PSI - Issue 33

M.P. Tretyakov et al. / Procedia Structural Integrity 33 (2021) 871–877 Author name / Structural Integrity Procedia 00 (2019) 000–000

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a

b

Fig. 5. Fields of distribution of equivalent stresses (a) and equivalent deformations (b) after calculation for point 9 (Table 3).

Fig. 6. Dependence of conditional stresses on displacement along the x-axis: 1 - experimental data; 2 - a sample of the original geometry; 3 - sample with a narrowing of the working part.

Fig. 7. Sample shape in an undeformed state (transparent contour) and after stretching (blue contour).

All the diagrams obtained are in good agreement at the stage of elastic deformation and hardening, when the point corresponding to the maximum load on the sample is reached, when solving numerical problems, a decrease in the maximum achieved stresses is observed in relation to the experimental data. This difference increases at the initial stage of postcritical deformation (up to elongation u x = 1.25 mm), and is minimized at the maximum degree of postcritical deformation (u x = 2.17 mm). The deformation diagram for a specimen with an initial narrowing of the working part is located below the diagram for a specimen with a smooth working part. The shape of the sample with a neck obtained as a result of modeling qualitatively corresponds to the shape of the sample after the experiment for uniaxial tension. The problem of tension of a steel specimen considered in this work makes it possible to simulate the processes of localization of deformations in the form of a neck in a specimen at the postcritical stage of deformation.