間脆化で打ち抜きの鋼板割れが生じ
るので、避ける。The amount of Al is 0.1 to 3%. Al reduces iron loss, but if it is less than 0.1%, the iron loss is unsatisfactory, and if it exceeds 3%, it causes cold embrittlement to cause punched steel plate cracking, so avoid it.
【００１４】Ｎ量は、０．００４％以下とする。Ｎは、
窒化物を形成して鉄損を劣化させる。この限界が、０．
００４％である。The N content is 0.004% or less. N is
It forms a nitride and deteriorates iron loss. This limit is 0.
It is 004%.
【００１５】Ｃｕ量は、０．０５〜１％とする。鉄スク
ラップの有効活用の意味は、０．０５％以上のＣｕであ
り、また、１％を越えるとＣｕへげと称される熱延での
鋼板表面割れが発生するので避ける。特にこのＣｕへげ
は、Ｓｎが０．００３％以上含有される系で発生しやす
いので注意を要する。The amount of Cu is 0.05 to 1%. The meaning of effective utilization of iron scrap is 0.05% or more of Cu, and if it exceeds 1%, steel plate surface cracking in hot rolling called Cu dent occurs, so avoid it. In particular, this Cu barge is likely to occur in a system containing 0.003% or more of Sn, so caution is required.
【００１６】Ｎｉ量は、０．０１〜０．２％とする。鉄
スクラップの有効活用の意味は、０．０１％以上のＮｉ
であり、また、０．２％を越えると結晶粒成長が阻害さ
れるため不可とする。The amount of Ni is 0.01 to 0.2%. The meaning of effective utilization of iron scrap is 0.01% or more of Ni.
Further, if it exceeds 0.2%, the crystal grain growth is hindered, so that it is not possible.
【００１７】Ｃｒ量は、０．０１〜０．２％とする。鉄
スクラップの有効活用の意味は、０．０１％以上のＣｒ
であり、また、実用上、鉄スクラップから０．２％を越
えることはないので、０．０１〜０．２％とする。The Cr content is 0.01 to 0.2%. The meaning of effective utilization of iron scrap is 0.01% or more of Cr.
In addition, since it does not exceed 0.2% from iron scrap in practical use, it is set to 0.01 to 0.2%.
【００１８】Ｓｎ量は、０．００３〜０．１％とする。
鉄スクラップの有効活用の意味は、０．００３％以上の
Ｓｎであり、また、実用上、鉄スクラップから０．１％
を越えることはないので、０．０１〜０．１％とする。The Sn content is 0.003 to 0.1%.
The meaning of effective utilization of iron scrap is 0.003% or more of Sn, and practically 0.1% from iron scrap.
Since it does not exceed 0.1%, it is set to 0.01 to 0.1%.
【００１９】その他の元素として、集合組織を改善する
ための公知のＢ，Ｍｏなどを添加しても本発明として有
害なものではない。但し、添加コストの問題があるの
で、それぞれ０．１％以下が好ましい。また、公知の有
害元素、Ｔｉ，Ｎｂは０．０１％以下が好ましい。ま
た、本発明は高価なＳｂを添加しないので、製鋼作業の
不可避的不純物としてのＳｂ量は、０．０１％未満であ
る。The addition of known elements such as B and Mo for improving the texture as other elements is not harmful for the present invention. However, since there is a problem of addition cost, each content is preferably 0.1% or less. Further, the known harmful elements, Ti and Nb, are preferably 0.01% or less. Moreover, since the present invention does not add expensive Sb, the amount of Sb as an unavoidable impurity in the steelmaking operation is less than 0.01%.
【００２０】製鋼で上記の成分に調整された連続鋳造ス
ラブは、通常の熱間圧延を行われて熱延板とされる。The continuously cast slab adjusted to the above components by steelmaking is subjected to ordinary hot rolling to be a hot rolled sheet.
【００２１】熱延板は、次いで、焼鈍されても良いし焼
鈍されなくても良い。熱延板焼鈍を実施したほうが、磁
束密度が改善されるが本発明の目的は鉄損改善なので、
熱延板焼鈍を省略することも可能である。熱延板焼鈍
は、通常の８００〜１２００℃が好ましい。The hot rolled sheet may then be annealed or unannealed. When hot-rolled sheet annealing is performed, the magnetic flux density is improved, but the purpose of the present invention is to improve iron loss,
It is also possible to omit hot-rolled sheet annealing. The hot-rolled sheet annealing is preferably at 800 to 1200 ° C.
