Electronic origin of solid solution softening in bcc molybdenum alloys.

摘要: The intrinsic mechanism of solid solution softening in bcc molybdenum alloys due to 5$d$ transition metal additions is investigated on the basis ab initio electronic-structure calculations that model effect alloying elements generalized stacking fault (GSF) energies. We demonstrate with an excess electrons (Re, Os, Ir, and Pt) lead a decrease GSF energy those lack (Hf Ta) its sharp increase. Using Peierls-Nabarro for nonplanar core, we associate local reduction enhancement double kink nucleation increase dislocation mobility, reveal electronic reasons observed dependence atomic number addition.