PSI - Issue 59

Bernadett Spisák et al. / Procedia Structural Integrity 59 (2024) 3–10 B. Spisa ´ k et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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the finite element analysis in all cases. Furthermore, the higher the a/W value, the larger the range of variation, which is more pronounced for specimens of size 0.5T, 0.25T and 0.16T. For 0.6 a/W , the differences are in the range of only 0.08%, while for 0.8 a/W , this value increases to 0.29%. Similar trends were found for specimens of 1T, 0.25T and 0.16T.

Fig. 6. Percentage deviation of stress intensity factors determined by formula and simulation for hybrid specimen.

However, it can be concluded that these values are negligible differences, making the formula well suited for the determination of the stress intensity factor for the hybrid CT specimen, which allows the determination of K value for a given force without the need for finite element simulation. 4. Summary In this paper, a new type of fracture mechanics test specimen, not previously reported in the literature, is presented that is suitable for stress corrosion crack propagation studies and incorporates the advantages of CT and DCB designs. It also allows easy pre-cracking and pre-loading of the specimen. In order to simplify specimen pre loading, the formula for the stress intensity factor for the specimen has been determined for aspect ratios between 1T and 0,16T and for ratios 0.6 to 0.8, a/W . The new geometry is planned to be used for stress corrosion cracking testing where the specimens will be placed in the pressurized capsules of the autoclave built by VEIKI Energia+ Energetikai Fejleszt ő , Kivitelez ő Kft. References BS 7910:2019: Guide to methods for assessing the acceptability of flaws in metallic structures. ISO 7539-6:2018: Corrosion of metals and alloys stress corrosion testing part 6: Preparation and use of precracked specimens for tests under constant load or constant displacement. Murakami, Y., 1990. Stress intensity factors handbook. Pergamon Oxford Tada H., Paris, P.C., Irwin, G.R., 2000. The Stress Analysis of Cracks Handbook. 3rd Edition, ASME Press, New York.