JP2006130514A - Electrode for spot welding - Google Patents

Electrode for spot welding Download PDF

Info

Publication number
JP2006130514A
JP2006130514A JP2004319434A JP2004319434A JP2006130514A JP 2006130514 A JP2006130514 A JP 2006130514A JP 2004319434 A JP2004319434 A JP 2004319434A JP 2004319434 A JP2004319434 A JP 2004319434A JP 2006130514 A JP2006130514 A JP 2006130514A
Authority
JP
Japan
Prior art keywords
electrode
nugget
welding
spot welding
diameter
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
Application number
JP2004319434A
Other languages
Japanese (ja)
Other versions
JP4521756B2 (en
Inventor
Tsutomu Azuma
努 東
Atsushi Kurobe
淳 黒部
Hiroshi Asada
博 朝田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Nisshin Co Ltd
Original Assignee
Nisshin Steel Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nisshin Steel Co Ltd filed Critical Nisshin Steel Co Ltd
Priority to JP2004319434A priority Critical patent/JP4521756B2/en
Publication of JP2006130514A publication Critical patent/JP2006130514A/en
Application granted granted Critical
Publication of JP4521756B2 publication Critical patent/JP4521756B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode for spot welding with which the welding can efficiently be performed without causing any donut-shaped nugget when a steel sheet having a relatively thin sheet thickness such as a high strength steel sheet is spot-welded. <P>SOLUTION: Regarding the electrode, the center of the abutting face in the tip abutted against the material to be welded is provided with a spherical recessed part having a diameter (ϕd) exceeding 1/2 of the diameter (ϕD) of the abutted face. Since the temperature in the central part of the abutted face in the electrode is made highest, the starting point of melting is formed at the axial core part in the electrode, and thereafter, it grows to the circumferential direction. As a result, a donut-shaped nugget is not formed, and satisfactory spot welding can be performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、板厚が比較的薄い鋼板をスポット溶接にする際に、ドーナツ状ナゲットの生成を抑制することが可能な形状を有するスポット溶接用電極に関する。   The present invention relates to a spot welding electrode having a shape capable of suppressing the formation of a doughnut-shaped nugget when spot welding is performed on a steel plate having a relatively thin plate thickness.

従来から、自動車や家電製品等の組立てラインにおいては、抵抗溶接法の中でも作業効率の高いスポット溶接法が多用されている。そして、大量生産ラインでは、連続的にスポット溶接が実施されている。このため、スポット溶接用の電極は、高熱，高負荷を繰り返し受ける状況下にあり変形しやすいので、その素材としては変形に耐え得るものでなければならない。しかも、抵抗溶接用電極の本来の必要条件である、高電気伝導度，高熱伝導性及び高強度，高耐摩耗性を備えていることが要求される。このような背景のもと、スポット溶接用電極Ｃｕ−Ｃｒ、Ｃｕ−Ｃｒ−Ｚｒ等の銅合金や、Ａｌ2Ｏ3等の硬質物質を分散させた銅材が用いられている。熱伝導特性や強度、コスト等の総合的な観点から、Ｃｕ−Ｃｒ合金が用いられる場合が多い。
そして、形状的には、先端に湾曲面を形成したＲ型，ＤＲ型や、先端を平坦にしたＣＦ型等に加工され、使用されている。 2. Description of the Related Art Conventionally, spot welding methods with high work efficiency are frequently used among resistance welding methods in assembly lines for automobiles, home appliances, and the like. In a mass production line, spot welding is continuously performed. For this reason, the electrode for spot welding is in a state where it is repeatedly subjected to high heat and high load and is easily deformed, so that the material must be able to withstand the deformation. Moreover, it is required to have high electrical conductivity, high thermal conductivity, high strength, and high wear resistance, which are the essential requirements for resistance welding electrodes. Against this background, copper alloys such as spot welding electrodes Cu—Cr and Cu—Cr—Zr, and hard materials such as Al 2 O 3 are used. Cu-Cr alloys are often used from a comprehensive viewpoint such as heat conduction characteristics, strength, and cost.
In terms of shape, they are processed and used as R type or DR type having a curved surface at the tip, or CF type having a flat tip.