【００２２】次いで、冷延を行ってから、焼鈍を実施す
る。焼鈍後の鋼板の平均結晶粒径は、４０μｍ以上、１
７０μｍ以下とする。４０μｍ未満でも、１７０μｍ超
でも高周波鉄損が悪くなる。結晶粒径を制御するために
は、通常の温度×時間制御をすればよい。Next, after cold rolling, annealing is carried out. The average grain size of the steel sheet after annealing is 40 μm or more, 1
It is 70 μm or less. If it is less than 40 μm or more than 170 μm, the high frequency iron loss becomes worse. In order to control the crystal grain size, ordinary temperature × time control may be performed.
【００２３】本発明のポイントである鋼板表面の内部酸
化量は、下式の範囲に制御する必要がある。
鋼板表面の内部酸化量×０．２０／板厚≦２００
ただし、鋼板表面の内部酸化量はＴ−Ｏで表す：ppm 、
板厚：mm
鋼板表面の内部酸化量が上記範囲を越えると、鉄損の劣
化が大きいためである。ここでいう鋼板表面の内部酸化
量とは、図１（ａ）に示すような、地鉄合金内に拡散
し、固溶した酸素が、主として溶媒金属より酸化されや
すい溶質金属と反応した量のことで、Ｓｉ，Ａｌ，Ｍｎ
などがリッチの酸化層のことである。The amount of internal oxidation on the surface of the steel sheet, which is the point of the present invention, must be controlled within the range of the following formula. Internal oxidation amount on steel plate surface x 0.20 / plate thickness ≤ 200 However, the internal oxidation amount on the steel plate surface is represented by TO: ppm,
Plate thickness: mm When the amount of internal oxidation on the surface of the steel plate exceeds the above range, iron loss is greatly deteriorated. The amount of internal oxidation on the surface of the steel sheet here means the amount of oxygen diffused in the base iron alloy and dissolved as a solid solution, as shown in FIG. Therefore, Si, Al, Mn
Is a rich oxide layer.
【００２４】鋼板表面の内部酸化量に関係する酸化層
は、地鉄と境界面の凹凸が一般的に大きいので、基本的
に磁束の流れを阻害して、鉄損を著しく劣化させると考
えられる。したがって、その量は少なければ少ないほど
よいと考えられる。即ち、鋼板表面の内部酸化量×０．
２０／板厚≦２００を逸脱すると、ヒステリシス損失が
著しく増大して、鉄損を著しく劣化すると考えられる。
なお、内部酸化量の下限についてはゼロも含み、内部酸
化がゼロで外部酸化のみの状態でも本発明は含まれる。Since the oxide layer related to the internal oxidation amount on the surface of the steel sheet generally has large irregularities on the boundary surface with the base iron, it is considered that the flow of magnetic flux is basically obstructed and iron loss is significantly deteriorated. . Therefore, the smaller the amount, the better. That is, the amount of internal oxidation on the surface of the steel sheet x 0.
When 20 / plate thickness ≦ 200 is exceeded, it is considered that the hysteresis loss is significantly increased and the iron loss is significantly deteriorated.
In addition, the lower limit of the internal oxidation amount includes zero, and the present invention is also included in a state where the internal oxidation is zero and only the external oxidation is performed.
【００２５】さらに鋼板表面の外部酸化量は、下式の範
囲に制御する必要がある。
２０≦鋼板表面の外部酸化量×０．２０／板厚≦５００
ただし、鋼板表面の外部酸化量はＴ−Ｏで表す：ppm 、
板厚：mm
鋼板表面の外部酸化量が上記範囲を越えると、鉄損の劣
化が大きいためである。ここでいう鋼板表面の外部酸化
量とは、図１（ｂ）に示すような、地鉄合金内の溶質元
素の外方拡散によって生じる酸化層の量のことである。Further, it is necessary to control the amount of external oxidation on the surface of the steel plate within the range of the following formula. 20 ≦ external oxidation amount of steel plate surface × 0.20 / plate thickness ≦ 500 However, the external oxidation amount of the steel plate surface is represented by T−O: ppm,
This is because when the amount of external oxidation on the surface of the steel sheet exceeds the above range, the iron loss is greatly deteriorated. The amount of external oxidation on the surface of the steel sheet referred to here is the amount of an oxide layer generated by outward diffusion of solute elements in the base iron alloy as shown in FIG. 1 (b).
