Microstructure and Mechanical Properties of 2A14-T4 Alloy T-Joint Connected by Stationary Shoulder Friction Stir Welding

Evolution of Microstructures, Texture and Mechanical Properties of Al-Mg-Si-Cu Alloy under Different Welding Speeds during Friction Stir Welding

“…This is due to the good fluidity of the RS tissue and the combined effect of the compression of the RS tissue by the shaft shoulder and the shearing of the stirring pin, which causes the material in the upper part of the weld to be squeezed into the NZ [13]. The tissue in the NZ is subjected to the compression of the axial shoulder and the stirring action of the stirring needle, and the original tissue undergoes intense thermomechanical coupling, so the grains in the NZ undergo dynamic recrystallisation, producing fine isometric axial grains [14]. Figure 3(a2-d2) shows the grain size distribution map derived through Channel 5 software, while the average grain size of the weld nucleus zone was calculated for the different welding speeds of 3.898 µm, 3.692 µm, 2.945 µm and 3.2 µm.…”

“…Figure 3 shows the EBSD figure, grain size distribution figure and grain boundary orientation angle distribution figure for the NZ at different welding speeds. Figure 3(a1-d1) includes red (2 ~ 5°) thick lines and green (5 ~ 15°) thick lines on behalf of small angle grain boundaries, and black (15 ~ 65°) thick lines on behalf of large angle grain boundaries.The tissue in the NZ is subjected to the compression of the axial shoulder and the stirring action of the stirring needle, and the original tissue undergoes intense thermomechanical coupling, so the grains in the NZ undergo dynamic recrystallisation, producing fine isometric axial grains[14]. Figure3(a2-d2) shows the grain size distribution map derived through Channel 5 software, while the average grain size of the weld nucleus zone was calculated for the different welding speeds of 3.898 µm, 3.692 µm, 2.945 µm and 3.2 µm.…”