PSI - Issue 2_B

Vladimir Oborin et al. / Procedia Structural Integrity 2 (2016) 1063–1070 Author name / Structural Integrity Procedia 00 (2016) 000–000

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required to achieve a significant total effect. Obviously, in steels of the well-expressed aluminum–magnesium system, magnesium diffusion can be a factor efficiently controlling effects of filling up the discontinuities.

5. Conclusion The comparative analysis of the scaling characteristics of samples loaded under conditions of high - and gigacycle fatigue shows a significant decrease in the range of spatial scales, where the Hurst exponent remains constant for dynamically loaded samples in the «fish-eye» (0.5-10.9 mkm) zone. This result confirms our assumption that mentioned characteristic scales L pz and l sc play an important role in the list of variables for the kinetic equation fatigue of crack growth and can be used for the identification of phenomenological parameters (power index) providing self-similar law for the crack path by Oborin and Naimark (2014). Acknowledgements This study was supported by the Russian Science Foundation, project № 14-19-01173. References Mandelbrot, B.B., 1983. The fractal geometry of nature. N.Y.: W.H. Freeman, New York, pp.480. Peters J. O., 2000. Influence of foreign object damage on crack initiation and early crack growth during high-cycle fatigue of Ti-6Al-4V. Eng. Fract. Mech. 67, 193–207. Paris P., Lados D., Tad H., 2008. Reflections on identifying the real  K effective in the threshold region and beyond. Engineering Fracture Mechanics 75, 299–305. Barenblatt G.I., 2006. Scaling phenomena in fatigue and fracture. Int.J. of Fracture 138, 19–35. Ritchie R.O., 2005. Incomplete self-similarity and fatigue-crack growth. Int.J. of Fracture 132, 197–203. Bouchaud E., 1997. Scaling properties of cracks. J. Phys. Condens. Matter 9, 4319–4344. Froustey C., Naimark O., Bannikov M., Oborin V., 2010. Microstructure scaling properties and fatigue resistance of pre-strained aluminium alloys (part 1: Al-Cu alloy). European Journal of Mechanics A/Solids 29, 1008–1014. Shanyavskiy A.A., 2013. Mechanisms and modeling of subsurface fatigue cracking in metals. Engineering Fracture Mechanics 110, 350–363. Oborin V., Naimark O., 2014. Scaling Invariance of Fatigue Crack Growth in Aluminum Alloy. Procedia Materials Science 3, 1004–1008.