Work hardening of Ni-based single crystal alloy in vibration grinding based on molecular dynamics method

To study the work hardening of nickel-based superalloy during vibration-assisted grinding using cubic boron nitride (CBN) tool, a vibration-assisted grinding model of nickel-based superalloy was established by means of molecular dynamics (MD) simulation. Through in-depth analysis of dislocation proliferation and movement within the workpiece, the influence of internal obstacles on dislocation movement and the interaction between dislocations, we can understand the mechanism of work hardening. The effect of vibration grinding on the work hardening of nickel-based superalloys was studied by comparing the changes of external stress and dislocation density in the workpiece under vibration-assisted grinding and conventional grinding. The research shows that as the plastic deformation of the workpiece increases, the number and types of dislocations inside the workpiece also continue to increase, leading to a large amount of interaction between dislocations, resulting in the generation of obstacles such as dislocation jog, dislocation entanglement, and dislocation accumulation. These obstacles promote the occurrence of work hardening in the workpiece. The stress and dislocation density of nickel-based superalloy during vibration grinding are lower than that of conventional grinding, and the softening effect of vibration grinding significantly reduces the work hardening phenomenon of the workpiece.