METALS AND METAL MATRIX COMPOSITES |
|
|
|
|
|
HAZ Microstructure Evolution of UNS S32750 Duplex Stainless Steel |
ZHANG Zhiqiang, CHU Haoran, ZHANG Tiangang, LU Xuecheng, ZHANG Yuhang, GUO Zhiyong*
|
School of Aeronautical Engineering, Civil Aviation University of China, Tianjin 300300, China |
|
|
Abstract Welding, as a common manufacturing method, is an indispensable part of the promotion and application of duplex stainless steel (DSS). However, the microstructure evolution behavior of the heat affected zone (HAZ) during multilayer and multipass welding of duplex stainless steel is still unclear. The influence of ferritization and reheating process on microstructure evolution at HAZ of UNS S32750 duplex stainless steel welding was studied by Gleeble3500 thermal simulator, thermodynamic methods and microstructure characterization techniques. The results show that the alternating bands of ferrite and austenite were transformed into coarse and equiaxed metastable ferrite as well as different types of primary austenite (γ1) after ferritization of HAZ, and the austenite content was significantly reduced. In addition, a large amount of Cr2N was precipitated within the ferrite grain, at the ferrite and ferrite grain boundary, as well as in the ferrite and austenite phase boundary. Furthermore, the subsequent reheating temperature after ferritization had a significant effect on the microstructure of the HAZ. With the increase of reheating temperature in the range from 900 ℃ to 1 200 ℃, the austenite gradually increased. At the same time, the higher reheating temperature can also decrease the precipitation tendency of Cr2N. In addition, secondary austenite (γ2) is easily precipitated at the reheating temperature of 1 000 ℃. Furthermore, γ2 and Cr2N exhibited an obvious assisted precipitation behavior.
|
Published: 10 November 2023
Online: 2023-11-10
|
|
Fund:National Natural Science Foundation of China (51905536), Science and Technology Program of Tianjin(21YDTPJC00430), Natural Science Foundation of Tianjin (22JCYBJC01280), and Fundamental Research Funds for the Central Universities of China (3122023039). |
|
|
1 Li H W, Zhao Z Y, Xue R D. Transactions of the China Welding Institution, 2022, 43(2), 20 (in Chinese). 栗宏伟, 赵志毅, 薛润东. 焊接学报, 2022, 43(2), 20. 2 Gao Z Q, Jing H Y, Xu L Y, et al. Transactions of the China Welding Institution, 2019, 40(7), 143 (in Chinese). 高站起, 荆洪阳, 徐连勇, 等. 焊接学报, 2019, 40(7), 143. 3 Dandekar T R, Gupta A, Khatirkar R K, et al. Transactions of the Indian Institute of Metals, 2021, 74, 2267. 4 Zhang Z Q, Jing H Y, Xu L Y, et al. Journal of Materials Heat Treatment, 2020, 41(5), 15 (in Chinese). 张志强, 荆洪阳, 徐连勇, 等. 材料热处理学报, 2020, 41(5), 15. 5 Yang Y Z, Wang Z Y, Tan H, et al. Corrosion Science, 2012, 65, 472. 6 Kim H J, Jeon S H, Kim S T, et al. Corrosion Science, 2014, 87, 60. 7 Chehuan T, Dreilich V, de Assis K S, et al. Corrosion Science, 2014, 86, 268. 8 Zhang Z Q, Jing H Y, Xu L Y, et al. Applied Surface Science, 2018, 435, 352. 9 Taban E, Kaluc E. Welding in the World, 2011, 55, 48. 10 Knyazeva M, Pohl M. Metallography, Microstructure, and Analysis, 2013, 5(2), 343. 11 Ferro P, Fabrizi A, Bonollo F, et al. Acta Metallurgica Slovaca, 2021, 27(2), 57. 12 Zhang Z Q, Jing H Y, Xu L Y, et al. Transactions of the China Welding Institution, 2017, 38(5), 79 (in Chinese). 张志强, 荆洪阳, 徐连勇, 等. 焊接学报, 2017, 38(5), 79. 13 Zhang Z Q, Jing H Y, Xu L Y, et al. Applied Surface Scienc, 2017, 404(15), 110. 14 Ramirez A J, Lippold J C, Brandi S D. Metallurgical and Materials Transactions A, 2003, 34(8), 1575. 15 Hosseini V A, Bermejo M, Gårdstam J, et al. Welding in the World, 2016, 60(2), 233. 16 Zhang Z Q, Jing H Y, Xu L Y, et al. Applied Surface Science, 2017, 26(1), 134. 17 Zhang Z Q, Jing H Y, Xu L Y, et al. Corrosion Science, 2017, 120, 194. |
|
|
|