PSI - Issue 5

Terekhina Alena et al. / Procedia Structural Integrity 5 (2017) 569–576 Terekhina Alena et al. / Structural Integrity Procedia 00 (2017) 000 – 000

576 8

Fig 6. Accuracy of the TCD based on elasto-plastic analysis in predicting the strength.

4. Conclusions

In this study modification of the classical theory of critical distance in cases of elasto-plastic material behavior for quasistatic and dynamic loading was proposed. Accounting plasticity has been implemented with the use of the simplified Johnson-Cook model. The parameters for this model were identified from experimentally determined stress-strain curves by curve fitting techniques. The results of elasto-plastic analyses of stress distributions near a wide variety of notches are presented. The results showed that the use of the modification of the TCD based on elasto plastic analysis gives us estimates falling within an error up to 12%, that is good engineering estimate. The use of an improved description of the stress-strain state at the notch tip allows introducing the critical distances as a material parameter.

Acknowledgements

The authors would like to acknowledge the financial support of the RFBR grants 16-31-00156 and 16-48-590148.

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