DE4323149A1 - Electrode for resistance welding - Google Patents

Electrode for resistance welding

Info

Publication number
DE4323149A1
DE4323149A1 DE4323149A DE4323149A DE4323149A1 DE 4323149 A1 DE4323149 A1 DE 4323149A1 DE 4323149 A DE4323149 A DE 4323149A DE 4323149 A DE4323149 A DE 4323149A DE 4323149 A1 DE4323149 A1 DE 4323149A1
Authority
DE
Germany
Prior art keywords
electrode
welding
resistance welding
sheets
tib2
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.)
Withdrawn
Application number
DE4323149A
Other languages
German (de)
Inventor
Hans-Guenther Dip Haldenwanger
Peter Dr Ing Klose
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.)
Audi AG
Original Assignee
Audi AG
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 Audi AG filed Critical Audi AG
Priority to DE4323149A priority Critical patent/DE4323149A1/en
Publication of DE4323149A1 publication Critical patent/DE4323149A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/222—Non-consumable electrodes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K11/00—Resistance welding; Severing by resistance heating
    • B23K11/10—Spot welding; Stitch welding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2103/00—Materials to be soldered, welded or cut
    • B23K2103/08—Non-ferrous metals or alloys
    • B23K2103/10—Aluminium or alloys thereof

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Resistance Welding (AREA)

Abstract

A sheet metal resistance welding electrode according to the invention, in particular for the spot welding of aluminium sheets, consists essentially of an electrically highly conductive ceramic material, preferably titanium diboride (TiB2). In addition it may contain a proportion of 10%-25%, preferably 20%, of iron (Fe). Such an electrode, when employed in the resistance welding of aluminium sheets, can effectively prevent alloying and thus significantly improve electrode life.

Description

Die Erfindung betrifft eine Elektrode zum Widerstandsschweißen von Blechen, insbesondere zum Punktschweißen von Aluminiumblechen.The invention relates to an electrode for resistance welding of Sheets, especially for spot welding aluminum sheets.

Dem u. a. aus Umweltgesichtspunkten heraus resultierenden Zwang, den Treibstoffverbrauch von Kraftfahrzeugen zu reduzieren, läßt sich bei­ spielsweise durch eine gezielte Leichtbauweise der Fahrzeugkarosserien Rechnung tragen. Als ein hierfür besonders geeigneter Werkstoff hat sich Aluminium herauskristallisiert.The u. a. environmental constraint, the It is possible to reduce the fuel consumption of motor vehicles for example through a targeted lightweight construction of the vehicle bodies Take into account. As a particularly suitable material for this aluminum crystallizes out.

Aufgrund der gegenüber Stahlblech unterschiedlichen Werkstoffeigen­ schaften lassen sich die dort erprobten und ausgereiften Umform- und Fügetechniken nicht so ohne weiteres anwenden. Zwar kommen als Fügever­ fahren für Aluminiumblech grundsätzlich eine Reihe von Möglichkeiten in Betracht, nämlich Punktschweißen, Laserschweißen, Kleben, Nieten, Clin­ chen, wobei aber bei der Anwendung jedes der genannten Fügeverfahren neben zweifellos gegebenen Vorzügen auch beträchtliche Nachteile in Kauf zu nehmen sind.Due to the different material properties compared to sheet steel The tried and tested metal forming and Not so easy to use joining techniques. Although come as joining basically drive a number of options for aluminum sheet Consideration, namely spot welding, laser welding, gluing, riveting, clin chen, but when using each of the joining methods mentioned in addition to undoubted advantages, there are also considerable disadvantages in Purchase.

Gegen das beim Verarbeiten von Stahlblechen besonders gebräuchliche Punktschweißen spricht, daß beim Fügen von Aluminiumblechen die Stand­ zeit der Elektroden ausgesprochen gering ist. Bereits nach relativ wenigen gesetzten Schweißpunkten ist ein Auflegieren der Elektrodenkap­ pen zu beobachten, so daß diese ausgetauscht bzw. nachgearbeitet werden müssen.Against what is particularly common when processing steel sheets Spot welding speaks that when joining aluminum sheets the stand time of the electrodes is extremely short. Already after relative a few welding spots is an alloy of the electrode cap Observe pen so that they can be exchanged or reworked have to.

