PSI - Issue 42

D. Kosov et al. / Procedia Structural Integrity 42 (2022) 545–552 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

548 4

Fig. 1. (a) Test equipment; (b) smooth specimen

Table 1. Main mechanical properties of aluminum alloy 2024. Material E (GPa) σ 0 (MPa) n

γ

R inf 300

Al-alloy 2024

118.0

430

6.25

15.5

Fig. 2. Diagram of uniaxial tension of aluminum alloy 2024.

The resulting diagram was approximated by the exponential (1) and power law (2). Fig. 2 shows the difference between the true deformation diagram and the approximating functions. It was found that for the material aluminum alloy 2024 it is preferable to use the exponential law of isotropic hardening. 3.2. Testing hollow cylindrical specimens with notch The object of the second stage of experimental studies was a hollow cylindrical specimen with notch (Fig. 3b). The thickness of the cylinder wall in a smooth specimen and in the minimum section of the specimen with a notch was t=1mm. The tests were carried out on the Bi-00-701 Axial-Torsion Test System (Fig. 3a), which can be loaded with axial forces, torque, internal pressure, as well as their various combinations. In tensile and compression tests, an axial extensometer was used. A transverse extensometer was used to measure the circumferential strains in the internal