PSI - Issue 33

Tatyana Tretyakova et al. / Procedia Structural Integrity 33 (2021) 1082–1088 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 8. The deformation curve of a specimen with a change of loading rate (indicated by an arrow) from 2.4 mm/min to 0.24 mm/min during uniaxial tension test. 4. Summary As a result of the implementation of the test program (Table 2), experimental data were obtained that show the effect of short-term stops and non-monotonic loading on the regularities of inelastic deformation of the Al-Mg alloy when the PLC effect manifests itself. Short stops decrease the level of critical strain when the jerky flow starts. Non monotonic tests were carried out in which, at a loading rate of 2.4 mm/min, a state of developed intermittent plastic deformation (strain level of 10%) was achieved, after which the rate decreased to 0.24 mm/min. This led to a change in the type of the PLC effect and a change in the regularities of the spatial-time inhomogeneity of plastic flow. Acknowledgements This work was carried out by using the capabilities of a large unique scientific facility (UNU) ‘A set of test and diagnostic equipment for studying the properties of structural and functional materials under complex thermomechanical influences’, which is part of the Center of Experimental Mechanics, PNRPU (Perm, Russia). The work was supported by the Russian Science Foundation (No. 20-79-10235). References Ait-Amokhtar H., Vacher P., Boudrahem S., 2006. Kinematics fields and spatial activity of Portevin–Le Chatelier bands using the digital image correlation method. Acta Materialia, Vol. 54, No.16, 4365–4371. Tretyakova, T.V., Wildemann, V.E., 2018. Plastic strain localization and its stage in Al-Mg alloys. Physical Mesomechanics 21 (4), 314-319. Daghfas O., Znaidi A., Mohamed A.B., Nasri R., 2017. Experimental and numerical study on mechanical properties of aluminum alloy under uniaxial tensile test. Frattura ed Integrità Strutturale. Vol. 39, 263‒273 Gorbatenko V. V., Danilov V. I., Zuev L. B., 2018. Plastic flow instability: Chernov–Luders bands and the Portevin-le Chatelier effect. Technical physics. The Russian journal of applied physics 62, 395–400. Tretyakova, T.V., Wildemann, V.E., 2017. Influence the loading conditions and the stress concentrators on the spatial-time inhomogeneity due to the yield delay and the jerky flow: study by using the digital image correlation and the infrared analysis. Frattura ed Integrita Strutturale 11 (42), 303-314. Tretyakova, T.V., Wildemann, V.E., Tretyakov, M.P., 2019. Investigation of the Portevin-Le Chatelier effect in metals under additional vibration impact by using the DIC-technique and the IR-analysis. Procedia Structural Integrity 18, 837-842.