Unter "Auflegieren" versteht man dabei eine Legierungsbildung des Alu­ miniumwerkstoffes mit dem Kupfer der Schweißelektrode. "Alloying" means an alloying of the aluminum minium material with the copper of the welding electrode.  

Es wurde bereits frühzeitig über Maßnahmen nachgedacht, wie man durch geeignete Modifizierung der Elektrode Abhilfe schaffen kann. So schlägt beispielsweise die DE-PS 6 25 201 eine Elektrode mit mindestens einem schwerer und einem leichter schmelzenden Metall vor, bei der das schwe­ rer schmelzende Metall in das leichter schmelzende Metall eingebettet ist und im wesentlichen parallel zur Achse der Elektrode verläuft, wobei das schwerer schmelzende Metall, wie z. B. Wolfram, Molybdän, Tantal, die Form einer gewickelten Schicht, insbesondere Blech, hat, deren Faserrichtung ungefähr parallel zur Richtung des elektrischen Stromes liegt.Measures on how to get through were considered early on appropriate modification of the electrode can help. So beats for example DE-PS 6 25 201 an electrode with at least one heavier and a more easily melting metal in which the weld rer melting metal embedded in the easier melting metal and is essentially parallel to the axis of the electrode, the heavier melting metal, such as. B. tungsten, molybdenum, Tantalum, which is in the form of a wound layer, in particular sheet metal, whose fiber direction is roughly parallel to the direction of the electrical one Current is.

Dieser sowie auch weiteren, zwischenzeitlich getroffenen Maßnahmen war allerdings kein nachhaltiger Erfolg beschieden, um der Auflegierung vorbeugen und somit die Standzeit der Elektroden wesentlich verbessern zu können.This as well as other measures taken in the meantime was however, no sustained success has been granted to the alloy prevent and thus significantly improve the service life of the electrodes to be able to.

Der Erfindung liegt daher die Aufgabe zugrunde, eine Elektrode zum Widerstandsschweißen von Blechen, insbesondere von Aluminiumblechen, bereitzustellen, die eine wesentliche verbesserte Standzeit gewährlei­ stet.The invention is therefore based on the object of an electrode Resistance welding of sheets, in particular aluminum sheets, To provide a significantly improved service life continuous

Dies gelingt gemäß der Erfindung dadurch, daß die Elektrode im wesent­ lichen aus einem elektrisch hochleitfähigen Keramikwerkstoff, vorzugs­ weise Titandiborid (TiB₂), besteht.This is achieved according to the invention in that the electrode essentially Lichen from an electrically highly conductive ceramic material, preferably as titanium diboride (TiB₂).

Zwar ist es bekannt (DE 41 10 539 A1), Schweißelektroden zum Einsatz zu bringen, deren Grundwerkstoff Kupfer mit einer Titannitrid- oder Titan­ carbonnitrid-Verbindung beschichtet ist, eine Anregung für die erfin­ dungsgemäße Werkstoffwahl für eine Schweißelektrode ist diesem Stand der Technik allerdings nicht zu entnehmen.It is known (DE 41 10 539 A1) to use welding electrodes bring whose base material is copper with a titanium nitride or titanium carbon nitride compound is coated, a suggestion for the inventions The appropriate choice of material for a welding electrode is at this level not to be inferred from the technology.

Der erfindungsgemäß zum Einsatz kommende Werkstoff zeichnet sich durch eine hohe Druck-, Verschleiß-, Warmfestigkeit sowie durch eine günstige Formbeständigkeit aus. Ein Auflegieren findet praktisch nicht statt. The material used according to the invention is characterized by a high pressure, wear, heat resistance as well as a favorable Dimensional stability. There is practically no alloying.  

