PSI - Issue 43

Stanislav Seitl et al. / Procedia Structural Integrity 43 (2023) 113–118 Author name / Structural Integrity Procedia 00 (2022) 000 – 000

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Fig. 4. Stress-strain curves for AISI 304 PL20-A.

Fig. 5. Stress-strain curves for AISI 304 PL10-A.

4. Discussion The experimental determination of Vickers hardness confirmed that it reflects depends material microstructure. This can be seen in case the case of PL20-E, where the material contains a lot of deformation twins due to straightening, see Fig. 1a). The mean value of HV 0.1 is 241, whereas in the case of PL10-E, where the amount of twins is lower is only 233, see Tab. 3. The tensile tests indicate that the strength properties of PL20-E material, Fig. 2, are inhomogeneous across the bar cross-section. The curves 01 and 02, characterizing the material near the bar surface exhibit higher strength than the curves describing the behaviour of the material inside the bar. Contrary to this, the material of PL-10 bar exhibits homogeneous properties, Fig. 3. As regards the tensile curves of PL20-A and PL10-A bars, they are the same within the experimental scatter, Fig. 4 and 5.

Fig. 6. The course of Vickers hardness along the cross-section of the PL20-E.bar. The different tensile strength properties on the surface and inside the PL20-E bar well correspond to differences in hardness. Fig. 6 shows the evolution of hardness across the bar. The highest values 250 and 312 were measured on