Virtual Forming Application Technology Research Of Sheet Metal

Sheet metal stamping is an extremely important process for the forming of parts and is widely used in automobile, aircraft, electronics instrument and other industries.The physical phenomena in sheet metal stamping are very complicated, including three nonlinear problems (material, geometry and boundary) of the mechanics science, so the quality of designing is qiuet difficult for some complicated forming process and it's die. Some important parameters can be confirmed only after the die had been produced and then been reparied for several times. Time and resource are wasted by this way. With the development of finite element method and computer technique, numerical simulation has become the effective technology tool of analysis and optimal design gradually.Along with the development of the automobile and aircraft industries in our country, the technology analysis of the sheet metal forming are greatly needed. The computer aided engineering software about sheet metal forming must be found widely application. Today, the theoretical basis and methods are introduced in most CAE disquisition, but how to deal with the idiographic operations is seldom mentioned in them.Based on the situation, the paper does research as follows:In this paper, the state and development of simulation of sheet metal stamping processes are summarized, and the characterisitcs of the software used in the research such as UG and DYNAFORM are introduced too. The change of microstructure and the stress-strain in material forming processes are analyzed theoretically. The basic rules of the finite element method technique are presented, the selected dynamic explicit algorithm, material model and shell element model used in the simulation are also explained in detail. Based on the above investigations, some practical problems appeared in the pre-processing of DYNAFORM are more discussed, including: the distortion and modifiability of the model transformed in the form of IGES, the manual repair of the disfigurement in the model meshing , and the design of the binder sruface and the addendum in the complex die.The familiar forming defects are analyzed theoretically, while the simulation analysis of some representative examples, such as the deep-drawing of couple stainless washing box, the lamp-shell of the car, the complex automobile front floor and so on,...