PSI - Issue 40

ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000 Structural Integrity Procedia 00 (2022) 000 – 000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com Sci nceDire t Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 40 (2022) 348–353

© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the15th International Conference on Mechanics, Resources and Diagnostics of Materials and Structures. Abstract To describe the creep rupture process under the complex stress, various equivalent stresses have been considered. From them, the equivalent stress has been selected, at which the total error of the difference between the experimental and theoretical values takes the smallest value among the considered equivalent stresses. Three basic equivalent stresses have been considered, as well as two complex equivalent stresses, which are a linear combination of two basic ones with one material parameter. The analysis of the total errors in the considered experimental data has showed that with the simultaneous effect of internal pressure and axial force on the wall of tubular specimen (or biaxial tension of a plane element), an complex equivalent stress should be used in the form of a combination of the maximum normal stress and the Mises stress. At simultaneous torsion and tension of tubular specimen (or simultaneous tension and compression of a plane element), an complex equivalent stress should be used in the form of a combination of the maximum normal stress and the doubled maximum tangential stress. © 2022 The Authors. Publish ed by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the15th International Conference on Mechanics, Resource and Diagnostics of Materials and Structures. Keywords: Creep rupture; rupture time; plane stress state, equivalent stress. 1. Introduction The kinetic approach Lokoshchenko et al. (2005) and the criterion approach Lokoshchenko et al. (2004) are used for describing the creep rupture under complex stress. The works in which experimental data had been obtained at 15th International Conference on Mechanics, Resource and Diagnostics of Materials and Stru tures Choice of complex equivalent stress for two different variants of the plane stress state Vladlen Nazarov* Institute of Mechanics Lomonosov Moscow State University, 1 Michurinsky Avenue, Moscow, 119192, Russian Federation Abstract To describe the creep rupture process under the complex stress, various equivalent stresses have been considered. From them, the equivalent s r ss has been s lected, at whic the total error of the diff rence betwe n the experimental and theo etical values takes th smalle t valu among the considered equivalent st esses. Thre basic equivalent str ss s have bee consid red, as w ll as two co plex equivalent stresses, which are a line r combination of two basic ones wi h one material parameter. The analysis of he total errors in the con ider d experiment l dat has showed that with the simultaneous effect of intern l pr ssure and axial force on the wall of ubular p cim n (o biaxi tension of a plane element), an complex equivalent stress should be used in the m f a combination of the maximum normal stress and the Mis s stress. At simultaneous torsion and tension of tubular specimen (or simultaneous tension and compression of a plane element), an complex eq ival nt tres shoul b u ed in the form of a combination of th maximum normal stres and the doubl d maximum tangential stress. © 2022 The Auth rs. Publish ed by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der responsibility of scientific committe of the15th International C ference on Mechanics, Resource and Diagnostics of Materials and S ructur s. Keywords: Creep rupture; rupture time; plane stress state, equivalent stress. 1. Introduction The kinetic approach Lokoshchenko et al. (2005) and the criterion approach Lokoshchenko et al. (2004) are used for descr bing the creep rupture under complex stress. The works i which experimental data had been obtained at 15th International Conference on Mechanics, Resource and Diagnostics of Materials and Structures Choice of complex equivalent stress for two different variants of the plane stress state Vladlen Nazarov* Institute of Mechanics Lomonosov Moscow State University, 1 Michurinsky Avenue, Moscow, 119192, Russian Federation

* Corresponding author. Tel.: +7-999-916-2036; fax: +7-999-916-2036. E-mail address: inmec130@mail.ru * Corresponding author. Tel.: +7-999-916-2036; fax: +7-999-916-2036. E-mail address: inmec130@mail.ru

2452-3216 © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the15th International Conference on Mechanics, Resource and Diagnostics of Materials and Structures. 2452-3216 © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der responsibility of t scientific committe of the15th Int rnational C ference o Mechanics, Resource and Diagnostics of Materials and Structures.

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the15th International Conference on Mechanics, Resources and Diagnostics

of Materials and Structures. 10.1016/j.prostr.2022.04.046