JP2000288754A - Laser beam welding method excellent in low temp. toughness and electron beam welding method - Google Patents
Laser beam welding method excellent in low temp. toughness and electron beam welding methodInfo
- Publication number
- JP2000288754A JP2000288754A JP11100420A JP10042099A JP2000288754A JP 2000288754 A JP2000288754 A JP 2000288754A JP 11100420 A JP11100420 A JP 11100420A JP 10042099 A JP10042099 A JP 10042099A JP 2000288754 A JP2000288754 A JP 2000288754A
- Authority
- JP
- Japan
- Prior art keywords
- weight
- beam welding
- welding method
- laser beam
- electron beam
- 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
- Laser Beam Processing (AREA)
- Welding Or Cutting Using Electron Beams (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、高靭性溶接金属が
得られるレーザビーム溶接及び電子ビーム溶接に関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to laser beam welding and electron beam welding for obtaining a high toughness weld metal.
【０００２】[0002]
【従来の技術】溶接金属の低温靭性を改善する研究は古
くから行われ、靭性は金属組織に大きく依存することが
知られている。これらの知見によれば低温靭性が最も優
れている組織はアシキュラ−フェライトであることが多
くの研究報告例により示されている（例えば、溶接部の
組織と靭性堀井行彦第１２８回西山記念講座）。これら
の研究によれば、アシキュラ−フェライトの生成には、 適切な強度設計（約６００〜７００ＭＰａ程度）、
Ｔｉ酸化物の生成、という２つの条件が同時に満たされ
ることが必要である。2. Description of the Related Art Research for improving the low-temperature toughness of weld metal has been carried out for a long time, and it is known that toughness largely depends on a metal structure. According to these findings, many research reports show that the structure having the best low-temperature toughness is acicular-ferrite (for example, the structure of the welded part and the toughness of Yukihiko Horii 128th Nishiyama Memorial Lecture). . According to these studies, appropriate strength design (about 600-700MPa),
It is necessary that the two conditions of formation of Ti oxide be simultaneously satisfied.
【０００３】レーザビーム溶接あるいは電子ビーム溶接
においてこれらの条件を考えると、適切な強度設計は冷
却速度に応じて合金成分を調整することで対応できる。
しかしＴｉ酸化物の生成に必要な酸素の供給は一般に困
難であった。これまでの知見では、レーザビーム溶接を
行う際にフィラーワイヤを用いて溶接金属にＴｉ、Ｏの
添加を行うことで、溶接金属のミクロ組織をアシキュラ
ーフェライトとする方法がある（例えばＩＡＪｏｎｅ
ｓ：ＴＷＩＪ，Ｖｏｌ４，Ｎｏ．３，（１９９５），Ｐ
４２７−４８５）。しかしこの方法では、フィラ−ワイ
ヤの成分は鋼板表面からしか供給されないので、板厚が
厚くなると板厚方向での均一な成分分布が確保できない
という問題が生じる。従って、フィラ−ワイヤを用いる
このような方法は厚板のレーザビーム溶接や電子ビーム
溶接には適さない。[0003] Considering these conditions in laser beam welding or electron beam welding, an appropriate strength design can be coped with by adjusting the alloy components according to the cooling rate.
However, it was generally difficult to supply oxygen necessary for producing Ti oxide. According to the findings so far, there is a method in which the microstructure of the weld metal is made into an acicular ferrite by adding Ti and O to the weld metal using a filler wire when performing laser beam welding (for example, IAJone).
s: TWIJ, Vol4, No. 3, (1995), P
427-485). However, in this method, the component of the filler wire is supplied only from the surface of the steel sheet, so that when the thickness is large, there is a problem that a uniform component distribution in the thickness direction cannot be secured. Therefore, such a method using a filler wire is not suitable for laser beam welding or electron beam welding of a thick plate.
【０００４】別の方法としては特開平８−１４１７６３
号公報に開示されているように、Ｔｉを含有した鋼材を
レーザビーム溶接する際に、アシストガスに酸素や炭酸
ガスを含んだ混合ガスを用いてＴｉ酸化物を生成させ、
これによりアシキュラーフェライトを生成させることで
溶接金属を高靭性化する方法がある。しかしこの方法が
適用できるのはレーザ出力が１０ｋｗ程度までであり、
さらに高出力のレーザビーム溶接では著しく多量のプラ
ズマが発生し、溶け込み深さを劣化させるだけでなく、
溶接時に生成するキーホ−ルの安定性も損ない、ビード
形状が乱れるという問題を有している。また、この方法
は真空中で溶接を実施する電子ビーム溶接には適応する
ことは不可能である。Another method is disclosed in Japanese Patent Application Laid-Open No. H08-141773.
As disclosed in Japanese Patent Application Publication, when laser beam welding a steel material containing Ti, a titanium oxide is generated using a mixed gas containing oxygen or carbon dioxide gas as an assist gas,
Thus, there is a method of increasing the toughness of the weld metal by generating acicular ferrite. However, this method is applicable only when the laser output is about 10 kW,
In addition, high-power laser beam welding generates a remarkably large amount of plasma, which not only deteriorates the penetration depth,
There is a problem that the stability of the keyhole generated at the time of welding is impaired and the bead shape is disturbed. Further, this method cannot be applied to electron beam welding in which welding is performed in a vacuum.