【００２６】鋼板表面の外部酸化量は上述したように、
ある適正範囲があるが、２０≦鋼板表面の外部酸化量×
０．２０／板厚を逸脱した場合は、鋼板に焼鈍雰囲気か
らの窒化が生じ、これが磁束の流れを阻害して、鉄損を
著しく劣化させていると考えられる。一方、鋼板表面の
外部酸化量×０．２０／板厚≦５００を逸脱した場合
は、鋼板断面に占める非磁性物としての割合が多くなる
ため、鉄損特性に影響を及ぼすと考えられる。The amount of external oxidation on the surface of the steel sheet is, as described above,
There is an appropriate range, but 20 ≤ the amount of external oxidation on the steel plate surface ×
When it deviates from 0.20 / thickness, it is considered that nitriding occurs in the steel sheet from the annealing atmosphere, which impedes the flow of magnetic flux and significantly deteriorates iron loss. On the other hand, when the amount of external oxidation on the surface of the steel sheet × 0.20 / thickness ≦ 500 is exceeded, the proportion of the non-magnetic material in the cross section of the steel sheet increases, which is considered to affect the iron loss characteristics.
【００２７】これらの鋼板表面の内部酸化量、外部酸化
量は、鋼板断面の研磨面をＳＥＭ−ＥＤＡＸで、５００
０倍以上の倍率で、まず、それぞれの酸化層として同定
して、その後、その部分を化学分析することによって得
ることができる。具体的には、製品板全体のＴ−Ｏ量を
分析して、その後ＳＥＭ−ＥＤＡＸで、鋼板表面の酸化
層が外部酸化層か内部酸化層かを観察する。ＳＥＭ−Ｅ
ＤＡＸの観察結果、内部酸化層と外部酸化層が共存して
いる場合は、酸洗で外部酸化層を除去した後のＴ−Ｏ量
を分析して、内部酸化量とし、前記製品板全体のＴ−Ｏ
量との差を外部酸化量とした。なお、鋼板表面の内部酸
化量、外部酸化量を制御する方法としては、例えば、Ｐ
Ｈ2 Ｏ／ＰＨ2 制御がある。The amount of internal oxidation and the amount of external oxidation on the surface of these steel sheets were determined by SEM-EDAX of the polished surface of the steel sheet cross section to be 500.
It can be obtained by first identifying each oxide layer at a magnification of 0 or more and then chemically analyzing the portion. Specifically, the TO amount of the entire product plate is analyzed, and then the SEM-EDAX is used to observe whether the oxide layer on the surface of the steel sheet is the outer oxide layer or the inner oxide layer. SEM-E
As a result of DAX observation, when the internal oxide layer and the external oxide layer coexist, the amount of TO after removing the external oxide layer by pickling is analyzed to obtain the internal oxidation amount, and T-O
The difference with the amount was defined as the amount of external oxidation. In addition, as a method of controlling the internal oxidation amount and the external oxidation amount of the steel plate surface, for example, P
There is H 2 O / PH 2 control.
【００２８】鋼板表面の内部酸化量、外部酸化量が、鉄
損特性に影響を及ぼす理由を、本発明者らは以下のよう
に考えている。The present inventors consider the reason why the amount of internal oxidation and the amount of external oxidation on the surface of the steel sheet affect the iron loss characteristics as follows.
【００２９】鋼板表面の内部酸化量に関係する酸化層
は、地鉄と境界面の凹凸が一般的に大きいので、基本的
に磁束の流れを阻害して、鉄損を著しく劣化させると考
えられる。したがって、その量は少なければ少ないほど
よいと考えられる。即ち、上述した範囲を逸脱すると、
ヒステリシス損失が著しく増大して、鉄損を著しく劣化
すると考えられる。Since the oxide layer related to the internal oxidation amount on the surface of the steel sheet generally has large irregularities on the boundary surface with the base iron, it is considered that the flow of magnetic flux is basically blocked and iron loss is significantly deteriorated. . Therefore, the smaller the amount, the better. That is, if it deviates from the above range,
It is considered that the hysteresis loss is significantly increased and the iron loss is significantly deteriorated.
