PSI - Issue 13

Ivan Smirnov et al. / Procedia Structural Integrity 13 (2018) 1336–1341 Ivan Smirnov et al. / Structural Integrity Procedia 00 (2018) 000 – 000

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less than that of the CG initial material and depends on the number of ECAP passes. This can lead to intersection of the stress rate dependencies of the materials at higher loading rates. 2. The analysis of the loading diagram and values of consumed energy for beams with a V-notch under impact loading allowed us to establish the behaviour and quantitative parameters of load bearing capacity of the UFG copper specimens in the presence of a crack-like defect. In comparison with CG copper in the delivery state, the UFG material showed higher energy consumption (impact toughness) before a force peak. In comparison with the annealed CG copper, the UFG material showed higher energy consumption for the entire process of deformation and fracture at test temperatures of -50, room temperature and 100 °C.

Acknowledgements

The work was carried out within the framework of the Grant of the President of the Russian Federation for young scientists (MK-2587.2017.1). Research was conducted using equipment of the Centre for Extreme States of Materials and Constructions, as well as the Interdisciplinary Center for Nanotechnology at the Research Park of Saint Petersburg University.

References

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