| Computer Aided Engineering is an important part of advanced manufacture technology, and is the key to improving the ability of product design, process planning, and die design and for enterprises changing the traditional design style depending on experience for enterprise. With the development of computer technology, in-depth study of finite element numerical method and stamping deformation theory, the technology of sheet forming analysis has been gradually matured and could be applied in the complete stamping process from gravity effect to springback evaluation to meet the requirements of manufacturing industry. At the same time, CAD/CAE integrated systems have been developed, which have the advantages of seamless integration and no data loss over the traditional CAE systems. The development of CAD/CAE integration technique greatly expands the application scope of CAE technology, and gradually approaches the aim of CAE-driven design process.The work of this paper was supported by a grant from National Natural Science Foundation of China (No.50575080), National Key Technology R&D Plan (No. 2006BAF01A43) and National High-Tech Plan Project (No. 2006AA04Z140). On the basis of the in-depth study on the key technologies such as solver, pre-processing, post-processing and CAD/CAE integration, the first domestic sheet forming analysis system for the complete stamping process planning named FASTAMP/Multi-process and CAD/CAE integrated system named FASTAMP-NX have been developed.A new technique of constraint resistance treatment by the means of linear elastic spring element model in sheet metal forming process is proposed based on the dynamic explicit incremental method, which can be applied to build the more accurate model of process parameters such as blank holding force, drawbead and friction, to reflect the effect of the process parameters. An adaptive mesh refining and coarsening has been developed, and applied to the solver of the developed improved dynamic explicit incremental approach. As a result, the simulation time consumed is greatly reduced, and an ideal balance between time consumed and calculation precision is achieved.The key techniques for sheet forming analysis system, such as CAD data transfer interface, curve and surface description and mesh generation, have been studied in-depth. The compatibility and stability of intermediate data transfer interface for FASTAMP is greatly enhanced .Based on independent surface trimming, a new meshing algorithm is developed for tool mesh generation and auto-repairing so that the mesh quality is obviously improved, and the time consumed for FEA model building and mesh repairing are greatly reduced. The new initial blank mesh generating algorithm based on outline trimming is also proposed, which can be applied to get better mesh quality than traditional part mesh generating algorithm.Based on the research of the key technologies, a sheet forming analysis system named FASTAMP/Multi-process for the complete stamping process planning for the automobile panels and progressive tooling has been developed. It enables analyzing the entire sheet forming process– from blank feeding into the press, to binder wrap, drawing, trimming, restriking, flanging, bending and springback so that the number of die tryouts is reduced, , and the lead-time for tooling development is reduced.A parametric CAD/CAE seamlessly integrated system named FASTAMP-NX has been developed based on UGS NX platform, which includes two subsystems, IAW for design of sheet metal parts and stamping dies and FAW for virtual tryout. With the unique parametric feature model and associated design technology, the integrated system can be applied to the whole process of the product and die development, including conceptual design, detail design, process planning and virtual die tryout to realize the real CAE-driven design process, the final goal of CAE.
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