【００３０】一方、鋼板表面の外部酸化量は上述したよ
うに、ある適正範囲があるが、適正酸化量未満の場合
は、鋼板に焼鈍雰囲気からの窒化が生じ、これが磁束の
流れを阻害して、鉄損を著しく劣化させていると考えら
れる。On the other hand, the amount of external oxidation on the surface of the steel sheet has a certain appropriate range as described above, but if it is less than the appropriate amount of oxidation, nitriding from the annealing atmosphere occurs in the steel sheet, which impedes the flow of magnetic flux. It is considered that iron loss is significantly deteriorated.
【００３１】しかし、適正量以上では、鋼板断面に占め
る非磁性物としての割合が多くなるため、鉄損特性に影
響を及ぼすと考えられる。However, if the amount is more than the proper amount, the proportion of the non-magnetic material in the cross section of the steel sheet increases, and it is considered that the iron loss characteristics are affected.
【００３２】再結晶焼鈍後は、通常の絶縁皮膜が塗布乾
燥されて出荷される。出荷された後は、打ち抜き、積層
固定され、そのまま、または焼鈍されて（特に固定子
が、磁性改善のために焼鈍される場合がある）モータコ
アや小型トランスコアとなる。以下、実施例で説明す
る。After the recrystallization annealing, a usual insulating film is applied and dried before shipment. After shipping, it is punched, laminated and fixed, as it is, or annealed (in particular, the stator may be annealed to improve magnetism) to form a motor core or a small transformer core. Hereinafter, description will be made with reference to examples.
【００３３】[0033]
【実施例】（実施例１）３０kg真空溶解を実施して、表
１に示す各種成分のインゴットを作成した。これを１０
５０℃に加熱してから、１０mm厚の鋼片に分塊した。次
いで、更に、１０５０℃に加熱してから、１．８mmの熱
延板を作成した。次いで、１１００℃で３０秒均熱の窒
素中焼鈍を行ってから大気中放冷した。酸洗後、冷延し
て０．３５mm厚とした。次いで、脱脂して、１０００℃
で３０秒の焼鈍を、ＰＨ2 ０／ＰＨ2 を０．０１〜０．
５０に変化させて実施した。１００mm角試料を切り出し
てから、圧延方向とそれと直角の方向の４００Ｈz 鉄損
を測定し、平均して表１に示した。また、鋼板断面の平
均結晶粒径を圧延方向の直線をよこぎる結晶粒径の粒界
個数をカウントして求めた。さらにＳＥＭ−ＥＤＡＸ
で、鋼板表面の酸化層が内部酸化層か外部酸化層である
かを同定して、化学分析によって、その量を調べた。定
量化は、次の通りに行った。まず、製品板全体のＴ−Ｏ
量(total酸素量) を分析して、その後ＳＥＭ−ＥＤＡＸ
で、鋼板表面の酸化層が外部酸化層か内部酸化層かを観
察する。ＳＥＭ−ＥＤＡＸの観察結果、内部酸化層と外
部酸化層が共存している場合は、酸洗で外部酸化層を除
去した後のＴ−Ｏ量を分析して、内部酸化量とし、前記
製品板全体のＴ−Ｏ量との差を外部酸化量とした。Example (Example 1) 30 kg of vacuum melting was carried out to prepare ingots of various components shown in Table 1. This is 10
After heating to 50 ° C., it was agglomerated into 10 mm thick steel pieces. Then, after further heating to 1050 ° C., a 1.8 mm hot rolled sheet was prepared. Next, after soaking in nitrogen at 1100 ° C. for 30 seconds soaking, it was left to cool in the air. After pickling, it was cold rolled to a thickness of 0.35 mm. Next, degreasing and 1000 ° C
Annealing for 30 seconds at pH 20 / PH 2 of 0.01 to 0.
