Precipitation Behavior and Microstructural Evolution of Ferritic Ti–V–Mo Complex Microalloyed Steel

• Published in: Acta metallurgica sinica : English letters 2018-09, Vol.31 (9), p.997-1005
• Main Authors: Zhang, Ke, Wang, Hui, Sun, Xin-Jun, Sui, Feng-Li, Li, Zhao-Dong, Pu, En-Xiang, Zhu, Zheng-Hai, Huang, Zhen-Yi, Pan, Hong-Bo, Yong, Qi-Long
• Format: Article
• Language: English
• Subjects: Carbon; Characterization and Evaluation of Materials; Chemistry and Materials Science; Coiling; Cooling; Corrosion and Coatings; Equilibrium; Evolution; Grain boundaries; Grain refinement; Hardness; Heavy construction; High strength low alloy steels; Hot rolling; Materials Science; Mechanical properties; Metallic Materials; Microalloying; Microscopy; Microstructure; Molybdenum; Nanotechnology; Nucleation; Organometallic Chemistry; Outdoor air quality; Precipitates; Precipitation hardening; Spectroscopy/Spectrometry; Steel; Temperature; Tensile strength; Titanium; Tribology; Vanadium
• ISSN: 1006-7191; 2194-1289
• DOI: 10.1007/s40195-018-0726-4

Precipitation behavior of (Ti, V, Mo)C and microstructural evolution of the ferritic Ti–V–Mo complex microalloyed steel were investigated through changing coiling temperature (CT). It is demonstrated that the strength of the Ti–V–Mo microalloyed steel can be ascribed to the combination of grain refinement hardening and precipitation hardening. The variation of hardness (from 318 to 415 HV, then to 327 HV) with CT (from 500 to 600–625 °C, then to 700 °C) was attributed to the changes of volume fraction and particle size of (Ti, V, Mo)C precipitates. The optimum CT was considered as 600–625 °C, at which the maximum hardness value (415 HV) can be obtained. It was found that the atomic ratios of Ti, V and Mo in (Ti, V, Mo)C carbides were changed as the CT increased. The precipitates with the size of