Study of Nanometer-Sized Precipitation and Properties of Fire Resistant Hot-Rolled Steel

Metals

Kun Chen¹  Chengjia Shang¹  Xuemin Wang¹  Zhenjia Xie¹  Minghong Jiang¹  Zhendong Song²  Ya Tao² 

[1] Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, China;Technical Center of Inner Mongolia Baotou Steel Union Co., Ltd., Baotou 014010, China;

关键词: interphase precipitation;    high temperature strength;    stability;    low carbon;    low alloy steel;   

DOI  :  10.3390/met9111230

来源: DOAJ

【 摘 要 】

Nanometer-sized precipitated carbides in a low carbon Ti-V-Mo bearing steel were obtained through hot rolling and air cooling and were investigated by transmission electron microscopy (TEM). The nanometer-sized interphase-precipitated carbides have been found to exhibit an average diameter of ~6.1 ± 2.7 nm, with an average spacing of ~24−34 nm. Yield strength of 578 ± 20 MPa and tensile strength of 813 ± 25 MPa were achieved with high elongation of 25.0 ± 0.5% at room temperature. The nanometer-sized precipitation exhibited high stability after annealing at high temperatures of 600 °C and 650 °C for 3 h. Average diameters of carbides were statistically measured to be ~6.9 ± 2.3 nm and 8.4 ± 2.6 nm after tempering at high temperatures of 600 °C and 650 °C, respectively. The micro-hardness was ~263−268 HV0.1 after high temperature tempering, which was similar to the hot-rolled sample (273 HV0.1), and yield strength of 325 ± 13 MPa and 278 ± 4 MPa was achieved at elevated temperatures of 600 °C and 650 °C, respectively. The significant decrease of yield strength at 650 °C was attributed to the large decrease in shear modulus.

【 授权许可】

Unknown