JP2011255403A - Method for joining aluminum plate material - Google Patents
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本発明は、板厚０．５〜３．０ｍｍのアルミニウム板材を複数枚溶接し、表面の平滑性に優れ、かつ、欠陥のない接合板を安価に提供する接合方法に関する。 The present invention relates to a joining method in which a plurality of aluminum plate members having a thickness of 0.5 to 3.0 mm are welded to provide a joining plate having excellent surface smoothness and no defects at low cost.
近年、種々の装置の大型化やコスト、歩留まり等の観点より、アルミニウム板材も従来に比べより大型化が要望されつつある。板厚０．５〜３．０ｍｍ程度の１枚板となると、従来の熱間圧延加工で対応可能ではある。しかしながら、平滑度を重要視した厚さに仕上げる冷間圧延では、現状の生産設備で対応できる幅以上のサイズのものには対応できない。 In recent years, from the viewpoints of increasing the size of various devices, cost, yield, and the like, aluminum plate materials have been demanded to be larger than before. When the sheet thickness is about 0.5 to 3.0 mm, it can be handled by conventional hot rolling. However, cold rolling that finishes to a thickness that places importance on smoothness cannot cope with a size larger than the width that can be handled by current production equipment.
そこで、従来の製造方法によって製造されたアルミニウム平板を接合することで必要とする大きさに対応することが考えられる。近年、アルミニウム平板を接合する方法で熱歪みや変形が少ないといわれている接合方法の一つに、固相接合である摩擦撹拌接合法（Ｆｒｉｃｔｉｏｎ Ｓｔｉｒ Ｗｅｌｄｉｎｇ、以下「ＦＳＷ」と記す）が挙げられる（例えば、特許文献１参照）。しかしながら、０．５〜３．０ｍｍの板材の接合となると、接合の際における熱の影響や内部応力等に起因して接合部付近にどうしても反り上がりや変形が生じ易い問題があった。 Therefore, it is conceivable to cope with the required size by joining the aluminum flat plates manufactured by the conventional manufacturing method. In recent years, one of the joining methods that are said to have little thermal distortion and deformation in the method of joining aluminum flat plates is a friction stir welding method (Friction Stir Welding, hereinafter referred to as “FSW”) that is solid phase joining. (For example, refer to Patent Document 1). However, when joining plate materials of 0.5 to 3.0 mm, there is a problem that warpage or deformation tends to occur in the vicinity of the joint due to the influence of heat or internal stress during the joining.
一般的な溶融接合方法として広く用いられているものとして、ティグ溶接やミグ溶接に代表されるアーク溶接が挙げられる。また、同じく溶融接合方法として、電子ビーム溶接とＣＯ２やＹＡＧ等に代表されるレーザ溶接も挙げられる。特許文献２には、直流正極性ティグ溶接を用いた工法が記載されている。溶接の対象部材としては、押出プレス機では製造不可能な広幅の大型ヒートシンク（押出形材）が用いられており、本発明によって製造される大型の平滑板にそのまま適用することはできないという問題があった。
Arc welding represented by TIG welding and MIG welding is widely used as a general melt bonding method. Similarly, examples of the fusion bonding method include electron beam welding and laser welding represented by CO 2 , YAG, and the like.
特許文献３に記載される押出形材の接合も、本発明によって製造される大型の平滑板にそのまま適用することはできないという問題があった。特許文献４に記載される溶接対象部材は０．０３ｍｍ以下の薄板材であり、本発明で用いる０．５〜３．０ｍｍのアルミニウム板材とは厚さにおいて著しく相違するので、本発明によって製造される大型の平滑板にそのまま適用することはできないという問題があった。
The joining of the extruded profile described in
本発明は上記従来技術の問題点を解決するためになされたものであり、厚さ０．５〜３．０ｍｍを有する複数枚のアルミニウム板材を、直流正極性ティグ溶接法にて溶接することにより、表面の平滑性に優れ、かつ、欠陥のない大型接合板を安価に製造する方法の提を目的とする。 The present invention has been made in order to solve the above-mentioned problems of the prior art, and by welding a plurality of aluminum plates having a thickness of 0.5 to 3.0 mm by a DC positive polarity TIG welding method. An object of the present invention is to provide a method for producing a large-sized bonded plate having excellent surface smoothness and no defects at low cost.
本発明は請求項１において、Ｍｇ：１．５ｍａｓｓ％以下を含有し残部Ａｌ及び不可避的不純物からなるＡｌ合金で構成され、厚さ０．５〜３．０ｍｍを有するアルミニウム板材を、被溶接材として複数枚用意し、隣接するアルミニウム板材の端面同士を突合せてこの突合せ部を直流正極性ティグ溶接法によって溶接することにより平滑板を製造する方法において、タングステン電極と被溶接材であるアルミニウム板材との距離を１．０ｍｍ以下とし、純度７５〜１００％で流量５〜１５リットル／分のＨｅをシールドガスとして用い、溶加材を用いず、溶接時における単位板厚当たりの入熱量を２５００〜１００００（Ｊ／ｃｍ２）とすることを特徴とするアルミニウム板材の接合方法とした。
The present invention is the invention as defined in
本発明は請求項２では請求項１において、前記アルミニウム合金が、Ｓｉ：２．０ｍａｓｓ％以下、Ｆｅ：１．０％ｍａｓｓ以下、Ｃｕ：０．５％ｍａｓｓ以下及びＭｎ：２．０％ｍａｓｓ以下の１種又は２種以上を更に含有するものとした。 According to a second aspect of the present invention, in the first aspect, the aluminum alloy includes Si: 2.0 mass% or less, Fe: 1.0% mass or less, Cu: 0.5% mass or less and Mn: 2.0% mass. The following 1 type or 2 types or more were further contained.
更に本発明は請求項３では請求項１又は２において、前記アルミニウム合金が、Ｃｒ：０．２ｍａｓｓ％以下、Ｚｎ：０．３ｍａｓｓ％以下及びＴｉ：０．２ｍａｓｓ％以下の１種又は２種以上を更に含有するものとした。
Further, in the present invention, the present invention provides the invention according to
本発明に係る溶接方法によって、厚さ０．５〜３．０ｍｍのアルミニウム板材を複数枚接合した、表面の平滑性に優れ、かつ、欠陥のない大型平滑板を安価に製造することができる。 By the welding method according to the present invention, a large smooth plate having excellent surface smoothness and having no defects can be produced at low cost by joining a plurality of aluminum plate members having a thickness of 0.5 to 3.0 mm.
Ａ．直流正極性ティグ溶接の選定
本発明では、溶接方法として直流正極性ティグ溶接を選定している。以下に、選定理由について述べる。
消耗電極（溶加材）を用いるミグ溶接方法では、溶接後において溶接ビードが存在するので、平滑な板材を得るには切削等の機械加工が必要となる。また、ＦＳＷは局部的な荷重を付加することにより板材に内部応力が残留し、接合後において反りや歪みが発生する。大型の接合装置となると、周辺機器類も大掛かりなものとなり、コスト増加が避けられない。ＣＯ２やＹＡＧを用いたレーザ溶接は、近年ではファイバー、ディスク、半導体等の製造に適用されており、いずれのレーザ溶接もアーク溶接に比べて熱歪みの発生が少ないといわれている。レーザ溶接は、非接触工法であって溶接速度も速く自動車の製造ラインにも使用されており、本発明のような薄板製品への適用は十分可能である。しかしながら、溶接機器類や周辺機器類を含めて装置が高額となり、安価な製造には適さない。電子ビーム溶接は厚板の深い溶け込みを特徴とする接合方法であるが、真空中のチャンバー内に被接合材を収容して溶接することが必須であり、本発明で用いるような大型の薄板への適用には不向きである。
A. Selection of DC positive polarity TIG welding In the present invention, DC positive polarity TIG welding is selected as a welding method. The reasons for selection are described below.
