Effect of microalloying elements on microstructure and properties of quenched and tempered constructional steel

2017 3rd International Conference on Applied Materials and Manufacturing Technology

Ma, Qingshen^1,2 ; Huang, Leqing^1,2 ; Di, Guobiao^1,2 ; Wang, Yanfeng^1,2 ; Yang, Yongda^1,2 ; Ma, Changwen^1,2

Shougang Research Institute of Technology, Beijing

100041, China^1

Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology, Beijing

100043, China^2

关键词: Bainite transformations;    Constructional steels;    Ferrite transformation;    Incubation time;    Micro-alloying elements;    Microstructure and properties;    Quenched and tempered steel;    Secondary carbides;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/242/1/012036/pdf
DOI  :  10.1088/1757-899X/242/1/012036

来源: IOP

【 摘 要 】

The effects of microalloying elements Nb, V and Ti on microstructure and properties of quenched and tempered steel were studied. Results showed that the addition of microalloying elements led to the formation of bainite and increased strength, while the austenization and ferrite transformation temperature was barely affected, i.e. 10°C. Microalloying elements shortened the incubation time for bainite transformation by refinement of austenite grain, and decreased the hardenability by forming carbides and therefore reducing the carbon content of super-cooled austenite. Either of them promoted the bainite transformation. The better tempering stability was ascribed to the as hot-rolled bainite microstructure and secondary carbide precipitation during tempering.