また一方で、耐久性向上と軽量化を図るために自動車や家電製品等の素材として、板厚が比較的薄い高強度のめっき鋼板が多く使用されるようになっている。このような高強度めっき鋼板をスポット溶接する際には、普通鋼板をスポット溶接する際と比較して、大電流を流すことになる。殊に、高強度鋼板等の板厚が薄い鋼板は、板厚の厚い鋼板を溶接する場合と比較して電極からの冷却効果を大きく受けることからナゲットの成長が抑えられ、ナゲットの形状も図４（ａ）に示したような通常の楕円形に形成されるのではなく、図４（ｂ）に示したような外周部のみにナゲットが形成される、いわゆるドーナツ状ナゲットになることが多い。   On the other hand, in order to improve durability and reduce weight, high strength plated steel sheets having a relatively thin plate thickness are often used as materials for automobiles and home appliances. When spot-welding such a high-strength plated steel sheet, a larger current flows than when spot-welding a normal steel sheet. In particular, thin steel plates such as high-strength steel plates are greatly affected by the cooling effect from the electrodes compared to welding thick steel plates, so that the growth of the nugget is suppressed, and the nugget shape is also reduced. Instead of being formed into a normal oval shape as shown in FIG. 4 (a), it is often a so-called donut-shaped nugget in which a nugget is formed only at the outer periphery as shown in FIG. 4 (b). .

このため、自動車等、高い接合強度を必要とする分野では、基準ナゲット径を確保し難いために品質不良となる場合が多く、このドーナツ状ナゲットの生成を防止するためにチリ発生以上の高い溶接電流値で溶接する方法が取られている。また、このようなドーナツ状ナゲットは、電極先端の中央部分のみが大きく摩耗した場合、つまり電極寿命に達した電極で抵抗スポット溶接を実施した場合でも発生することがあるので、特許文献１で、抵抗スポット溶接の際の電極が材料に衝突するエネルギーを０．４Ｊ以上にすることが提案されている。
特開平４−３７１３７１号公報 For this reason, in fields that require high joint strength, such as automobiles, it is often the case that quality is poor because it is difficult to secure a standard nugget diameter. The method of welding with the current value is taken. In addition, such a doughnut-shaped nugget may occur even when only the central portion of the electrode tip is greatly worn, that is, when resistance spot welding is performed with an electrode that has reached the electrode life, in Patent Document 1, It has been proposed that the energy at which the electrode collides with the material during resistance spot welding is 0.4 J or more.
JP-A-4-371371

しかしながら、ドーナツ状ナゲットの発生を防止するために高い溶接電流で抵抗スポット溶接した場合、溶接部の板厚が極端に薄くなって溶接部の板厚基準を満足できなかったり、チリが発生するために作業環境が劣悪化したりするといった問題点がある。特許文献１で提案されたスポット溶接法では、電極からの冷却を制御することができないので、板厚が薄い高強度鋼板の溶接でドーナツ状ナゲットの発生を抑えることができない。
本発明は、このような問題を解消すべく案出されたものであり、高強度鋼板等、板厚が比較的薄い鋼板をスポット溶接にする際に、ドーナツ状ナゲットを発生させることなく、効率良く溶接可能なスポット溶接用電極を提供することを目的とする。 However, when resistance spot welding is performed at a high welding current to prevent the occurrence of a doughnut-shaped nugget, the thickness of the welded portion becomes extremely thin and the thickness standard of the welded portion cannot be satisfied, or dust is generated. However, there is a problem that the working environment deteriorates. In the spot welding method proposed in Patent Document 1, the cooling from the electrodes cannot be controlled, so that the occurrence of a doughnut-shaped nugget cannot be suppressed by welding a high-strength steel sheet having a small thickness.
The present invention has been devised to solve such a problem, and when spot-welding a steel sheet having a relatively small thickness, such as a high-strength steel sheet, without generating a donut-like nugget, the efficiency is improved. An object of the present invention is to provide a spot welding electrode that can be welded well.

