Research on the effect of cutting parameters on the machinability of polycrystalline Fe-Cr-W alloy by molecular dynamics simulation

Abstract

Molecular dynamics simulation has become a major theoretical analysis method for ultra precision machining of various materials. Large Scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) is used to construct a molecular dynamics model for cutting polycrystalline Fe-Cr-W alloy with CBN tool. The geometric parameters of the tool model are: the rake angle is −10°, the clearance angle is 7°, and the tool tip radius is 1.5 nm, including 8570 atoms. The size of the workpiece model is 24 nm × 10 nm × 10 nm, including 203,893 atoms. Ovito is used to visually analyze the influence of cutting parameters on the machinability of workpieces. The results show that the extrusion of the tool on the workpiece makes the atoms of the workpiece move and become chips and machined surfaces. Excessive cutting speed and depth will produce large hydrostatic stress, large cutting force, high cutting temperature and deteriorate the machined surface.