A comparison between Sc and Cu segregation to Al (1 0 0)/Al3Li (1 0 0) interface

To evaluate the alloying effect on Al–Li alloy, we conduct a theoretical exploration to predict the behaviors of Sc and Cu segregation to Al/δ′ interface. The results show that Sc tends to segregation at Al3Li layer by substituting Li atom, while Cu prefers to replace Al atom of Al layer at the interface. The improvement of interface strength caused by segregated Sc and Cu is similar. The analysis of electronic properties of solute Sc and Cu atoms suggests that the difference of atomic radius and the electronegativity between them contribute to the discrepancy of segregation paths.