Solute atom segregation to I1 stacking fault and its bounding partial dislocations in a Mg–Bi alloy

Abstract

Stacking faults (SFs) and the interaction between solute atoms and SFs in a Mg–Bi alloy are investigated using aberration-corrected scanning transmission electron microscopy. It is found that abundant I₁ SFs are generated after cold rolling and are mainly distributed inside {10$\overline{1}$2} twins. After aging treatment, the formation of single-layer and three-layer Bi atom segregation in the vicinity of I₁ fault are clearly observed. Bi segregation also occurs at the 1/6<2$\overline{2}$03> bounding Frank partial dislocation cores. The segregation behaviors in I₁ fault and Frank dislocations are discussed and rationalized using first-principles calculations.