The value was changed to 50. After cutting a 100 mm square sample, the 400 Hz iron loss in the rolling direction and the direction perpendicular to the rolling direction was measured and shown in Table 1 as an average. Further, the average crystal grain size of the steel sheet cross section was obtained by counting the number of grain boundaries of the crystal grain size crossing a straight line in the rolling direction. Furthermore SEM-EDAX
Then, it was identified whether the oxide layer on the surface of the steel sheet was an internal oxide layer or an external oxide layer, and the amount was investigated by chemical analysis. Quantification was performed as follows. First, the TO of the whole product plate
Amount (total oxygen amount) is analyzed and then SEM-EDAX
Then, it is observed whether the oxide layer on the surface of the steel sheet is the outer oxide layer or the inner oxide layer. As a result of SEM-EDAX observation, when the internal oxide layer and the external oxide layer coexist, the amount of TO after removing the external oxide layer by pickling is analyzed to obtain the internal oxidation amount, and the product plate is used. The amount of external oxidation was defined as the difference from the total amount of TO.
【００３４】[0034]
【表１】 [Table 1]
【００３５】表１に示すように、本発明の成分範囲を外
れるもの、内部および外部酸化量をはずれるものは、鉄
損特性が不良となった。なお、製品での成分分析も実施
したが、インゴットでの分析結果と同じであった。As shown in Table 1, the iron loss characteristics were poor for those that deviated from the component range of the present invention and those that deviated from the internal and external oxidation amounts. In addition, although the component analysis of the product was also performed, it was the same as the analysis result of the ingot.
【００３６】（実施例２）重量％で、０．００３５％
Ｃ、２．２％Ｓｉ、０．１８％Ｍｎ、０．０１％Ｐ、
０．００３５％Ｓ、２．１％Ａｌ、０．００１５％Ｎ、
０．００１％Ｎｂ、０．５％Ｃｕ、０．０８％Ｓｎ、
０．０８％Ｎｉ、０．１１％Ｃｒ、０．００１％Ｔｉ、
０．００２％Ｍｏ、０．００１％Ｖ、０．０００１％
Ｂ、０．０００２％Ｓｂを含むスラブを１０５０℃で加
熱してから、２．５mm厚の熱延コイルを製造した。次い
で、８５０℃×１０秒の窒素中焼鈍をして、酸洗した。
酸化層を調査したが、認められなかった。次いで、０．
２mmまで冷延し、脱脂後、均熱温度を表２のように変更
して１０秒均熱の焼鈍を、ＰＨ2 ０／ＰＨ2 を０．０１
〜０．５０に変化させて実施した。次いで、有機、無機
混合の絶縁皮膜を１μｍ厚で焼き付けした。次いで、エ
プスタイン試料に切断してから、磁気特性を測定した。
また、鋼板表面の内部酸化量、外部酸化量、結晶粒径を
実施例１に示した方法で測定して、表２に示した。(Example 2) 0.0035% by weight
C, 2.2% Si, 0.18% Mn, 0.01% P,
0.0035% S, 2.1% Al, 0.0015% N,
0.001% Nb, 0.5% Cu, 0.08% Sn,
0.08% Ni, 0.11% Cr, 0.001% Ti,
0.002% Mo, 0.001% V, 0.0001%
A slab containing B and 0.0002% Sb was heated at 1050 ° C., and then a hot rolled coil having a thickness of 2.5 mm was manufactured. Then, it was annealed in nitrogen at 850 ° C. for 10 seconds and pickled.
The oxide layer was examined, but not found. Then 0.
Cold rolled to 2 mm, degreased, the annealing changes to 10 ByoHitoshinetsu as shown in Table 2 the soaking temperature, the PH 2 0 / PH 2 0.01
It carried out by changing to 0.50. Next, an organic / inorganic mixed insulating film was baked to a thickness of 1 μm. Then, the magnetic properties were measured after cutting into Epstein samples.
Further, the amount of internal oxidation, the amount of external oxidation, and the crystal grain size of the surface of the steel sheet were measured by the method shown in Example 1 and shown in Table 2.
【００３７】[0037]
【表２】 [Table 2]
【００３８】表２に示すように、本発明範囲の結晶粒
径、鋼板表面の内部酸化量、外部酸化量で優れた磁気特
性が得られた。As shown in Table 2, excellent magnetic properties were obtained with the crystal grain size, the amount of internal oxidation on the surface of the steel sheet, and the amount of external oxidation within the range of the present invention.
