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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%.

Metal matrix composites, reinforced with continuous SiC fiber, offer attractive combinations of high specific strength, specific stiffness and elevated temperature performance and are currently being considered for a range of broad prospective applications. The recent research development on SiC fiber reinforced metal matrix composite was reviewed. The key problems, solutions and application of SiC/Al, SiC/Ti, SiC/Cu, SiC/Ni composites were summarized separately. Finally, the limiting factors in the application of the metal matrix composites were point out:cost issues, interfacial problems, anisotropy of composites and lack of systematic quality estimate.