Tensile Strength
Figure 2 shows the tensile stress and strain curves of the friction stir
processed FSWed joints. The AA6082/AA8011 joint recorded the maximum UTS
of 91.45 MPa with 22.28 % of percentage elongation whereas
AA8011/AA6082 joint recorded a maximum UTS of 85.1 MPa with a percentage
elongation of 20.22%. This therefore means that positioning of AA6082
on the advancing side resulted in better tensile properties in
comparison to AA8011 on the advancing side. However, the tensile
strength of the joints was found to be lower than the parent materials
(see Figure 2(b)). This is due to the tensile specimens failing on the
position of softer regions in which is mostly referred to as the weakest
point [26-29]. In the present case both specimens failed at the heat
affected zone (HAZ) on the side of AA8011 material. The positions of
fracture suggest that the FSPed joints were stronger compared to the
base material AA8011 and similar trend has been reported in the
literature [30-32].