An Interatomic Pair Potential for Aluminium Calculation of Stacking Fault Energy

A potential function for aluminium is derived from phonon dispersion curves. The contribution from short‐range multi‐ion interactions is substracted from the phonon data, and this affects markedly the short‐range characteristics of the potential. The potential function is used for the calculation of the energies of intrinsic and extrinsic stacking faults. Certain multi‐ion contributions to these energies are also evaluated. The calculation cannot explain the experimentally observed difference between γintr and γextr, which is attributed here to the interpretation of loop annealing observations in such faults. A re‐interpretation gives approximately 120 mJ/m2 for γintr and γextr.