Issue 75

O. Neimark et alii, Fracture and Structural Integrity, 75 (20YY) 250-264; DOI: 10.3221/IGF-ESIS.75.18

1. The formation of the structure during shock-wave treatment is determined by the self-similar regularities of the elastic-plastic wave profile, which can be identified by introducing an "action invariant" that links the shock wave parameters (amplitude, wave front width) with the dissipative properties of the material caused by defects (stored energy). 2. The introduction of an "action invariant" enables describing the kinetics of fatigue crack development in the materials subjected to preliminary shock-wave loads, including the initiation and development of small cracks, the Paris cracks. 3. The quantitative fractographic analysis using the interferometry data for fracture surfaces made it possible to identify structural scales for determining the "action invariants" that determine the kinetics of fatigue crack in materials after shock-wave treatment. 4. Methodological principles for studying the behavior of materials under consecutive shock-wave and fatigue loads have been developed, allowing for optimization of shock-wave treatment to ensure fatigue life. 5. With regard to LSP of materials in aircraft engine construction, it is necessary to implement a full experimental and research cycle that includes stages such as - conducting experiments with plane-wave loading of targets to determine the values of the "action invariant" of structured wave fronts at different wave pulse amplitudes and obtaining standard samples for fatigue testing; - conducting fatigue tests on standard samples in combination with structural analysis methods to determine the "action invariants" related to the kinetics of fatigue crack; - substantiation of models to describe shock-wave fronts in the characteristic ranges of LSP treatment, followed by an experimental study of the effect of this treatment for model LSP settings. 6. Development of optimization algorithms using "action invariants". The listed items represent the directions of detailed research into the characteristics of shock-wave loading and its relationship with fatigue life assessment using the concept of action invariants, including LSP treatment

A UTHOR CONTRIBUTION

A T

uthor contributions are following. Conceptualization and supervision: O.B.N. (Oleg B. Naimark); methodology A.N.B (Aleksandr N. Balakhnin), M.V.B. (Mikhail V. Bannikov), V.A.O. (Vladimir A. Oborin), S.V.U. (Sergey V. Uvarov), A.D.Yu. (Aleksandra D. Yurina) ; writing-original draft preparation: O.B.N., V.A.O., M.V.B.

A CKNOWLEDGEMENTS

he work was carried out as part of a major scientific project funded by the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2024-535 dated 23 April 2024).

R EFERENCES

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