PSI - Issue 2_A

Tretyakov M.P. et al. / Procedia Structural Integrity 2 (2016) 3721–3726 Tretyakov M.P./ Structural Integrity Procedia 00 (2016) 000 – 000

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Because of the tests under sequential tension and torsion by the procedures are obtained the qualitative characteristics of the alteration of stiffness of specimens during torsion after previous different level postcritical deformation during uniaxial tension. After torsion and unloading down to zero torque, the residual angle of torsion is observed. Increasing of previous level of postcritical deformation during tension is leaded to decreasing of torsion strength and stiffness of specimens. It could occurs due to changings of geometrical characteristics of the specimens, and to postcritical softening of material. Experimental study of the postcritical deformation stage at various types of the stress-strain state is necessary for obtaining new data for creating and developing of the mechanical models of softening media. Future experimental and theoretical study continuation of the postcritical deformation stage is very important for different structural materials, especially for heterogeneous materials, such as composites, and necessary for forecasting of the behavior of materials in emergency cases and failure processes propagation.

Acknowledgements

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

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