【０００５】[0005]
【発明が解決しようとする課題】本発明は以上の背景を
鑑み、大出力のレーザビームや電子ビームで溶接する場
合において、安定して溶接金属のミクロ組織をアシキュ
ラーフェライトとし、高靭性な溶接金属を得ることので
きる溶接方法の提供を目的としている。SUMMARY OF THE INVENTION In view of the above background, the present invention stably uses a high-power laser beam or electron beam to stably form a microstructure of a weld metal into an acicular ferrite, thereby achieving high toughness welding. It aims at providing a welding method capable of obtaining metal.
【０００６】[0006]
【課題を解決するための手段】かかる課題を解決するた
めに、本発明者らは鋼材組成、溶接部に含まれるスケー
ル厚、溶接金属の組織及び靭性に関して研究を進めた結
果、これらの間に存在する諸関係を知見するに至り、本
発明を完成させたものであって、その要旨とするところ
は、下記（１）〜（４）のとおりである。Means for Solving the Problems In order to solve these problems, the present inventors have conducted research on the steel composition, the scale thickness contained in the welded portion, the structure and the toughness of the weld metal. The present inventors have completed the present invention by finding out the various existing relationships, and have the following points (1) to (4).
【０００７】（１）重量％で、Ｃ ：０．０１〜０．１
５％、Ｓｉ：０．０１〜１．５％、Ｍｎ：０．２〜２
％、Ｐ ：０．０３％以下、Ｓ ：０．０３％以下、Ａ
ｌ：０．０００５〜０．１％、Ｔｉ：０．００１〜０．
１％を含有し、残部がＦｅ及び不可避不純物からなり、
かつ、下記式１の値が０．０５〜０．２を満足する鋼材
を溶接する方法であって、溶接部分において相対する被
溶接面の少なくとも１つがスケール付着面であることを
特徴とするレーザビームもしくは電子ビーム溶接方法。 式１：０．０５＜（［％Ｃ］＋［％Ｓｉ］／３０＋［％
Ｍｎ］／２０＋［％Ｃｒ］／２０＋［％Ｎｉ］／６０＋
［％Ｍｏ］／１５＋［％Ｖ］／１０＋５［％Ｂ］＋［％
Ｃｕ］／２０）＜０．２ （２）鋼材が、重量％で、Ｃｒ：０．０１〜３％、Ｎ
ｉ：０．０１〜７％、Ｍｏ：０．００５〜２％、Ｃｕ：
０．０１〜３％、Ｎｂ：０．００１〜０．１％、Ｖ ：
０．００１〜１％、Ｂ ：０．０００１〜０．００２％
の１種または２種以上を、さらに含有することを特徴と
する前記（１）に記載のレーザビームもしくは電子ビー
ム溶接方法。(1) C: 0.01-0.1% by weight
5%, Si: 0.01 to 1.5%, Mn: 0.2 to 2
%, P: 0.03% or less, S: 0.03% or less, A
l: 0.0005 to 0.1%, Ti: 0.001 to 0.
1%, the balance being Fe and unavoidable impurities,
And a method of welding a steel material in which the value of the following formula 1 satisfies 0.05 to 0.2, wherein at least one of the opposed surfaces to be welded in the welded portion is a scale-adhered surface. Beam or electron beam welding method. Formula 1: 0.05 <([% C] + [% Si] / 30 + [%
Mn] / 20 + [% Cr] / 20 + [% Ni] / 60 +
[% Mo] / 15 + [% V] / 10 + 5 [% B] + [%
Cu] / 20) <0.2 (2) The steel material is, by weight%, Cr: 0.01 to 3%, N
i: 0.01 to 7%, Mo: 0.005 to 2%, Cu:
0.01 to 3%, Nb: 0.001 to 0.1%, V:
0.001-1%, B: 0.0001-0.002%
(1) The laser beam or electron beam welding method according to (1), further comprising one or more of the following.
【０００８】（３）鋼材が、重量％で、Ｍｇ：０．００
０１〜０．０２、Ｃａ：０．０００１〜０．０２、Ｚ
ｒ：０．００１〜０．１％、ＲＥＭ：０．００１〜０．
３％の１種または２種以上を、さらに含有することを特
徴とする前記（１）または（２）に記載のレーザビーム
もしくは電子ビーム溶接方法。(3) The steel material is Mg: 0.00% by weight.
01-0.02, Ca: 0.0001-0.02, Z
r: 0.001 to 0.1%, REM: 0.001 to 0.
The laser beam or electron beam welding method according to the above (1) or (2), further comprising 3% of one or more kinds.
