The influence of high heat input and inclusions control for rare earth on welding in low alloy high strength steel

2017 3rd International Conference on Applied Materials and Manufacturing Technology

Chu, Rensheng^1 ; Mu, Shukun^1 ; Liu, Jingang^1 ; Li, Zhanjun^1

Shougang Research Institute of Technology, Beijing

100043, China^1

关键词: Calcium aluminate;    Coarse grains;    Coarse-grained;    Grain size;    Holding time;    Low melting;    Ternary phase diagrams;    V-shaped notch;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/242/1/012065/pdf
DOI  :  10.1088/1757-899X/242/1/012065

来源: IOP

【 摘 要 】

In the current paper, it is analyzed for the influence of high heat input and inclusions control for rare earth on welding in low alloy high strength steel. It is observed for the structure for different heat input of the coarse-grained area. It is finest for the coarse grain with the high heat input of 200 kJ / cm and the coarse grain area with 400 kJ / cm is the largest. The performance with the heat input of 200 kJ / cm for -20 °C V-shaped notch oscillatory power is better than the heat input of 400 kJ / cm. The grain structure is the ferrite and bainite for different holding time. The grain structure for 5s holding time has a grain size of 82.9 μm with heat input of 200 kJ/cm and grain size of 97.9 μm for 10s holding time. For the inclusions for HSLA steel with adding rare earth, they are Al2O3-CaS inclusions in the Al2O3-CaS-CaO ternary phase diagram. At the same time, it can not be found for low melting calcium aluminate inclusions compared to the inclusions for the HSLA steel without rare earth. Most of the size for the inclusions is between 1 ∼ 10μm. The overall grain structure is smaller and the welding performance is more excellent for adding rare earth.