Comparative Study of Electrically Assisted Pressure Joining of Aluminum 6061-T6 Alloys and Copper C11000 Alloys

This study compares the electrically assisted pressure joining (EAPJ) performances of two non-ferrous alloys, aluminum (Al) 6061-T6 and copper (Cu) C11000. For joining, two cylindrical specimens with identical geometries are assembled in a longitudinal direction. Electric currents with various electric current densities are applied directly to the specimen assemblies during continuous axial plastic deformation. Microstructural analysis confirms that the joints are successfully fabricated without melting and solidification in both material combinations. While the mechanical properties of the joints are strongly affected by the electric current density, the results also show that both joining temperature and amount of plastic deformation for successful EAPJ of the C11000 alloy are much lower than those of the Al 6061-T6 alloy. In EAPJ, the Cu C11000 even can be joined at a temperature (250 °C) lower than the 0.3–0.7T_m range (T_m: the melting temperature of material), while the Al 6061-T6 requires the joining temperature (450 °C), which is about 0.7T_m for that material. The present study confirms that the process parameters for successful EAPJ can strongly differ depending on the metal alloy.