The micro-drilling process fine modeling with the strain characteristics of undeformed chip considered

Due to the cross-scale phenomenon in micro-drilling, the cutting mechanism is diverse, which leads to the large deviation of traditional cutting modeling based on constant undeformed chip thickness (UCT). So the more accurate modeling of cutting force and temperature is necessary. Firstly, drill tip is considered as the combination of multi cutting elements, and mechanical model for any element is given. Then, calculation method of strain characteristics of undeformed chip (UCS) and corresponding revised method for model are given to realize the fine modeling. Based on mechanical model, heat partition coefficient in plough-slip is given. Finally, cutting experiment is carried out to verify the accuracy of model. The results show that this method can improve the accuracy of predictive force compared with traditional ways, especially the difference between predicted value and experimental value decreased by 60.47 % in plough-slip. Furthermore, the heat more flows into tool is unfavorable to surface processing in plough-slip.