Issue 78

S. Vantadori et alii, Fracture and Structural Integrity, 78 (2026) 432-453; DOI: 10.3221/IGF-ESIS.78.25

0.2% y  , u  and

The obtained results exhibit minimal scatter, with the coefficients of variation calculated for

f  equal to

0.19%, 0.17%, and 0.72%, respectively. Fig. 6 presents a macrograph of the fracture surface, characterised by a V-shaped morphology. The fracture location is close to the centre of the gauge length.

600

500

400

300

200

STRESS [MPa]

100

0

0

4

8

12

16

APPARENT STRAIN [%]

Figure 5: Stress-strain curves under tensile loading.

Figure 6: Example of the fracture surface of a tested specimen under tensile loading.

S-N curve The cyclic tensile test results, in terms of applied stress amplitude, a  , and number of loading cycles to failure, f N , are presented in Tab. 2. SPECIMEN No. a  f N [MPa] [Cycles] 1 145 14302 2 145 18226 3 145 12370 4 65 48455 5 65 31010 6 65 40572 7 50 61206 8 50 81206 9 50 78336 10 40 46480 11 40 76480 12 40 48365 13 35 373685 14 35 350000 15 35 286420 16 29 1418755 17 29 1181120 18 29 1562030 19 27 Run-out 20 23 Run-out 21 19 Run-out 22 15 Run-out Table 2: Fatigue tensile results: stress amplitude, a  , and number of loading cycles to failure, f N .

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