Flanging Process Simulation And Optimization

Flanging process is an important method in sheet metal forming process, and it is now widely used in aerospace and automotive industry. While the hole flanging is the most common type of flange, forming easily lead to rupture when flanging height is too large, therefore formability study on round hole flanging has important significance. At present, along with the computer simulation technology development, more and more researchers have chosen to use the computer finite element simulation method to discuss sheet metal forming process. Computer numerical simulation technology can predict in advance and effectively improve the problem such as structure and size, thus it can shorten the production cycle, reduce the production cost. And against the phenomenon, this paper adopts sheet finite element simulation software DYNAFORM and ABAQUS on the flanging simulation.Long-term since, stamping theory and engineering application deduction the stress of hole flanging process in deformation zone according to the equilibrium equation of rdσ,/dr+(σ,-σθ)=0, but this balance equation doesn’t consider the flanging process material thickness variation. Although the method about the analysis of stress and strain in flanging deformation zone is simple to apply, but clearly it is incompatible with the the fact that the thickness of the flange region significantly has changed, at the same time various influence factors in the estimation of the flanging forming process are too rough, there is a big error between the calculation results with the actual production. Therefore, considering this factor of the material thickness changes in the deformation process, using a more realistic equilibrium equations of the hole flanging is very necessary to carry out the derivation of the relationship of stress, thickness and radial radius, and it has some theoretical significance and practical significance.There are many factors effects quality of round hole flanging, from punch shape, sheet thickness to diameter ratio to the blank material properties, production process parameters and so on. Through the finite element analysis software DYNAFORM simulated to the round hole flanging process, and change the punch shape which uses parabolic convex die, conical punch and a spherical convex die for round hole flanging, contrasting with the cylindrical convex die under the same platform, and change different thickness to diameter ratio to get different flanging limit coefficient, clarifies the different shape of the punch and different thickness to diameter ratio on flanging limit produce different effects.For different material properties and process parameters have different effects on the flanging, the paper selects four material parameters and technological parameters on the orthogonal experiment design, to find the influential factors on round hole flanging thickness thinning rate. And using the finite element analysis software DYNAFORM to simulate the different factors, get the maximum edge thinning rate, which were compared to find the most influencing factors on the flanging sheet thinning. Based on analysis and comparison of the above various influence factors, there is a certain guiding significance about choice of all factors on round hole flanging.