3D-FE modeling method of splitting spinning

The splitting spinning is one of newly rising, green flexible forming technologies. Since the splitting spinning process is a complicated plastic forming process under multi-factor effects, FE numerical simulation is adopted to research on the modeling process in order to predict and control the splitting spinning process. To establish a practical 3D-FE model for the investigation and understanding of the splitting spinning process is one of the key problems urgently to be solved in the research and development of this advanced spinning technology. In this paper, a reasonable 3D-FE model of splitting spinning has been developed under the FE software environment of ABAQUS. The procedures are summarized, and the comparisons of the modeling process between splitting spinning and traditional spinning are presented. Some key technologies are proposed, such as: (1) a formula among velocity, displacement and time is deduced to obtain the exact forming time; (2) the flow stress model is introduced to describe the strain-hardening; (3) the shear failure model is introduced to predict whether to fracture in the radial direction; (4) adaptive meshing technology is used to avoid the appearance of distorted elements; and (5) the reasonable frictional type and constraint type are defined to control the quality of flanges accurately. The model is validated by energy conservation principle and comparison with experimental data. The established 3D-FE model of splitting spinning describes the quantitative relationships between the forming conditions and the forming results by analysis of the variations of spinning force, stress field and strain field with time, and it provides the basis for the determination and optimization of the splitting spinning process. Furthermore, the modeling method is also of general significance to hot or other states of splitting spinning.