Friction modeling between the tool and the workpiece plays an important role in predicting the minimum cutting thickness during TC4 micro machining and finite element method(FEM)cutting simulation.In this study,a new ...Friction modeling between the tool and the workpiece plays an important role in predicting the minimum cutting thickness during TC4 micro machining and finite element method(FEM)cutting simulation.In this study,a new three-region friction modeling is proposed to illustrate the material flow mechanism around the friction zone in micro cutting;estimate the stress distributions on the rake,edge,and clearance faces of the tool;and predict the stagnation point location and the minimum cutting thickness.The friction modeling is established by determining the distribution of normal and shear stress.Then,it is applied to calculate the stagnation point location on the edge face and predict the minimum cutting thickness.The stagnation point and the minimum cutting thickness are also observed and illustrated in the FEM simulation.Micro cutting experiments are conducted to validate the accuracy of the friction and the minimum cutting thickness modeling.Comparison results show that the proposed friction model illustrates the relationship between the normal and sheer stress on the tool surface,thereby validating the modeling method of the minimum cutting thickness in micro cutting.展开更多
In flat jet electrochemical milling, the electrolyte forms a backward parallel flow after impacting the workpiece, resulting in a weak current density distribution on the workpiece. Poor surface quality usually occurs...In flat jet electrochemical milling, the electrolyte forms a backward parallel flow after impacting the workpiece, resulting in a weak current density distribution on the workpiece. Poor surface quality usually occurs on the machined titanium alloy surface because it inevitably suffers from the weak current density. In this study, a method of flat jet electrochemical milling with tailoring the backward parallel flow was proposed to eliminate the negative effects caused by the weak current density. Multiphysics simulations are carried out to comprehend the mechanism of flat jetEC milling with tailoring backward parallel flow and better construct the novel tool electrode.Experiments on flat jet electrochemical milling of TC4 alloy with and without tailoring backward parallel flow are conducted. The results reveal that, compared with flat jet electrochemical milling without tailoring backward parallel flow, the recommended tool reduces the surface roughness by86% to 93%, and improves the material removal rate by 93% to 163% with different feed rates.Additionally, the recommended tool is more conducive to maintaining the inherent hardness of the material. Finally, a surface with low Sa of 0.37 μm is obtained.展开更多
文摘Friction modeling between the tool and the workpiece plays an important role in predicting the minimum cutting thickness during TC4 micro machining and finite element method(FEM)cutting simulation.In this study,a new three-region friction modeling is proposed to illustrate the material flow mechanism around the friction zone in micro cutting;estimate the stress distributions on the rake,edge,and clearance faces of the tool;and predict the stagnation point location and the minimum cutting thickness.The friction modeling is established by determining the distribution of normal and shear stress.Then,it is applied to calculate the stagnation point location on the edge face and predict the minimum cutting thickness.The stagnation point and the minimum cutting thickness are also observed and illustrated in the FEM simulation.Micro cutting experiments are conducted to validate the accuracy of the friction and the minimum cutting thickness modeling.Comparison results show that the proposed friction model illustrates the relationship between the normal and sheer stress on the tool surface,thereby validating the modeling method of the minimum cutting thickness in micro cutting.
基金supported by Defense Industrial Technology Development Program (Grant No. JCKY2021605B003)National Natural Science Foundation of China for Creative Research Groups (Grant No. 51921003)Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No. KYCX20_0181)。
文摘In flat jet electrochemical milling, the electrolyte forms a backward parallel flow after impacting the workpiece, resulting in a weak current density distribution on the workpiece. Poor surface quality usually occurs on the machined titanium alloy surface because it inevitably suffers from the weak current density. In this study, a method of flat jet electrochemical milling with tailoring the backward parallel flow was proposed to eliminate the negative effects caused by the weak current density. Multiphysics simulations are carried out to comprehend the mechanism of flat jetEC milling with tailoring backward parallel flow and better construct the novel tool electrode.Experiments on flat jet electrochemical milling of TC4 alloy with and without tailoring backward parallel flow are conducted. The results reveal that, compared with flat jet electrochemical milling without tailoring backward parallel flow, the recommended tool reduces the surface roughness by86% to 93%, and improves the material removal rate by 93% to 163% with different feed rates.Additionally, the recommended tool is more conducive to maintaining the inherent hardness of the material. Finally, a surface with low Sa of 0.37 μm is obtained.