In this paper, the formation mechanism of \(1/6<11\overline{2 }]\) Shockley partial dislocation bow-outs in the γ phase of TiAl alloys was investigated during the warm shot peening (WSP). The movement of such partial dislocations was attributed to the formation of dislocation bow-outs, specifically triangular and trapezoidal ones. Each bow-out consisted of stacking faults (complete and incomplete) and a dislocation configuration (triangular or trapezoidal). Therefore, the formation energy of the bow-outs was obtained by calculating the energy summation of these stacking faults and dislocation configurations. By deducing and analyzing the formation energy, a critical bow-out angle was proposed to characterize the stability of the dislocation bowing. During the Shockley partial dislocation bowing process, the lattice changes in front of the stacking fault were revealed. The complex trajectories of Ti and Al atoms during these lattice changes were attributed to the coupling of lattice distortion and shear under the impact of shots.
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