Seitens der Anmelderin durchgeführte Schweißversuche (AlMg5Mn-Bleche, Schweißparameter: Schweißstrom 5 bis 10 kA, Schweißspannung 10 V, Elektrodenanpreßkraft 2 bis 3 kN) brachten überraschenderweise beim Einsatz eine TiB₂-Elektrode sowohl hinsichtlich der Qualität der Füge­ verbindung als auch insbesondere im Hinblick auf die Standzeit der Elektrode einwandfreie Ergebnisse zutage. Positiv beeinflußt wird dies u. a. auch dadurch, daß die Elektrode aufgrund der werkstoffspezifi­ schen geringen Wärmeleitfähigkeit während des Schweißprozesses relativ warm wird, da die in der Schweißzone auftretende Wärme nicht so rasch abgeleitet werden kann. Auch trägt eine zusätzliche Vorwärmung, z. B. über einen heizbaren Elektrodenhalter, dazu bei, das Schweißergebnis weiter zu verbessern.Welding tests carried out by the applicant (AlMg5Mn sheets, Welding parameters: welding current 5 to 10 kA, welding voltage 10 V, Electrode contact force 2 to 3 kN) surprisingly brought Use a TiB₂ electrode both in terms of the quality of the joint connection and in particular with regard to the service life of the Electrode shows perfect results. This is positively influenced u. a. also in that the electrode due to the material-specific relatively low thermal conductivity during the welding process becomes warm because the heat that arises in the welding zone is not as rapid can be derived. Also carries additional preheating, e.g. B. via a heatable electrode holder, to ensure the welding result continue to improve.

Ist die Elektrode als reine TiB₂-Elektrode ausgeführt, so haben sich wegen der weiteren Eigenschaften (Sprödigkeit) des Keramikwerkstoffes und zur Reduzierung der Wärmeeigenspannungen eine relativ langsame Vorwärmung auf ca. 550°-600°C und möglichst nicht zu überschreitende Abmessungen, nämlich Elektroden-⌀ = 7 mm, Elektrodenlänge 1-12 mm, bewährt. Weist die Elektrode einen Anteil von 10%-25%, vorzugsweise 20%, Eisen (Fe) auf, so haben sich Vorwärmtemperaturen in der Größe­ nordnung von ca. 480°C bewährt, wobei die Vorwärmung selbst relativ rasch erfolgen kann. Die vorstehend genannten Abmessungsobergrenzen (⌀ = 7 mm, 1-12 mm) brauchen dann nicht eingehalten zu werden.If the electrode is designed as a pure TiB₂ electrode, then because of the other properties (brittleness) of the ceramic material and a relatively slow one to reduce the residual thermal stresses Preheating to approx. 550 ° -600 ° C and if possible not to be exceeded Dimensions, namely electrode ⌀ = 7 mm, electrode length 1-12 mm, proven. The electrode has a share of 10% -25%, preferably 20%, iron (Fe) on, so preheating temperatures have increased in size Proven of approximately 480 ° C, the preheating itself relative can be done quickly. The above-mentioned upper dimensions (⌀ = 7 mm, 1-12 mm) then do not need to be observed.

Die erfindungsgemäße Titandiborid-Elektrode kann ansonsten hinsichtlich ihrer Formgebung der einer gängigen Kupferelektrode entsprechen, als Wendeelektrode ausgeführt und von einem Elektrodenhalter in bekannter Weise aufgenommen sein, wobei dieser sie eng (unter Druckvorspannung) umschließen sollte, um dadurch ihre mechanische Belastbarkeit gegenüber den während des Schweißvorganges auftretenden Beanspruchungen zu erhöhen.The titanium diboride electrode according to the invention can otherwise in terms of their shape correspond to that of a common copper electrode, as Reversible electrode executed and known from an electrode holder Be recorded in a manner that is tight (under pressure) should enclose in order to thereby counteract their mechanical resilience the stresses that occur during the welding process increase.

Claims (4)

1. Elektrode zum Widerstandsschweißen von Blechen, insbesondere zum Punktschweißen von Aluminiumblechen, dadurch gekennzeichnet, daß die Elektrode im wesentlichen aus einem Keramikwerkstoff, vorzugsweise Titandiborid (TiB₂), besteht.1. Electrode for resistance welding of sheets, in particular for spot welding of aluminum sheets, characterized in that the electrode consists essentially of a ceramic material, preferably titanium diboride (TiB₂). 2. Elektrode nach Anspruch 1, dadurch gekennzeichnet, daß sie einen Anteil von 10%-25%, vorzugsweise 20%, Eisen (Fe) enthält.2. Electrode according to claim 1, characterized in that it has a Contains 10% -25%, preferably 20%, iron (Fe). 3. Elektrode nach Anspruch 1, dadurch gekennzeichnet, daß diese unter Druck-Vorspannung von einem Elektrodenhalter aufgenommen wird.3. Electrode according to claim 1, characterized in that this under Pressure bias is received by an electrode holder. 4. Elektrode nach Anspruch 1, dadurch gekennzeichnet, daß diese von einem heizbaren Elektrodenhalter aufgenommen wird4. Electrode according to claim 1, characterized in that this of a heatable electrode holder is accommodated
DE4323149A 1993-07-10 1993-07-10 Electrode for resistance welding Withdrawn DE4323149A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE4323149A DE4323149A1 (en) 1993-07-10 1993-07-10 Electrode for resistance welding