【０００９】（４）溶接部分において相対する被溶接面
に付着しているスケール厚みが合計で、０．５〜８０μ
ｍであることを特徴とする前記（１）〜（３）のいずれ
かに記載のレーザビームもしくは電子ビーム溶接方法。(4) The total thickness of the scale adhering to the opposed surfaces to be welded in the welded portion is 0.5 to 80 μm.
m, the laser beam or electron beam welding method according to any one of the above (1) to (3).
【００１０】[0010]
【発明の実施の形態】まず、溶接される鋼材に関して、
添加元素のの規定理由を説明する。 Ｃ：０．０１重量％未満の極低Ｃ量では鋼板の強度が不
足し、また溶接金属においても凝固割れが発生する。逆
に、０．１５重量％超のＣでは溶接熱影響部及び溶接金
属の靭性が低下する。よって、Ｃは０．０１重量％以
上、０．１５重量％以下としたが、特に高靭性を確保す
る観点からはＣ量は低い方が好ましい。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, regarding the steel material to be welded,
The reason for defining the additional element will be described. C: At an extremely low C content of less than 0.01% by weight, the strength of the steel sheet is insufficient, and solidification cracking also occurs in the weld metal. Conversely, if C exceeds 0.15% by weight, the toughness of the weld heat affected zone and the weld metal decreases. Therefore, C is set to 0.01% by weight or more and 0.15% by weight or less, but from the viewpoint of securing high toughness, the lower the C amount, the more preferable.
【００１１】Ｓｉ：Ｓｉは脱酸剤及び強化元素として添
加されるが、０．０１重量％未満ではその効果が十分で
はなく、一方１．５％超では圧延時にスケ−ル起因の傷
を多発するようになる。よって、Ｓｉは０．０１重量％
以上、１．５重量％以下とした。 Ｍｎ：Ｍｎは鋼板の強度を向上する有用な元素であるが
０．２重量％未満ではその効果が無く、逆に２重量％超
の添加は逆にブロ−ホ−ルの発生を助長することを知見
し、Ｍｎは０．２重量％以上、２重量％以下とした。Si: Si is added as a deoxidizing agent and a strengthening element, but if its content is less than 0.01% by weight, its effect is not sufficient, while if it exceeds 1.5%, scratches due to scale occur frequently during rolling. I will be. Therefore, Si is 0.01% by weight.
As described above, the content was 1.5% by weight or less. Mn: Mn is a useful element for improving the strength of a steel sheet. However, if its content is less than 0.2% by weight, it has no effect. Conversely, the addition of more than 2% by weight promotes the generation of blowhole. And found that Mn was 0.2% by weight or more and 2% by weight or less.
【００１２】Ｐ及びＳ：Ｐ及びＳの過剰な添加は鋼板及
び熱影響部の靭性を劣化させるので、０．０３重量％以
下とした。 Ａｌ：Ａｌは脱酸剤として重要な元素であるが、０．０
００５重量％未満にすることは製鋼上の負荷が高く現実
的ではない。一方０．１％超では鋼板の衝撃靭性が劣化
する。よって、Ａｌの添加量は０．０００５重量％以上
０．１重量％以下とした。P and S: Since excessive addition of P and S deteriorates the toughness of the steel sheet and the heat-affected zone, the content is set to 0.03% by weight or less. Al: Al is an important element as a deoxidizing agent.
When the content is less than 005% by weight, the load on steelmaking is high and is not practical. On the other hand, if it exceeds 0.1%, the impact toughness of the steel sheet deteriorates. Therefore, the addition amount of Al is set to 0.0005% by weight or more and 0.1% by weight or less.
【００１３】Ｔｉ：Ｔｉはアシキュラーフェライトの変
態核として重要な元素である。但し０．００１重量％未
満ではその効果が十分ではなく、逆に０．１重量％超で
は鋼板の靭性が低下する。よって、Ｔｉの添加量は０．
００１重量％以上、０．１重量％以下とした。 Ｃｕ：Ｃｕは強度補償のためにＭｎの一部に代えて添加
することができる。但しその添加量は０．０１重量％未
満ではその効果が十分でなく、逆に３％超の場合には溶
接金属に凝固割れが発生する。従って、Ｃｕの添加量は
０．０１重量％以上、３重量％以下とした。Ti: Ti is an important element as a transformation nucleus of acicular ferrite. However, if the content is less than 0.001% by weight, the effect is not sufficient, and if it exceeds 0.1% by weight, the toughness of the steel sheet decreases. Therefore, the addition amount of Ti is 0.1.
It was set to 001% by weight or more and 0.1% by weight or less. Cu: Cu can be added instead of part of Mn for strength compensation. However, if the amount is less than 0.01% by weight, the effect is not sufficient, and if it exceeds 3%, solidification cracks occur in the weld metal. Therefore, the addition amount of Cu is set to 0.01% by weight or more and 3% by weight or less.
