This paper studies the micro-cutting characteristics of aluminum alloy (2A12) based on a series of orthogonal experiments and finite element method (FEM) simulations. An energy-based ductile failure law was proposed i...This paper studies the micro-cutting characteristics of aluminum alloy (2A12) based on a series of orthogonal experiments and finite element method (FEM) simulations. An energy-based ductile failure law was proposed in the FEM simulation. The simulated cutting forces and chip morphology were compared with experimental results. The simulation result indicates that there is a close relationship between the cutting force and cutting heat. The micro-cutting force decreases as the heat flux vector increases. Both the cutting heat and the micro-cutting force need a finite time to achieve a steady state. It is observed that with the cutting speed of 169.95 m/min and uncut chip thickness of 6 μm, the heat flux vector in the workpiece increases to a stable value after 0.06 ms; meanwhile, the principal cutting force decreases to a steady state correspondingly, i.e., the micro-cutting process achieves the steady state. It is concluded that the steady state micro-cutting simulation can reflect the cutting process accurately.展开更多
Three-dimensional molecular dynamics(MD)simulation was carried out to understand the mechanism of water lubrication in nanometric cutting.The water-lubricated cutting was compared with the dry cutting process in terms...Three-dimensional molecular dynamics(MD)simulation was carried out to understand the mechanism of water lubrication in nanometric cutting.The water-lubricated cutting was compared with the dry cutting process in terms of lattice deformation,cutting force,heat and pressure distribution,and machined surface integrity.It was found that water molecules effectively reduce the friction between the tool and workpiece,the heat in the cutting zone and the pressure being generated on the tool surface,thus leading to prolonged tool life.Water molecules also enlarged the pressure-affected area,which decreased the roughness of the machined surface.展开更多
基金Supported by the National High Technology Research and Development Program of China ("863" Program, No.2008AA042509)
文摘This paper studies the micro-cutting characteristics of aluminum alloy (2A12) based on a series of orthogonal experiments and finite element method (FEM) simulations. An energy-based ductile failure law was proposed in the FEM simulation. The simulated cutting forces and chip morphology were compared with experimental results. The simulation result indicates that there is a close relationship between the cutting force and cutting heat. The micro-cutting force decreases as the heat flux vector increases. Both the cutting heat and the micro-cutting force need a finite time to achieve a steady state. It is observed that with the cutting speed of 169.95 m/min and uncut chip thickness of 6 μm, the heat flux vector in the workpiece increases to a stable value after 0.06 ms; meanwhile, the principal cutting force decreases to a steady state correspondingly, i.e., the micro-cutting process achieves the steady state. It is concluded that the steady state micro-cutting simulation can reflect the cutting process accurately.
基金supported by the National Natural Science Foundation of China (Grant No. 90923038)the National Basic Research Program of China ("973" Project) (Grant No. 2011CB706703)the "111" project by the State Administration of Foreign Experts Affairs and the Ministry of Education of China (Grant No. B07014)
文摘Three-dimensional molecular dynamics(MD)simulation was carried out to understand the mechanism of water lubrication in nanometric cutting.The water-lubricated cutting was compared with the dry cutting process in terms of lattice deformation,cutting force,heat and pressure distribution,and machined surface integrity.It was found that water molecules effectively reduce the friction between the tool and workpiece,the heat in the cutting zone and the pressure being generated on the tool surface,thus leading to prolonged tool life.Water molecules also enlarged the pressure-affected area,which decreased the roughness of the machined surface.
