# A Coupled Armstrong-Frederick Type Plasticity Correction Methodology for Calculating Multiaxial Notch Stresses and Strains

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## Abstract

Based on the pseudo-strain method, a computational modeling technique coupling with Armstrong-Frederick type nonlinear kinematic hardening rule (Jiang-Sehitoglu model) is developed to calculate the multiaxial stress-strain responses of notched components. The pseudo-strain-true notch stress curve is determined using Neuber’s rule. The material constants in Jiang-Sehitoglu model are calculated using the Ramberg-Osgood curve. The presented method is applied to simulate the notch-tip deformations of circumferentially notched 1070 steel and S460N steel shafts subjected to various loadings, including box, circle, V-shape, zigzag-shape, and butterfly-shape loading paths. The calculated strain loops are in accord with experimental data and show reasonable accuracy.

## Keywords

Notch-tip stress-strain Plasticity model Pseudo-strain Multiaxial cyclic loading## Notes

### Acknowledgment

The authors gratefully acknowledge the financial support of the National Natural Science Foundation of China (Nos. 51601221 and 51575524), the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2015JM5240) and the Doctoral Scientific Research Foundation of Air Force Engineering University.

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