Predicting the variation of stacking fault energy for binary Cu alloys by first-principles calculations

Abstract The variation of stacking fault energy (SFE) in a number of binary Cu alloys is predicted through considering the Suzuki segregation by the full potential linearly augmented plane wave (FPLAPW) method. The calculated results show that some solute atoms (Mg, Al, Si, Zn, Ga, Ge, Cd, Sn, and Pb), which prefer to form the Suzuki segregation, may decrease the value of SFE; while the others (Ti, Mn, Fe, Ni, Zr, Ag, and Au), which do not cause the Suzuki segregation may not decrease the SFE. Furthermore, it is interesting to find that the former alloying elements are located on the right of Cu group while the latter on the left of Cu group in the periodic table of elements. The intrinsic reasons for the new findings can be traced down to the valences electronic structure of solute and Cu atoms, i.e., the similarity of valence electronic structure between solute and Cu atoms increases the value of SFE, while the difference decreases the value of SFE.

**摘要**：通过考虑铃木偏聚，利用全势线性缀加平面波（FPLAPW）方法预测了多种二元铜合金中堆垛层错能（SFE）的变化。计算结果表明，一些倾向于形成铃木偏聚的溶质原子（镁、铝、硅、锌、镓、锗、镉、锡和铅）可能会降低堆垛层错能的值；而其他不引起铃木偏聚的溶质原子（钛、锰、铁、镍、锆、银和金）可能不会降低堆垛层错能。此外，有趣的是发现前一类合金元素在元素周期表中位于铜族右侧，而后一类位于铜族左侧。这些新发现的内在原因可归结于溶质原子和铜原子的价电子结构，即溶质原子与铜原子价电子结构的相似性会增加堆垛层错能的值，而两者的差异则会降低堆垛层错能的值。