INFLUENCES OF THE GRAIN BOUNDARY ON THE CUTTING TEMPERATURE OF IRON CUTTING TEETH

In this study, molecular dynamics simulation was employed to analyze the temperature changes in pure iron models using the same cutting process. Thus, the effects of a micro-grain boundary on the cutting temperature change of the cutting teeth were investigated. The cutting teeth are key parts of a heading machine and wear-out failure is a significant factor influencing the extent of their lifetime. In this study, nanoscopic cutting models for both single-crystal and polycrystalline iron were developed. The results showed that the thermal conductivity of the polycrystalline iron model was much lower than that of the single-crystal iron model, and the entanglement and accumulation of grain boundary dislocations enhanced its ability to resist plastic deformation. The strength of polycrystalline iron was improved, and more cutting heat was generated, resulting in a higher cutting temperature in the polycrystalline iron model. The developed approach is of practical significance in research on the wear-out failure of cutting teeth.