【００１４】Ｃｒ：Ｃｒは強度向上元素として添加する
ことができる。また、耐熱用鋼においては高温強度の確
保にも必要な元素であるが、０．０１重量％未満ではそ
の効果が十分ではなく、逆に３重量％超の添加は鋼板の
靭性を損ねる。従って、Ｃｒの添加量は０．０１重量％
以上、３重量％以下とした。 Ｎｉ：Ｎｉは鋼板の低温靭性を向上させる代表的な元素
であるが、０．０１重量％未満ではその効果が十分でな
く、逆に７重量％超では溶接金属に凝固割れを生じる。
よってＮｉの添加量は０．０１重量％以上、７重量％以
下とした。Cr: Cr can be added as a strength improving element. Further, in heat-resistant steel, it is an element necessary for ensuring high-temperature strength. However, if its content is less than 0.01% by weight, its effect is not sufficient, and if it exceeds 3% by weight, the toughness of the steel sheet is impaired. Therefore, the addition amount of Cr is 0.01% by weight.
At least 3% by weight. Ni: Ni is a typical element for improving the low-temperature toughness of the steel sheet. However, if its content is less than 0.01% by weight, its effect is not sufficient, and if it exceeds 7% by weight, solidification cracks occur in the weld metal.
Therefore, the addition amount of Ni is set to 0.01% by weight or more and 7% by weight or less.
【００１５】Ｍｏ：Ｍｏは溶接後熱処理（ＰＷＨＴ）脆
化を抑制する元素であり、Ｍｎの代替として添加できる
が、０．００５重量％未満ではその効果が十分ではな
く、逆に２重量％超では鋼板の靭性が低化する。よっ
て、Ｍｏの添加量は０．００５重量％以上、２重量％以
下とした。 Ｎｂ：ＮｂはＴＭＣＰプロセスにおいて、鋼板のミクロ
組織制御に重要な元素であるが、０．００１重量％未満
ではその効果が十分ではなく、逆に過剰な添加は鋼板の
靭性を損ねる。よって、Ｎｂの添加量は０．００１重量
％以上、０．１重量％以下とした。Mo: Mo is an element which suppresses post-weld heat treatment (PWHT) embrittlement and can be added as a substitute for Mn. However, if it is less than 0.005% by weight, its effect is not sufficient, and conversely, it exceeds 2% by weight. In this case, the toughness of the steel sheet decreases. Therefore, the amount of Mo added is set to 0.005% by weight or more and 2% by weight or less. Nb: Nb is an important element for controlling the microstructure of the steel sheet in the TMCP process, but if its content is less than 0.001% by weight, its effect is not sufficient, and conversely, excessive addition impairs the toughness of the steel sheet. Therefore, the addition amount of Nb is set to 0.001% by weight or more and 0.1% by weight or less.
【００１６】Ｖ：ＶもＴＭＣＰプロセスにおいて、鋼板
のミクロ組織制御に重要な元素であり、また耐熱鋼にお
いては高温強度の確保にも必要な元素であが、０．００
１重量％未満ではその効果が十分ではなく、逆に過剰な
添加は鋼板の靭性を損ねる。従って、Ｖの添加量は０．
００１重量％以上、１重量％以下とした。 Ｂ：Ｂも強度向上元素として添加することができるが、
０．０００１重量％未満ではその効果が十分ではなく、
逆に０．００２重量％超の添加は鋼板の靭性を低下させ
る。従って、Ｂの添加量は０．０００１重量％以上、
０．００２重量％以下とした。V: V is also an important element for controlling the microstructure of the steel sheet in the TMCP process, and is also an element necessary for ensuring high-temperature strength in heat-resistant steel.
If the content is less than 1% by weight, the effect is not sufficient. On the contrary, the excessive addition impairs the toughness of the steel sheet. Therefore, the added amount of V is 0.1.
It was set to 001% by weight or more and 1% by weight or less. B: B can also be added as a strength improving element,
If less than 0.0001% by weight, the effect is not enough,
Conversely, the addition of more than 0.002% by weight lowers the toughness of the steel sheet. Therefore, the addition amount of B is 0.0001% by weight or more,
It was made 0.002% by weight or less.
【００１７】Ｍｇ：Ｍｇは脱酸元素として作用するの
で、添加しても差し支えない。但し０．０００１重量％
未満ではその効果が十分ではなく、逆に０．０２重量％
超の添加はレーザビームもしくは電子ビーム溶接時にキ
ーホール内で発生するプラズマの安定性を損なう。よっ
て、Ｍｇの添加量は０．０００１重量％以上、０．０２
重量％以下とした。Mg: Mg acts as a deoxidizing element and may be added. However, 0.0001% by weight
If it is less than 0.02% by weight, the effect is not sufficient.
Excessive addition impairs the stability of the plasma generated in the keyhole during laser beam or electron beam welding. Therefore, the added amount of Mg is 0.0001% by weight or more and 0.02% by weight or more.
% By weight or less.
【００１８】Ｃａ：Ｃａも脱酸元素として作用するの
で、添加しても差し支えない。但し０．０００１重量％
未満ではその効果が十分ではなく、逆に０．０２重量％
超の添加はレーザビームもしくは電子ビーム溶接時にキ
ーホール内で発生するプラズマの安定性を損なう。よっ
て、Ｃａの添加量は０．０００１重量％以上、０．０２
重量％以下とした。Ca: Since Ca also acts as a deoxidizing element, it may be added. However, 0.0001% by weight
If it is less than 0.02% by weight, the effect is not sufficient.
