Abstract
Friction stir spot welding (FSSW) is a solid-state
welding process used for joining similar and dissimilar
materials. AA1060 and C11000 sheets were joined using
different process parameters and tool geometries. The presence
of a copper rings also called hooks were observed in all the
produced spot welds and their length increases with the tool
shoulder plunge depth; whereas the spot welds produced at
1200 rpm for the two tool geometries exhibited a decrease and
a slight increment in the length of the copper ring using a flat
pin/flat shoulder and conical pin/ concave shoulder,
respectively. Furthermore, the mapping of the produced spot
weld using energy dispersive spectroscopy (EDS) exhibited
different microstructures with the presence of copper
fragments and particles in the aluminium matrix. It was also
observed that, the shoulder plunge depth had an effect on the
shear tensile results, except for the weld produced at 800 rpm
when using a conical pin and a concave shoulder.