In the MIG welding method using a consumable electrode (filler material), since a weld bead exists after welding, machining such as cutting is required to obtain a smooth plate material. In addition, when FSW is applied with a local load, internal stress remains in the plate material, and warping and distortion occur after joining. If it becomes a large-sized joining device, peripheral equipment will also become large, and an increase in cost cannot be avoided. In recent years, laser welding using CO 2 or YAG has been applied to the production of fibers, disks, semiconductors, etc., and it is said that any laser welding generates less thermal distortion than arc welding. Laser welding is a non-contact method, has a high welding speed, and is used in a production line for automobiles, and can be sufficiently applied to a thin plate product as in the present invention. However, the apparatus including the welding equipment and peripheral equipment is expensive, and is not suitable for inexpensive manufacturing. Electron beam welding is a joining method characterized by deep penetration of a thick plate, but it is essential to accommodate the material to be joined in a vacuum chamber and weld it to a large thin plate as used in the present invention. It is not suitable for application of.
ティグ溶接は一般的に溶加材を加える工法であるが、溶加材を用いないでアークのみを照射することで被溶接材を溶融し接合することが可能である。本発明では、上記各溶接方法が有する欠点がない、溶加材を用いないティグ溶接を採用する。アルミニウム板材のティグ溶接では、電極を損傷させず、かつ、アルミニウム材材表面の酸化皮膜を除去するために、交流のティグ溶接が一般的に用いられる。しかしながら、交流ティグ溶接では、その原理上、電流の極性がマイナスとプラスに交互に反転する必要があるため接合速度を速く出来ないという欠点があった。 TIG welding is generally a method of adding a filler material, but it is possible to melt and join the workpieces by irradiating only the arc without using the filler material. In this invention, the TIG welding which does not have the fault which said each welding method has but does not use a filler metal is employ | adopted. In the TIG welding of an aluminum plate material, AC TIG welding is generally used in order not to damage the electrode and to remove the oxide film on the surface of the aluminum material. However, AC TIG welding has a drawback in that the bonding speed cannot be increased because the polarity of the current needs to be alternately reversed between minus and plus on the principle.
一方、直流のティグ溶接には、電極がプラスの逆極性ティグ溶接と電極がマイナスの直流正極性ティグ溶接の２種類がある。いずれもアルミニウム合金の溶接には適用されておらず、主に鉄鋼材料に用いられる方法として知られている。電極がプラスの逆極性ティグの場合には、交流ティグ同様にクリーニング効果は発揮されるが電極への入熱量が大きいため電極自体の消耗が激しくなり、陰極点が母材表面を走り入熱が分散されるため溶け込みも浅くなる。このように、逆極性ティグは、良好な溶接状態を長時間維持できないために、工業的に適用するには困難である。 On the other hand, there are two types of DC TIG welding: reverse polarity TIG welding with a positive electrode and DC positive polarity TIG welding with a negative electrode. None of them are applied to the welding of aluminum alloys, and are known as methods mainly used for steel materials. When the electrode is a positive reverse polarity TIG, the cleaning effect is exhibited as in the AC TIG, but the heat input to the electrode is large, so that the electrode itself is consumed violently. Dispersion is shallow due to dispersion. Thus, the reverse polarity TIG is difficult to apply industrially because it cannot maintain a good welding state for a long time.
一方、電極がマイナスの直流正極性ティグ溶接の場合には、電極への負荷が低く消耗も少ないという利点があり、深い溶け込みが得られるため５００Ａ以上の電流を必要とする大電流ティグ溶接に用いられることもある。しかしながら、クリーニング作用が発揮されないため溶接金属内部と表面部に欠陥が生じ易く
、これまた工業的に適用するには困難であった。しかしながら、本発明者は、溶接金属内部と表面部における欠陥発生の防止について種々検討を重ねた結果、所定要件を満たすことにより直流正極性ティグ溶接をアルミニウム合金に適用可能とすることを見出し、本発明を完成するに至った。
On the other hand, when the electrode is negative DC positive polarity TIG welding, there is an advantage that the load on the electrode is low and consumption is small, and since deep penetration is obtained, it is used for large current TIG welding that requires a current of 500 A or more. Sometimes. However, since the cleaning action is not exhibited, defects are easily generated in the weld metal and on the surface portion, which is difficult to apply industrially. However, as a result of various studies on the prevention of defects in the weld metal and on the surface portion, the present inventor has found that DC positive polarity TIG welding can be applied to an aluminum alloy by satisfying predetermined requirements. The invention has been completed.
Ｂ．アルミニウム板材
本発明に用いるアルミニウム板材は、厚さ０．５〜３．０ｍｍを有する。アルミニウム板材の厚さが０．５ｍｍ未満では、板材として用いるには薄く強度や剛性などが不足する。更に、板厚全てを溶け込ませた貫通溶接を実施時には、溶け落ちや周囲の熱影響部の変形発生といった問題が生じる。板厚が３．０ｍｍを超えると、薄板の範疇を超える厚さとなり重量も増加するので用いられない。更に、板厚全てを溶け込ませた貫通溶接を実施時には溶接時の入熱を高くする必要があるため、やはり周囲の熱影響部の変形発生といった問題が生じる。従って、本発明では、アルミニウム板材の厚さを０．５〜３．０ｍｍに規定する。
B. Aluminum plate The aluminum plate used in the present invention has a thickness of 0.5 to 3.0 mm. If the thickness of the aluminum plate is less than 0.5 mm, it is thin and insufficient in strength and rigidity for use as a plate. Furthermore, when carrying out penetration welding in which the entire plate thickness is melted, problems such as melting off and deformation of the surrounding heat-affected zone occur. If the plate thickness exceeds 3.0 mm, the thickness exceeds the category of the thin plate and the weight increases, so that it is not used. Furthermore, since it is necessary to increase the heat input at the time of welding when carrying out through welding in which the entire plate thickness is melted, there also arises a problem that the surrounding heat-affected zone is deformed. Therefore, in the present invention, the thickness of the aluminum plate is specified to be 0.5 to 3.0 mm.
アルミニウム板材の材質としては、Ｍｇ：１．５ｍａｓｓ％以下を含有するＡｌ合金が用いられるが、以下に示す成分範囲において、より良好な生産性と、表面平滑性や耐欠陥性により優れた溶接方法となる。成分組成「ｍａｓｓ％」については、以下において単に「％」と記す。なお、上記Ａｌ合金の他に、純度９９．５ｍａｓｓ％以上の純Ａｌも用いることができる。 As the material of the aluminum plate, an Al alloy containing Mg: 1.5 mass% or less is used. In the component ranges shown below, the welding method is more excellent in productivity, surface smoothness and defect resistance. It becomes. The component composition “mass%” is simply referred to as “%” in the following. In addition to the Al alloy, pure Al having a purity of 99.5 mass% or more can also be used.