Excessive addition impairs the stability of the plasma generated in the keyhole during laser beam or electron beam welding. Therefore, the addition amount of Ca is 0.0001% by weight or more and 0.02% by weight or more.
% By weight or less.
【００１９】Ｚｒ：Ｚｒも脱酸元素として作用するの
で、添加しても差し支えない。但し０．００１重量％未
満ではその効果が十分ではなく、逆に０．１重量％超で
は鋼板の靭性が低下する。よって、Ｚｒの添加量は０．
００１重量％以上、０．１重量％以下とした。 ＲＥＭ：ＲＥＭも脱酸元素として作用するので、添加し
ても差し支えない。但し０．００１重量％未満ではその
効果が十分ではなく、逆に０．３重量％超の添加はレー
ザビームもしくは電子ビーム溶接時にキーホール内で発
生するプラズマの安定性を損なう。よって、ＲＥＭの添
加量は０．００１重量％以上、０．３重量％以下とし
た。Zr: Since Zr also acts as a deoxidizing element, it may be added. However, if the content is less than 0.001% by weight, the effect is not sufficient, and if it exceeds 0.1% by weight, the toughness of the steel sheet decreases. Therefore, the addition amount of Zr is 0.1.
It was set to 001% by weight or more and 0.1% by weight or less. REM: Since REM also acts as a deoxidizing element, it may be added. However, if the content is less than 0.001% by weight, the effect is not sufficient, and if it exceeds 0.3% by weight, the stability of the plasma generated in the keyhole at the time of laser beam or electron beam welding is impaired. Therefore, the amount of REM added is set to 0.001% by weight or more and 0.3% by weight or less.
【００２０】次ぎに式１の規定理由の述べる。これは適
切な強度設計に関連するものである。つまり、レーザビ
ーム溶接や電子ビーム溶接の溶接金属で靭性が低下する
原因は、冷却速度が非常に大きいために焼き入れ効果に
よって溶接金属組織がマルテンサイトとになることであ
った。そこで式１の値を種々変化させ、レーザビーム溶
接を行い溶接金属の硬度を調査した。その結果を表１お
よび表２に示す。Next, the reason for defining Equation 1 will be described. This is related to proper strength design. That is, the cause of the decrease in toughness in the weld metal of laser beam welding or electron beam welding is that the weld metal structure becomes martensite due to the quenching effect due to the extremely high cooling rate. Therefore, the value of Equation 1 was changed variously, laser beam welding was performed, and the hardness of the weld metal was investigated. The results are shown in Tables 1 and 2.
【００２１】表１および表２から明らかなように、式１
の値が０．０５〜０．２である鋼材を溶接して作成され
た溶接金属のビッカ−ス硬度は１７０〜２３０であり、
アシキュラーフェライトの生成に適した硬度範囲といえ
る。一方、式１の値が本発明の規定範囲を逸脱する場合
はアシキュラーフェライトの生成には適さない硬度値で
ある。これらの結果より、アシキュラーフェライトの生
成には式１の値を特定することが有効であることが示唆
されている。As is clear from Tables 1 and 2, Equation 1
The Vickers hardness of a weld metal created by welding steel having a value of 0.05 to 0.2 is 170 to 230,
It can be said that the hardness range is suitable for producing acicular ferrite. On the other hand, when the value of the formula 1 is out of the range specified in the present invention, the hardness value is not suitable for producing acicular ferrite. From these results, it is suggested that it is effective to specify the value of Equation 1 for the generation of acicular ferrite.
【００２２】本発明におけるのスケールの作用について
説明する。本発明においてスケールは、鋼材に含有する
Ｔｉを有効に酸化させ、Ｔｉ酸化物の生成させる。すな
わち、Ｔｉ酸化物を生成するのに必要な酸素は、溶接部
における相対する被溶接面の少なくとも１つに付着して
いるスケールより供給される。ここで述べるスケールと
は鉄の酸化物一般であるが、具体的にはレーザ切断端面
スケール、プラズマ切断端面スケ−ル、ガス切断端面ス
ケール、鋼板ミルスケール等が、図１および図２に示す
ように溶接部において相対する被溶接面の少なくとも１
つに付着していることが必要である。酸素供給源とし
て、特に有効に作用するのはレーザ切断面とプラズマ切
断面のスケールである。The operation of the scale according to the present invention will be described. In the present invention, the scale effectively oxidizes Ti contained in the steel material to generate Ti oxide. That is, oxygen required to generate Ti oxide is supplied from a scale attached to at least one of the opposed surfaces to be welded in the welded portion. The scale described here is generally an oxide of iron, and specifically, a laser cut end scale, a plasma cut end scale, a gas cut end scale, a steel plate mill scale, and the like are shown in FIGS. 1 and 2. At least one of the opposed surfaces to be welded in the weld
It is necessary that they adhere to each other. Particularly effective as an oxygen source are the scale of the laser cut surface and the plasma cut surface.
