Texture evolution in AA6082-T6 BFSW welds: Optical microscopy and EBSD characterisation (2019)

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Journal ArticlePublisher
MDPI AGISSN
1996-1944Language
engCollections
Abstract
© 2019 by the authors. One of the difficulties with bobbin friction stir welding (BFSW) has been the visualisation of microstructure, particularly grain boundaries, and this is especially problematic for materials with fine grain structure, such as AA6082-T6 aluminium as here. Welds of this material were examined using optical microscopy (OM) and electron backscatter diffraction (EBSD). Results show that the grain structures that form depend on a complex set of factors. The motion of the pin and shoulder features transports material around the weld, which induces shear. The shear deformation around the pin is non-uniform with a thermal and strain gradient across the weld, and hence the dynamic recrystallisation (DRX) processes are also variable, giving a range of observed polycrystalline and grain boundary structures. Partial DRX was observed at both hourglass boundaries, and full DRX at mid-stirring zone. The grain boundary mapping showed the formation of low-angle grain boundaries (LAGBs) at regions of high shear as a consequence of thermomechanical nature of the process.
Citation
Tamadon A, Pons DJ, Clucas D, Sued K (2019). Texture evolution in AA6082-T6 BFSW welds: Optical microscopy and EBSD characterisation. Materials. 12(19). 3215-3215.This citation is automatically generated and may be unreliable. Use as a guide only.
Keywords
AA6082-T6; bobbin friction stir welding; microstructure; optical microscopy; EBSDANZSRC Fields of Research
40 - Engineering::4016 - Materials engineering::401607 - Metals and alloy materials34 - Chemical sciences::3403 - Macromolecular and materials chemistry::340307 - Structure and dynamics of materials
40 - Engineering::4017 - Mechanical engineering::401707 - Solid mechanics
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