Issue 47

Yu. G. Matvienko et alii, Frattura ed Integrità Strutturale, 47 (2019) 303-320; DOI: 10.3221/IGF-ESIS.47.23 303 Fracture and Structural Integrity: ten years of ‘Frattura ed Integrità Strutturale’ The effect of low-cycle fatigue on evolution of fracture mechanics parameters in residual stress field caused by cold hole expansion Yu. G. Matvienko Mechanical Engineering Research Institute of the Russian Academy of Science (IMASH RAN). 4 M. Kharitonievsky Per., 101990 Moscow, Russia matvienko7@yahoo.com. V.S. Pisarev, S. I. Eleonsky Central Aero-Hydrodynamics Institute named after Prof. N.E. Zhukovsky (TsAGI). 1 Zhukovsky Street, Zhukovsky 140180 Moscow Region, Russia. VSP5335@mail.ru, https://orcid.org/0000-0002-5378-609X juzzepka@mail.ru , https://orcid.org/0000-0003-4345-067X A BSTRACT . Localized displacement measurements based on electronic speckle-pattern interferometry are used to obtain crack mouth opening displacement (CMOD), stress intensity factor (SIF) and T-stress values during crack growth around cold-expanded holes. The specimens with a central open hole are made from 2024 aluminium alloy. The expansion level is 5% of nominal interference. The results are obtained for the same stress range   = 350 MPa, but different stress ratio R = –0.4 and R = –1.0. A sequence of narrow notches, inserted under the constant external load, serves for crack modelling at different stages of cyclic loading. Initial experimental data represent in-plane displacement component values measured in the vicinity of the crack tip. The transition from in-plane displacement components to SIF and T-stress values follows from the relationships of modified version of the crack compliance method. The crack length curves of CMOD, SIF and T- stress profiles are obtained for different stages of cyclic loading. These data provide the construction of dependencies of fracture mechanics parameters for cracks of fixed lengths from the loading cycle number. K EYWORDS . Cold expansion; Crack growth; Crack mouth opening displacement; Stress intensity factor; T-stress. Citation: Matvienko, Yu. G., Pisarev, V. S., Eleonsky, S. I., The effect of low-cycle fatigue on evolution of fracture mechanics parameters in residual stress field caused by cold hole expansion, Frattura ed Integrità Strutturale, 47 (2019) 303-320. Received: 11.09.2018 Accepted: 29.11.2018 Published: 01.01.2019 Copyright: © 2019 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.