PSI - Issue 60

ScienceDirect StructuralIntegrity Procedia 00 (2023) 000 – 000 StructuralIntegrity Procedia 00 (2023) 000 – 000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect

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Procedia Structural Integrity 60 (2024) 494–509

© 2024 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 ICONS 2023 Organizers © 2024 The Authors. Published by ELSEVIER B.V. Peer-review under responsibility of the ICONS 2023 Organizers Abstract Deformation of metallic materials at elevated temperatures occurs by the movement of atoms either individually or in a group by diffusion, grain boundary sliding, and the slip processes as facilitated by vacancy, dislocations, and grain boundaries. The constitutive relationship for deformation is developed based on the contributions of external test conditions like temperature and strain rate or stress applied and the internal conditions like chemical composition, phases present, and the length scale of microstructures. Deformation can occur coherently by synergisms of all participating mechanisms, failing to which becomes a source for initiating the damage in the material. The same mechanisms that were initially responsible for deformation to occur then become the facilitators for void nucleation and its growth, which then go through cavity coalescence, and crack formation on the way to cause ultimate fracture of materials. The constitutive relationships for damage mechanisms then take the form that promotes the removal of atoms from the damaged part to a farther site, which further enhances the act of material damage. In the present work, the micro-mechanisms responsible for deformation and failure will be examined to evolve a relationship towards establishing connectivity between these two processes by integrating the effects of internal and external variables for a range of materials. © 2024 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 ICONS 2023 Organizers Third International Conference on Structural Integrity 2023 (ICONS 2023) Micro-Mechanism Relations Between Deformation and Damage Behavior of Materials at Elevated Temperature B.P. Kashyap a *, Kuldeep Singh a Abstract Deformation of metallic materials at elevated temperatures occurs by the movement of atoms either individually or in a group by diffusion, grain boundary sliding, and the slip processes as facilitated by vacancy, dislocations, and grain boundaries. The constitutive relationship for deformation is developed based on the contributions of external test conditions like temperature and strain rate or stress applied and the internal conditions like chemical composition, phases present, and the length scale of microstructures. Deformation can occur coherently by synergisms of all participating mechanisms, failing to which becomes a source for initiating the damage in the material. The same mechanisms that were initially responsible for deformation to occur then become the facilitators for void nucleation and its growth, which then go through cavity coalescence, and crack formation on the way to cause ultimate fracture of materials. The constitutive relationships for damage mechanisms then take the form that promotes the removal of atoms from the damaged part to a farther site, which further enhances the act of material damage. In the present work, the micro-mechanisms responsible for deformation and failure will be examined to evolve a relationship towards establishing connectivity between these two processes by integrating the effects of internal and external variables for a range of materials. Third International Conference on Structural Integrity 2023 (ICONS 2023) Micro-Mechanism Relations Between Deformation and Damage Behavior of Materials at Elevated Temperature B.P. Kashyap a *, Kuldeep Singh a a Department of Metallurgical and Materials Engineering, Indian Institute of Technology Jodhpur, Karwar, Jodhpur,342030, India a Department of Metallurgical and Materials Engineering, Indian Institute of Technology Jodhpur, Karwar, Jodhpur,342030, India Keywords: Cavitation; constitutive relationship; high temperature deformation; microstructure effects Keywords: Cavitation; constitutive relationship; high temperature deformation; microstructure effects 1. Introduction Grain boundaries in polycrystalline materials play a role of resistance to deformation at low temperature, but the same become facilitator to deformation at elevated temperature. The volume fraction of grain boundaries in polycrystalline materials rapidly increases with a decrease in grain size below ~ 10 μm and even more so when the grain size reaches a nanocrystalline level (Kim et al., 2000). 1. Introduction Grain boundaries in polycrystalline materials play a role of resistance to deformation at low temperature, but the same become facilitator to deformation at elevated temperature. The volume fraction of grain boundaries in polycrystalline materials rapidly increases with a decrease in grain size below ~ 10 μm and even more so when the grain size reaches a nanocrystalline level (Kim et al., 2000).

* Corresponding author. Tel.: +91 291-2801553 E-mail address: bpk@iitj.ac.in * Corresponding author. Tel.: +91 291-2801553 E-mail address: bpk@iitj.ac.in

2452-3216 © 2024 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 ICONS 2023 Organizers 10.1016/j.prostr.2024.05.069 2452-3216© 2024 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 ICONS 2023 Organizers 2452-3216© 2024 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 ICONS 2023 Organizers