【００２３】種々の鋼種におけるレーザ切断端面スケー
ル、プラズマ切断端面スケール、ガス切断端面スケ−
ル、鋼板ミルスケ−ル等をＸ線回折で分析した結果、ス
ケールは主にＦｅ2 Ｏ3 で構成されており、これらのス
ケ−ルからもたらされる酸素供給量に関してはスケール
厚さのみを議論すればよいことが確認された。そこで、
相対する被溶接面のスケール厚の合計値を種々変化さ
せ、溶接金属の酸素量を調査した結果を図３に示す。
０．５μｍ以上あれば酸素供給源として十分に機能する
ことが確認された。Ｘの値が０．５μm 未満の場合は供
給される酸素が不足してアシキュラーフェライトが十分
に生成しない。逆に８０μm 超の場合には過剰な酸素が
供給され靱性が損なわれるだけでなく、溶接時のキーホ
ール安定性も損なわれビード外観が劣化し、ブローホー
ル等の内質欠陥が発生する。よってスケールの合計厚は
０．５〜８０μm 以下とした。Laser cut end scale, plasma cut end scale, gas cut end scale for various steel types
As a result of X-ray diffraction analysis of steel scales and steel mill scales, the scale is mainly composed of Fe 2 O 3 , and only the thickness of the scale will be discussed with respect to the amount of oxygen supplied from these scales. It was confirmed that it was good. Therefore,
FIG. 3 shows the results of examining the oxygen content of the weld metal by variously changing the total value of the scale thickness of the opposed surfaces to be welded.
It has been confirmed that when it is 0.5 μm or more, it functions sufficiently as an oxygen supply source. When the value of X is less than 0.5 μm, the supplied oxygen is insufficient and the acicular ferrite is not sufficiently formed. On the other hand, if it exceeds 80 μm, excess oxygen is supplied and not only the toughness is impaired, but also the stability of the keyhole at the time of welding is impaired, the bead appearance is deteriorated, and internal defects such as blowholes are generated. Therefore, the total thickness of the scale is set to 0.5 to 80 μm or less.
【００２４】[0024]
【実施例】以下、実施例に基づいて本発明の効果を説明
する。実験に用いた鋼板は転炉で溶製し連続鋳造で２５
０ｍｍ厚のスラブとした。これを熱間圧延した後に機械
加工でミルスケールを研削して厚さ６ｍｍ、９ｍｍ、１
５ｍｍ、２０ｍｍの鋼板を準備した。鋼板の成分を表３
に示す。この鋼板をレーザ切断、プラズマ切断、ガス切
断して、切断端面にスケールが付着した供試鋼板を作成
した。切断端面のスケール厚は切断方法及び切断条件を
変化させて調整した。以上の鋼板を図３に示すＩ型突合
わせ形状でレーザビーム溶接及び電子ビ−ム溶接を実施
した。レーザビーム溶接の溶接条件を表４に、電子ビー
ム溶接の溶接条件を表５に示す。溶接後の鋼板には表６
の試験を実施し、その結果を表７、表８、表９、表１０
に示す。表７、表８、表９、表１０の中で、シャルピー
試験の吸収エネルギは各鋼板における最低値を記してあ
る。以上の結果より、本発明の溶接方法で作成された溶
接金属は全ての検査において合格したが、比較例として
検討した鋼板は不合格であった。EXAMPLES The effects of the present invention will be described below based on examples. The steel plate used for the experiment was melted in a converter and cast continuously for 25 minutes.
The slab was 0 mm thick. After hot-rolling, the mill scale is ground by machining to obtain a thickness of 6 mm, 9 mm,
Steel plates of 5 mm and 20 mm were prepared. Table 3 shows the composition of the steel sheet.
Shown in This steel sheet was subjected to laser cutting, plasma cutting, and gas cutting to prepare a test steel sheet having a scale attached to the cut end surface. The scale thickness of the cut end face was adjusted by changing the cutting method and cutting conditions. The above steel sheets were subjected to laser beam welding and electron beam welding in an I-shaped butt shape shown in FIG. Table 4 shows the welding conditions for laser beam welding, and Table 5 shows the welding conditions for electron beam welding. Table 6 shows the steel sheet after welding.
Table 7, Table 8, Table 9, Table 10
Shown in In Table 7, Table 8, Table 9, and Table 10, the absorbed energy of the Charpy test indicates the lowest value in each steel sheet. From the above results, the weld metal prepared by the welding method of the present invention passed all the inspections, but the steel sheet examined as a comparative example failed.
