Issue 51

A. S. Yankin et alii, Frattura ed Integrità Strutturale, 51 (2020) 151-163; DOI: 10.3221/IGF-ESIS.51.12 151 Influence of static mean stresses on the fatigue behavior of 2024 aluminum alloy under multiaxial loading A.S. Yankin, V.E. Wildemann, N.S. Belonogov, O.A. Staroverov Center of Experimental Mechanics, Perm National Research Polytechnic University, Perm, Russian Federation yas.cem@yandex.ru, https://orcid.org/0000-0002-0895-4912 wildemann@pstu.ru , https://orcid.org/0000-0002-6240-4022 cem.belonogov@gmail.com cem_staroverov@mail.ru , https://orcid.org/0000-0001-6095-0962 A BSTRACT . Axial alternating stress controlled fatigue tests with superimposed static torsional mean stress and shear alternating fatigue tests with superimposed static tensile mean stress are represented. The material used in the current experimental investigation is 2024 aluminum alloy. A decrease in the fatigue life of the material was observed with an increase in the shear and static tensile stresses. Marin and modified Crossland methods are analyzed by means of the available experimental data. The two modifications of Sines method are proposed to take into account the static torsional stress effect (Sines+) and different slopes of the S-N curves in tension-compression and torsion tests (Sines++). It is shown that Sines++ model is the most accurate among others. K EYWORDS . Multiaxial fatigue; Mean stress; Multiaxial fatigue criteria; 2024 aluminum alloy. Citation: Yankin, A.S., Wildemann, V.E., Belonogov, N.S., Staroverov, O.A., Influence of static mean stresses on the fatigue behavior of 2024 aluminum alloy under multiaxial loading, Frattura ed Integrità Strutturale, 51 (2020) 151-163. Received: 30.09.2019 Accepted: 07.11.2019 Published: 01.01.2020 Copyright: © 2020 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. I NTRODUCTION uring operations the greatest number of critical components of construction elements undertake complex cyclic loadings, thus the estimation of their influence on durability of metal materials is a problem to be solved [1-5]. Also, the need in studying fatigue processes under complex stress state brought a number of experimental works in this area, which used specialized equipment and methods of multiaxial loading. Here are some major research centers studying the problems of multiaxial fatigue: ENSAM University in Bordeaux, France (T. Palin-Luc, N. Saintier, F. Morel) [6, 7], University of Opole, Poland (T. Lagoda) [8], University of Sheffield, United Kingdom (L. Sumsel) [9], University of Lisbon, Portugal (V. Anes, L. Reis, M de Freitas) [10, 11], S.P. Timoshenko Institute of Mechanics, Kiev, Ukraine (V.P. Golub) [12], Ishlinsky Institute for Problems in Mechanics RAS, Moscow, Russia (N.G. Burago, A.B. Zhuravlev, I.S. Nikitin) [13, 14], and others [15]. D