本発明のスポット溶接用電極は、その目的を達成するため、被溶接材料に当接する電極先端の当接面中央に、該当接面の径の１／２を超える径を有する球状凹部を設けたことを特徴とする。
球状凹部の深さは、被溶接材の厚さよりも浅くすることが好ましい。 In order to achieve the object of the electrode for spot welding of the present invention, a spherical recess having a diameter exceeding 1/2 of the diameter of the corresponding contact surface is provided in the center of the contact surface of the electrode tip that contacts the material to be welded. It is characterized by that.
The depth of the spherical recess is preferably shallower than the thickness of the workpiece.

本発明においては、被溶接材料に当接する電極先端の当接面中央に球状凹部を設けたために、形成されるナゲットがドーナツ状になることなく良好なものが得られ、所望の溶接強度を達成できるスポット溶接を、効率良く行うことが可能になる。
電極先端形状がＲ型やＤＲ型の湾曲形状であれ、ＣＦ型の平坦形状であれ、単純な球状凹部を設けることにより、安定したナゲットの形成が可能となって、溶接部の肉厚減少を抑え、結果的に、板厚の薄い鋼板を生産性良くスポット溶接することができる。 In the present invention, since a spherical recess is provided in the center of the contact surface of the electrode tip that contacts the material to be welded, a good nugget is obtained without a donut shape, and a desired welding strength is achieved. Spot welding that can be performed can be performed efficiently.
Regardless of whether the electrode tip shape is a curved shape of R type or DR type, or a flat shape of CF type, the formation of a simple spherical recess enables stable nugget formation and reduces the thickness of the welded portion. As a result, a thin steel plate can be spot-welded with high productivity.

本発明者等は、比較的板厚の薄い鋼板をスポット溶接する際に、溶接不良であるドーナツ状ナゲットが形成される現象について検討を重ねてきた。
その結果、Ｒ型，ＤＲ型或いはＣＦ型等の通常の先端形状を有する電極を用いて、特に板厚の薄い高強度鋼板をスポット溶接する場合、上下電極の芯ずれや電極ロッドのたわみ、溶接機アームのたわみ等により、ナゲットが形成される起点となる位置は変動する。ナゲットの起点は溶接部中央に形成されるのではなく、溶接部中央より外れた位置に形成されやすい。ナゲットの成長はその起点部より楕円状に成長するため、溶接部中央より外れた位置に起点が形成されたナゲットは、成長してもその中心部に相当する部分に溶融部が形成されないドーナツ状ナゲットになることがあると推測した。 The inventors of the present invention have repeatedly studied a phenomenon in which a doughnut-shaped nugget that is poorly welded is formed when spot-welding a relatively thin steel plate.
As a result, when spot-welding thin high-strength steel sheets, especially with thin electrodes, such as R-type, DR-type, or CF-type electrodes, center displacement of upper and lower electrodes, deflection of electrode rods, welding The position at which the nugget is formed varies depending on the deflection of the machine arm. The starting point of the nugget is not formed at the center of the welded portion, but is easily formed at a position deviated from the center of the welded portion. Since the nugget grows in an elliptical shape from the starting point, the nugget where the starting point is formed at a position deviated from the center of the weld does not form a melted part in the portion corresponding to the central part even if it grows. I guess it might be a nugget.

また、鋼板を形状が対称な上下電極によりスポット溶接を行った場合、上下鋼板が接する板間部では鋼板自体の発熱による加熱とほぼ同時に電極から放射状に冷却作用を受ける。この際、通電により発生する発熱量は通電経路の範囲内で均一に発生するが、電極から受ける冷却量の大きさは電極からの距離により変化する。そして、板厚が薄い鋼板では電極からの冷却作用が大きいためにナゲットは成長し難い。このため、通常のＲ型，ＤＲ型或いはＣＦ型の電極を用いて板厚が薄い鋼板をスポット溶接した場合、溶接部中央から外れた位置に起点が形成された初期ナゲットは溶接部中央方向へ成長し難くなってドーナツ状ナゲットが発生しやすくなると考えられる。   In addition, when spot welding is performed on the steel plate with the upper and lower electrodes having symmetrical shapes, the inter-plate portion where the upper and lower steel plates are in contact with each other receives a cooling action radially from the electrodes almost simultaneously with the heating by the heat generation of the steel plate itself. At this time, the amount of heat generated by energization is uniformly generated within the range of the energization path, but the amount of cooling received from the electrode varies depending on the distance from the electrode. And since the cooling effect from an electrode is large with a thin steel plate, the nugget is difficult to grow. For this reason, when a thin steel plate is spot-welded using a normal R-type, DR-type, or CF-type electrode, the initial nugget where the starting point is formed at a position deviated from the center of the weld is directed toward the center of the weld. It is thought that it becomes difficult to grow and a donut-shaped nugget is likely to occur.

