PSI - Issue 68

Robert Szlosarek et al. / Procedia Structural Integrity 68 (2025) 1173–1180 Robert Szlosarek et al. / Structural Integrity Procedia 00 (2025) 000–000

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Fig. 2. After the first cycle, the damage value of the cycle was calculated as the inverse of the lifetime ∆ = 6 3 ! . (4) With this damage value the parameters ′ and ′ are updated and a new maximum stress is calculated. Now, the lifetime calculation is performed again and the procedure repeats. This will be done until the damage reaches the value one. The number of repetitions is counted and the total number is equal to the computed lifetime.

Fig. 2. scheme of the computational framework.

3. Results The suggested procedure was utilized on two experimental data sets. Both are from a novel copper-alloyed metastable austenitic stainless steel X2CrNiCuN17-6-4. The effect of copper addition is described by Hauser et al. (2023). Nitzsche et al. (2024) present the behavior of this material under quasi-static and cyclic loading. Here, the data for the fatigue tests of the casted as well as casted and subsequently swaged and revision annealed material will be used. Hence, the data of Fig. 3 are taken out of Nitzsche et al. (2024). Fig. 3 shows the load cycles to failure depending on the total strain amplitude. The figure shows the experimental results (markers) as well as the numerical results (lines) obtained by the parameters determined at half of the lifetime and taken out of Nitzsche et al. (2024).