Ｍｇ：Ａｌ合金中のＭｇは、含有量が増えれば強度を向上させる元素である。ＳｉとＭｇ２Ｓｉを形成することによって、強度向上に寄与するものである。しかしながら、溶接時の欠陥発生の要因にもなりうる元素でもある。交流ティグ（ＴＩＧ）溶接においても欠陥の発生の問題となるが、クリーニング作用の無い直流正極性ティグにおいてはその影響は更に大きい。そのため、Ｍｇ添加量が１．５％を超えると、内部欠陥及びビード表面へのピット等の欠陥となる。したがって、Ｍｇの添加量は１．５％以下とし、好ましくは１．３％以下とする。本発明においてＭｇは、強度を犠牲にしても欠陥発生の防止を優先させる場合は添加しなくてもよい。 Mg: Mg in the Al alloy is an element that improves the strength as the content increases. By forming Si and Mg 2 Si, it contributes to strength improvement. However, it is also an element that can cause defects during welding. In AC TIG (TIG) welding, there is a problem of generation of defects, but in DC positive polarity TIG having no cleaning action, the influence is even greater. Therefore, if the amount of Mg added exceeds 1.5%, internal defects and defects such as pits on the bead surface are caused. Therefore, the amount of Mg added is 1.5% or less, preferably 1.3% or less. In the present invention, Mg may not be added if priority is given to preventing the occurrence of defects at the expense of strength.
Ｓｉ：Ｍｇと同時に存在するとＭｇ２Ｓｉを形成して合金の強度を向上させるため、意図的に添加してもよい。本発明において、Ｓｉは選択的添加元素である。添加量が増加すると板材への加工が困難となるので、Ｓｉ添加量は２．０％以下とし、好ましくは１．５％以下とする。なお、意図的に添加するのではなく、上述の不可避的不純物として含有されていてもよい。 If present together with Si: Mg, Mg 2 Si is formed to improve the strength of the alloy, so it may be added intentionally. In the present invention, Si is a selective additive element. Since processing to a plate material becomes difficult when the addition amount increases, the Si addition amount is set to 2.0% or less, preferably 1.5% or less. In addition, it does not add intentionally and may contain as the above-mentioned unavoidable impurity.
Ｆｅ：Ｆｅの添加によりＡｌ合金中にＡｌ−Ｆｅ系の化合物が形成され合金の強度を向上させるため、意図的に添加してもよい。本発明において、Ｆｅは選択的添加元素である。添加量が増加すると板材への加工が困難となるので、Ｆｅ添加量は１．０％以下とし、好ましくは、０．７％以下とする。なお、意図的に添加するのではなく、上述の不可避的不純物として含有されていてもよい。 Fe: The addition of Fe may form an Al—Fe compound in the Al alloy and improve the strength of the alloy. In the present invention, Fe is a selective additive element. If the amount added is increased, processing into a plate material becomes difficult, so the amount of Fe added is 1.0% or less, preferably 0.7% or less. In addition, it does not add intentionally and may contain as the above-mentioned unavoidable impurity.
Ｃｕ：ＣｕはＡｌマトリックスに固溶し、固溶体中の溶質の過飽和度を上げる等して強度を付与するため、意図的に添加してもよい。本発明において、Ｃｕは選択的添加元素である。Ｃｕの添加量が０．５％を超えると、板材への加工が困難になり、更に、強度は向上するものの耐食性や溶接割れも発生する危険性が生じる。したがって、Ｃｕ添加量は０．５％以下とし、好ましくは０．３％以下とする。なお、意図的に添加するのではなく、上述の不可避的不純物として含有されていてもよい。 Cu: Cu dissolves in the Al matrix and imparts strength by increasing the degree of supersaturation of the solute in the solid solution, so it may be added intentionally. In the present invention, Cu is a selective additive element. When the added amount of Cu exceeds 0.5%, it becomes difficult to process the plate material, and further, although the strength is improved, there is a risk that corrosion resistance and weld cracking occur. Therefore, the Cu addition amount is 0.5% or less, preferably 0.3% or less. In addition, it does not add intentionally and may contain as the above-mentioned unavoidable impurity.
Ｍｎ：Ａｌ合金中のＭｎは耐食性を低下することなく強度を向上させるため、意図的に添加してもよい。本発明において、Ｍｎは選択的添加元素である。２．０％を超えて添加すると、鋳造中に巨大な金属間化合物を生成し、Ａｌ合金の機械的性質を低下させる原因となる。したがって、Ｍｎ添加量は２．０％以下とし、好ましくは１．５％以下とする。なお、意図的に添加するのではなく、上述の不可避的不純物として含有されていてもよい。
なお、これらＳｉ、Ｆｅ、Ｃｕ、Ｍｎの選択的添加元素は、１種又は２種以上が添加される。
Mn: Mn in the Al alloy may be intentionally added in order to improve the strength without reducing the corrosion resistance. In the present invention, Mn is a selective additive element. If added over 2.0%, a huge intermetallic compound is formed during casting, which causes the mechanical properties of the Al alloy to deteriorate. Therefore, the amount of Mn added is 2.0% or less, preferably 1.5% or less. In addition, it does not add intentionally and may contain as the above-mentioned unavoidable impurity.
In addition, 1 type, or 2 or more types are added for the selective addition element of these Si, Fe, Cu, and Mn.
Ｃｒ：本発明の効果を損なわない範囲において、不純物レベルのＣｒが少量含有されていてもよい。Ｃｒの微細な析出物は、熱間加工の際に発生する結晶粒の粗大化を抑制する作用を有する。０．２％を超えて含有されると鋳造中に巨大な金属間化合物を生成し、Ａｌ合金の機械的性質を低下させる原因になる。したがって、Ｃｒ含有量は０．２％以下とし、好ましくは０．１％以下である。 Cr: As long as the effects of the present invention are not impaired, a small amount of Cr at the impurity level may be contained. The fine precipitates of Cr have an effect of suppressing the coarsening of crystal grains generated during hot working. If the content exceeds 0.2%, a huge intermetallic compound is produced during casting, which causes the mechanical properties of the Al alloy to deteriorate. Therefore, the Cr content is 0.2% or less, preferably 0.1% or less.
Ｚｎ：本発明の効果を損なわない範囲において、不純物レベルのＺｎが少量含有されていてもよい。Ｚｎは強度向上に寄与する元素でもあるが、耐食性や耐応力腐食割れ性を低下させる元素でもある。したがって、Ｚｎの含有量は０．３％以下とし、好ましくは０．２５％以下である。 Zn: As long as the effects of the present invention are not impaired, a small amount of Zn at an impurity level may be contained. Zn is an element that contributes to strength improvement, but is also an element that lowers corrosion resistance and stress corrosion cracking resistance. Therefore, the Zn content is 0.3% or less, preferably 0.25% or less.
