Research on the mechanism of surface damage of Ni-based high-temperature alloy GH4169 based on nano-cutting

Abstract

In order to investigate how cutting parameters affect the nano-cutability of Ni-based high-temperature alloy GH4169, molecular dynamics (MD) simulations of the material have been conducted on a large-scale atomic molecular/massively parallel simulator (LAMMPS) for different cutting speeds and cutting depths. EAM potential is used between Ni, Fe and Cr, whereas Moses potential is used between the workpiece and the tool or between the tools. The results show that at the cutting depth of 1 nm, the chip shape has a tensile necking with increasing cutting speed; at the cutting depth of 3 nm, the shear line width increases with increasing cutting distance and there is an abrupt change in the evolution of both FCC and amorphous atoms at all cutting speeds. At the same cutting depth, the cutting area temperature increases with increasing cutting speed; at the same cutting speed, the cutting area temperature increases markedly with increasing cutting depth, too.The dislocation density of 1/6<112> Shockley with a cutting depth of 1 nm is higher than that of other depths at the same cutting speed,and the dislocation density of 1/6<112> Shockley is obviously positively correlated to cutting speeds at the same cutting depth.