PSI - Issue 66

María Moreno-Rubio et al. / Procedia Structural Integrity 66 (2024) 362–369 Author name / Structural Integrity Procedia 00 (2025) 000 – 000

366

5

Table 5. Results of simple fatigue test at HT

Test number

R

f (Hz)

σ max (MPa)

N f (Cycles) 6800 6242 54469 11278 9857 155763 271480 N f (Cycles) 4680 8502 17321 26173 32564 53556 110680 166148 4.30E6 5.00E6

1 2 3 4 5 6 7

0.1 0.1 0.1 0.1 0.1 0.1 0.1

10 10 10 10 10 10 10

1094 1050 1000 1000 1000 900 831

Table 6. Results of fretting fatigue test at HT

Test number

R

f (Hz) N

σ max (MPa)

(kN)

1 2 3 4 5 6 7 8 9

0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

8 8 8 8 8 8 8 8 8 8

10 10 10 10 10 10 10 10 10 10

1000 900 750 650 575 500 450 400 350 350

10

Fig. 2. Simple fatigue and fretting fatigue test at RT and HT (650ºC)

3. Life prediction model There are various fatigue life prediction models. Some focus on the initiation phase, as used by Szolwinski (1996), others on the propagation phase, as applied by Navarro et al. (2014), while some employ a combination of both initiation and propagation phases, as used by Navarro et al. (2011). In this work, we will employ the combined phase model, which involves analyzing each phase separately, without predefining when one phase ends and the