上記ナゲット起点位置の変動、及び電極の冷却効果によるナゲット成長の阻害のいずれもドーナツ状ナゲットの発生原因となり得るが、特に板厚の薄い鋼板をスポット溶接する際には、後者、すなわち電極による冷却効果の影響が大きいと考えられる。また、ドーナツ状ナゲットの発生を抑制するために、溶接機アームのたわみをなくしたり、上下電極の芯ずれを解消させたりすることはコスト的にも嵩むことになる。
そこで、本発明者等は、板厚の薄い鋼板をスポット溶接する際のドーナツ状ナゲットの発生を防止するために、冷却効果の影響が少ない電極先端形状について検討し、本発明に到達したものである。 Any of the above nugget origin position fluctuations and inhibition of nugget growth due to the cooling effect of the electrodes can cause the generation of doughnut-shaped nuggets, but the latter, that is, cooling by the electrodes, particularly when spot-welding thin steel plates The effect is considered to be large. Moreover, in order to suppress the occurrence of the doughnut-shaped nugget, it is costly to eliminate the deflection of the welder arm or to eliminate the misalignment of the upper and lower electrodes.
Therefore, the present inventors have studied the electrode tip shape with little influence of the cooling effect in order to prevent the occurrence of a doughnut-shaped nugget when spot welding a thin steel plate, and have reached the present invention. is there.

ナゲットの形成態様を、板厚が薄い鋼板をスポット溶接する際の状況を示す図１に基づいて説明する。
図１（ａ）に示すようにＲ型電極の場合、上下電極のずれ等により初期のナゲットは図２（ａ）に見られるように溶接部の中央から外れた位置で形成される。また、溶接部中央付近の板厚が減少し、なおかつ材料の板厚が薄いために溶接部中央付近の冷却作用が最も大きくなる。このため、初期に形成されたナゲットは溶接部中央方向へ成長し難くなり、結果としてドーナツ状ナゲットが発生しやすい傾向となる。
また、図１（ｂ）に示すようなＣＦ型電極の場合では、溶接部全体の板厚が減少し、材料の板厚が薄いために電極冷却効果は溶接部全体で大きくなる。このため、初期のナゲットはいずれの場所でも形成される可能性があり、しかも形成されたナゲットは成長し難くなる。この場合、ナゲットの形成は不安定で、結果としてドーナツ状ナゲットが発生しやすくなる。 The nugget formation mode will be described with reference to FIG. 1 showing the situation when spot welding is performed on a steel plate having a small thickness.
In the case of the R-type electrode as shown in FIG. 1A, the initial nugget is formed at a position deviated from the center of the welded portion as shown in FIG. Further, the plate thickness near the center of the weld is reduced, and the thickness of the material is thin, so that the cooling action near the center of the weld is maximized. For this reason, the nugget formed at an early stage becomes difficult to grow toward the center of the weld, and as a result, a doughnut-shaped nugget tends to be generated.
Further, in the case of the CF type electrode as shown in FIG. 1B, the plate thickness of the entire welded portion is reduced, and the plate thickness of the material is thin, so that the electrode cooling effect is increased in the entire welded portion. For this reason, the initial nugget may be formed anywhere, and the formed nugget is difficult to grow. In this case, the nugget formation is unstable, and as a result, a donut-shaped nugget is likely to occur.

これに対して、図１（ｃ）のように被溶接材料に当接する電極先端の当接面中央に球状凹部を設けると、電極からの冷却効果を考慮しても、同図に示すように当接面の中心部の温度が最も高くなる。そのため、図２（ｃ）に見られるように電極軸芯部に溶融の起点が形成され、その後周方向に成長して行く。この結果、ドーナツ状ナゲットは形成されることなく良好なスポット溶接が行える。   On the other hand, when a spherical recess is provided in the center of the contact surface of the electrode tip that contacts the material to be welded as shown in FIG. 1C, the cooling effect from the electrode is taken into consideration as shown in FIG. The temperature at the center of the contact surface is the highest. Therefore, as shown in FIG. 2 (c), a melting starting point is formed in the electrode shaft core portion, and thereafter grows in the circumferential direction. As a result, good spot welding can be performed without forming a doughnut-shaped nugget.