Ｔｉ：本発明の効果を損なわない範囲において、不純物レベルのＴｉが少量含有されていてもよい。Ｔｉは鋳造組織を微細化し、合金の強度や靭性を向上させる元素ではあるが、０．２％を超えて含有されると粗大化合物を形成し、板材への加工が困難になるだけでなく強度低下や靭性低下を招く。したがって、Ｔｉの含有量は０．２％以下とし、好ましいくは０．１５％以下である。
なお、これらＣｒ、Ｚｎ、Ｔｉは、１種又は２種以上が添加される。これら不純物レベルの元素は、上記選択的添加元素と共に添加されてもよく、選択的添加元素を添加せずにこれら不純物レベルの元素のみを添加してもよい。
Ti: As long as the effects of the present invention are not impaired, a small amount of impurity level Ti may be contained. Ti is an element that refines the cast structure and improves the strength and toughness of the alloy, but if it exceeds 0.2%, it forms a coarse compound, which makes it difficult to process into a plate material as well as strength. This leads to reduction and toughness reduction. Therefore, the Ti content is 0.2% or less, preferably 0.15% or less.
In addition, 1 type, or 2 or more types are added for these Cr, Zn, and Ti. These impurity level elements may be added together with the selective additive element, or only the impurity level element may be added without adding the selective additive element.
Ｃ．直流正極性ティグ溶接
本発明で用いる直流正極性ティグ溶接の条件について、下記に詳述する。
C. DC positive polarity TIG welding The conditions of DC positive polarity TIG welding used in the present invention are described in detail below.
Ｃ−１．シールドガス
ティグ溶接におけるシールドガスとして、純度１００％Ｈｅを用いると大きな溶け込みが得られることが知られている。しかしながら、ティグ溶接におけるシールドガスとして一般に用いられるＡｒに比べてＨｅは比重が約１／１０と小さいので、Ｈｅのプラズマ気流がＡｒのプラズマ気流に比べて弱く、更に、ＨｅはＡｒに比べてシールド性に劣るなど、Ａｒに比べてＨｅはシールドガスとして不利であった。このように、シールドガスにＨｅを使用することは汎用的なティグ溶接では実用的ではないとされていた。本発明者は、直流正極性ティグ溶接におけるシールドガスとしてＨｅを用いる際の適正条件を見出すことによって、ティグ溶接におけるシールドガスとしてのＨｅの不利な点を克服した。
本発明で用いるシールドガスは、純度７５〜１００％のＨｅである。純度が７５％未満では、十分な溶け込み効果が得られない。シールドガスとしてのＨｅ純度は、好ましくは
９０〜１００％である。
C-1. Shielding gas It is known that large penetration can be obtained when 100% He is used as shielding gas in TIG welding. However, since He has a specific gravity as small as about 1/10 compared to Ar, which is generally used as a shielding gas in TIG welding, the He plasma stream is weaker than the Ar plasma stream, and He is shielded compared to Ar. He was disadvantageous as a shielding gas compared to Ar, such as poor in properties. As described above, it has been considered that the use of He for the shielding gas is not practical in general-purpose TIG welding. The present inventor has overcome the disadvantages of He as a shielding gas in TIG welding by finding appropriate conditions when using He as a shielding gas in DC positive polarity TIG welding.
The shielding gas used in the present invention is He having a purity of 75 to 100%. If the purity is less than 75%, a sufficient penetration effect cannot be obtained. The He purity as the shielding gas is preferably 90 to 100%.
Ｃ−２．シールドガスの流量
直流正極性ティグ溶接において、純度７５〜１００％のＨｅの流量が５リットル／分未満では、シールドガスによるシールド効果が得られないことが判明した。一方、１５リットル／分を超えると、シールド効果は得られるものの、凝固前の溶接金属部にＨｅが強く押し当たることによって、溶接金属部表面がシールドガスの圧力に押されてへこみ、溶接面の平滑が維持できなくなることが判明した。そこで、シールドガスの流量を５〜１５リットル／分に設定することによって溶接部のシールド効果と溶接面の平滑性の両立が可能となった。本発明では、直流正極性ティグ溶接において純度７５〜１００％のＨｅの流量を５〜１５リットル／分とする。
C-2. Shielding gas flow rate In direct current positive polarity TIG welding, it was found that if the flow rate of He with a purity of 75 to 100% is less than 5 liters / minute, the shielding effect by the shielding gas cannot be obtained. On the other hand, if it exceeds 15 liters / minute, the shielding effect is obtained, but when the He is strongly pressed against the weld metal part before solidification, the surface of the weld metal part is pressed by the pressure of the shield gas and dents, so that the weld surface It was found that smoothness could not be maintained. Therefore, by setting the flow rate of the shielding gas to 5 to 15 liters / minute, it is possible to achieve both the shielding effect of the welded portion and the smoothness of the weld surface. In the present invention, the flow rate of He having a purity of 75 to 100% is set to 5 to 15 liters / minute in DC positive polarity TIG welding.
Ｃ−３．電極間距離
直流正極性ティグ溶接における溶け込みやシールド効果は、タングステン電極と被溶接材であるアルミニウム板材の距離によって影響を受けることが判明した。すなわち、タングステン電極とアルミニウム板材の距離が１．０ｍｍを超えると、適正な溶け込み状態が得られず、かつ、Ｈｅによるシールド効果が得られず、良好な溶接が達成できないことが判明した。そこで、タングステン電極とアルミニウム板材の距離を１．０ｍｍ以下に設定することによって、溶接金属の適正な溶け込みと溶接部におけるシールド効果との両立が可能となった。本発明では、直流正極性ティグ溶接において、タングステン電極とアルミニウム板材の電極間距離を１．０ｍｍ以下とする。上記効果を更に高めるには、電極間距離を０．５ｍｍ以下とするのが好ましい。操作上においてタングステン電極を移動させる際に、被溶接材であるアルミニウム板材に接触させずに移動させるには、タングステン電極とアルミニウム板材とが少なくとも０．１ｍｍ離間していることが望ましい。そこで、電極間距離の下限は０．１ｍｍとするのが好ましい。
C-3. Interelectrode distance It has been found that the penetration and shielding effect in DC positive polarity TIG welding is affected by the distance between the tungsten electrode and the aluminum plate material to be welded. That is, it has been found that if the distance between the tungsten electrode and the aluminum plate exceeds 1.0 mm, an appropriate penetration state cannot be obtained, and the shielding effect by He cannot be obtained, so that good welding cannot be achieved. Therefore, by setting the distance between the tungsten electrode and the aluminum plate to 1.0 mm or less, it is possible to achieve both the proper penetration of the weld metal and the shielding effect at the weld. In the present invention, in DC positive polarity TIG welding, the distance between the tungsten electrode and the aluminum plate is set to 1.0 mm or less. In order to further enhance the above effect, the distance between the electrodes is preferably 0.5 mm or less. When the tungsten electrode is moved in operation, it is desirable that the tungsten electrode and the aluminum plate are separated from each other by at least 0.1 mm in order to move the tungsten electrode without being in contact with the aluminum plate as a material to be welded. Therefore, the lower limit of the distance between the electrodes is preferably 0.1 mm.
Ｃ−４．溶接時における入熱量
直流正極性ティグ溶接の溶接時における入熱量について検討した。直流正極性ティグ溶接において、溶接電圧Ｅ（Ｖ）、電流Ｉ（Ａ）、溶接速度ｖ（ｃｍ／分）とするとき、溶接部の単位長さ（１ｃｍ）当たりに発生する電気的エネルギーＨは、Ｈ＝（６０・Ｅ・Ｉ）／ｖ（ジュール＜Ｊ＞／ｃｍ）で表される。この電気的エネルギーＨを、アルミニウム板材の板厚ｔ（ｃｍ）で割ることにより、アルミニウム板材の単位厚さ当たりの入熱量Ｈ‘が得られる。すなわち、Ｈ‘＝（６０・Ｅ・Ｉ）／ｖ・ｔ（Ｊ／ｃｍ２）となる。
C-4. Heat input during welding We investigated the heat input during welding in DC positive polarity TIG welding. In DC positive polarity TIG welding, when the welding voltage E (V), current I (A), and welding speed v (cm / min), the electrical energy H generated per unit length (1 cm) of the weld is , H = (60 · E · I) / v (joule <J> / cm). By dividing this electrical energy H by the plate thickness t (cm) of the aluminum plate, a heat input amount H ′ per unit thickness of the aluminum plate is obtained. That is, H ′ = (60 · E · I) / v · t (J / cm 2 ).
