Issue 68

C. Bleicher et alii, Frattura ed Integrità Strutturale, 68 (2024) 371-389; DOI: 10.3221/IGF-ESIS.68.25

the heat-affected zone according to SEP1240 [17]. [17] provides guidelines for the determination of cyclic material parameters with reference to specimen types, test boundary conditions, calibration standards for the test equipment and final evaluation of the results. To determine the elasto-plastic material behavior for higher total strains, ε a,t , lower test frequencies are necessary to enable a material relaxation. In this research project, the investigations were conducted with a test frequency of f = 0.1 to 25.0 Hz, according to [17].

Figure 2: I: axial fatigue specimens used for strain-controlled fatigue tests with K t = 1.04; I: axial fatigue specimens used for strain- and stress-controlled fatigue tests with K t = 1.00 comprising the welding filler, the heat affected zone and the base material called “integral material state”; III: removal position for the axial specimens in the welding filler, the heat affected zone and the base material; IV: bending specimen removed from the cast blocks; V: bending specimen removed from the component.

Figure 3: Left: X-ray film with specimens removed from the integral material state with pores; right: cross section of a failed specimens with a pore in the welding filler.

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