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Application Number Priority Date Filing Date Title
DE4323149A DE4323149A1 (en) 1993-07-10 1993-07-10 Electrode for resistance welding

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DE4323149A1 true DE4323149A1 (en) 1995-01-12

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DE (1) DE4323149A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19520514A1 (en) * 1995-06-03 1996-12-05 Bayerische Motoren Werke Ag Electrode for resistance spot welding of aluminum sheets
EP1452261A1 (en) * 2003-02-25 2004-09-01 Forschungszentrum Karlsruhe GmbH Heatable tooltip made of a ceramic
CN100349687C (en) * 2004-08-08 2007-11-21 湖北汽车工业学院 Coated stick of spot welding electrode surface electric spark coating layer and its preparing method
CN100445016C (en) * 2005-11-30 2008-12-24 陈铮 Copper alloy electrode for resistance weld and its manufacturing method
US20140013869A1 (en) * 2012-07-11 2014-01-16 Ford Global Technologies, Llc Resistance spot weld electrode dresser
CN103801851A (en) * 2013-12-16 2014-05-21 湖北工业大学 Deposition rod for electric spark deposition of Al2O3-TiB2 coating on surface of spot-welding electrode and manufacturing method thereof
CN103801858A (en) * 2013-12-16 2014-05-21 湖北工业大学 Deposition rod for electric spark deposition of TiB2-TiC multi-phase coating on surface of spot-welding electrode and manufacturing method thereof

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE625201C (en) * 1933-08-12 1936-02-06 Molybdenum Company Nv At least one heavy and at least one lighter melting metal containing electrode, especially for electrical resistance welding
DE2203776B2 (en) * 1972-01-27 1976-12-16 Battelle-Institut E.V., 6000 Frankfurt HEAVY-DUTY ELECTRICAL CONTACTS OR ELECTRODES AND METHOD FOR PRODUCING THEM
DE2710835B2 (en) * 1976-03-16 1980-09-04 International Business Machines Corp., Armonk, N.Y. (V.St.A.) Welding device for welding a thin wire to contact connections on a semiconductor substrate
DE3024079A1 (en) * 1980-06-26 1982-01-07 Siemens AG, 1000 Berlin und 8000 München Electrode for intermittent welding, esp. spot welding of aluminium - is made of material such as silver so that unsightly marks are not left on workpieces
SU1260155A1 (en) * 1985-06-11 1986-09-30 Ивано-Франковский Институт Нефти И Газа Material for nonconsumable electrode
US4617053A (en) * 1985-09-20 1986-10-14 Great Lakes Carbon Corporation Metal reinforced porous refractory hard metal bodies
EP0291277A1 (en) * 1987-05-13 1988-11-17 Alcan International Limited Resistance welding of aluminium
US4843206A (en) * 1987-09-22 1989-06-27 Toyota Jidosha Kabushiki Kaisha Resistance welding electrode chip
DE3844001A1 (en) * 1987-12-25 1989-07-06 Honda Motor Co Ltd ELECTRODES FOR USE IN SPOT WELDING
DE4110539A1 (en) * 1990-04-11 1991-10-17 Volkswagen Ag Titanium nitride or carbonitride coated copper component - used esp. in resistance or arc welding or in electrical switches
US5066845A (en) * 1989-09-11 1991-11-19 Alcotec Wire Company Resistance welding electrode coated with ceramic layer
DE4139157C2 (en) * 1990-11-30 1993-08-12 Murata Mfg. Co., Ltd., Nagaokakyo, Kyoto, Jp

