Research On The Forming Limit And Springback Control Of Numerical Incremental Sheet Metal Forming Technology

Present day developing industries deal with a wide spectrum of components. In spite of extensive efforts being made with regards to virtual process optimizing technology, the production of prototype parts is still a necessity. The conventional means of manufacturing is suitable in case the required volume is high. If the demands are small in number or if it is a prototype component, the investment in tooling for such processes may not be justified. Therefore, it becomes imperative to explore new flexible manufacturing technologies. One such technology, which allows the production of complex parts by drastically reducing costs in tooling and in machinery, is Numerical Control Incremental Sheet Metal Forming (NCISMF). In NCISMF process, the desired shape is obtained using a fixed form defining support tool with an active small-size-forming tool, programmed to requirement. The aim of the presented dissertation is to optimize the NCISMF process through surface reconstruction after considering process-induced disturbances.In NCISMF, the blank thickness, being the function of apex angle, is of significant influence, thereby arises the need to calculate a surface taking required final geometry and thickness influences into account. But by influences of error measurements, it is very hard to get the accurate thickness after proceesing. Therefore another measurement must be taken into considering, so the forming limit is a better choice. Additionally it is also necessary to consider spingback and make suitable adjustments in the surface so that the error between the produced geometry and required final geometry is minimal. Two separate custom-developed programs have to be developed to fulfill both the above requirements.To solve the split and spingback, the surface reconstruction provides a good choice. Thus several methods of surface reconstruction principles are introduced in this paper by comparing advantages and disadvantages between each methods . The surface reconstruction provides the necessary technical support for the finite element numerical simulation (FEM) also. Farthemore to control springback several shaping methods are compared, respectively, the impact on the quality of workpiece and cost are analysisd by the use of various shaping methods. So it is a comprehensive guidance for forming workpieces with different requirements.The ultimate focus is to gain knowledge by experiment and FEM to establish a set of forecasts, evaluation of NCISMF of sheet metal, that means the qualified parts can be achieved by the use of this knowledge system, and when defects come out this knowledge system can provide solutions during the forming process. Therefore, comprehensive use of the experimental study, theoretical analysis, numerical simulation and artificial neural networks, multi-database tools to predict, evaluate and solve the incremental sheet forming process in the NC common problem provides a simple and practical tool.