【００３９】（実施例３）表３を示すように、ＳｉとＡ
ｌ量とを調整した連続鋳造スラブを供試材として用い
た。その他の成分としては、実験Ｎｏ．１〜９について
は、０．００２％Ｃ、０．２％Ｍｎ、０．０３％Ｐ、
０．０００２％Ｓ、０．０００９％Ｎ、０．２５％Ｃ
ｕ、０．０４％Ｓｎ、０．０５％Ｎｉ、０．０５％Ｃｒ
に固定した。また、実験Ｎｏ．１，０と１１のみ、０．
００１％Ｃ、０．２％Ｍｎ、０．０３％Ｐ、０．０００
２％Ｓ、０．０００９％Ｎで、Ｃｕ、Ｓｎ、Ｎｉ、Ｃｒ
についてはそれぞれ０．０００２％以下とした。このス
ラブを１１００℃で加熱してから、１．６mm厚の熱延コ
イルを製造した。次いで、９００℃で６０秒の焼鈍をＮ
2 中で実施した。酸洗してから、０．２５mmまで冷延し
た。この冷延板で表層酸化層を観察調査したが、酸化層
は存在しなかった。脱脂後、１１００℃×２０秒の均熱
焼鈍を、ＰＨ2 ０／ＰＨ2 を０．０１〜０．５０に変化
させて実施した。その後、絶縁皮膜（クロム酸、マグネ
シュウム、アクリル系の半有機皮膜）を約１．５μｍ厚
焼き付けた。また、エプスタイン試験片で磁気特性を測
定した。鋼板表面の内部酸化量、外部酸化量は実施例１
で示した方法で調べた。なお製品の平均結晶粒径は、い
づれも１５０〜１５５μｍであった。(Example 3) As shown in Table 3, Si and A
A continuously cast slab with the adjusted amount of 1 was used as a test material. As other components, Experiment No. For 1 to 9, 0.002% C, 0.2% Mn, 0.03% P,
0.0002% S, 0.0009% N, 0.25% C
u, 0.04% Sn, 0.05% Ni, 0.05% Cr
Fixed to. In addition, the experiment No. 1, 0 and 11 only, 0.
001% C, 0.2% Mn, 0.03% P, 0.000
2% S, 0.0009% N, Cu, Sn, Ni, Cr
For each of these, 0.0002% or less was set. The slab was heated at 1100 ° C. and then a 1.6 mm thick hot rolled coil was produced. Then, anneal at 900 ° C. for 60 seconds to N
Conducted in 2 . After pickling, it was cold rolled to 0.25 mm. Observation and examination of the surface oxide layer on this cold-rolled sheet revealed that no oxide layer was present. After degreasing, the soaking annealing of 1100 ° C. × 20 seconds, was performed by changing the PH 2 0 / PH 2 in the 0.01 to 0.50. After that, an insulating film (chromic acid, magnesium, acrylic semi-organic film) was baked to a thickness of about 1.5 μm. In addition, magnetic properties were measured with an Epstein test piece. The amount of internal oxidation and the amount of external oxidation on the surface of the steel sheet are those of Example
It investigated by the method shown by. The average crystal grain size of each product was 150 to 155 μm.
【００４０】[0040]
【表３】 [Table 3]
【００４１】表３に示すように、成分、鋼板表面の内部
酸化量、外部酸化量を本発明範囲に制御したものは、優
れた鉄損特性を示した。なお、最終の鋼板の成分をチェ
ックしたが、スラブ成分と同一であった。As shown in Table 3, those in which the components, the amount of internal oxidation on the surface of the steel sheet, and the amount of external oxidation were controlled within the range of the present invention showed excellent iron loss characteristics. The composition of the final steel sheet was checked and found to be the same as the slab composition.
【００４２】[0042]
【発明の効果】地球環境問題からの鉄スクラップを積極
活用し、同時に、高周波鉄損特性を改善した無方向性電
磁鋼板およびその製造方法を提供することができた。Industrial Applicability It has been possible to provide a non-oriented electrical steel sheet and a method for producing the same, which positively utilize iron scrap due to global environmental problems and, at the same time, improve high frequency iron loss characteristics.
