PSI - Issue 38

Benaouda Abdellaoui et al. / Procedia Structural Integrity 38 (2022) 116–131 Benaouda Abdellaoui et al / Structural Integrity Procedia 00 (2021) 000 – 000

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4.2.1. Test result The results of the fatigue tests are given in Table 5

Table 5. Results of strain-controlled tests.

half life

Number of cycle at failure

E (MPa), 1 st cycle

Comment 4

reference

 max ()

 / 2 (MPa) 5

 t / 2 (%)

 e / 2 (%)  p / 2 (%)

P2F12 P3F13 P4F12 P3F19 P3F11 P2F18 P4F11 P2F13 P3F18 P3F12 P2F16 P3F16 P4F19 P3F17 P4F17

198 949 199 595 197 412 200 134 199 770 199 999 196 228 200 406 201 831 199 322 197 496 199 799 195 246 202 460 197 624

1

0.450 0.315 0.315 0.293 0.293 0.293 0.270 0.270 0.270 0.248 0.248 0.248 0.225 0.203 0.180

851 623 620 582 580 581 528 533 541 491 486 487 438 408 354

0.428 0.312 0.314 0.291

0.022 0.003 0.001 0.002 0.002 0.002 0.001 0.004 0.002 0.001 0.002 0.004 0.001 0.001 0.001

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IT Failure IT Failure IT Failure ET Failure IT Failure ET Failure IT Failure IT Failure IT Failure ET Failure ET Failure STO Failure

0.7 0.7

10 450

8 685

0.65 0.65 0.65

12 573 18 737 14 138 38 513 19 467 17 148 16 471 18 789 162 495 727 775 8 550

0.29 0.29

0.6 0.6 0.6

0.269 0.266 0.268 0.246 0.246 0.244 0.224 0.201 0.179

0.55 0.55 0.55

0.5

Failure Failure

0.45

1 000 000

Not failure

0.4

Fig. 5. Stress amplitude graph - lifecycle - R = 0.1

4 IT : interior cracking; ET : exterior cracking, STO : opposite of extensometer knives 5 stress amplitude for half-life (N) with = / 0 , S 0 initial section

(2)