On Orthotropic Elastic Constitutive Modeling for Springback Prediction

Background

The conventional isotropic elastic model neglects the anisotropy of sheet metals' elastic modulus, leading to inevitable errors in springback prediction.

Objective

Aiming at the problem of anisotropic springback in the forming process of sheet metals, an orthotropic elastic model was established in this study, and the applicability of the model was analyzed. An accurate and convenient numerical solution method was proposed, considering the challenge of calibrating model parameters through experimental measurement.

Methods

The reliability of the proposed parameter solution method is verified by uniaxial tensile and thin-walled tube torsion tests. To verify the anisotropic elastic model, both V-bending finite element simulation and experimental testing were conducted.

Results

The proposed parameter solution method has good prediction accuracy, with an average relative error within 5%. The three-group sample solution method significantly reduces experimental and data processing workload, demonstrating the precision and user-friendliness of this method. The proposed model yields a significant enhancement in springback prediction accuracy when compared to the conventional isotropic elastic model.

Conclusion

This study is basic research on the prediction of anisotropic springback, which can improve the simulation accuracy of the sheet metals forming process involving this problem, particularly in the anisotropic metal sheet stamping process.