次に実際のスポット溶接用電極の材質・構造、及びその製造方法について説明する。
電極材質としては、通常のＣｕ系材料が用いられる。純Ｃｕでも良いし、１質量％程度のＣｒを含有させたものや、さらにＺｒをも含有させたものでも良い。或いはＡｌ2Ｏ3等の硬質物質を分散させたＣｕ材を用いても良い。
また使用する電極は、図３の（ａ），（ｂ）に見られるような、市販されているＲ型，ＤＲ型，ＣＦ型の電極チップに切削加工を施したり、上記Ｃｕ材を鋳造或いは鍛造する際に先端部に球状凹型を形成したりしてもよい。いずれにしても先端部形状を図３（ｃ），（ｄ）に見られるような形状に整えればよい。 Next, the material and structure of the actual spot welding electrode and the manufacturing method thereof will be described.
A normal Cu-based material is used as the electrode material. It may be pure Cu, or may contain about 1% by mass of Cr, or may contain Zr. Alternatively, a Cu material in which a hard substance such as Al 2 O 3 is dispersed may be used.
In addition, as for the electrodes to be used, cutting is performed on commercially available R-type, DR-type, and CF-type electrode tips, such as those shown in FIGS. A spherical concave mold may be formed at the tip when forging. In any case, the tip shape may be adjusted to a shape as shown in FIGS.

球状凹型の凹部寸法は、その径（φｄ）を電極先端径（φＤ）の１／２を超える径とする必要がある。
電極先端に球状凹部を設けたことにより、ナゲットは凹部直下の板間中央部より形成されるが、凹部の径を大きくした方が板間での電極冷却がより広範囲で軽減され、その結果ナゲットの成長が促進されて安定したナゲット径を得ることができる。しかしながら、凹部の径（φｄ）を電極先端径（φＤ）の１／２以下にした場合、ナゲットは十分に成長できず規定のナゲット径を得ることが難しくなる。
また、球状凹部の深さは被溶接材の板厚よりも浅くする必要がある。この理由は、球状凹部の深さを深くした場合、この窪み部への材料流入が大きくなるために、溶接後にナゲット上に凸部が発生して外観を損なうおそれがあるためである。また、溶接中に電極凹部と被溶接材の接合面に隙間が生じるために通電経路が分断されて凹部への通電が行われ難くなり、その結果としてドーナツ状ナゲットの発生を促進するおそれがあるためである。 As for the concave size of the spherical concave mold, the diameter (φd) needs to be larger than ½ of the electrode tip diameter (φD).
By providing a spherical recess at the tip of the electrode, the nugget is formed from the central part between the plates directly under the recess. However, increasing the diameter of the recess reduces the electrode cooling between the plates more widely, resulting in a nugget. The growth of this can be promoted and a stable nugget diameter can be obtained. However, when the diameter of the recess (φd) is set to ½ or less of the electrode tip diameter (φD), the nugget cannot be sufficiently grown and it becomes difficult to obtain a specified nugget diameter.
Further, the depth of the spherical concave portion needs to be shallower than the thickness of the material to be welded. This is because, when the depth of the spherical concave portion is increased, the material inflow into the concave portion is increased, so that a convex portion may be generated on the nugget after welding and the appearance may be impaired. In addition, since a gap is formed between the electrode recess and the welded material during welding, the energization path is divided, making it difficult for the recess to be energized, and as a result, the generation of a doughnut-shaped nugget may be promoted. Because.

