Effect of solid state SiO2 on the formation process of binary calcium ferrite
DING Xiang1,2， GUO Xing-min1,2
1. State Key Laboratory of Advanced Metallurgy， University of Science and Technology Beijing， Beijing 100083， China 2. School of Metallurgical and Ecological Engineering， University of Science and Technology Beijing， Beijing 100083， China
Abstract：The effect of SiO2 on the formation process of calcium ferrite which is the main composition of bonding phase in high basicity sinter is not very clear at present. So， X-ray diffraction(XRD)， ore microscope (OM)， and quantitative Rietveld analysis were used to analyze the effect of SiO2 on the formation process of binary calcium ferrite. Experimental results show that the initial reaction products of Fe2O3 with CaO is Ca2Fe2O5 at 700 ℃， then， Ca2Fe2O5 transforms to CaFe2O4 gradually with increasing temperature and CaFe2O4 appears when the temperature reached 800 ℃. Ca2SiO4 appears at the formation process of binary calcium ferrite when containing SiO2， and the amount of Ca2SiO4 is relatively less before 900 ℃ due to the influence of the dynamic conditions. In addition， a large amount of Ca2Fe2O5 appears due to it fails to transform to CaFe2O4 because of the hindrance of SiO2 with increasing content of SiO2. At last， Ca2Fe2O5 transforms to CaFe2O4 quickly because the formation reaction of CaFe2O4 is enhanced when the dynamic conditions improve with increasing temperature after 900 ℃ and Fe3+ through the CaFe2O4 layer is easier than Ca2+ through the Ca2Fe2O5 layer， however， the formation of CaFe2O4 is inhibited resulting from the production of Ca2SiO4 increased with increasing content of SiO2 and the contact area of CaO and Fe2O3 decreases.
丁 祥， 郭兴敏，. 固态下SiO2对二元铁酸钙形成过程的影响[J]. 钢铁, 2015, 50(3): 33-38.
DING Xiang，， GUO Xing-min，. Effect of solid state SiO2 on the formation process of binary calcium ferrite. Iron and Steel, 2015, 50(3): 33-38.
2015, Vol. 50 
