Influence of multipass high rotating speed friction stir processing on microstructure evolution, corrosion behavior and mechanical properties of stirred zone on AZ31 alloy

The mechanical properties of AA6082/AA1050 dissimilar joints subjected to multi-pass friction stir processing

“…However, the bonding improved with an increase in number of FSP passes hence the fracture occurred outside the stir zone towards the retreating side. It was further observed that 4P FSP specimens failed at the stir zone and this suggests that the joint lost its strengthening precipitates or phases due to high heat input occurring at higher multi-pass FSP [11][12][13][14][25][26][27]. The ultimate tensile strength (UTS) of specimens that were subjected to 1P FSP fluctuated between 71.9 MPa and 74.7 MPa whereas the UTS for specimens that were subjected to 2P FSP procedure fluctuated between 73.3 MPa and 79.3 MPa.…”

“…It has been reported that FSP technique plays a significant role in creating microstructure that contains fine grains with large grain boundary disorientations and high angle grain boundaries and these features are influential on mechanical behavior of metals [9,10]. The recent works have shown that FSP technique can be repeatedly employed on metal's surface and this is termed as multi-pass friction stir processing (MFSP) [11][12][13][14]. MFSP is a versatile technique that can be used to fabricate hybrid surface composites and also to enhance various properties of the welded joint [12][13][14][15][16][17][18][19].…”

“…The recent works have shown that FSP technique can be repeatedly employed on metal's surface and this is termed as multi-pass friction stir processing (MFSP) [11][12][13][14]. MFSP is a versatile technique that can be used to fabricate hybrid surface composites and also to enhance various properties of the welded joint [12][13][14][15][16][17][18][19]. This was demonstrated by Yadav et al [20] where' they investigated the influence of friction stir processing on the microstructure and the mechanical properties of aluminium alloy.…”

Friction Stir Welding/Processing of Mg-Based Alloys: A Critical Review on Advancements and Challenges

“…It was shown [25,[61][62][63] that the FSWed or FSPed material can acquire the capability of superplasticity because of the formation of a fine-grained or ultrafine-grained structure during FSW/FSP. Liu et al [64] demonstrated that FSP could lead to considerable grain refinement and microstructure uniformity in the SZ of the AZ31 alloy owing to complete DRX. Due to grain refinement and subgrain boundaries, FSP can enhance the mean microhardness of the SZ to some extent so that in this material, grain boundary sliding (GBS) becomes the dominant mechanism of plastic deformation at high temperatures and high strain rates during superplastic deformation [25,65,66].…”