Ｚｎ−５５％Ａｌ合金めっきを片面当り６０ｇ／ｍ2で施した板厚０．４ｍｍの２枚のＺｎ−Ａｌめっき鋼板を、先端直径が６ｍｍ，全体直径が１６ｍｍの電極であって、先端形状を種々に変えた電極を上下に用い、スポット溶接を行った。
なお、電極には純Ｃｕの鍛造材を用いた。また、従来電極形状として、先端直径が６ｍｍのＤＲ型（φ６ＤＲ）と先端直径が６ｍｍのＣＦ型（φ６ＣＦ）を採用し（図３の（ａ），（ｂ）参照）、本発明電極形状として、先端直径が６ｍｍのＤＲ型の先端部全域にＲ４０の球状凹部を形成したもの（φ６凹型）と先端直径が６ｍｍのＣＦ型の先端中央部にＲ２０の球状凹部を直径３．２ｍｍにわたって形成したもの（φ６−φ３.２凹型）を採用した（図３の（ｃ），（ｄ）参照）。 Two 0.4 mm thick Zn-Al plated steel sheets plated with Zn-55% Al alloy at 60 g / m 2 per side are electrodes with a tip diameter of 6 mm and an overall diameter of 16 mm. Spot welding was performed using electrodes with various changes in the top and bottom.
A pure Cu forging material was used for the electrodes. Moreover, as the conventional electrode shape, a DR type (φ6DR) having a tip diameter of 6 mm and a CF type (φ6CF) having a tip diameter of 6 mm are employed (see FIGS. 3A and 3B), and the electrode shape of the present invention is adopted. An R40 spherical recess formed in the entire tip of the DR type with a tip diameter of 6 mm (φ6 concave) and a spherical recess of R20 with a diameter of 3.2 mm at the center of the tip of a CF type with a tip diameter of 6 mm. The one (φ6-φ3.2 concave type) was adopted (see (c) and (d) of FIG. 3).

そして、φ６ＤＲ電極とφ６凹型電極を用いた場合には、種々の溶接電流で加圧力１５０ｋｇｆを加えて通電１０サイクルで溶接した。また、φ６ＣＦ電極とφ６−φ３.２凹型電極を用いた場合にも、種々の溶接電流で加圧力１５０ｋｇｆを加えて通電１０サイクルでスポット溶接した。
いずれのスポット溶接したものにおいても、図４に示す測定基準で、すなわち、正常なナゲットが形成されたものでは全体の直径（図４（ａ））を、ドーナツ状ナゲットが形成されたものでは最小部の径（図４（ｂ））を測定し、ナゲット径とした。そして、ナゲット径が４√ｔ＝２．５３（ｔは板厚で０．４）を上回るものを良好な溶接部と評価した。
各電極形状によるドーナツ状ナゲットの発生状況結果を図５，６に示す。
なお、図５中、黒塗りしたプロットがドーナツ状ナゲットの発生を意味している。 When a φ6DR electrode and a φ6 concave electrode were used, welding was performed in 10 energization cycles by applying a pressing force of 150 kgf with various welding currents. Further, when a φ6CF electrode and a φ6-φ3.2 concave electrode were used, spot welding was performed with 10 cycles of energization by applying a pressing force of 150 kgf with various welding currents.
In any of the spot welded materials, the overall diameter (FIG. 4 (a)) is the minimum in the measurement standard shown in FIG. 4, that is, in the case where a normal nugget is formed, and the minimum in the case where a doughnut-shaped nugget is formed. The diameter of the part (FIG. 4B) was measured and used as the nugget diameter. A nugget diameter exceeding 4√t = 2.53 (t is 0.4 in thickness) was evaluated as a good weld.
The results of the state of occurrence of the doughnut-shaped nugget with each electrode shape are shown in FIGS.
In FIG. 5, black plots indicate the occurrence of donut-shaped nuggets.

