Abstract
An experimental and theoretical study of plastic shear localization mechanisms observed under dynamic deformation using the shear–compression scheme on a Hopkinson–Kolsky bar has been carried out using specimens of AMg6 alloy. The mechanisms of plastic shear instability are associated with collective effects in the microshear ensemble in spatially localized areas. The lateral surface of the specimens was photographed in the real-time mode using a CEDIP Silver 450M high-speed infrared camera. The temperature distribution obtained at different times allowed us to trace the evolution of the localization of the plastic strain. Based on the equations that describe the effect of nonequilibrium transitions on the mechanisms of structural relaxation and plastic flow, numerical simulation of plastic shear localization has been performed. A numerical experiment relevant to the specimen-loading scheme was carried out using a system of constitutive equations that reflect the part of the structural relaxation mechanisms caused by the collective behavior of microshears with the autowave modes of the evolution of the localized plastic flow. Upon completion of the experiment, the specimens were subjected to microstructure analysis using a New View-5010 optical microscope–interferometer. After the dynamic deformation, the constancy of the Hurst exponent, which reflects the relationship between the behavior of defects and roughness induced by the defects on the surfaces of the specimens is observed in a wider range of spatial scales. These investigations revealed the distinctive features in the localization of the deformation followed by destruction to the script of the adiabatic shear. These features may be caused by the collective multiscale behavior of defects, which leads to a sharp decrease in the stress-relaxation time and, consequently, a localized plastic flow and generation of fracture nuclei in the form of adiabatic shear. Infrared scanning of the localization zone of the plastic strain in situ and the subsequent study of the defect structure corroborated the hypothesis about the decisive role of non-equilibrium transitions in defect ensembles during the evolution of a localized plastic flow.
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References
Giovanola, J.H., Adiabatic shear banding under pure shear loading. Part I: Direct observation of strain localization and energy dissipation measurements, Mech. Mater., 1988, vol. 7, no. 1, pp. 59–71.
Burns, T.J., Does a shear band result from a thermal explosion? Mech. Mater., 1994, vol. 17, nos. 2–3, pp. 261–271.
Nemat-Nasser, S., Li, Y.F., and Isaacs, J.B., Experimental/computational evolution of flow stress at high strain rates with application to adiabatic shear banding, Mech. Mater., 1994, vol. 17, nos. 2–3, pp. 111–134.
Bai, Y., Xuc, Q., Xu, Y., and Shen, L., Characteristics and microstructure in the evolution of shear localization in Ti6Al4V alloy, Mech. Mater., 1994, vol. 17, nos. 2–3, pp. 155–164.
Belytschko, T., Krongauz, Y., Organ, D., Fleming, M., and Krysl, P., Meshless methods: an overview and recent developments, Comput. Methods Appl. Mech. Eng., 1996, vol. 139, nos. 1–4, pp. 3–47.
Wright, T.W. and Ravichandran, G., Canonical aspects of adiabatic shear bands, Int. J. Plast., 1997, vol. 13, no. 4, pp. 309–325.
Medyanik, S.N., Liu, W.K., and Li, S., On criteria for dynamic adiabatic shear band propagation, J. Mech. Phys. Solids, 2007, vol. 55, no. 7, pp. 1439–1461.
Rittel, D., Ravichandran, G., and Venkert, A., The mechanical response of pure iron at high strain rates under dominant shear, Mater. Sci. Eng., 2006, vol. 432, nos. 1–2, pp. 191–201.
Rittel, D., Wang, Z.G., and Merzer, M., Adiabatic shear failure and dynamic stored energy of cold work, Phys. Rev. Lett., 2006, vol. 96, p. 075502.
Rittel, D., Landau, P., and Venkert, A., Dynamic recrystallization as a potential cause for adiabatic shear failure, Phys. Rev. Lett., 2008, vol. 101, p. 165501.
Marchand, A. and Duffy, J., An experimental study of the formation process of adiabatic shear bands in a structural steel, J. Mech. Phys. Solids, 1988, vol. 36, no. 3, pp. 251–283.
