Atomic Mechanisms and Mechanical Enhancement of Supersonic Fine Particle Bombarding‐Induced Microcrack Healing in γ‐TiAl

ABSTRACT Supersonic fine particle bombardment (SFPB) has been scarcely investigated in the damage repair of cracked substrates, and its microscale repair mechanism remains elusive. Based on molecular dynamics (MD) simulation, this study analyzes the crack healing process of single‐crystal γ‐TiAl alloy induced by SFPB, quantitatively investigating the correlation between crack healing degree and material strength with particle radius and crack angle as key variables. Findings demonstrate that crack healing is achieved through physical closure, with particle radius exerting a significant influence on healing efficacy. Cracks can disperse compressive stress, and this stress‐dispersing effect exhibits distinct angular dependence. SFPB is capable of enhancing the strength of cracked alloys and retarding crack propagation, with the matrix attaining its maximum strength when the crack is fully healed. This work provides theoretical guidance for the strengthening of cracked TiAl alloys via SFPB.