PSI - Issue 28

ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceD rect Available online at www.sciencedirect.com ScienceDirect

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

Procedia Structural Integrity 28 (2020) 2086–2098

© 2020 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 European Structural Integrity Society (ESIS) ExCo Abstract A possible version of a model describing degradation of initial strength properties of structural alloys affected by fatigue and creep is introduced, based on the modern viewpoint of mechanics of damaged media (MDM). Processes of viscoplastic deformation and damager accumulation in structural alloys are analyzed using numerical modeling. Special attention is paid to the issues of modeling the processes of viscoplastic deformation and damage accumulation for complex deformation processes accompanied by the rotation of main sites of stress and strain tensors. New qualitative and quantitative features of the failure process are noted, which are connected with stressed-strained state history, damage degree, stress relaxation and other factors. © 2020 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 European Structural Integrity Society (ESIS) ExCo Keywords: Modeling; mechanics of damaged media; complex deformation; fatigue life; sustained strength; failure; service life. 1. Introduction The development of structures and devices of modern power engineering, aircraft manufacturing, etc. characterized by an increase in their operating parameters, reduction of metal consumption due to the rational design and application of new structural materials, a significant increase in the weight of non-stationary modes of cyclic thermal loading, a significant extension of temperature range of the engineering designs. These trends have led to what is currently one of the main objectives of design of structures and machines of new technology is the solution to the problem of estimating reliable resource newly designed apparatus, developed diagnostics and prognostication of individual 1st Virtual European Conference on Fracture Defining relations of mechanics of damaged media effected by fatigue and creep L.A. Igumnov a *, I.A. Volkov a a Research Institute for Mechanics, National Research Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue 23, Nizhny Novgorod, 603950, Russia Abstract A possible version of a model describing degradation of initial strength properties of structural alloys affected by fatigue and creep is introduced, based on the mo rn viewpoint of mechanics of dama ed media (MDM). Processes of viscoplastic deform tion and damager accumulati in structural alloys are analyzed using numerical modeling. Special attention is paid to the issues of modeli g the processes of viscoplastic deformation and damage accumulation f r complex deformation processes accompanied by the rotation of main sites f stress and str in tensors. New qu litative and quantitative features of the failur process are not , which are c nected with stressed- tr ined state hi t ry, damage degre , stress relax tion and other factors. © 2020 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 European Structural Integri y So i ty (ESIS) ExCo Keywords: Modeling; mechanics of damaged media; complex deformation; fatigue life; sustained strength; failure; service life. 1. Introduction The development of structures and devices of modern power engineering, aircraft manufacturing, etc. characterized by an increase in their operating p rameters, reduction of metal consumption due to he rational design and pplication of new st uctural materials, a significant inc ase n the w ight f non-stationary modes of cyclic thermal loading, a sig ificant extension of temperature r ge of the e gin erin desig s. These trends have led to what is currently one of the main objectives of design of structures and mach es of new technology is th solution to the p oblem of estimating reliable r ource newly designed apparatus, d veloped diagnostics and prognostica i n of individual 1st Virtual European Conference on Fracture Defining relations of mechanics of damaged media effected by fatigue and creep L.A. Igumnov a *, I.A. Volkov a a Research Institute for Mechanics, National Research Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue 23, Nizhny Novgorod, 603950, Russia

* Corresponding author. Tel.: Tel.: +7-831-465-7655; fax: +7-831-465-6611. E-mail address: igumnov@mech.unn.ru * Corresponding author. Tel.: Tel.: +7-831-465-7655; fax: +7-831-465-6611. E-mail address: igumnov@mech.unn.ru

2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo 2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo

2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.11.034