PSI - Issue 6

N.S. Selyutina et al. / Procedia Structural Integrity 6 (2017) 77–82 Author name / StructuralIntegrity Procedia 00 (2017) 000 – 000

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4. Conclusions

Relaxation model of plasticity, based on explicit introduction of the characteristic time of relaxation as a material constant, satisfactory predicts the behaviour of the yield strength in a wide range of strain rates. The approach developed here provides one the possibility to construct the deformation (stress-strain) curves defined by means of the proposed integral plastic flow criterion. It is proved that the proposed technique can also effectively predict the behaviour of deformation curve during its softening stage. An advantage of the flow stress calculations based on the incubation time criterion, in contrast to the empirical Johnson – Cook model, is the minimum number of parameters, which do not require further modifications at high strain rates.

Acknowledgements

The work was supported by the Russian Science Foundation (grant 17-71-10061).

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