Computational analysis for the microscopic mechanism of corrosion resistance of δ´ and δ precipitates

The quantitative research of the surface properties of δ ´ and δ precipitates is critical for exploring the microscopic mechanism of corrosion resistance of Al–Li alloys. Earlier calculation, however, fails to provide the accurate value of surface energy for non-stoichiometric surface of δ ´ and δ precipitates. Herein, we employed two different methods to predict the surface energy of non-stoichiometric δ ´ (100) surface and δ (100) stoichiometric surface quantitatively. Besides surface energy, the theoretical calculation of work function for δ ´ and δ (100) surface is well in agreement with the experimental result. Solute Zr is not only in favor of segregation to δ ´/Al interface, but also easily enters into the bulk interior of δ ´ precipitate by substituting Li atom, improving the corrosion resistance of Al–Li alloy due to its comparatively high electronegative.