PSI- Issue 9

Yu. Matvienko et al. / Procedia Structural Integrity 9 (2018) 16–21 Author name / Structural Integrity Procedia 00 (2018) 000–000

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benefit of the crack compliance technique resides in a posteriori character of the experimental procedure. This means that crack length measurements and further determination of fracture mechanics parameters are performed after cyclic loading with a high degree of accuracy. The second advantage resides in quantitative determination of fracture mechanics parameters for cracks of different lengths at different stages of cyclic loading. These data can be obtained for the pure residual stress field as well for combined influence of internal and external stresses. Experimental information, if necessary, may be supplemented by data obtained for different remote stress levels to reveal a possible influence of non-linear effects. The obtained results show how a relaxation of residual stresses due to cyclic loading influences on a redistribution of fracture mechanics parameters.

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Fig. 5. SIF (a) and T-stress (b) values as a function of the loading cycle number

Acknowledgements The authors acknowledge the support of the Russian Science Foundation (project N 18-19-00351). References McLung, R., 2007. A literature survey on the stability and significance of residual stresses during fatigue. Fatigue & Fract. Engng. Mater. & Struct. 30, 173–205. Pisarev, V., Matvienko, Yu., Eleonsky, S., Odintsev, I., 2017. Combining the crack compliance method and speckle interferometry data for determination of stress intensity factors and T-stresses. Engineering Fracture Mechanics 179, 348-374. Reid, L., 2014. Hole Cold Expansion – The Fatigue Mitigation Game Changer of the Past 50 Years. Advanced Materials Research 891–892, 679– 684. Schmidt, H., 2005. Damage tolerance technology for current and future aircraft structures, proceedings of the 23 rd ICAF Symposium of the international Committee on Aeronautical Fatigue 1, 1–41.