Issue 43

M.P. Tretyakov et alii, Frattura ed Integrità Strutturale, 43 (2018) 146-154; DOI: 10.3221/IGF-ESIS.43.11 154 [14] Chu, X., Leotoing, L., Guines, D., Ragneau, E., Temperature and strain rate influence on AA5086 Forming Limit Curves: experimental results and discussion on the validity of the M-K model, International Journal of Mechanical Sciences, 78 (2014) 27-34. DOI: 10.1016/j.ijmecsci.2013.11.002. [15] Wildemann, V.E., On the solutions of elastic-plastic problems with contact-type boundary conditions for solids with loss-of-strength zones, J. Appl. Maths Mechs, 62(2) (1998) 281. [16] Faleskog, J., Barsoum, I., Tension-torsion fracture experiments. Part I: Experiments and a procedure to evaluate the equivalent plastic strain, International Journal of Solids and Structures, 50(25–26) (2013) 4241–4257. DOI: 10.1016/j.ijsolstr.2013.08.029. [17] Tretiakov, M.P., Vildeman, V.E., Tests in tension-torsion conditions with descending sections of strain curve construction, Fracture and Structural Integrity, 24 (2013) 96–101. DOI: 10.3221/IGF-ESIS.24.10. [18] Tretyakov, M.P., Experimental investigation of the postcritical deformation stage of materials under tension and torsion, PhD thesis, Institute of Continuous Media Mechanics (2014). [19] Tretyakov, M.P., Wildemann, V.E., Lomakin, E.V., Failure of materials on the postcritical deformation stage at different types of the stress-strain state, Procedia Structural Integrity, 2 (2016) 3721-3726. DOI: 10.1016/j.prostr.2016.06.462. [20] Wildemann, V.E., Lomakin, E.V., Tretyakov M.P., Postcritical deformation of steels in plane stress state, Mechanics of Solids, 49(1) (2014) 18-26. DOI 10.3103/S0025654414010038. [21] Sokolkin, Y.V., Vildeman, V.E., Zaitsev, A.V., Rochev, I.N., Structural damage accumulation and stable postcritical deformation of composite materials, Mechanics of Composite Materials, 34(2) (1998) 171. [22] Ilinykh, A.V., Radionova, M.V., Vildeman, V.E., Computer synthesis and statistical analysis of the distribution of structural characteristics of granular composite materials, Composites: Mechanics, Computations, Applications, 2(2) (2011) 95. [23] Wildemann, V.E., Ilyinykh, A.V., Simulation of structural failure and scale effects of softening at the post-critical deformation stage in heterogeneous media, Physical Mesomechanics, 10(4) (2007) 23. [24] Tretyakova, T.V., Tretyakov, M.P., Wildemann, V.E. Estimate of measurements accuracy by using video-system of displacement and strain fields analysis, PNRPU Mechanics Bulletin, 2 (2011) 92-100. [25] Tretyakova, T.V., Wildemann, V.E., Spatial-time inhomogeneity of the processes of inelastic deformation of metals, Moscow, Fizmatlit, (2016). [26] Tetyakova, T.V., Wildemann, V.E., 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 Integrità Strutturale, 42 (2017) 303-314; DOI: 10.3221/IGF-ESIS.42.32 [27] Vildeman, V.E., Lomakin, E.V., Tret’yakova, T.V., Tret’yakov, M.P. Development of inhomogeneous fields under postcritical deformation of steel specimens in extension, Mechanics of Solids, 51(5) (2016) 612-618. DOI: 10.3103/S0025654416050150. N OMENCLATURE l 0 initial length of specimen test part d 0 initial diameter of specimen test part Δd changing of diameter of specimen test part at tension σ engineering stress σ B ultimate stress σ P the stress corresponding to the failure (or beginning of the unloading) at the postcritical deformation stage P B the load corresponding to the ultimate stress (or maximum load) P P the load corresponding to the failure (or beginning of the unloading) at the postcritical deformation stage ε longitudinal strain by DIC system ε yy strain along the coordinate y by DIC system y coordinate corresponding to the longitudinal axis of specimen z coordinate corresponding to the radial axis of specimen k P coefficient of the postcritical deformation stage realization