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Metal Science and Heat Treatment

, Volume 61, Issue 5–6, pp 379–386 | Cite as

Microstructure and Fracturing Behavior of AA7075–T651 Aluminum Alloy Cooled During Friction Stir Welding

  • T. Srinivasa RaoEmail author
  • S. R. Koteswara Rao
  • G. Madhusudhan Reddy
Article
  • 49 Downloads

Friction-stir-welded joints of 16-mm-thick plates of AA7075 aluminum alloy have been studied. The macrostructure of the weld region over the thickness of the plates and microstructures of various regions of the welded joint were determined using optical and transmission electron microscopes. Tensile testing of the welded samples was conducted, and the average values of the ultimate strength and yield point, as well as relative elongation were calculated. The Vickers hardness profiles in the middle of the cross-section of the welded joint were measured. Friction stir welding with forced cooling (by a compressed air flow or water immersion) was tested to reduce heat damage and improve mechanical properties. The efficiency of such welding has been demonstrated.

Key words

AA7075 aluminum alloy friction stir welding forced cooling fracturing transmission electron microscopy 

Notes

The authors acknowledge the financial support from the Armament Research Board, DRDO, Ministry of Defence, India, through an R&D project No. ARMREB/MAA/2012/142. The authors acknowledge the support provided by the DMRL, Hyderabad, for conducting friction stir welding trails. The authors would like to thank Dr. M. Selvaraj, Associate Professor, SSN College of Engineering, Chennai, for his help in computing the thermal cycles.

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • T. Srinivasa Rao
    • 1
    Email author
  • S. R. Koteswara Rao
    • 2
  • G. Madhusudhan Reddy
    • 3
  1. 1.Department of Mechanical Engineering, KKR and KSR Institute of Technology and SciencesGunturIndia
  2. 2.Department of Mechanical Engineering, SSN College EngineeringKalavakkamIndia
  3. 3.Metal Joining Group, Defense Metallurgical Research LaboratoryHyderabadIndia

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