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Superalloy has excellent comprehensive properties and is the preferred material for high performance components of aeroengine. Due to its high yield strength and obvious springback, it is difficult to control the forming precision of superalloy component. Therefore, it is crucial to study the applicability of cyclic constitutive models in the deformation simulation of superalloy foils. Based on the cyclic shearing test, the characterization effects of different cyclic plastic constitutive models on the cyclic plastic deformation response of superalloy were studied. By comparing the results of U-bending test with the simulation results of finite element software, the accuracy of springback prediction of different yield criteria combined with different cyclic plastic constitutive models was analyzed. The results show that Y-U (Yoshida-Uemori) model has the best characterizing effect on the response of cyclic plastic deformation, while A-F (Armstrong-Frederick) model and ANK (the anisotropic nonlinear kinematic) model have close characterizing effect. For the prediction accuracy of springback, the fitting accuracy of Y-U model is higher than that of isotropic model and A-F model. However, the yield criterion has little influence on the prediction accuracy of springback. The prediction deviation of Y-U model based on Hill48 yield criterion and YLD-2000 yield criterion can be controlled within 5%.

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In recent years, in order to improve the precision of the springback prediction, many advanced material constitutive models have been developed to describe the complex material behavior of sheet metal upon load reversals. The Yoshida-Uemori (Y-U) and the homogeneous yield function-based anisotropic hardening (HAH) models are typical models which are able to predict the Bauschinger effect, transient hardening and permanent softening phenomena. The heavy identification efforts raise to be one main chanllenge before their application due to the numerous parameters. Appropriate tests and robust optimal methods are needed to calibrate parameters. In this work, cyclic stress-strain curve of DP780 steel sheets are obtained by tension-compression tests, and then the parameters of modified Y-U and HAH model are identified through global optimization approach. The identified parameters are verified by the comparison between springback results of U-shape draw-bending process and simulation. [ABSTRACT FROM AUTHOR]