PSI - Issue 35

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ScienceDirect

Procedia Structural Integrity 35 (2022) 254–260

© 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya Abstract Hydrogen embrittlement is a phenomenon that affects the mechanical properties of steels intended for hydrogen transportation. One affected by this embrittlement is the Ductile to Brittle Transition Temperature (DBTT), which characterizes the change in the failure mode of the steel from ductile to brittle. This temperature is conventionally defined and compared to the operating temperature as an acceptability criterion for codes. Transition temperature does not depend only on the material, but also on specimen geometry particularly the thickness. Generally, the transition temperature is defined for the conservative reason by Charpy impact test. Standard Charpy specimens are straight beams with a thickness of 10 mm. For thin pipes, it is impossible to extract these standard specimens. One uses in this case Mini-Charpy specimens with a reduced thickness due to pipe curvature. This paper aims to quantify the effect of hydrogen embrittlement on the transition temperature of pipe steel (API 5L X65) using two types of Charpy specimens. © 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya Keywords: Hydrogen embrittlement; Pipe steel; Ductile and brittle Transition Temperature; Charpy impact test; API 5L X65. ittl t i t t t t i l ti t l i t t t ti . t t i ittl t i t til t ittl iti t , i t i t i t il t t l til t ittl . i t t i ti ll i t t ti t t t ilit it i . iti t t t l t t i l, t l i t ti l l t t i . ll , t t iti t t i i t ti i t t t. t i t i t it t i . t i i , it i i i l t t t t t i . i t i i i i it t i t i t . i i t ti t t ittl t t t iti t t i t l i t t i . © t . li . . This i ti l t li tt :// ti . /li / / . i i ilit i , l i : r rittl t; i t l; til rittl r iti r t r ; r i t t t; I . 2nd International Workshop on Plasticity, Damage and Fracture of Engineering Materials Safety margin on the ductile to brittle transition temperature after hydrogen embrittlement on X65 steel Kpemou Apou Martial, Pluvinage Guy * and Capelle Julien LEM3 - ENIM – Université de Lorraine on X65 steel - I i it i

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2452-3216 © 2021 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 IWPDF 2021 Chair, Tuncay Yalçinkaya i i rti l r t - - li ( tt :// r ti . r /li / - - / . ) r-r i r r i ilit f I ir, l i

2452-3216 © 2021 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 IWPDF 2021 Chair, Tuncay Yal ç inkaya 10.1016/j.prostr.2021.12.072