本発明者は、アルミニウム板材の厚さを貫通させるに十分な溶け込みが得られ、かつ、歪みや反りの少ない平滑な接合が得られるＨ‘の範囲を検討したところ、２５００〜１００００（Ｊ／ｃｍ２）の範囲であることを実験的に見出した。Ｈ‘が２５００（Ｊ／ｃｍ２）未満では入熱量不足で十分な溶け込みが得られない。一方、Ｈ‘が１００００（Ｊ／ｃｍ２）を超えると、入熱量過剰で接合部に溶け落ちが発生したり熱変形が生じる。更に十分な溶け込みと平滑性を得るには、Ｈ‘を２５００〜８０００（Ｊ／ｃｍ２）とするのが好ましい。 The present inventor has examined the range of H ′ in which sufficient melting to penetrate the thickness of the aluminum plate material can be obtained and smooth bonding with less distortion and warpage can be obtained. 2500 to 10,000 (J / cm It was found experimentally that it was in the range of 2 ). When H ′ is less than 2500 (J / cm 2 ), sufficient penetration cannot be obtained due to insufficient heat input. On the other hand, if H ′ exceeds 10,000 (J / cm 2 ), the heat input will be excessive and the joint will melt and heat deformation will occur. Furthermore, in order to obtain sufficient penetration and smoothness, H ′ is preferably 2500 to 8000 (J / cm 2 ).
以下、実施例に基づき本発明を更に詳細に説明するが、本発明はこれに限定されるものではない。 EXAMPLES Hereinafter, although this invention is demonstrated still in detail based on an Example, this invention is not limited to this.
（実施例１）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ３．０ｍｍのアルミニウム平板（ＪＩＳ Ａ１０５０Ｐ−Ｈ１２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材との電極間距離０．３ｍｍとし、シールドガスは純度１００％のＨｅを流量１４リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、２８００（Ｊ／ｃｍ２）となった。
Example 1
As a material to be welded, two aluminum flat plates (JIS A1050P-H12) having a width of 1500 mm, a length of 3000 mm, and a thickness of 3.0 mm were prepared. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment for welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions where the entire plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the electrodes of the tungsten electrode and the material to be welded was 0.3 mm, and the shielding gas was He at a flow rate of 14 liters / min. The heat input per unit thickness (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula and was 2800 (J / cm 2 ).
（実施例２）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ１．５ｍｍのアルミニウム平板（ＪＩＳ Ａ１１００Ｐ−Ｏ）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流８０Ａ、溶接速度８０ｃｍ／分、タングステン電極と被溶接材の距離０．８ｍｍとし、シールドガスは純度１００％のＨｅを流量８リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、６８００（Ｊ／ｃｍ２）となった。
(Example 2)
Two aluminum flat plates (JIS A1100P-O) having a width of 1500 mm, a length of 3000 mm, and a thickness of 1.5 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 80 A, the welding speed was 80 cm / min, the distance between the tungsten electrode and the material to be welded was 0.8 mm, and the shielding gas was He at a purity of 100% at a flow rate of 8 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 6800 (J / cm 2 ).
（実施例３）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ０．５ｍｍのアルミニウム平板（ＪＩＳ Ａ３００３Ｐ−Ｈ１２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧２０Ｖ、溶接電流３０Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離１．０ｍｍとし、シールドガスは純度１００％のＨｅを流量５リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７６００（Ｊ／ｃｍ２）となった。
(Example 3)
Two aluminum flat plates (JIS A3003P-H12) having a width of 1500 mm, a length of 3000 mm, and a thickness of 0.5 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 20 V, the welding current was 30 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 1.0 mm, and the shielding gas was He having a purity of 100% at a flow rate of 5 liters / min. The amount of heat input per unit thickness (H ′) of the aluminum plate at this time was calculated from the above formula, and was 7600 (J / cm 2 ).
（実施例４）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
Example 4
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（実施例５）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ１．２ｍｍのアルミニウム平板（ＪＩＳ Ａ６０２２Ｐ−Ｔ４）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．８ｍｍとし、シールドガスは純度１００％のＨｅを流量１０リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７０００（Ｊ／ｃｍ２）となった。
(Example 5)
Two aluminum flat plates (JIS A6022P-T4) having a width of 1500 mm, a length of 3000 mm, and a thickness of 1.2 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.8 mm, and the shielding gas was He at a flow rate of 10 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula and was 7000 (J / cm 2 ).
（実施例６）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは８５％Ｈｅ−１５％Ａｒの混合ガスを流量８リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Example 6)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage is 30 V, the welding current is 78 A, the welding speed is 95 cm / min, the distance between the tungsten electrode and the material to be welded is 0.5 mm, and the shielding gas is a flow of 85% He-15% Ar mixed gas at a flow rate of 8 liters / min. did. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（実施例７）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００３Ｐ−Ｈ１２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧２５Ｖ、溶接電流１１０Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量１０リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、８７００（Ｊ／ｃｍ２）となった。
(Example 7)
Two aluminum flat plates (JIS A3003P-H12) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 25 V, the welding current was 110 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 10 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 8700 (J / cm 2 ).
（実施例８）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧２５Ｖ、溶接電流１２５Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離１．０ｍｍとし、シールドガスは１００％Ｈｅガスを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、９９００（Ｊ／ｃｍ２）となった。
(Example 8)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 25 V, the welding current was 125 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 1.0 mm, and 100% He gas was flowed at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 9900 (J / cm 2 ).
（比較例１）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ５０５２Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流８０Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７６００（Ｊ／ｃｍ２）となった。
(Comparative Example 1)
As a material to be welded, two aluminum flat plates (JIS A5052P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 80 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 9 liters / min. The amount of heat input per unit thickness (H ′) of the aluminum plate at this time was calculated from the above formula, and was 7600 (J / cm 2 ).
（比較例２）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ１．６ｍｍのアルミニウム平板（ＪＩＳ Ａ５１８２Ｐ−Ｏ）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流８０Ａ、溶接速度８０ｃｍ／分、タングステン電極と被溶接材の距離０．８ｍｍとし、シールドガスは純度１００％のＨｅを流量８リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、６４００（Ｊ／ｃｍ２）となった。
(Comparative Example 2)
Two aluminum flat plates (JIS A5182P-O) having a width of 1500 mm, a length of 3000 mm, and a thickness of 1.6 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 80 A, the welding speed was 80 cm / min, the distance between the tungsten electrode and the material to be welded was 0.8 mm, and the shielding gas was He at a purity of 100% at a flow rate of 8 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 6400 (J / cm 2 ).
（比較例３）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ０．３ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流２５Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、８９００（Ｊ／ｃｍ２）となった。
(Comparative Example 3)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 0.3 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 25 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 8900 (J / cm 2 ).
