PSI - Issue 30

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2020) 000–000 il l li i i

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www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 30 (2020) 45–52

© 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 EURASTRENCOLD - 2020 guest editors The connection between occurrence of remarkable impact toughness scattering in ductile-to-brittle transition region and microstructure features of low carbon microalloyed steel was established by means of multiple impact toughness tests and electron backscatter diffraction microstructure measurements. The phenomenon of local inhomogeneity in ductility of plastic zone was established on the base of different microcracks nature revealed by electron backscatter diffraction. The residual microcracks occur in local embrittled regions of material as a result of cleavage at the early stage of fracture. Pre-strained regions with local ductility variations are fractured by the formation of splittings and by the ductile tearing. Pancaked parent austenite microstructure, various ferritic microstructures and martensite-austenite constituent along with the significant grain size variations can be considered as the sources for the occurrence of remarkable impact toughness scattering in low carbon microalloyed steels during fracture in ductile-to-brittle transition region. © 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 EURASTRENCOLD - 2020 guest editors Keywords: Impact toughness; Ductile-to-brittle transition; Microcracks; Microstructure; EBSD h Au r . u i ELS V Thi a c a ic und - cen ( / IX Eurasian Symposium on the problems of strength and resource in low climatic temperatures (EURASTRENCOLD-2020) The microstructure of low carbon microalloyed steel and impact toughness scattering during fracture in ductile-to-brittle transition region M. М . Kantor a , K.G. Vorkachev a *, V.A. Bozhenov a , K.A. Solntsev a a New technologies of metallic and ceramic materials laboratory, A.A. Baikov Institute of metallurgy and materials science of Russian academy of sciences, Leninsky awe. 49, Moscow, 119334, Russia , . . , . , , , Abstract

* E-mail address: kvorkachev@imet.ac.ru . .

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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 the responsibility of the EURASTRENCOLD - 2020 guest editors . .

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 EURASTRENCOLD - 2020 guest editors 10.1016/j.prostr.2020.12.009