PSI - Issue 41

Slobodanka Boljanović et al. / Procedia Structural Integrity 41 (2022) 704 – 711

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Slobodanka Bo ljanović et al. / Structural Integrity Procedia 00 (2019) 000 – 000

Table 1. Fatigue life evaluated for stress ratios equal to R = -1 and 0 and appropriate applied maximum stresses. Experiments are those by Grover et al. (1953). Relevant estimations are the present outcomes ( N est. ) and also those discussed by Boljanović and Carpinteri (2020, N est. *).

etl. * (cycles)

N est. (cycles)

N exp. (cycles) 30,000; 51,600 62,272; 129,807 70,000; 94,210 149,038; 173,076

S max (MPa)

R

N

310.70 240.79 342.55 273.62

-1 -1

27,710 59,850 38,680 76,250

26,910 58,090 37,600 76,150

0 0

Fig. 2. Fatigue strength analysis ( R = -1): (a) a vs. N and (b) b vs. N . Calculated curves generated within the present research.

Fig. 3. Fatigue strength analysis ( R = -1): (a) a vs. N and (b) b vs. N . Calculated curves generated within the present research.