Improvement in tensile strength of Al/Cu dissimilar joints via submerged friction stir welding: revealing the action mechanism of water cooling on intermetallic compounds layer

In order to fabricate high-performance dissimilar joints of Al and Cu, it is critical to inhibit the growth of brittle intermetallic compounds (IMCs) at the interface. Therefore, submerged friction stir welding (SFSW) technology was used to join the Al/Cu dissimilar materials. The results revealed that the SFSW with water cooling significantly reduced the thickness of interfacial IMCs layer, and finer grains were formed at the Al side in nugget zone of SFSW joint compared to conventional friction stir welding (FSW). The mechanical properties of the joints produced by SFSW were improved. The tensile strength of the SFSW joint reached 221.5 MPa, which was 24.02% higher than that of the FSW joint. In addition, the SFSW could change the fracture position of joints, resulting in the fracture in the Al matrix.

Automated summary

In order to fabricate high-performance dissimilar joints of Al and Cu, it is critical to inhibit the growth of brittle intermetallic compounds (IMCs) at the interface. Therefore, submerged friction stir welding (SFSW) technology was used to join the Al/Cu dissimilar materials. The results revealed that the SFSW with water cooling significantly reduced the thickness of interfacial IMCs layer, and finer grains were formed at the Al side in nugget zone of SFSW joint compared to conventional friction stir welding (FSW). The mechanical properties of the joints produced by SFSW were improved. The tensile strength of the SFSW joint reached 221.5 MPa, which was 24.02% higher than that of the FSW joint. In addition, the SFSW could change the fracture position of joints, resulting in the fracture in the Al matrix.