PSI - Issue 5

Tatyana Tretyakova et al. / Procedia Structural Integrity 5 (2017) 318–324 Tatyana Tretyakova et al. / Structural Integrity Procedia 00 (2017) 000 – 000

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4. Conclusion

The present investigation has shown that the non-contact 3-D digital image correlation measurement system Vic 3D is a highly effective computer-vision-based technique, which provides estimation of the temporal instabilities and spatial localization due to the Lüders behavior and the shoulder or necking effect during uniaxial tension tests. The analysis of the inhomogeneous displacement, strain and temperature fields was carried out in accordance with the stages of material deformation. The estimation of the influence of the stress concentrators on the yield delay effect and on the processes of the initiation and propagation of the localized deformation bands during uniaxial tension tests was performed. Based on the previously considered criteria of the transition of the deformation process to the postcritical deformation stage, the evolution of the postcritical deformation zone was observed and identified on the surface of the specimens with concentrators.

Acknowledgements

The work was carried out in the Perm National Research Polytechnic University in the Center of Experimental Mechanics with support of the Russian Science Foundation (Project 16-19-00069).

References

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