Research On Simulation Technology Of Machining Complex Surface

Cutting is the method which remove excess material layer to get the desired work piece, size and surface smoothness on the material surface by using tools. To improve the efficiency of cutting and processing quality of precision cutting and ultra-precision cutting, it needs to further study the mechanism of cutting and chip formation theory. Research shows that the numerical method is the effective means to study the process of cutting. The paper select commercial software DEFORM to simulate and analyze the cutting process of complex surface. It takes the DEFORM-3D as main tool to simulate process of metal cutting and computation, and takes FORTRAN as the interface language of DEFORM-3D to secondary development and supporting calculation.Firstly, on the base of finite element theory and rigid-plastic forming theory, rigid plastic finite element model of three-dimensional thermal couple of metal cutting is established, and the material model, contact friction model, wear model, the grid-partition method are also determined. Base on DEFORM-3D pre module of DEFORM-3D software, the three-dimensional process of metal cutting is successfully simulated, cutting force data,stress and strain distribution,temperature distribution and the formation process of the chip are obtained, the correctness of simulation results is proved, which lay the basic of establishing finite element model of complex cutting surface.Secondly, based on Windows platform, it makes secondary development to DEFORM-3D software. Through the user subroutine feature of DEFORM-3D, the custom mold or the work piece motion method is found. By inserting model which can make mold moving as specified path and overcoming the defect of that DEFORM-3D software can only do a simple straight lines or rotary movement; it makes that simulating the complex surface by DEFORM-3D software possible.Finally, on the basic of the finite element model establishing as before, it builds geometric simulation model of machining process of planar curve contouring, by applying the DEFORM-3D software after secondary development. At the foundation of researching geometry simulation and analyzing cutter position, the method which can get the cutting path of complex surface is discussed. At the end, through gradual optimization algorithm, it finishes the simulation of cutting process of curves and surfaces. After comparing the cut curves (surfaces) to the original curves (surfaces), it can be found they are good agreement in most areas. This result confirms the correctness of the added motion model. It also shows that the model can move as the path of user specifies. All of this can verify the second development of DEFORM-3D software is successful.