Alloying behavior of erbium in an Al–Cu–Mg alloy

The alloying behavior of rare earth erbium in an Al–Cu–Mg alloy was characterized by employing OM, SEM, EDS, XRD and TEM. The results suggested the erbium mainly segregated to the grain boundaries in a form of Al8Cu4Er phase during solidification, which was crushed up along with the grain boundaries after hot rolling. Moreover, Al3Er phase with the L12 structure was also observed in the Al–Cu–Mg–Er alloy in T351 condition. The dendritic structure of as-cast Al–Cu–Mg alloy was refined remarkably by erbium addition.