In this work, an attempt is made to understand the global and local tensile behaviour of AA2219 T87 Friction Stir Weld (FSW) utilizing a conventional mechanical extensometer and the Digital Image Correlation (DIC) technique. Laser shock peening (LSP) of tensile specimens was carried out on both sides (crown and root sides) and testing was done at ambient temperature. The global stress-strain behaviour by both methods is in agreement. In unpeened condition, the AA2219 FSW joint shows a yield strength of 218 MPa and an ultimate tensile strength of 366 MPa. LSP has increased the yield strength by 7 %, 11 % and 17 % with single, three, and six layers of peening, respectively. However, there is no significant change in UTS and elongation due to LSP. Further, region-wise strain fields were evaluated to obtain the local properties of the specimen. Weld nugget shows an increase of 7 %, 8 %, and 16 % in yield strength with single, three, and six layers of peening respectively, whereas Thermo Mechanically Affected Zone (TMAZ) in the advancing side shows an increase of 5 %, 10 %, and 21 % with single, three, and six layers of peening respectively. HAZ does not exhibit significant increase in yield strength. Microhardness increased by 1 %, 10 %, and 20 % due to single, three, and six layers of LSP, respectively, in the weld nugget. Single-layer peening has affected only surface level; however, three and six layers of peening have affected a depth of 1 mm and more than 2 mm, respectively, from the surface. The increase in hardness is due to plastic deformation induced by LSP. This study has brought out the improvement in yield strength of various zones of AA2219 FSW due to the LSP process, which is very crucial for the optimisation of the LSP process and improvement in structural margins of aerospace pressure vessels.
