Research on Microstructure and Properties of Welded Joint of High Strength Steel

2017 3rd International Conference on Environmental Science and Material Application

生态环境科学;材料科学

Zhu, Pengxiao^1,2 ; Li, Yi^1,2 ; Chen, Bo^1,2 ; Ma, Xuejiao^1,2 ; Zhang, Dongya^1,2 ; Tang, Cai^1,2

State Key Laboratory of Intelligent Manufacturing of Advanced Construction Machinery, Xuzhou Construction Machinery Group, Xuzhou

221004, China^1

Jiangsu Xuzhou Construction Machinery Research Institute, Xuzhou Construction Machinery Group, Xuzhou

221004, China^2

关键词: Coarse grain zone;    Fatigue Limit;    Granular bainites;    Impact energy;    Impact testers;    Lath martensite;    Microstructure and properties;    Tensile testing machines;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/108/2/022027/pdf
DOI  :  10.1088/1755-1315/108/2/022027

来源: IOP

【 摘 要 】

BS960 steel plates were welded by Laser-MAG and MAG. The microstructure and properties of the welded joints were investigated by optical microscope, micro-hardness tester, universal tensile testing machine, impact tester, scanning electron microscope (SEM) and fatigue tester. By a series of experiments, the following results were obtained: The grain size of the coarse grain zone with Laser-MAG welded joint is 20μm, and that with MAG welded joint is about 32μm, both of the fine grain region are composed of fine lath martensite and granular bainite; the width of the heat affected region with Laser-MAG is lower than that with MAG. The strength and impact energy of welded joints with Laser-MAG is higher than that with MAG. The conditioned fatigue limit of welded joint with Laser-MAG is 280MPa; however, the conditioned fatigue limit of welded joint with MAG is 250MPa.