Metal Forming Forming Computer-aided Geometric Simulation Technology

Sheet metal stamping is a very importment manufacturing technologies, but the deformations of stamping are complex processes. In the process of the sheet metal stamping , the quality of the final product is influenced by the shape of the blank and the regulation of strain distribution during the plastic deformation . The reasonable shape of the blank can improve the formability of the sheet metal, make full use of the material, decrease the work of finishing repair.In this paper , the technology of large deformation square grid and the geometrical simulation which is closely allied with the square grid strain analysis, are studied deeply. Compared with several strain determination models to evaluate large deformations from square grids, the author uses one technique to analyze the overall strain distribution of a part. The results match actual forming process well. Based on above research, this paper entirely investigates the theory system of geometrical simulation method and proves its scientific rigor.And based on the software of MSC.Patran ,the paper creates an module to create the model of stamping part, create the mesh on the part based on the dividing line , deal with the nodes' coordinate and connection automatically , calculate and predict the shape of the blank and draw the strain distribution on the mesh. The detailed research performed is as followed:(1) The key technology of sheet metal stamping is studied .The paper confirms that the deformation of the stamping follows the large deformation , supposes that the deformation mode is purely uniform deformation and makes use of the square grid to calculate the starin of the stamping.(2) Compared with several strain determination models to evaluate large deformations from square grids, the paper choose the method by constructing the symmetrical tensor to calculate the deformation strain.The conception of forming limit is researched ,and the author also put forward the importance of the FLD.(3)The whole process of geometrical simulation put forward by R.Sowerby and...