Effect of pressure on stacking fault energy and deformation behavior of face-centered cubic metals

Abstract

Stacking fault energy (SFE) is a fundamental property affecting the nucleation and dissociation of the partial dislocations, which is also responsible for the twinning propensity of a material. Using density functional theory (DFT) based ab initio calculations, we study the pressure dependence of twinnability of 14 face-centered cubic (FCC) metals, including 7 transition and 3 noble metals. We find that although pressure alters the SFE values significantly, it does not affect the twinning propensity of FCC metals, barring few exceptions like Al, Pt and Au within a range of -10 GPa to +10 GPa hydrostatic pressure. In case of transition metals, we observe a correlation between the pressure dependence of SFE and width of the d-band, which confirms a direct connection between the electronic ground state and SFE.