【図１】酸化層の形態を模式的に示し、（ａ）は内部酸
化、（ｂ）は外部酸化を示す。FIG. 1 schematically shows the morphology of an oxide layer, where (a) shows internal oxidation and (b) shows external oxidation.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 廣神 定信 兵庫県姫路市広畑区富士町１番地 新日本 製鐵株式会社広畑製鐵所内 Ｆターム(参考） 5E041 AA02 CA02 CA04 HB15 NN01 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Hironobu Sadanobu 1 Fuji-machi, Hirohata-ku, Himeji-shi, Hyogo New Japan Hirohata Works, Ltd. F-term (reference) 5E041 AA02 CA02 CA04 HB15 NN01
Claims (2)
なり、製品厚み０．１〜０．４mm、平均結晶粒径が４０
〜１７０μｍで、絶縁被膜を除去した表面状態での鋼板
表面の内部酸化量と外部酸化量が下式で表されることを
特徴とする高級無方向性電磁鋼板。 鋼板表面の内部酸化量×０．２０／板厚≦２００ ２０≦鋼板表面の外部酸化量×０．２０／板厚≦５００ ただし、酸化量はＴ−Ｏで表す：ppm 、板厚：mm1. In mass%, C ≦ 0.004%, Si: 1.6 to 3.5%, Mn ≦ 1%, P ≦ 0.05%, S ≦ 0.002%, Al: 0. 1 to 3%, N ≤ 0.004%, the balance substantially consisting of Fe and unavoidable impurities, product thickness 0.1 to 0.4 mm, average crystal grain size 40
A high-grade non-oriented electrical steel sheet characterized in that the internal oxidation amount and the external oxidation amount on the surface of the steel sheet in a surface state in which the insulating coating is removed are represented by the following formula: Internal oxidation amount on steel plate surface x 0.20 / plate thickness ≤ 200 20 ≤ External oxidation amount on steel plate surface x 0.20 / plate thickness ≤ 500 However, the oxidation amount is represented by T-O: ppm, plate thickness: mm
級無方向性電磁鋼板。2. Cu: 0.05 to 1%, Ni: 0.01 to 0.2%, Cr: 0.01 to 0.2%, Sn: 0.003 to 0.1% in mass%. The high-grade non-oriented electrical steel sheet according to claim 1, further comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001201496A JP4276391B2 (en) | 2001-07-02 | 2001-07-02 | High grade non-oriented electrical steel sheet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001201496A JP4276391B2 (en) | 2001-07-02 | 2001-07-02 | High grade non-oriented electrical steel sheet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2003013190A true JP2003013190A (en) | 2003-01-15 |
| JP4276391B2 JP4276391B2 (en) | 2009-06-10 |
Family
ID=19038447
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001201496A Expired - Lifetime JP4276391B2 (en) | 2001-07-02 | 2001-07-02 | High grade non-oriented electrical steel sheet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4276391B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011157603A (en) * | 2010-02-02 | 2011-08-18 | Nippon Steel Corp | Non-oriented electromagnetic steel sheet and method for manufacturing non-oriented electromagnetic steel sheet |
| WO2013046661A1 (en) * | 2011-09-27 | 2013-04-04 | Ｊｆｅスチール株式会社 | Non-grain-oriented magnetic steel sheet |
| JP2017106059A (en) * | 2015-12-08 | 2017-06-15 | 新日鐵住金株式会社 | Nonoriented magnetic steel sheet and production method therefor |
| JP2017197806A (en) * | 2016-04-27 | 2017-11-02 | 新日鐵住金株式会社 | Nonoriented magnetic steel sheet for high-performance motor |
| JP2018154853A (en) * | 2017-03-15 | 2018-10-04 | 新日鐵住金株式会社 | Non-oriented electromagnetic steel sheet |
| WO2019132132A1 (en) * | 2017-12-26 | 2019-07-04 | 주식회사 포스코 | Non-oriented electrical steel sheet and method for preparing same |
-
2001
- 2001-07-02 JP JP2001201496A patent/JP4276391B2/en not_active Expired - Lifetime
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011157603A (en) * | 2010-02-02 | 2011-08-18 | Nippon Steel Corp | Non-oriented electromagnetic steel sheet and method for manufacturing non-oriented electromagnetic steel sheet |
| WO2013046661A1 (en) * | 2011-09-27 | 2013-04-04 | Ｊｆｅスチール株式会社 | Non-grain-oriented magnetic steel sheet |
| JPWO2013046661A1 (en) * | 2011-09-27 | 2015-03-26 | Ｊｆｅスチール株式会社 | Non-oriented electrical steel sheet |
| EP2762591A4 (en) * | 2011-09-27 | 2015-07-15 | Jfe Steel Corp | Non-oriented electrical steel |
| US9466411B2 (en) | 2011-09-27 | 2016-10-11 | Jfe Steel Corporation | Non-oriented electrical steel sheet |
| JP2017106059A (en) * | 2015-12-08 | 2017-06-15 | 新日鐵住金株式会社 | Nonoriented magnetic steel sheet and production method therefor |
| JP2017197806A (en) * | 2016-04-27 | 2017-11-02 | 新日鐵住金株式会社 | Nonoriented magnetic steel sheet for high-performance motor |
| JP2018154853A (en) * | 2017-03-15 | 2018-10-04 | 新日鐵住金株式会社 | Non-oriented electromagnetic steel sheet |
