Finite Element Modeling And Simulation Of Metal Cutting Process

Metal cutting process is a very complicated nonlinear process. By classical research technique, it is very difficult to give a quantitative analysis of metal-cutting mechanics. Applying the computer in finite element simulation research has many advantages, such as: good systematicness, good succession and good continuity. Besides, the research is not limited by time and space. Once good simulation results are achieved, the time and the cost of technological design can be cut down greatly. By finite element simulation, information, which is difficult or impossible to be obtained previously by lab method, can now be gained. The deformation and the temperature change in cutting process can be reproduced. By finite element simulation, technological parameters' influence on cutting process can be analyzed conveniently, which provides a theoretic and practical method for optimizing cutting technology and improving the accuracy and performance of the product and which makes the research of metal cutting theory more conveniently. Studies about modeling and simulation of metal cutting process are carried out in this paper from the following aspects:1. It is based on knowledge of material nonlineraity and geometric nonlineraity that the solution procedure of large elastic-plastic deformation is researched.2. Processing of key techniques and construction of simulation system are researched. The large-scale commercial software MSC.Marc is used as finite element simulation software.3. The reasons of chip curling are discussed and the mathematical model of the chip thickness and curling radius is set up. The 3-D real-time simulation under different cutting conditions is obtained. The conditions of stress, strain and temperature distribution in cutting and workpieces in machining are gained. By changing cutting conditions, including undeformed chip thickness, cutting speed, tool orthogonal rake, and analyzing cutting condition's influence on chip, finite element simulation result of chip curling under the condition of oblique cutting is obtained. Simulation result achieves high consistency with the relative lab result. It indicates that finite element model has certain practical and theoretical value in the control of chip forming.4. Reasons and influencing factors of metal burr formation are discussed; mathematical model in cutting direction burr is set up; forming process and mechanism of cutting direction burr under orthogonal cutting are simulated and analyzed; cutting condition's influence on burr formation is analyzed by changing cutting conditions. Comparison between simulation result and lab result indicates that finite element model has certain practical and theoretical value in giving a quantitative prediction of burr dimension.