（比較例４）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、交流ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧１７Ｖ、溶接電流９５Ａ、溶接速度４０ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、１２０００（Ｊ／ｃｍ２）となった。
(Comparative Example 4)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These materials to be welded were formed into joined bodies having a width of 3000 mm and a length of 3000 mm using an alternating current TIG welding method. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 17 V, the welding current was 95 A, the welding speed was 40 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a purity of 100% at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula and was 12000 (J / cm 2 ).
（比較例５）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離１．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Comparative Example 5)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 1.5 mm, and the shielding gas was He at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（比較例６）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量２０リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Comparative Example 6)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 20 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（比較例７）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは５０％Ａｒ−５０％Ｈｅの混合ガスを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Comparative Example 7)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage is 30 V, the welding current is 78 A, the welding speed is 95 cm / min, the distance between the tungsten electrode and the material to be welded is 0.5 mm, and the shielding gas is a mixed gas of 50% Ar-50% He at a flow rate of 9 liters / min. did. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（比較例８）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％Ａｒを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Comparative Example 8)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was 100% Ar at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
（比較例９）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流２１Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％Ｈｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、２０００（Ｊ／ｃｍ２）となった。
(Comparative Example 9)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 21 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was 100% He at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula and was 2000 (J / cm 2 ).
（比較例１０）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流１２５Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％Ｈｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、１２０００（Ｊ／ｃｍ２）となった。
(Comparative Example 10)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 125 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was 100% He at a flow rate of 9 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula and was 12000 (J / cm 2 ).
（比較例１１）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ５．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流２７０Ａ、溶接速度３０ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量９リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、３２４００（Ｊ／ｃｍ２）となった。
(Comparative Example 11)
As a material to be welded, two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 5.0 mm were prepared. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 270 A, the welding speed was 30 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He at a flow rate of 9 liters / min. The amount of heat input per unit thickness (H ′) of the aluminum plate at this time was calculated from the above formula and was 32400 (J / cm 2 ).
（比較例１２）
被溶接材として、幅１５００ｍｍ、長さ３０００ｍｍ、厚さ２．０ｍｍのアルミニウム平板（ＪＩＳ Ａ３００４Ｐ−Ｈ３２）を２枚用意した。それぞれの被溶接材の長辺同士を突合せた。これらの被溶接材を、溶加材を用いない直流正極性ティグ溶接法を用いて幅３０００ｍｍ、長さ３０００ｍｍの接合体とした。溶接時の前処理として酸化皮膜の一般的な除去を行い、溶接条件は板厚全てが溶ける完全溶け込み条件を選定した。すなわち、溶接電圧３０Ｖ、溶接電流７８Ａ、溶接速度９５ｃｍ／分、タングステン電極と被溶接材の距離０．５ｍｍとし、シールドガスは純度１００％のＨｅを流量４リットル／分で流した。このときのアルミニウム板材の単位厚さ当たりの入熱量（Ｈ‘）を上記式より計算すると、７４００（Ｊ／ｃｍ２）となった。
(Comparative Example 12)
Two aluminum flat plates (JIS A3004P-H32) having a width of 1500 mm, a length of 3000 mm, and a thickness of 2.0 mm were prepared as materials to be welded. The long sides of each workpiece were butted together. These welded materials were formed into a joined body having a width of 3000 mm and a length of 3000 mm by using a direct current positive polarity TIG welding method that does not use a filler material. As a pretreatment at the time of welding, general removal of the oxide film was performed, and the welding conditions were selected as complete penetration conditions in which all the plate thickness was melted. That is, the welding voltage was 30 V, the welding current was 78 A, the welding speed was 95 cm / min, the distance between the tungsten electrode and the material to be welded was 0.5 mm, and the shielding gas was He having a purity of 100% at a flow rate of 4 liters / min. The amount of heat input (H ′) per unit thickness of the aluminum plate at this time was calculated from the above formula, and was 7400 (J / cm 2 ).
上記の実施例及び比較例に用いた合金組成を表1に示す。また、溶接条件、ならびに、溶接部の表面状態と断面状態を下記のように評価した結果を表２に示す。 Table 1 shows the alloy compositions used in the above Examples and Comparative Examples. Table 2 shows the results of evaluating the welding conditions and the surface state and cross-sectional state of the weld as follows.
（溶接部の表面状態の評価）
溶接部の表面状態は、目視観察によって評価した。目視により、平滑性が得られていた場合を合格とした。目視により、ピット状の欠陥、溶け落ち、平滑性を損なう程の激しい凹凸、溶け込み不足のいずれかが観察された場合を不合格とした。
(Evaluation of the surface condition of the weld)
The surface state of the weld was evaluated by visual observation. A case where smoothness was obtained by visual inspection was regarded as acceptable. A case where any of pit-like defects, melt-out, severe irregularities that impair smoothness, and insufficient penetration was observed by visual inspection was regarded as unacceptable.
（溶接部の断面状態の評価）
溶接部の断面状態は、目視観察によって評価した。目視により、欠陥が観察されなかった場合を合格とした。目視により、気泡状の欠陥や割れが観察された場合を不合格とした。
(Evaluation of the cross-sectional state of the weld)
The cross-sectional state of the welded portion was evaluated by visual observation. The case where no defect was observed by visual inspection was regarded as acceptable. The case where a bubble-like defect and a crack were observed by visual observation was made disqualified.
（総合評価）
溶接部における表面状態及び断面状態のいずれもが合格の場合を、総合評価が合格（○とした。表面状態と断面状態の少なくともいずれかが不合格の場合を、総合評価が不合格（×）とした。
(Comprehensive evaluation)
When the surface state and the cross-sectional state at the welded part are both acceptable, the overall evaluation is acceptable (circled. When at least one of the surface state and the cross-sectional state is unacceptable, the overall evaluation is unacceptable (×)). It was.