| WO2019132132A1 (en) * | 2017-12-26 | 2019-07-04 | 주식회사 포스코 | Non-oriented electrical steel sheet and method for preparing same |
| EP3733907A4 (en) * | 2017-12-26 | 2020-11-04 | Posco | Non-oriented electrical steel sheet and method for preparing same |
| JP2021509153A (en) * | 2017-12-26 | 2021-03-18 | ポスコＰｏｓｃｏ | Non-oriented electrical steel sheet and its manufacturing method |
| JP7142094B2 (en) | 2017-12-26 | 2022-09-26 | ポスコ | Non-oriented electrical steel sheet and manufacturing method thereof |
| US11492678B2 (en) | 2017-12-26 | 2022-11-08 | Posco | Non-oriented electrical steel sheet and method for preparing same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4276391B2 (en) | 2009-06-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3399061A1 (en) | Non-oriented electromagnetic steel sheet and method for producing non-oriented electromagnetic steel sheet | |
| JPWO2003002777A1 (en) | Non-oriented electrical steel sheet and manufacturing method thereof | |
| JP4855220B2 (en) | Non-oriented electrical steel sheet for split core | |
| JP2008127612A (en) | Non-oriented electromagnetic steel sheet for divided core | |
| JP4860783B2 (en) | Non-oriented electrical steel sheet | |
| JP6724712B2 (en) | Non-oriented electrical steel sheet | |
| JP4116749B2 (en) | Non-oriented electrical steel sheet | |
| JP2000129410A (en) | Nonoriented silicon steel sheet high in magnetic flux density | |
| JP2013044012A (en) | Non-oriented electromagnetic steel sheet, and method of producing the same | |
| JP2005120403A (en) | Non-oriented electrical steel sheet with low core loss in high-frequency region | |
| JP4276391B2 (en) | High grade non-oriented electrical steel sheet | |
| JP2639227B2 (en) | Manufacturing method of non-oriented electrical steel sheet | |
| JP2022509676A (en) | Non-oriented electrical steel sheet and its manufacturing method | |
| JP6123234B2 (en) | Electrical steel sheet | |
| JP4186384B2 (en) | Non-oriented electrical steel sheet | |
| JPH0849044A (en) | Monoriented silicon steel sheet for electric automobile and its production | |
| JP2003034820A (en) | Method for manufacturing grain-oriented electrical steel sheet superior in blanking property having no undercoat film | |
| JP2003293101A (en) | Nonoriented silicon steel sheet having excellent magnetic property and corrosion resistance after stress relieving annealing | |
| JP2005200755A (en) | Method for producing non-oriented silicon steel sheet | |
| JP4568999B2 (en) | Non-oriented electrical steel sheet and manufacturing method thereof | |
| JP2560579B2 (en) | Method for manufacturing high silicon steel sheet having high magnetic permeability | |
| JP3533655B2 (en) | Method for producing low-grade electrical steel sheet with small magnetic anisotropy and low-grade electrical steel sheet with small magnetic anisotropy | |
| JP2001164318A (en) | Method for producing nonoriented silicon steel sheet excellent in magnetic property and surface property | |
| JP7469694B2 (en) | Non-oriented electrical steel sheet and its manufacturing method | |
| JP2002115034A (en) | Nonoriented silicon steel sheet, stock for cold rolling therefor and its production method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050914 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080121 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080129 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080327 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080328 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090303 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090306 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 4276391 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120313 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130313 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130313 Year of fee payment: 4 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130313 Year of fee payment: 4 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130313 Year of fee payment: 4 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130313 Year of fee payment: 4 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140313 Year of fee payment: 5 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| EXPY | Cancellation because of completion of term |