Abstract
The new process of 'stationary shoulder' friction stir welding (SSFSW) has been directly compared to conventional (friction stir welding) using welds produced in a high strength AA7050-T7651 aluminium aerospace alloy. The process window for each approach was first compared using torque-rotation rate decay curves. Under optimum process conditions, SSFSW had a ∼30% lower heat input than FSW and the stationary shoulder resulted in narrower welds with a reduced heat affected zone (HAZ) width. The SSFSW welds also had more uniform through thickness properties and performed better than conventional FSWs in cross-weld tensile tests. In addition it is demonstrated that the SSFSW process resulted in a far superior surface finish, although the stationary shoulder led to surface 'speed cracking' under certain welding conditions. The reasons for these benefits are discussed aided by thermal and hardness modelling.
Original language | English |
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Pages (from-to) | 187-196 |
Number of pages | 10 |
Journal | Journal of Materials Processing Technology |
Volume | 221 |
DOIs | |
Publication status | Published - Jul 2015 |
Bibliographical note
Funding Information:We are grateful for Dr. J.D. Robson for assistance with the modelling work and financial support provided by EPSRC through LATEST2 , ( EP/G022402/1 ) and the Metallic Systems CDT ( EP/G036950/1 ).
Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.
Keywords
- AA7050
- Aluminium
- Friction stir welding
- Stationary shoulder
- Thermal modelling
ASJC Scopus subject areas
- Ceramics and Composites
- Computer Science Applications
- Metals and Alloys
- Industrial and Manufacturing Engineering