Microstructural evolution of polycrystalline α-Fe/Fe3C ultra-precision grinded under water lubrication

Abstract

Ultra-precision grinding has gained substantial attention for its ability to significantly improve surface integrity. However, existing studies rarely investigate the effects of lubrication conditions at the microscopic level, which limits the understanding of microstructure evolution during ultra-precision grinding. In this work, a large-scale molecular dynamic (MD) method is proposed for simulating microstructural evolution of polycrystalline α-Fe/Fe₃C ultra-precision grinded under water lubrication. The water molecule and polycrystalline α-Fe/Fe₃C models are established using the measured and calculated interatomic potential functions. The effects of grinding parameters (infeed depth and lubrication status) on the ultra-precision grinding of internal stresses, temperature fields, workpiece topography and plastic deformation are investigated. Results show that the water film has a beneficial impact on workpiece quality, but has a negative effect on grinding efficiency. The plastic deformation mechanism of ultra-precision grinded polycrystalline α-Fe/Fe₃C primarily involves dislocation modulation, with the water film serving to reduce dislocations and promote cluster formation. This work offers valuable insights into the production of high-quality components.