|
|
|
| Microstructural evolution and mechanical properties of laser-welded joints of medium manganese steel |
| Yang Cao1,2, Chong Luo3, Lin Zhao2, Yun Peng2, Liang Song1,2, Cheng-yong Ma2, Zhi-ling Tian2, Min-lin Zhong1, Yan-jie Wang2 |
| 1 School of Material Science and Engineering, Tsinghua University, Beijing 100084, China
2 Central Iron and Steel Research Institute, Beijing 100081, China
3 Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China |
|
|
|
|
Abstract The cold-rolled 5% medium Mn steel was butt-welded using a fiber laser. The microstructure, distribution of micro-hardness, and tensile properties of the base metal (BM) and welded joint were investigated. The results showed that the fusion zone of the welded joint had the highest microhardness due to the formation of 100% martensite. A finely mixed microstructure of martensite, ferrite, and austenite was formed in the heat-affected zone, and there was no softened zone in this area. The tensile test results indicated that the ultimate tensile strength and yield strength were higher for the joint than for BM. The joint efficiency was approximately 100%. All samples of the welded joint failed at the location of BM during tensile deformation. The fracture surfaces of the BM and welded joint were mainly ductile fractures. The BM and welded joint exhibited strain rate independence of the tensile strength and yield strength at strain rates of 0.01–1 s-1, while the yield strength of the BM and welded joint increased rapidly when the strain rate reached 5 s-1 due to changes in the dislocation movement mechanisms. The uniform elongation of the BM and welded joint decreased with increasing strain rate.
|
|
Received: 13 November 2018
Published: 25 January 2020
|
|
|
|
| Cite this article: |
|
Yang Cao,Chong Luo,Lin Zhao, et al. Microstructural evolution and mechanical properties of laser-welded joints of medium manganese steel[J]. Journal of Iron and Steel Research International, 2020, 27(1): 75-87.
|
|
|
|
| [1] |
Wan‑lin Wang, Guo‑min Ying, Jie Zeng, Hai‑hui Zhang. Effect of electropulsing treatment on solidification behavior of spring steels in a continuous casting mold simulator[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(6): 656-664. |
| [2] |
Chun‑xu Wang, Yuan‑hang Gao, Yong Li, Shun Han, Shao‑zun Liu, Peng‑jie Zhang. Effects of solid-solution temperature on microstructure and mechanical properties of a novel 2000 MPa grade ultra-high-strength steel[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(6): 710-718. |
| [3] |
Xiao-ping Ma, Dian-zhong Li. Coalescence-dominated microstructure evolution during solidification of 20SiMn steel[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(5): 506-516. |
| [4] |
Ming Lei, Wei‑jun Hui, Jiao‑jiao Wang, Yong‑jian Zhang, Xiao‑li Zhao. Microstructure and mechanical properties of hot-rolled V-microalloyed Al-containing medium-Mn steel[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(5): 537-548. |
| [5] |
Xi‑kou He, Zhi‑qiang Yang, Zhen Wang, Shi‑bin Qiao, Zheng‑dong Liu. Effect of Mn content on microstructure, tensile and impact properties of SA508Gr.4N steel for reactor pressure vessel[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(4): 461-470. |
| [6] |
Sang-in Lee, Byoungchul Hwang. Correlation of microstructure with tensile behavior and properties of API X70 pipeline steels subjected to strain aging[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2020, 27(3): 319-324. |
|
|
|
|
2020, Vol. 27 
