Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment
In this study, a novel multi-step heat treatment method, including intercritical annealing and tempering, is proposed to improve the low-temperature toughness of Fe-6.5Mn-0.08C medium-manganese (Mn) steel. The effects of the subsequent tempering treatment on the microstructural evolution and low-tem...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-09-01
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| Series: | Journal of Materials Research and Technology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785423019671 |
| _version_ | 1797646740645478400 |
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| author | Seung-Hyeok Shin Young-Chul Yoon Sang-In Lee Byoungchul Hwang |
| author_facet | Seung-Hyeok Shin Young-Chul Yoon Sang-In Lee Byoungchul Hwang |
| author_sort | Seung-Hyeok Shin |
| collection | DOAJ |
| description | In this study, a novel multi-step heat treatment method, including intercritical annealing and tempering, is proposed to improve the low-temperature toughness of Fe-6.5Mn-0.08C medium-manganese (Mn) steel. The effects of the subsequent tempering treatment on the microstructural evolution and low-temperature toughness of medium-Mn steel were investigated and compared with those of a single intercritical annealing treatment. Medium-Mn steel subjected to intercritical annealing exhibited a duplex microstructure composed of martensite and nanolaminate-retained austenite. The subsequent tempering treatment after intercritical annealing generated a more homogenous distribution of retained austenite, together with an increase in the volume fraction of the retained austenite. The uniformly distributed retained austenite prevented Mn segregation at prior austenite grain boundaries, and the high fraction of retained austenite effectively inhibited crack propagation, leading to an improvement in the low-temperature toughness. In addition, the subsequent tempered medium-Mn steel contained a considerable amount of retained austenite, which could transform into martensite during the impact test, resulting in an impact fracture morphology that changed from cleavage facets to dimples at low temperatures. |
| first_indexed | 2024-03-11T15:06:03Z |
| format | Article |
| id | doaj.art-ba7df6ff9b9b4bd099055f224c4e300a |
| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-03-11T15:06:03Z |
| publishDate | 2023-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj.art-ba7df6ff9b9b4bd099055f224c4e300a2023-10-30T06:03:38ZengElsevierJournal of Materials Research and Technology2238-78542023-09-012635583570Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatmentSeung-Hyeok Shin0Young-Chul Yoon1Sang-In Lee2Byoungchul Hwang3Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul, 01811, Republic of KoreaDepartment of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul, 01811, Republic of KoreaDepartment of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul, 01811, Republic of KoreaCorresponding author. Department of Materials Science and Engineering, Seoul National University of Science and Technology (SEOULTECH), 232 Gongneung-ro, Nowon-gu, Seoul 01811, Republic of Korea.; Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul, 01811, Republic of KoreaIn this study, a novel multi-step heat treatment method, including intercritical annealing and tempering, is proposed to improve the low-temperature toughness of Fe-6.5Mn-0.08C medium-manganese (Mn) steel. The effects of the subsequent tempering treatment on the microstructural evolution and low-temperature toughness of medium-Mn steel were investigated and compared with those of a single intercritical annealing treatment. Medium-Mn steel subjected to intercritical annealing exhibited a duplex microstructure composed of martensite and nanolaminate-retained austenite. The subsequent tempering treatment after intercritical annealing generated a more homogenous distribution of retained austenite, together with an increase in the volume fraction of the retained austenite. The uniformly distributed retained austenite prevented Mn segregation at prior austenite grain boundaries, and the high fraction of retained austenite effectively inhibited crack propagation, leading to an improvement in the low-temperature toughness. In addition, the subsequent tempered medium-Mn steel contained a considerable amount of retained austenite, which could transform into martensite during the impact test, resulting in an impact fracture morphology that changed from cleavage facets to dimples at low temperatures.http://www.sciencedirect.com/science/article/pii/S2238785423019671Medium-Mn steelMicrostructureLow-temperature toughnessMulti-step heat treatmentRetained austenite |
| spellingShingle | Seung-Hyeok Shin Young-Chul Yoon Sang-In Lee Byoungchul Hwang Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment Journal of Materials Research and Technology Medium-Mn steel Microstructure Low-temperature toughness Multi-step heat treatment Retained austenite |
| title | Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment |
| title_full | Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment |
| title_fullStr | Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment |
| title_full_unstemmed | Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment |
| title_short | Improvement in low-temperature toughness of Fe-6.5Mn-0.08C Medium-Mn steel by multi-step heat treatment |
| title_sort | improvement in low temperature toughness of fe 6 5mn 0 08c medium mn steel by multi step heat treatment |
| topic | Medium-Mn steel Microstructure Low-temperature toughness Multi-step heat treatment Retained austenite |
| url | http://www.sciencedirect.com/science/article/pii/S2238785423019671 |
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