図５に示す結果からもわかるように、通常のＤＲ型，ＣＦ型の電極形状でチリが発生する溶接電流値までスポット溶接をした場合には、いずれの条件でもドーナツ状ナゲットが発生している。
これに対して、図６に示す結果からわかるように、先端に球状凹部を形成した電極を用いた場合、いずれの条件においてもドーナツ状ナゲットは発生しておらず、得られたナゲット径も基準値を大きく上回っていた。
このように、いずれの電極形状においても電極先端部に球状凹部を設けることによりドーナツ状ナゲットの発生を防止することができる。そして、電極形状は使用目的に合わせてＲ型，ＤＲ型，ＣＦ型等を選択することができ、その先端部に所定サイズの球状凹部を形成すれば、初期の目的を達成できるスポット溶接が可能になる。 As can be seen from the results shown in FIG. 5, when spot welding is performed up to the welding current value at which dust is generated with the normal DR type and CF type electrode shapes, donut-shaped nuggets are generated under any conditions. .
On the other hand, as can be seen from the results shown in FIG. 6, when an electrode having a spherical recess formed at the tip is used, no donut-shaped nugget is generated under any condition, and the obtained nugget diameter is also a reference. It was far above the value.
Thus, in any electrode shape, the formation of a doughnut-shaped nugget can be prevented by providing a spherical recess at the electrode tip. And the electrode shape can be selected from R type, DR type, CF type, etc. according to the purpose of use, and spot welding that can achieve the initial purpose is possible by forming a spherical recess of a predetermined size at the tip become.

電極形状と板間での温度分布を説明する図、（ａ）がＲ型電極，（ｂ）がＣＦ型電極，（ｃ）が本発明の球状凹型電極The figure explaining electrode shape and temperature distribution between plates, (a) is an R-type electrode, (b) is a CF-type electrode, and (c) is a spherical concave electrode of the present invention. 各種電極を用いた際のナゲットの起点を説明する図、（ａ）がＲ型電極，（ｂ）がＣＦ型電極，（ｃ）が本発明の球状凹型電極The figure explaining the starting point of the nugget when using various electrodes, (a) is an R-type electrode, (b) is a CF-type electrode, and (c) is a spherical concave electrode of the present invention. 電極形状を説明する図、（ａ）がＲ型，ＤＲ型電極，（ｂ）がＣＦ型電極，（ｃ），（ｄ）が本発明の球状凹型電極The figure explaining electrode shape, (a) is R type, DR type electrode, (b) is CF type electrode, (c), (d) is the spherical concave electrode of this invention ナゲットの評価方法を説明する図，（ａ）が正常なナゲット，（ｂ）がドーナツ状ナゲットFigure explaining the nugget evaluation method, (a) normal nugget, (b) donut-shaped nugget Ｒ型電極，ＣＦ型電極を用いて溶接した際のチリが発生するまでの溶接電流とナゲット径の関係を示した実験結果Experimental results showing the relationship between welding current and nugget diameter until dust is generated when welding is performed using R-type and CF-type electrodes 球状凹型電極を用いて溶接した際のチリが発生するまでの溶接電流とナゲット径の関係を示した実験結果Experimental results showing the relationship between welding current and nugget diameter until dust is generated when welding using a spherical concave electrode

Claims (2)

被溶接材料に当接する電極先端の当接面中央に、該当接面の径の１／２を超える径を有する球状凹部を設けたことを特徴とするスポット溶接用電極。   A spot welding electrode characterized in that a spherical recess having a diameter exceeding 1/2 of the diameter of the corresponding contact surface is provided in the center of the contact surface of the electrode tip that contacts the material to be welded. 被溶接材の厚さよりも浅い球状凹部を設けた請求項１に記載のスポット溶接用電極。   The spot welding electrode according to claim 1, wherein a spherical concave portion shallower than a thickness of the workpiece is provided.
JP2004319434A 2004-11-02 2004-11-02 Spot welding electrode Expired - Fee Related JP4521756B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004319434A JP4521756B2 (en) 2004-11-02 2004-11-02 Spot welding electrode

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004319434A JP4521756B2 (en) 2004-11-02 2004-11-02 Spot welding electrode

Publications (2)

Publication Number Publication Date
JP2006130514A true JP2006130514A (en) 2006-05-25
JP4521756B2 JP4521756B2 (en) 2010-08-11

Family

ID=36724512

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004319434A Expired - Fee Related JP4521756B2 (en) 2004-11-02 2004-11-02 Spot welding electrode

Country Status (1)

