Factors controlling segregation tendency of solute Ti, Ag and Ta into different symmetrical tilt grain boundaries of tungsten: First-principles and experimental study

In previous reports, experimental studies have shown that both thermal stability and strength can be controlled by grain boundary (GB) segregation. this study, we investigate the segregation behavior of solute (Ti, Ag Ta) atoms to low/high-angle symmetric tilt boundaries (STGBs) W using density functional theory (DFT) calculations supported TEM experiments. We found no preference for Ti or Ta at low-angle STGBs; however, they exhibit a slight tendency core high-angle STGBs. contrast, is more prone segregate in all around GB plane. estimated mechanical electronic contributions solution energy contribution dominant. Furthermore, role d?valence electrons atoms, was analyzed local states (PDOS). substantial hybridization case plays an important stabilizing W-Ta bonds, while anisotropic nature W-Ti bond contributes stabilize surrounding atoms. Charge transfer analysis revealed lose Contrary electronegativity rule, gain charge from neighboring excellent s?s may explain increased