Issue 42

R. Pawliczek et alii, Frattura ed Integrità Strutturale, 42 (2017) 30-39; DOI: 10.3221/IGF-ESIS.42.04 37 the last block enlarged the area of the hysteresis loop and a little shift of the hysteresis loop after 3000 load cycles is observed. At the same time, the mean load ε m =0.2% was recorded that remained after the strain (curves 5 and 6 in Fig. 5). The maximum strain of ε max =0.5% and the mean strain ε m(max)= 0.15% were recorded. R ESULTS OF CALCULATIONS or registered histories of the strains the proposed algorithm and two kinematic models (Garud-Mroz and Chu) of cyclic deformation were used to calculate the stress history parameters: stress amplitude and mean stress value in this case. Figs. 9 and 10 presents hysteresis loops as stress-strain relationship calculated by the use of Garud-Mroz model. Form of the graphs corresponds to the measurement results presented in Fig. 8 and Fig.9, respectively. Figure 9 : Stress-strain loops at the increasing mean load value calculated with the use of Garud-Mroz model. Figure 10 : Stress-strain loops at the decreasing mean load value calculated with the use of Garud-Mroz model. -0.004 0 0.004 0.008  -400 -300 -200 -100 0 100 200 300 400  MPa 1 2 3 4 5, 6 1: N=2000; 2: N=5000 3: N=7000; 4: N=10000 5: N=12000; 6: N=15000 -0.004 0 0.004 0.008  -400 -300 -200 -100 0 100 200 300 400 500  MPa 5,6 3,4 2 1 1: N=2000; 2: N=5000 3: N=7000; 4: N=10000 5: N=12000; 6: N=15000 F