【００２５】[0025]
【表１】 [Table 1]
【００２６】[0026]
【表２】 [Table 2]
【００２７】[0027]
【表３】 [Table 3]
【００２８】[0028]
【表４】 [Table 4]
【００２９】[0029]
【表５】 [Table 5]
【００３０】[0030]
【表６】 [Table 6]
【００３１】[0031]
【表７】 [Table 7]
【００３２】[0032]
【表８】 [Table 8]
【００３３】[0033]
【表９】 [Table 9]
【００３４】[0034]
【表１０】 [Table 10]
【００３５】[0035]
【発明の効果】以上に示したように、本発明の方法を用
いれば、レーザビーム溶接および電子ビーム溶接におい
て健全な溶接部と高靭性な溶接金属が確保されるので、
その効果は多大であるといえる。As described above, by using the method of the present invention, a sound weld portion and a high toughness weld metal can be secured in laser beam welding and electron beam welding.
The effect can be said to be great.
【図１】図１は、本発明の溶接継手の一例（ギャップな
し）を示す断面模式図である。FIG. 1 is a schematic sectional view showing an example (without a gap) of a welded joint according to the present invention.
【図２】図２は、本発明の溶接継手の一例（ギャップな
し）を示す断面模式図である。FIG. 2 is a schematic cross-sectional view showing one example (without a gap) of the welded joint of the present invention.
【図３】図３は、スケール厚みと溶接金属の酸素量との
関係を示すグラフである。FIG. 3 is a graph showing a relationship between a scale thickness and an oxygen content of a weld metal.
１…レーザビームもしくは電子ビーム ２…鋼板 1: laser beam or electron beam 2: steel plate
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｂ２３Ｋ 103:04 (72)発明者 藤 雅雄 千葉県富津市新富20−１ 新日本製鐵株式 会社技術開発本部内 (72)発明者 粟飯原 周二 千葉県富津市新富20−１ 新日本製鐵株式 会社技術開発本部内 (72)発明者 星野 学 愛知県東海市東海町５−３ 新日本製鐵株 式会社名古屋製鐵所内 (72)発明者 斎藤 直樹 愛知県東海市東海町５−３ 新日本製鐵株 式会社名古屋製鐵所内 (72)発明者 都築 岳史 愛知県東海市東海町５−３ 新日本製鐵株 式会社名古屋製鐵所内 Ｆターム(参考） 4E066 AB09 CA03 CA08 4E068 BA00 BE00 CA17 DB01 ──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) B23K 103: 04 (72) Inventor Masao Fuji 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Within the headquarters (72) Inventor Shuji Awaihara 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Inside the Technology Development Headquarters (72) Inventor Manabu Hoshino 5-3 Tokai-cho, Tokai-shi, Aichi Prefecture Nippon Steel Corporation Nagoya Works (72) Inventor Naoki Saito 5-3 Tokai-cho, Tokai City, Aichi Prefecture Nippon Steel Corporation Nagoya Works (72) Inventor Takeshi Tsuzuki 5-3 Tokai-cho, Tokai City, Aichi Prefecture Made in New Japan F-term in Nagoya Works (Reference) 4E066 AB09 CA03 CA08 4E068 BA00 BE00 CA17 DB01
Claims (4)
び不可避不純物からなり、かつ、下記式１の値が０．０
５〜０．２を満足する鋼材を溶接する方法であって、溶
接部分において相対する被溶接面の少なくとも１つがス
ケール付着面であることを特徴とするレーザビームもし
くは電子ビーム溶接方法。 式１：［％Ｃ］＋［％Ｓｉ］／３０＋［％Ｍｎ］／２０
＋［％Ｃｒ］／２０＋［％Ｎｉ］／６０＋［％Ｍｏ］／
１５＋［％Ｖ］／１０＋５［％Ｂ］＋［％Ｃｕ］／２０C: 0.01 to 0.15%, Si: 0.01 to 1.5%, Mn: 0.2 to 2%, P: 0.03% or less, S: 0.03% or less, Al: 0.0005 to 0.1%, Ti: 0.001% to 0.1%, the balance being Fe and unavoidable impurities, and the value of the following formula 1 is 0 .0
A laser beam or electron beam welding method for welding steel materials satisfying 5-0.2, wherein at least one of opposed surfaces to be welded in a welded portion is a scale-adhered surface. Formula 1: [% C] + [% Si] / 30 + [% Mn] / 20
+ [% Cr] / 20 + [% Ni] / 60 + [% Mo] /
15 + [% V] / 10 + 5 [% B] + [% Cu] / 20
上を、さらに含有することを特徴とする請求項１に記載
のレーザビームもしくは電子ビーム溶接方法。2. The steel material is expressed by weight: Cr: 0.01 to 3%, Ni: 0.01 to 7%, Mo: 0.005 to 2%, Cu: 0.01 to 3%, Nb: The composition according to claim 1, further comprising one or more of 0.001 to 0.1%, V: 0.001 to 1%, and B: 0.0001 to 0.002%. Laser or electron beam welding method.
を、さらに含有することを特徴とする請求項１または２
に記載のレーザビームもしくは電子ビーム溶接方法。3. The steel material is, by weight%, Mg: 0.0001 to 0.02%, Ca: 0.0001 to 0.02%, Zr: 0.001 to 0.1%, REM: 0.001. 3. The composition according to claim 1, further comprising at least one kind of at least 0.3%.
The laser beam or electron beam welding method described in 1.