実施例１〜８では、溶接部における表面状態及び断面状態のいずれもが合格であり、総合評価が合格であった。実施例４、５に示す接合体の断面図を、図１、２にそれぞれ示す。図１、２において、１は接合する二枚のアルミニウム板材、２は溶接部の表面、３は溶接部の断面を示す。これら図から明らかなように、溶接部の表面状態は良好な平滑性を示し、溶接部の断面状態に欠陥はない。
In Examples 1 to 8, both the surface state and the cross-sectional state in the welded portion were acceptable, and the overall evaluation was acceptable. 1 and 2 are sectional views of the joined bodies shown in Examples 4 and 5, respectively. 1 and 2,
比較例１では、アルミニウム板材に含有されるＭｇ量が多過ぎたため、溶接部における表面状態及び断面状態のいずれもが不合格であり、総合評価が不合格となった。なお、接合体の断面図を図３に示す。図３において、１〜３は図１、２と同じである。４は表面のピット状欠陥、５は断面の気泡状欠陥である。図から明らかなように、溶接部の表面にはピット状の欠陥があり、溶接部の断面には気泡状の欠陥が見られる。
比較例２では、アルミニウム板材に含有されるＭｇ量が多過ぎたため、溶接部における表面状態及び断面状態のいずれもが不合格であり、総合評価が不合格となった。
比較例３では、アルミニウム板材の厚さが薄過ぎ、溶接部に溶け落ち（穴あき）が発生し接合できなかったため、表面状態は無論、不合格であり、断面状態の評価については、溶接板として成り立たないため評価しなかった。その結果、総合評価は不合格となった。
比較例４では、直流正極性ティグ溶接法を用いず、入熱量も多過ぎたため、溶接部における表面状態は凹凸が激しく不合格であった。断面状態の評価については、凹凸により平滑板として成り立たないため評価しなかった。その結果、総合評価は不合格となった。
比較例５では、電極間距離が長過ぎたため、溶接条件選定時は板厚全てが溶け込んでいたが、溶接長３０００ｍｍでは部分的に溶け込み不足が生じ表面状態が不合格であった。断面状態の評価については、接合板として成り立たないため評価できなかった。その結果、総合評価は不合格となった。
比較例６では、シールドガスの流量が多過ぎたため、溶接部における表面状態は凹凸が激しく不合格であった。断面状態の評価については、凹凸により平滑板として成り立たないため評価しなかった。その結果、総合評価は不合格となった。
比較例７では、シールドガスのＨｅ含有量が少な過ぎたため、溶接部における表面状態及び断面状態のいずれもが不合格であり、総合評価が不合格となった。
比較例８では、シールドガスにＡｒを用いたため、溶接部における表面状態及び断面状態のいずれもが不合格であり、総合評価が不合格となった。なお、接合体の断面図を図４に示す。図４において、１〜５は図３と同じである。図から明らかなように、溶接部の表面にはピット状の欠陥があり、溶接部の断面には気泡状の欠陥が見られる。
比較例９では、入熱量が少な過ぎたため、溶接条件選定時は板厚全てが溶け込んでいたが、溶接長３０００ｍｍでは部分的に溶け込み不足が生じ表面状態が不合格であった。断面状態の評価については、接合板として成り立たないため評価しなかった。その結果、総合評価は不合格となった。
比較例１０では、入熱量が多過ぎたため、溶接部に溶け落ち（穴あき）が発生し接合できなかったため、表面状態は無論、不合格であり、断面状態の評価については、溶接板として成り立たないため評価できなかった。その結果、総合評価は不合格となった。
比較例１１では、アルミニウム板材の厚さが厚過ぎ、溶接部における表面状態は凹凸が激しく不合格であった。断面状態の評価については、凹凸により平滑板として成り立たないため評価しなかった。その結果、総合評価は不合格となった。また、薄板範疇を超えた厚さのアルミニウム板材を接合したので、入熱量は本発明で規定する上限値の３倍以上となった。
比較例１２では、シールドガスの流量が少な過ぎたためシールド不十分であった。溶接条件選定時は顕著でなかったものの、溶接長３０００ｍｍでは溶接部表面が黒色化するとともにピット状の欠陥が発生した。したがって表面状態が不合格のため断面状態の評価については、接合板として成り立たないため評価できなかった。その結果、総合評価は不合格となった。
In Comparative Example 1, since the amount of Mg contained in the aluminum plate was too much, both the surface state and the cross-sectional state in the welded part were rejected, and the comprehensive evaluation was rejected. A cross-sectional view of the joined body is shown in FIG. In FIG. 3, 1 to 3 are the same as FIGS. 4 is a surface pit-like defect, and 5 is a cross-sectional bubble-like defect. As is apparent from the figure, there are pit-like defects on the surface of the welded portion, and bubble-like defects are seen on the cross section of the welded portion.
In Comparative Example 2, since the amount of Mg contained in the aluminum plate material was too large, both the surface state and the cross-sectional state in the welded part were rejected, and the comprehensive evaluation was rejected.
In Comparative Example 3, the thickness of the aluminum plate was too thin, and the welded portion was melted (perforated) and could not be joined. Therefore, the surface state was, of course, rejected. I did not evaluate because it does not hold as. As a result, the overall evaluation was rejected.
In Comparative Example 4, the DC positive polarity TIG welding method was not used, and the heat input was too much, so that the surface state at the welded portion was severely uneven and rejected. The evaluation of the cross-sectional state was not evaluated because it was not realized as a smooth plate due to unevenness. As a result, the overall evaluation was rejected.
In Comparative Example 5, since the distance between the electrodes was too long, the entire plate thickness was melted when the welding conditions were selected. However, when the weld length was 3000 mm, the melt was partially insufficient and the surface condition was unacceptable. The evaluation of the cross-sectional state could not be evaluated because it did not hold as a joining plate. As a result, the overall evaluation was rejected.
In Comparative Example 6, since the flow rate of the shielding gas was too large, the surface state at the welded portion was severely uneven and rejected. The evaluation of the cross-sectional state was not evaluated because it was not realized as a smooth plate due to unevenness. As a result, the overall evaluation was rejected.
In comparative example 7, since there was too little He content of shielding gas, both the surface state and cross-sectional state in a welding part failed, and comprehensive evaluation failed.
In Comparative Example 8, since Ar was used as the shielding gas, both the surface state and the cross-sectional state in the welded portion were rejected, and the comprehensive evaluation was rejected. A cross-sectional view of the joined body is shown in FIG. 4, 1 to 5 are the same as those in FIG. As is apparent from the figure, there are pit-like defects on the surface of the welded portion, and bubble-like defects are seen on the cross section of the welded portion.
In Comparative Example 9, since the heat input was too small, the entire plate thickness was melted when the welding conditions were selected. However, when the welding length was 3000 mm, the melt was partially insufficient and the surface condition was unacceptable. The evaluation of the cross-sectional state was not evaluated because it did not hold as a bonded plate. As a result, the overall evaluation was rejected.
In Comparative Example 10, since the amount of heat input was too large, the welded portion was melted (perforated) and could not be joined. Therefore, the surface state was, of course, rejected, and the evaluation of the cross-sectional state was established as a welded plate. It was not possible to evaluate because there was not. As a result, the overall evaluation was rejected.
In Comparative Example 11, the thickness of the aluminum plate was too thick, and the surface state at the welded portion was severely uneven and rejected. The evaluation of the cross-sectional state was not evaluated because it was not realized as a smooth plate due to unevenness. As a result, the overall evaluation was rejected. Moreover, since the aluminum plate material having a thickness exceeding the thin plate category was joined, the heat input amount was three times or more the upper limit value defined in the present invention.
In Comparative Example 12, the shield gas was insufficient because the flow rate of the shield gas was too small. Although not remarkable when selecting the welding conditions, at the welding length of 3000 mm, the surface of the welded portion was blackened and pit-like defects occurred. Therefore, since the surface state was rejected, the evaluation of the cross-sectional state could not be performed because it did not hold as a bonded plate. As a result, the overall evaluation was rejected.
本発明に係る厚さ０．５〜３．０ｍｍのアルミニウム板材を複数枚接合する方法によって、表面の平滑性に優れ、かつ、欠陥のない大型の接合板が安価に提供可能となる。 By the method of joining a plurality of aluminum plate materials having a thickness of 0.5 to 3.0 mm according to the present invention, a large joining plate having excellent surface smoothness and having no defects can be provided at low cost.
１ アルミニウム板材
２ 溶接部の表面
３ 溶接部の断面
４ 溶接部の表面におけるピット状の欠陥
５ 溶接部の断面における気泡状の欠陥
DESCRIPTION OF
本発明は、板厚０．５〜３．０ｍｍのアルミニウム板材を同厚の組合せで複数枚溶接し、表面の平滑性に優れ、かつ、欠陥のない同厚の接合板を安価に提供する接合方法に関する。 The present invention welds a plurality of aluminum plate materials having a thickness of 0.5 to 3.0 mm in a combination of the same thickness , and provides a joint plate having the same thickness with excellent surface smoothness and no defects at low cost. Regarding the method.
