PSI - Issue 60

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 60 (2024) 3–12

© 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 Abstract A novel methodology is proposed for evaluating the stress-strain curve and determining the Ramberg-Osgood parameters (n, α) of SS316LN material. This involves utilizing load-displacement data from various specimen types, including both smooth and notched tensile specimens with different notch radii, in conjunction with finite element analysis . An error minimization method was used for evaluating the material parameters. The proposed approach for the evaluation of unique Ramberg-Osgood parameters provides a better result than that of the material stress-strain data of smooth specimen test. Ramberg-Osgood parameters were evaluated at two temperatures, i.e., 25°C and 650°C and compared with RCC MRx code. Stress-strain equation as provided in the RCC-MR, can’t be used in FE analysis if the plastic strain exceeds 1.5% at certain regions of structure containing discontinuity, e.g., regions like shell-nozzle junction, vessel head, T-junction etc. The approach developed in this work shall help to obtain the material stress-strain curve over a wide range of plastic strain values. Ramberg-Osgood parameters were evaluated for the whole temperature range of 25°C and 650°C, which can be used for structural integrity analysis of reactor components made of stainless steel grade SS316LN. The range of applicability of data for RCC-MR code was extended beyond 1.5% of plastic strain in this work. The equations derived in this work shall be useful for structural integrity analysis and life assessment of structural components of nuclear reactors . © 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 Keywords: Ramberg-Osgood parameters, RCC-MR, Stress-Strain data, SS316LN; Third International Conference on Structural Integrity 2023 (ICONS 2023) A new approach to evaluate Ramberg-Osgood parameters for SS316LN using different types of specimens S. K.Pandey a,b* , M.K.Samal a,c , Sajish S.D b a Division of Engineering Sciences, Homi Bhabha National Institute, Mumbai, India. b Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu, India (pandey@igcar.gov.in). c Reactor Safety Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India (mksamal@barc.gov.in). * Corresponding Author

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 10.1016/j.prostr.2024.05.026