: pp. 34-38
Technical University, Ilmenau, Germany
Technical University of Ilmenau, Germany
Technical University, Ilmenau, Germany
Technical University, Ilmenau, Germany
Technical University, Ilmenau, Germany
Technical University, Ilmenau, Germany
Technical University, Ilmenau, Germany

The exact determination of the process zone temperature can be considered as an increasingly important role in the control and monitoring of the friction stir welding process (FSW). At present, temperature measurement is carried out with the aid of a temperature sensor integrated into the tool (usually thermocouples). Since these cannot be attached directly to the joining area, heat dissipation within the tool and to the environment cause measurement deviations as well as a time delay in the temperature measurement. The article describes a process and the challenges that arise in this process, how a direct temperature measurement during the process can be achieved by exploiting the thermoelectric effect between tool and workpiece, without changing the tool by introducing additional temperature sensors.

[1] D. Schmid: Reibrührschweißen von Aluminiumlegierungen mit Stählen für die Automobilindustrie, Dissertation, TU München, Herbert Utz Verlag GmbH, 2015.
[2] A. Fehrenbacher, C. Smith, N. Duffie, N. Ferrier, F. Pferfferkorn, M. Zinn: Combined Temperature and Force Control for Robotic Friction Stir Welding, ASME, J. Manuf. Sci. Eng 136(2), 021007 (Jan 15, 2014), Paper No: MANU-12-1357;
[3] A.C.F. Silva, J. De Backer, G. Bolmsjö: Temperature measurements during friction stir welding, University West, Trollhättan, Sweden,, 2016.
[4] E. Cole, A. Fehrenbacher, N. Duffie, M. Zinn, F. Pfefferkorn, N. Ferrier: Weld temperature effects during friction stir welding of dissimilar aluminum alloys 6061-t6 and 7075-t6, Int J Adv Manuf Technol (2014) 71:643-652.
[5] A. Fehrenbacher, N. Duffie, N. Ferrier, F. Pfefferkorn, M. Zinn: Effects of tool-workpiece interface temperature on weld quality and quality improvements through temperature control in friction stir welding, The Int. Journ. Adv. Manuf. Techn., vol. 71, pp. 165-179, 2014/03/01, 2014.
[6] F. Bernhard (Hrsg.): Handbuch der Technischen Temperaturmessung, 2. Auflage, Springer-Verlag, 2014.
[7] M. Javurek, A. Mittermair: Wo in einem Thermoelement herrscht die gemessene Temperatur? Analyse mittels FE-Simulation, Technisches Messen, Heft 11, 2016, De Gruyter Oldenbourg.
[8] P. Germanow: Messtechnische Untersuchung der Kennlinienstabilität von Thermoelementen, TU Ilmenau, Masterarbeit, 2019.
[9] E.S. Webster: Low-Temperature Drift in MIMS Base-MetalThermocouples, Springer Verlag, Int J Thermophys (2014) 35:574-595.
[10] A.D. Greenen, E.S. Webster: Thermal Recovery from Cold-Working in Type K Bare-Wire Thermocouples, Springer Verlag, Int J Thermophys (2017) 38:179.
[11] M. Baranowski, K. Schmidt, M.K. Stobrawa: Anwendung des Seebeck-Effekts zur Messung der Prozesszonentemperatur beim Reibrührschweißen, Dokumentation Projektseminar, TU Ilmenau, 2018.
[12] M. Z. H. Khandkar, J. A. Khan, A. P. Reynolds: Prediction of temperature distribution and thermal history during friction stir welding: input torque based model, Sc. and Techn. of Welding & Joining, 8(3):165-174, 2003.