PSI - Issue 18

Evgeny Lomakin et al. / Procedia Structural Integrity 18 (2019) 549–555 Evgeny Lomakin and Boris Fedulov / Structural Integ ity Procedia 00 (2019) 000–000

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Fig. 7. Discrepancy of predictions of the yield points in experiments on biaxial tension for the von Mises criterion and the criterion in the form (2) with coefficients corresponding to the diagrams in Fig. 6. Points 1-6 on the vertical axis correspond to the numbers of experiments. 4. Conclusion It is demonstrated by the consideration of an example of aluminum alloys, with pressure treatment step in their manufacture, that the material has a distinct anisotropy of plastic properties and they are sensitive to the type of loading. The modelling of such a material may be realized by the proposed plasticity criterion based on the modification of Hill’s plasticity condition, taking into account all of the described effects. The proposed criterion has been compared with classical von Mises one with the use of the results of biaxial tests. The analysis shows that the precision of proposed criterion is less than one percent, while for Mises surface maximum deviation is of 12 percent for non-conservative prediction. Acknowledgements This research was supported by the Russian Foundation for Basic Research (Grant no. 18-31-20026) and Russian Science Foundation (Grant no. 16-19-00069) in part of the analysis of experimental data. MIL-HDBK-5J (2003) Jordon, J. B., Horstemeyer, M. F., Solanki, K., Bernard, J. D., Berry, J. T., & Williams, T. N. (2009). Damage characterization and modeling of a 7075-T651 aluminum plate. Materials Science and Engineering: A, 527(1-2), 169-178. De Jong, H. F. (1980). Thickness direction inhomogeneity of mechanical properties and fracture toughness as observed in aluminum 7075-T651 plate material. Engineering Fracture Mechanics, 13(1), 175-192. Lomakin, E. V. (2011). Constitutive models of mechanical behavior of media with stress state dependent material properties. In Mechanics of Generalized Continua (pp. 339-350). Springer, Berlin, Heidelberg. Lomakin, E. V., Fedulov, B. N., & Melnikov, A. M. (2014). Constitutive models for anisotropic materials susceptible to loading conditions. In Mechanics and Model-Based Control of Advanced Engineering Systems (pp. 209-216). Springer, Vienna. Lomakin, E. V., & Fedulov, B. N. (2013). Plane strain extension of a strip made of a material with stress state type dependent properties and weakened by cuts with circular base. Mechanics of Solids, 48(4), 424-430. Hill, R. (1948). A theory of the yielding and plastic flow of anisotropic metals. Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 193(1033), 281-297. Korkolis, Y. P., Kyriakides, S., Giagmouris, T., & Lee, L. H. (2010). Constitutive modeling and rupture predictions of Al-6061-T6 tubes under biaxial loading paths. Journal of Applied Mechanics, 77(6), 064501. References