本発明は上記従来技術の問題点を解決するためになされたものであり、厚さ０．５〜３．０ｍｍを有する複数枚の同厚のアルミニウム板材を、直流正極性ティグ溶接法にて溶接することにより、表面の平滑性に優れ、かつ、欠陥のない同厚の大型接合板を安価に製造する方法の提供を目的とする。 The present invention has been made to solve the above-mentioned problems of the prior art, and a plurality of aluminum plates having the same thickness of 0.5 to 3.0 mm are welded by a DC positive polarity TIG welding method. Accordingly, an object of the present invention is to provide a method for producing a large-sized bonded plate having the same thickness and excellent surface smoothness at low cost.
本発明は請求項１において、Ｍｇ：１．５ｍａｓｓ％以下を含有し残部Ａｌ及び不可避的不純物からなるＡｌ合金で構成され、厚さ０．５〜３．０ｍｍを有する複数枚の同厚のアルミニウム板材を、被溶接材として用意し、隣接するアルミニウム板材の端面同士を突合せてこの突合せ部を直流正極性ティグ溶接法によって溶接することにより平滑板を製造する方法において、タングステン電極と被溶接材であるアルミニウム板材との距離を１．０ｍｍ以下とし、純度７５〜１００％で流量５〜１５リットル／分のＨｅをシールドガスとして用い、溶加材を用いず、溶接時における単位板厚当たりの入熱量を２５００〜１００００（Ｊ／ｃｍ２）とすることを特徴とするアルミニウム板材の接合方法とした。
The present invention according to
本発明は請求項２では請求項１において、前記アルミニウム合金が、Ｓｉ：２．０ｍａｓｓ％以下、Ｆｅ：１．０ｍａｓｓ％以下、Ｃｕ：０．５ｍａｓｓ％以下及びＭｎ：２．０ｍａｓｓ％以下の１種又は２種以上を更に含有するものとした。 According to a second aspect of the present invention, in the first aspect, the aluminum alloy includes Si: 2.0 mass% or less, Fe: 1.0 mass% or less, Cu: 0.5 mass% or less, and Mn: 2.0 mass%. The following 1 type or 2 types or more were further contained.
本発明に係る溶接方法によって、厚さ０．５〜３．０ｍｍのアルミニウム板材を同厚で複数枚接合した、表面の平滑性に優れ、かつ、欠陥のない同厚の大型平滑板を安価に製造することができる。 By using the welding method according to the present invention , a plurality of aluminum plate materials having a thickness of 0.5 to 3.0 mm are joined to each other at the same thickness , and a large smooth plate having the same thickness with excellent surface smoothness and no defects is inexpensive. Can be manufactured.
本発明に係る厚さ０．５〜３．０ｍｍを有する複数枚の同厚のアルミニウム板材を接合する方法によって、表面の平滑性に優れ、かつ、欠陥のない同厚の大型の接合板が安価に提供可能となる。 Due to the method of joining a plurality of aluminum plates having the same thickness of 0.5 to 3.0 mm according to the present invention, a large joining plate having the same thickness with excellent surface smoothness and no defects is inexpensive. Can be provided.
Claims (3)
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| JP2010132519A JP2011255403A (en) | 2010-06-10 | 2010-06-10 | Method for joining aluminum plate material |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013056349A (en) * | 2011-09-07 | 2013-03-28 | Furukawa-Sky Aluminum Corp | Joining method of aluminum plate material |
| CN103111731A (en) * | 2013-01-23 | 2013-05-22 | 北京赛德高科铁道电气科技有限责任公司 | Welding method for longitudinal butt joint of thin-wall aluminum alloy non-profile long pipes |
| CN104475937A (en) * | 2014-11-27 | 2015-04-01 | 芜湖中集瑞江汽车有限公司 | 16-18mm plate thickness aluminum and aluminum alloy tungsten inert gas (TIG) welding process |
| CN104526127A (en) * | 2014-11-27 | 2015-04-22 | 芜湖中集瑞江汽车有限公司 | TIG (tungsten inert gas) welding process of aluminum with thickness exceeding 18mm and alloy thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01107971A (en) * | 1987-10-20 | 1989-04-25 | Sumitomo Light Metal Ind Ltd | Joining method for aluminum alloy shape |
| JPH03100144A (en) * | 1989-09-14 | 1991-04-25 | Sky Alum Co Ltd | Method for controlling color tone after anodic oxidation treatment of rolled aluminum alloy plate for building material |
| JPH0839285A (en) * | 1994-07-26 | 1996-02-13 | Sky Alum Co Ltd | Welding method of butt joint of aluminum sheet |
| JP2004202521A (en) * | 2002-12-24 | 2004-07-22 | Atsushi Niinuma | Welding method and welding equipment |
| JP2006263734A (en) * | 2005-03-22 | 2006-10-05 | Iwatani Industrial Gases Corp | High-quality gas shield arc welding equipment |
| JP2008207249A (en) * | 2008-03-24 | 2008-09-11 | Kobe Steel Ltd | Method for welding aluminum alloy material having excellent weld crack resistance, and method for evaluating weld crack resistance of aluminum alloy material |
-
2010
- 2010-06-10 JP JP2010132519A patent/JP2011255403A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01107971A (en) * | 1987-10-20 | 1989-04-25 | Sumitomo Light Metal Ind Ltd | Joining method for aluminum alloy shape |
| JPH03100144A (en) * | 1989-09-14 | 1991-04-25 | Sky Alum Co Ltd | Method for controlling color tone after anodic oxidation treatment of rolled aluminum alloy plate for building material |
| JPH0839285A (en) * | 1994-07-26 | 1996-02-13 | Sky Alum Co Ltd | Welding method of butt joint of aluminum sheet |
| JP2004202521A (en) * | 2002-12-24 | 2004-07-22 | Atsushi Niinuma | Welding method and welding equipment |
| JP2006263734A (en) * | 2005-03-22 | 2006-10-05 | Iwatani Industrial Gases Corp | High-quality gas shield arc welding equipment |
| JP2008207249A (en) * | 2008-03-24 | 2008-09-11 | Kobe Steel Ltd | Method for welding aluminum alloy material having excellent weld crack resistance, and method for evaluating weld crack resistance of aluminum alloy material |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013056349A (en) * | 2011-09-07 | 2013-03-28 | Furukawa-Sky Aluminum Corp | Joining method of aluminum plate material |
| CN103111731A (en) * | 2013-01-23 | 2013-05-22 | 北京赛德高科铁道电气科技有限责任公司 | Welding method for longitudinal butt joint of thin-wall aluminum alloy non-profile long pipes |
| CN104475937A (en) * | 2014-11-27 | 2015-04-01 | 芜湖中集瑞江汽车有限公司 | 16-18mm plate thickness aluminum and aluminum alloy tungsten inert gas (TIG) welding process |
| CN104526127A (en) * | 2014-11-27 | 2015-04-22 | 芜湖中集瑞江汽车有限公司 | TIG (tungsten inert gas) welding process of aluminum with thickness exceeding 18mm and alloy thereof |
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