Chen M.,Northeastern University China |
Tian Z.,Northeastern University China |
Yu Q.,Northeastern University China |
Gao Z.,Hebei Iron and Steel Co.
Advanced Materials Research | Year: 2011
The metallurgical behavior of adjusted converter slag components during the selective reduction process were investigated by thermodynamic calculating with different modified slag composition, addition of reducing agent and reduction temperature. The activities of main slag components were drawn from the calculated values. The results showed that the activity of SiO2 increased with increment of its mass fraction in slag. The solubility of SiO2 increased with increment of temperature. The selective reduction was promoted by selecting the appropriate amount of modifier. Reduction order was elucidated in this paper, Fe was reduced from the slag followed by P, Mn and Si and the reduction rate of Si could reach about 51%. The metal phase was rich in Fe, Si, Mn and P as a result of the selective reduction. © (2011) Trans Tech Publications, Switzerland. Source
Lu C.-B.,Hebei Iron and Steel Co.
Kang T'ieh/Iron and Steel | Year: 2015
The metallurgical structure of the specimens with higher strength is detected by optical microscope, and there is more than 50% pseudo-eutectoid pearlite in the specimens, resulting in an effect of remarkable pearlite strengthening. Conclusion of comparative analysis of different process is that far more than balance content of pseudo-eutectoid pearlite can be gotten by inhibiting proeutectoid ferrite transformation and making final cooling temperature lower than the Ar1 of air cooling. The factors influencing the proeutectoid ferrite transformation during laminar cooling are discussed in this study. ©, 2015, Chinese Society for Metals. All right reserved. Source
Li F.-M.,Hebei United University |
Yi F.-Y.,Hebei Iron and Steel Co. |
Bai R.-G.,Hebei Iron and Steel Co. |
Sun K.,Hebei United University |
Lu Q.,Hebei United University
Kang T'ieh/Iron and Steel | Year: 2014
The binding phase strength of mixed iron ore with high limonite ratio was determined by micro-sintering apparatus at different sintering temperature, basicity and MgO content. The results reveal that, binding phase strength of mixed iron ore increased at first and then decreased as sintering temperature, basicity and MgO content increased. It reached the highest value when the sintering temperature was 1280 ℃, alkalinity was 1.6 and mass percent of MgO was 2.0%. Limonite ratio should be reduced appropriately in production, so that the mixed iron ore has adequate binding phase strength. ©, 2014, Chinese Society for Metals. All right reserved. Source
Tang X.-H.,University of Science and Technology Beijing |
Liu R.-Z.,University of Science and Technology Beijing |
Yao L.,University of Science and Technology Beijing |
Yao L.,Hebei Iron and Steel Co. |
And 4 more authors.
International Journal of Minerals, Metallurgy and Materials | Year: 2014
Ferronickel enrichment and extraction from nickel laterite ore were studied through reduction and magnetic separation. Reduction experiments were performed using hydrogen and carbon monoxide as reductants at different temperatures (700–1000°C). Magnetic separation of the reduced products was conducted using a SLon-100 cycle pulsating magnetic separator (1.2 T). Composition analysis indicates that the nickel laterite ore contains a total iron content of 22.50wt% and a total nickel content of 1.91wt%. Its mineral composition mainly consists of serpentine, hortonolite, and goethite. During the reduction process, the grade of nickel and iron in the products increases with increasing reduction temperature. Although a higher temperature is more favorable for reduction, the temperature exceeding 1000°C results in sintering of the products, preventing magnetic separation. After magnetic separation, the maximum total nickel and iron concentrations are 5.43wt% and 56.86wt%, and the corresponding recovery rates are 84.38% and 53.76%, respectively. © 2014, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. Source
Wu D.Y.,Yanshan University |
Pei J.P.,Yanshan University |
Gong Y.L.,Hebei Iron and Steel Co. |
Fan W.B.,Hebei Iron and Steel Co. |
And 2 more authors.
Materials Science and Technology (United Kingdom) | Year: 2014
The dynamic recrystallisation (DRX) and static recrystallisation (SRX) behaviours of three V-Ti microalloyed steels were studied by the analysis of the true stress-strain curves and the stress relaxation curves under different deformation conditions. The results of DRX showed that deformation activation energy Qdef, peak stress and peak strain increased, as a result of the solute strengthening and dragging effect due to Si. The results of SRX showed that Si increased the SRX activation energy QSRX. The solute retardation parameter for static recrystallisation of Si was calculated. Based on the SRX results, to quantify the drag effect of Si and V, a new model was proposed to describe the time for 50% recrystallisation (t0·5), which was tested and verified by previously published data on similar steels. Precipitation during recrystallisation could lead to a lower value of the Avrami exponent. © 2014 Institute of Materials, Minerals and Mining. Source