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE625201C (en) * 1933-08-12 1936-02-06 Molybdenum Company Nv At least one heavy and at least one lighter melting metal containing electrode, especially for electrical resistance welding
DE2203776B2 (en) * 1972-01-27 1976-12-16 Battelle-Institut E.V., 6000 Frankfurt HEAVY-DUTY ELECTRICAL CONTACTS OR ELECTRODES AND METHOD FOR PRODUCING THEM
DE2710835B2 (en) * 1976-03-16 1980-09-04 International Business Machines Corp., Armonk, N.Y. (V.St.A.) Welding device for welding a thin wire to contact connections on a semiconductor substrate
DE3024079A1 (en) * 1980-06-26 1982-01-07 Siemens AG, 1000 Berlin und 8000 München Electrode for intermittent welding, esp. spot welding of aluminium - is made of material such as silver so that unsightly marks are not left on workpieces
SU1260155A1 (en) * 1985-06-11 1986-09-30 Ивано-Франковский Институт Нефти И Газа Material for nonconsumable electrode
US4617053A (en) * 1985-09-20 1986-10-14 Great Lakes Carbon Corporation Metal reinforced porous refractory hard metal bodies
EP0291277A1 (en) * 1987-05-13 1988-11-17 Alcan International Limited Resistance welding of aluminium
US4843206A (en) * 1987-09-22 1989-06-27 Toyota Jidosha Kabushiki Kaisha Resistance welding electrode chip
DE3844001A1 (en) * 1987-12-25 1989-07-06 Honda Motor Co Ltd ELECTRODES FOR USE IN SPOT WELDING
US5066845A (en) * 1989-09-11 1991-11-19 Alcotec Wire Company Resistance welding electrode coated with ceramic layer
DE4110539A1 (en) * 1990-04-11 1991-10-17 Volkswagen Ag Titanium nitride or carbonitride coated copper component - used esp. in resistance or arc welding or in electrical switches
DE4139157C2 (en) * 1990-11-30 1993-08-12 Murata Mfg. Co., Ltd., Nagaokakyo, Kyoto, Jp

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Derwent Abstracts: Nr.89-373719/51 zu JP 1278975A *
Nr.87-183142/26 zu JP 62114780A *
Nr.89-354197/48 zu JP 1276975A *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19520514A1 (en) * 1995-06-03 1996-12-05 Bayerische Motoren Werke Ag Electrode for resistance spot welding of aluminum sheets
EP1452261A1 (en) * 2003-02-25 2004-09-01 Forschungszentrum Karlsruhe GmbH Heatable tooltip made of a ceramic
DE10307832A1 (en) * 2003-02-25 2004-09-09 Forschungszentrum Karlsruhe Gmbh Tool in the form of a heated pin
DE10307832B4 (en) * 2003-02-25 2008-01-17 Forschungszentrum Karlsruhe Gmbh Tool in the form of a heatable pen
CN100349687C (en) * 2004-08-08 2007-11-21 湖北汽车工业学院 Coated stick of spot welding electrode surface electric spark coating layer and its preparing method
CN100445016C (en) * 2005-11-30 2008-12-24 陈铮 Copper alloy electrode for resistance weld and its manufacturing method
US20140013869A1 (en) * 2012-07-11 2014-01-16 Ford Global Technologies, Llc Resistance spot weld electrode dresser
US8920218B2 (en) * 2012-07-11 2014-12-30 Ford Global Technologies, Llc Resistance spot weld electrode dresser
CN103801851A (en) * 2013-12-16 2014-05-21 湖北工业大学 Deposition rod for electric spark deposition of Al2O3-TiB2 coating on surface of spot-welding electrode and manufacturing method thereof
CN103801858A (en) * 2013-12-16 2014-05-21 湖北工业大学 Deposition rod for electric spark deposition of TiB2-TiC multi-phase coating on surface of spot-welding electrode and manufacturing method thereof
CN103801851B (en) * 2013-12-16 2016-04-06 湖北工业大学 Spot-wedling electrode electric spark on surface deposition Al 2o 3-TiB 2deposition rod of coating and preparation method thereof
CN103801858B (en) * 2013-12-16 2016-06-08 湖北工业大学 Spot-wedling electrode electric spark on surface deposition TiB2The deposition rod of-TiC coating

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