着しているスケール厚みが合計で、０．５〜８０μｍで
あることを特徴とする請求項１〜３のいずれかに記載の
レーザビームもしくは電子ビーム溶接方法。4. The laser beam or the laser beam according to claim 1, wherein a total thickness of scales attached to opposed surfaces to be welded in a welded portion is 0.5 to 80 μm. Electron beam welding method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10042099A JP4505076B2 (en) | 1999-04-07 | 1999-04-07 | Electron beam welding method for obtaining weld metal with excellent low temperature toughness |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10042099A JP4505076B2 (en) | 1999-04-07 | 1999-04-07 | Electron beam welding method for obtaining weld metal with excellent low temperature toughness |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000288754A true JP2000288754A (en) | 2000-10-17 |
| JP4505076B2 JP4505076B2 (en) | 2010-07-14 |
Family
ID=14273495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10042099A Expired - Fee Related JP4505076B2 (en) | 1999-04-07 | 1999-04-07 | Electron beam welding method for obtaining weld metal with excellent low temperature toughness |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4505076B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2889471A1 (en) * | 2005-08-02 | 2007-02-09 | Peugeot Citroen Automobiles Sa | Assembly of a steel component and an iron component by laser beam welding using an iron-nickel alloy insert, notably for components for motor vehicles |
| JP2008087034A (en) * | 2006-10-02 | 2008-04-17 | Nippon Steel Corp | Electron beam welded joint having excellent resistance to generation of brittle fracture |
| JP7485936B2 (en) | 2020-07-08 | 2024-05-17 | 日本製鉄株式会社 | Manufacturing method for welded joints using low-temperature Ni steel |
-
1999
- 1999-04-07 JP JP10042099A patent/JP4505076B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2889471A1 (en) * | 2005-08-02 | 2007-02-09 | Peugeot Citroen Automobiles Sa | Assembly of a steel component and an iron component by laser beam welding using an iron-nickel alloy insert, notably for components for motor vehicles |
| JP2008087034A (en) * | 2006-10-02 | 2008-04-17 | Nippon Steel Corp | Electron beam welded joint having excellent resistance to generation of brittle fracture |
| JP7485936B2 (en) | 2020-07-08 | 2024-05-17 | 日本製鉄株式会社 | Manufacturing method for welded joints using low-temperature Ni steel |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4505076B2 (en) | 2010-07-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI478785B (en) | High heat input welding steel | |
| JP6226542B2 (en) | Steel with excellent toughness in weld heat affected zone | |
| EP2422913B1 (en) | Electron beam welded joint excellent in brittle fracture resistance | |
| Guo et al. | Laser welding of high strength steels (S960 and S700) with medium thickness | |
| KR20190042052A (en) | METHOD FOR MANUFACTURING WELDING STRUCTURE OF FERRITE STEEL HEAVY DUTY STRIP | |
| WO2018047881A1 (en) | Flux cored wire for gas shield arc welding and welding metal | |
| EP2594657B1 (en) | Electron beam welded joint, steel material for use in electron beam welded joint, and manufacturing method thereof | |
| JP6448844B1 (en) | Welding method | |
| EP4265367A1 (en) | Welded member having excellent fatigue strength of welded portion and method for manufacturing same | |
| JP2000288754A (en) | Laser beam welding method excellent in low temp. toughness and electron beam welding method | |
| JP3939563B2 (en) | Cored wire and solid wire for laser welding of steel | |
| JP2005125348A (en) | Large heat input butt welded joint superior in brittle fracture characteristic resistance | |
| JP2018039024A (en) | Flux-cored wire for gas shield arc welding, and weld metal | |
| JP4492028B2 (en) | Laser beam welded joint and method for manufacturing laser beam welded joint | |
| JP4374104B2 (en) | Joints and structures made of ultra-fine steel with excellent brittle crack propagation stopping characteristics | |
| JPH10193173A (en) | Welding filler wire for damping alloy, and welding method | |
| JP4213830B2 (en) | Laser welding steel | |
| JP3351139B2 (en) | Welding method for low alloy high strength steel | |
| JP2004011008A (en) | Steel member and structure excellent in weld zone toughness | |
| JP6515287B2 (en) | Method of manufacturing welded joint | |
| JP2008087031A (en) | Welded joint having excellent resistance to generation of brittle fracture | |
| TWI846149B (en) | Manufacturing method of laser-arc hybrid welding joint | |
| JP2007262518A (en) | Fatigue crack resistant steel sheet for welding having excellent joint fatigue strength | |
| WO2000075388A1 (en) | High-tension steel material with excellent suitability for welding with high-energy-density heat source and welded structure thereof | |
| JP2001279324A (en) | Method for producing steel for laser welding |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050913 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080215 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080219 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080418 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20080722 |
|
| 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: 20100426 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130430 Year of fee payment: 3 |
|
| 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: 20130430 Year of fee payment: 3 |
|
| 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: 20140430 Year of fee payment: 4 |
|
| LAPS | Cancellation because of no payment of annual fees |