Molecular Dynamics Simulation of Single Crystal Ni₃Al Alloy During Laser Shock Peening

Excellent mechanical properties of nickel-based single crystal superalloy are mainly attributed to its ordered L1(2) structure of gamma' (Ni3Al) phase. In order to study the effect of laser shock on the microstructure evolution of gamma' phase, the molecular dynamics model of single crystal Ni3Al was constructed by molecular dynamics method, and the microstructure evolution behavior along [100], [110] and [111] crystal directions was analyzed. The results show that the plastic deformation mechanism of [100] crystal shock is the transformation from fcc phase to bcc phase, and the content of bcc phase is increased with increasing the shock pressure. The plastic deformation mechanism of [110] and [111] crystal direction shock is dislocation slip, and the [110] crystal direction slip system is mainly (1 (1) over bar(1) over bar)[011] and (1 (1) over bar1)[0 (1) over bar1]. The [111] crystal slip system is mainly (1 (1) over bar (1) over bar)[10 (1) over bar] and (1 (1) over bar1)[101], and the produced dislocations are mainly 1/6< 112> ( Shockley). However, with increasing the impact pressure, the plastic deformation mechanism is the transformation from fcc phase to bcc phase, and the disordered structure is produced at the same time.