Country Link
JP (1) JP4521756B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008055437A (en) * 2006-08-29 2008-03-13 Daihatsu Motor Co Ltd Method of series spot welding and joined body obtained by the same welding
JP2010131666A (en) * 2008-12-08 2010-06-17 Kanto Auto Works Ltd Electrode for spot welding
CN105451924A (en) * 2013-05-03 2016-03-30 麦格纳国际公司 Aluminum spot welding method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0446684A (en) * 1990-06-13 1992-02-17 Toyota Motor Corp Spot resistance welding electrode
JPH04339573A (en) * 1991-01-29 1992-11-26 Honda Motor Co Ltd Electrode for resistance welding and its forming method
JPH0966370A (en) * 1995-09-01 1997-03-11 Nissan Motor Co Ltd Electrode for resistance spot welding to aluminum material to be welded and resistance spot welding method
JPH11342477A (en) * 1998-06-01 1999-12-14 Mitsubishi Electric Corp Spot welding method
JP2003251468A (en) * 2002-03-05 2003-09-09 Honda Motor Co Ltd Spot welding method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0446684A (en) * 1990-06-13 1992-02-17 Toyota Motor Corp Spot resistance welding electrode
JPH04339573A (en) * 1991-01-29 1992-11-26 Honda Motor Co Ltd Electrode for resistance welding and its forming method
JPH0966370A (en) * 1995-09-01 1997-03-11 Nissan Motor Co Ltd Electrode for resistance spot welding to aluminum material to be welded and resistance spot welding method
JPH11342477A (en) * 1998-06-01 1999-12-14 Mitsubishi Electric Corp Spot welding method
JP2003251468A (en) * 2002-03-05 2003-09-09 Honda Motor Co Ltd Spot welding method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008055437A (en) * 2006-08-29 2008-03-13 Daihatsu Motor Co Ltd Method of series spot welding and joined body obtained by the same welding
JP2010131666A (en) * 2008-12-08 2010-06-17 Kanto Auto Works Ltd Electrode for spot welding
CN105451924A (en) * 2013-05-03 2016-03-30 麦格纳国际公司 Aluminum spot welding method
JP2016518992A (en) * 2013-05-03 2016-06-30 マグナ インターナショナル インコーポレイテッド Aluminum welding method
US10668555B2 (en) 2013-05-03 2020-06-02 Magna International Inc. Aluminum spot welding method

Also Published As

Publication number Publication date
JP4521756B2 (en) 2010-08-11

Similar Documents

Publication Publication Date Title
JP6041374B2 (en) Spot welding method for steel plates with different thickness
US8455786B2 (en) Electrode head of the plasma cutting machine
CN109848522B (en) Ultrasonic-assisted GTAW (gas tungsten arc welding) pulsed arc welding method for duplex stainless steel sheet
JP2017217674A (en) Contact tip for welding electric power supply and manufacturing method thereof
JP2010131666A (en) Electrode for spot welding
US3689731A (en) Resistance welding electrode
JP4521756B2 (en) Spot welding electrode
GB2068814A (en) Resistance welding of sheets
JP2023013804A (en) Joining device and joining method for friction stir joining and resistance welding
JP7082356B2 (en) Friction stir welding tool and friction stir welding method
JP2011031269A (en) Resistance welding apparatus, and electrode used therefor
JP5901014B2 (en) Resistance welding method for plated steel cylindrical member
JP2020078811A (en) Electrode for resistance spot welding, and method of manufacturing resistance spot-welded joint
JPS5927674B2 (en) Contact tip for consumable electrode type arc welding
US20050029234A1 (en) Resistance spot welding electrode
JP2004114146A (en) Press-fitting joining structure and method
JPH0446684A (en) Spot resistance welding electrode
US11247293B2 (en) Spot weldment
JP2515562B2 (en) Resistance welding electrode
JP2536200B2 (en) Method for joining metal sintered materials, metal sintered material-made pool and method for manufacturing
JPH044984A (en) Electrode for resistance welding and its manufacture
JP2011140290A (en) Pipe for fuel tank having ring projection and method for welding the same
JP2008036672A (en) Method for spot-welding zinc-based-alloy-plated steel plate
JPH06179082A (en) Double action type resistance spot welding electrodes
CN105014216B (en) A kind of method for improving super-elasticity beryllium-bronze MEMS technology initial stage contact condition

Legal Events

Date Code Title Description
RD04 Notification of resignation of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7424

Effective date: 20070313

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071024

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100122

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100129

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100330

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20100520

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: 20100520

R150 Certificate of patent or registration of utility model

Ref document number: 4521756

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130604

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140604

Year of fee payment: 4

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees