Effects of Nb and V on Microstructural Evolution,Precipitation Behavior and Tensile Properties in Hot-rolled Mo-bearing Steel

• Published in: Journal of iron and steel research, international Vol. 23; no. 6; pp. 559 - 565
• Main Authors: LIU, Fu-ming, WANG, Jian-jun, LIU, Yu-jie, MISRA, R.D.K., LIU, Chun-ming
• Format: Journal Article
• Language: English
• Published: Singapore Elsevier Ltd 01.06.2016; Springer Singapore
• Subjects: Applied and Technical Physics; Engineering; high temperature strength; Machines; Manufacturing; Material; Materials Engineering; Materials Science; Metallic Materials; microstructural evolution; Mo-bearing steel; Physical Chemistry; precipitate; Processes; 影响实验; 拉伸性能; 析出行为; 热轧钢; 组织性能; 组织演变; 轴承钢; 钼; precipitate; Mo-bearing steel; microstructural evolution; high temperature strength
• ISSN: 1006-706X; 2210-3988
• DOI: 10.1016/S1006-706X(16)30088-7

Microstructural evolution, precipitation behavior, and tensile properties of four experimental Mo-bearing steels were studied to elucidate the effects of Nb and V on microstructural properties. The results indicated that the microstructure of hot-rolled steels consisted of polygonal ferrite and degenerate pearlite, and the morphology remained same after holding at 600 °C for 1 h. The smallest grain size was obtained in Nb-V-Mo containing steel, followed by Nb-Mo and V-Mo steels. Precipitation was less in the hot-rolled Mo-bearing steel. The maximum volume fraction of precipitates was obtained in Nb-V-Mo bearing steel, and the Nb-V-Mo complex carbonitrides were highly stable at 600 °C. In the Mo-bearing steel, the yield ratio was lowest at room temperature but highest at 600 °C, which was attributed to the precipitation of Mo carbides and drag effect of Mo solute on dislocation movement.