Phase transformation at the interface during joining of an Al–Mg–Li alloy by pulsed current heating

Atom diffusion mechanisms at the interface during the joining of an Al–Mg–Li alloy by pulsed current heating were analyzed. Transmission electron microscopy results showed that the content of AlLi phase decreased with a symmetric distribution at the interface after joining. Moreover, Al4Li9 phase, which does not exist in the Al–Mg–Li alloy, was found growing around the AlLi phases at the interface. Current was found to be the main factor influencing the properties of joints formed by pulsed current heating.