Autor: |
Nadezhda Polekhina, Valeria Linnik, Igor Litovchenko, Kseniya Almaeva, Sergey Akkuzin, Evgeny Moskvichev, Vyacheslav Chernov, Mariya Leontyeva-Smirnova, Nikolay Degtyarev, Kirill Moroz |
Jazyk: |
angličtina |
Rok vydání: |
2022 |
Předmět: |
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Zdroj: |
Metals, Vol 12, Iss 11, p 1928 (2022) |
Druh dokumentu: |
article |
ISSN: |
2075-4701 |
DOI: |
10.3390/met12111928 |
Popis: |
In this work, we study the effect of high-temperature thermomechanical treatment (HTMT) with deformation in the austenite region on the microstructure, tensile properties, impact toughness, and fracture features of advanced low-activation 12% chromium ferritic-martensitic reactor steel EK-181. HTMT more significantly modifies the steel structural-phase state than the traditional heat treatment (THT). As a result of HTMT, the hierarchically organized structure of steel is refined. The forming grains and subgrains are elongated in the rolling direction and flattened in the rolling plane (so-called pancake structure) and have a high density of dislocations pinned by stable nanosized particles of the MX type. This microstructure provides a simultaneous increase, relative to THT, in the yield strength and impact toughness of steel EK-181 and does not practically change its ductile-brittle transition temperature. The most important reasons for the increase in impact toughness are a decrease in the effective grain size of steel (martensite blocks and ferrite grains) and the appearance of a crack-arrester type delamination perpendicular to the main crack propagation direction. This causes branching of the main crack and an increase in the absorbed impact energy. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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