Cooling rate effect on temperature controlled FSW process
2015 (English)Conference paper, Presentation (Refereed)
A continuous trend towards more demanding jointgeometries is imposed across various manufacturingindustries. During Friction Stir Welding (FSW) of suchcomplex geometries, the surrounding environment playsan important role on the final weld quality, especially inthermal aspects. In order to guarantee a consistent weldquality for different conditions, in-process weldingparameter adaptation is needed.This paper studies the effect of the cooling rate onmechanical properties for temperature controlled FSW byusing different backing bar materials. A new temperaturesensor solution, the Tool-Workpiece Thermocouple(TWT) method , was applied to measure thetemperature during welding. A FSW-robot equipped withtemperature and force feedback control was used, whererotation speed was varied to maintain a constant weldingtemperature. AA7075-T6 lap joints were performed withand without temperature control. The cooling rate duringwelding was acquired and macrographs and mechanicalproperties were evaluated for each weld. The rotationspeed offered a fast response promoting the heat inputnecessary to weld at the set temperature. Temperaturecontrolled welds presented a better behaviour undertensile loads. The results prove that temperature controlusing the TWT method is suitable to achieve higher jointquality and provides a fast setup of optimal parameters fordifferent environments.The work presented is an important step in the processoptimization through feedback control which willconsider not only the operational parameters of theprocess as such but also the resulting quality of the joint.
Place, publisher, year, edition, pages
Helsinki, Finland, 2015. 1-5 p.
Friction Stir weld, Cooling rate, TWT method, Temperature control, Aluminium alloy
Manufacturing, Surface and Joining Technology
Research subject ENGINEERING, Manufacturing and materials engineering; Production Technology
IdentifiersURN: urn:nbn:se:hv:diva-9120OAI: oai:DiVA.org:hv-9120DiVA: diva2:906831
IIW International Conference High-Strength Materials - Challenges and Applications, 2-3 July 2015, Helsinki, Finland, Helsingfors, 2015