A PRELIMINARY INVESTIGATION ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF DISSIMILAR Al TO Cu FRICTION STIR WELDS PREPARED USING SILVER INTERLAYER

• Shailesh Pandya

  English

  Author

• Jyoti Menghani

  English

  Author

Due to its solid-state nature, friction stir welding (FSW) process can be considered a better alternative for
dissimilar welding metals. However, like fusion welding techniques, in friction stir welding growth of thick
layers of brittle intermetallics - Cu9Al4 and CuAl2 is a significant issue. One solution to this problem is the use
of the suitable interlayer material. Use of interlayer material modifies the joint microstructure with the
replacement of thick, brittle intermetallics by more ductile intermetallics in a thin layer or particle form. The
present study is a preliminary investigation about joining of AA6082-O to pure copper joints with and without
silver (Ag) wire interlayer. Friction stir welded joints were characterized regarding optical microscopy, X-Ray
Diffraction (XRD) analysis, microhardness measurement, tensile testing and Scanning Electron Microscopy
(SEM) based fractography. The Al-Cu weld prepared using silver interlayer was stronger than without it. The
higher strength of the weld with silver interlayer is attributed to the formation of a composite type of structure
with intercalation of more ductile Ag2Al intermetallics along with dispersion of Ag particles in stir zone.

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