Prediction of Fineblanked surface characteristics using the finite element method (FEM)

The requirements for the fineblanking (FB) technology that the precision blanked products could be obtained are more demanding. Therefore, the optimal die design and working conditions determined by a proven database and trial-and-error processes are insufficient. In this study, the possibility of using the finite element method (FEM) was investigated to analyze the blanked surface in FB process by using 2D-FEM, and the mechanism of tearing and/or secondary shear surface formation on fineblanked surface was also clarified. The reasonable number of meshes, adaptive remeshing technique and suitable ductile fracture criterion equation were used. The results initially indicated that the occurrence of tearing and/or secondary shear surface can be analyzed by the FEM simulation and its mechanism can also be explained. From those results, the FEM model of the fineblanking process enabling surface flaws to be predicted could be created. The FEM simulation results compare well with experimental results, thus validating the method for predicting the blanked surface quality. Therefore, it was indicated that FEM simulation could be a useful tool for predicting a fineblanked surface and determining design and working parameters in the FB process.