This paper focuses on improving the forming precision of Z-shaped profiles with large-section in the four-roll bending process. An analytical springback model is established for Z-shaped profiles with large-section by introducing neutral layer shift, considering the influence of material properties, geometric parameters, and forming radii on the springback. The bending springback laws of 7075-O and 7475-O aluminum alloy Z-section profiles under different forming radii are studied, and roll bending tests are carried out to validate the springback model. The results indicate that compared with the empirical model which ignores the influence of neutral layer shift, the proposed model based on neutral layer shift can accurately predict the springback for Z-shaped profiles with large cross-section. The maximum relative error of predicting springback deformation for Z-shaped profiles with the same radius of curvature changes from 11.681% to 3.347%.
WANG Anheng
,
XUE Hongqian
,
YANG Yanli
,
WEI Yaoguang
. Springback prediction for Z-shaped profiles in roll bending process based on neutral layer shift[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2019
, 40(12)
: 423127
-423127
.
DOI: 10.7527/S1000-6893.2019.23127
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