مشخصات پژوهش

Pure copper and brass alloy with 30%wt Zn were successfully dissimilar joined using friction stir welding (FSW). The microstructure and mechanical properties of the copper and brass in the stir zone of the joint were characterized using light microscopy, electron backscattered diffraction (EBSD), transmission electron microscopy (TEM), and nanoindentation test. The results showed that both continuous and discontinuous dynamic recrystallizations (CDRX and DDRX) occurred during FSW. Higher values of DDRX in the brass caused (001)[110] shear texture with an intensity of 3.71, average grain size of 2.7 μm, 80% of high angle grain boundaries, Taylor factor of 3.01, and dense dislocation with tangle structures. On the other hand, (11̅2)[110] and (1̅12̅)[1̅1̅0] shear texture components with an intensity of 6.03, average grain size of 3.6 μm, 76% of high angle grain boundaries, Taylor factor of 2.99, and low density of dislocations with cell structures were formed in the copper due to the larger proportion of the CDRX. The lower n and higher σy values in brass (0.26/172.1 MPa) compared to those of the copper (0.37/76.2 MPa) were due to the higher amounts of strengthening mechanisms of grain boundaries and dislocations.