Barker, L.M., Behavior of Dense Media under High Dynamic Pressures, New York: Gordon and Breach, 1968.
Swegle, J.W. and Grady, D.E., Shock viscosity and the prediction of shock wave rise time, J. Appl. Phys., 1985, vol. 58, no. 2, pp. 692–701.
Razorenov, S.V., Kanel, G.I., Fortov, V.E., and Abasehov, M.M., The fracture of glass under high-pressure impulsive loading, High Pressure Res., 1991, vol. 6, no. 4, pp. 225–232.
Naimark, O.B., Collective properties of defect ensembles and some nonlinear problems of plasticity and fracture, Phys. Mesomech., 2003, vol. 6, no. 4, pp. 39–63.
Sokovikov, M.A., Bilalov, D.A., Chudinov, V.V., Uvarov, S.V., Plekhov, O.A., Terekhina, A.I., and Naimark, O.B., Nonequilibrium transitions in ensembles of defects attributed to dynamic localization of plastic deformation, Tech. Phys. Lett., 2014, vol. 40, no. 12, pp. 1075–1077.
Sokovikov, M., Chudinov, V., Bilalov, D., Oborin, V., Uvarov, S., Plekhov, O., Terekhina, A., and Naimark, O., Experimental and numerical study of plastic shear instability under high-speed loading conditions, AIP Conf. Proc., 2014, vol. 1623, pp. 599–602.
Bilalov, D., Sokovikov, M., Chudinov, V., Oborin, V., Terekhina, A., and Naimark, O., Numerical simulation and experimental investigation of localization of strain and fracture of metals under dynamic loading, AIP Conf. Proc., 2014, vol. 1623, pp. 67–70.
Sokovikov, M.A., Bayandin, Yu.V., Lyapunova, E.A., Plekhov, O.A., Chudinov, V.V., and Naimark, O.B., Plastic strain localization and fracture mechanisms of metals subjected to dynamic loading, Vychisl. Mekh. Sploshnykh Sred, 2013, vol. 6, no. 4, pp. 467–474.
Saveleva, N.V., Bayandin, Yu.V., and Naimark, O.B., Numerical simulation of deformation and fracture of metals under plane shock wave loading, Vychisl. Mekh. Sploshnykh Sred, 2012, vol. 5, no. 3, pp. 300–307.
Bayandin, Yu.V., Kostina, A.A., Naimark, O.B., and Panteleev, I.A., Modeling of the deformation behavior of vanadium under quasistatic loading, Vychisl. Mekh. Sploshnykh Sred, 2012, vol. 5, no. 1, pp. 33–39.
Bouchaud, E., Scaling properties of cracks, J. Phys.: Condens. Matter, 1997, vol. 9, no. 21, pp. 4319–4344.
Froustey, C., Naimark, O., Bannikov, M., and Oborin, V., Microstructure scaling properties and fatigue resistance of pre-strained aluminium alloys, Part 1: Al–Cu alloy, Eur. J. Mech. A: Solid, 2010, vol. 29, no. 6, pp. 1008–1014.
Oborin, V.A., Bannikov, M.V., Naimark, O.B., and Palin-Luc, T., Scaling invariance of fatigue crack growth in gigacycle loading regime, Tech. Phys. Lett., 2010, vol. 36, no. 11, pp. 1061–1063.
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Original Russian Text © D.A. Bilalov, M.A. Sokovikov, V.V. Chudinov, V.A. Oborin, Yu.V. Bayandin, A.I. Terekhina, O.B. Naimark, 2015, published in Vychislitel’naya Mekhanika Sploshnykh Sred, 2015, Vol. 8, No. 3, pp. 319–328.
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Bilalov, D.A., Sokovikov, M.A., Chudinov, V.V. et al. Studying plastic shear localization in aluminum alloys under dynamic loading. J Appl Mech Tech Phy 57, 1217–1225 (2016). https://doi.org/10.1134/S0021894416070038
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DOI: https://doi.org/10.1134/S0021894416070038