Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel
Controlling continuous cooling is considered an effective means of producing high-strength and high-toughness bainitic steel. A medium carbon bainite frog steel is designed. By combining a thermal dilatometer with in-situ high-temperature metallography, the influence of continuous cooling rate on th...
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| Format: | Article |
| Language: | English |
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Elsevier
2024-03-01
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| Series: | Journal of Materials Research and Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S223878542400098X |
| _version_ | 1797247849480585216 |
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| author | Xiaoyan Long Wei Liu Ranran Zhu Yu Zhang Fucheng Zhang Zhinan Yang Yanguo Li |
| author_facet | Xiaoyan Long Wei Liu Ranran Zhu Yu Zhang Fucheng Zhang Zhinan Yang Yanguo Li |
| author_sort | Xiaoyan Long |
| collection | DOAJ |
| description | Controlling continuous cooling is considered an effective means of producing high-strength and high-toughness bainitic steel. A medium carbon bainite frog steel is designed. By combining a thermal dilatometer with in-situ high-temperature metallography, the influence of continuous cooling rate on the phase transformation of bainitic steel in the medium temperature range (500-365 °C) is studied. The microstructure and crystallographic orientation are characterized. The results indicate that with the increase of cooling rate in the temperature range for bainitic transformation, the initial temperature of bainitic transformation significantly decreases, and the transformation kinetics enhance, which causes the cooling rate for obtaining a maximum fraction of bainite significantly shifts to the left. As the cooling rate increases, the morphology of the bainite changes from a mixture of granular and coarse lath-like forms to fine lath-like forms. The volume fraction and average size of retained austenite as well as the size of bainite laths decrease with the increase of cooling rate. In addition, there are significant differences in the high-angle interface under different cooling rates, which is related to the variant selection mechanism of bainitic transformation at different cooling rates. The research results reveal the transformation process and microstructure evolution of bainite under different cooling rates in the medium temperature range, providing support for the microstructure control and performance optimization of bainite frog steel under continuous cooling control. |
| first_indexed | 2024-03-08T13:01:52Z |
| format | Article |
| id | doaj.art-030a8bd7f4dc4ac481cb4a84dc6b3842 |
| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-04-24T20:05:14Z |
| publishDate | 2024-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj.art-030a8bd7f4dc4ac481cb4a84dc6b38422024-03-24T06:57:15ZengElsevierJournal of Materials Research and Technology2238-78542024-03-01295066Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steelXiaoyan Long0Wei Liu1Ranran Zhu2Yu Zhang3Fucheng Zhang4Zhinan Yang5Yanguo Li6Guangdong Key Laboratory of Materials and Equipment in Harsh Marine Environment, Guangzhou Maritime University, Guangzhou, Guangdong, 510725, China; State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, China; Corresponding author. Guangdong Key Laboratory of Materials and Equipment in Harsh Marine Environment, Guangzhou Maritime University, Guangzhou, Guangdong, 510725, China.State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, ChinaState Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, ChinaState Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, ChinaCollege of Metallurgy and Energy, North China University of Science and Technology, Tangshan, Hebei, 063210, China; Corresponding author.State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, ChinaState Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, ChinaControlling continuous cooling is considered an effective means of producing high-strength and high-toughness bainitic steel. A medium carbon bainite frog steel is designed. By combining a thermal dilatometer with in-situ high-temperature metallography, the influence of continuous cooling rate on the phase transformation of bainitic steel in the medium temperature range (500-365 °C) is studied. The microstructure and crystallographic orientation are characterized. The results indicate that with the increase of cooling rate in the temperature range for bainitic transformation, the initial temperature of bainitic transformation significantly decreases, and the transformation kinetics enhance, which causes the cooling rate for obtaining a maximum fraction of bainite significantly shifts to the left. As the cooling rate increases, the morphology of the bainite changes from a mixture of granular and coarse lath-like forms to fine lath-like forms. The volume fraction and average size of retained austenite as well as the size of bainite laths decrease with the increase of cooling rate. In addition, there are significant differences in the high-angle interface under different cooling rates, which is related to the variant selection mechanism of bainitic transformation at different cooling rates. The research results reveal the transformation process and microstructure evolution of bainite under different cooling rates in the medium temperature range, providing support for the microstructure control and performance optimization of bainite frog steel under continuous cooling control.http://www.sciencedirect.com/science/article/pii/S223878542400098XBainitic transformationCooling rateLSCMVariant selection |
| spellingShingle | Xiaoyan Long Wei Liu Ranran Zhu Yu Zhang Fucheng Zhang Zhinan Yang Yanguo Li Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel Journal of Materials Research and Technology Bainitic transformation Cooling rate LSCM Variant selection |
| title | Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel |
| title_full | Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel |
| title_fullStr | Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel |
| title_full_unstemmed | Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel |
| title_short | Effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide-free bainitic steel |
| title_sort | effect of the cooling rate in the medium temperature zone on the phase transformation and microstructure of carbide free bainitic steel |
| topic | Bainitic transformation Cooling rate LSCM Variant selection |
| url | http://www.sciencedirect.com/science/article/pii/S223878542400098X |
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