摘要
为阐释MgO含量对CaO-SiO_2-Fe_2O_3-MgO-Al_2O_3体系富镁复合铁酸钙(以下简称SFCAM)生成的影响机制,利用XRD、SEM、EDS等方法分析了950~1 250℃条件下获得的CaO-SiO_2-Fe_2O_3-MgO-Al_2O_3体系(MgO含量为1.3%~3.9%)的物相组成、微观形貌等。结果表明:SFCAM开始生成温度区间为1 000~1 050℃,大量生成温度区间为1 150~1 200℃;当温度高于1 200℃时,SFCAM开始分解。确定当温度大于1 100℃,低MgO含量时,MgO主要以MgFe_2O_4、Ca_2Mg(Si_2O_7)(以下简称CMS)形式与铁铝酸钙(以下简称CFA)等反应生成SFCAM;高MgO含量时,MgO主要以CMS形式与CFA等反应生成SFCAM。
In order to elucidate the mechanism of effect of MgO content on the formation of magnesium rich composite calcium ferrite(hereinafter referred as SFCAM) in CaO-SiO_2-Fe_2O_3-MgO-Al_2O_3 system, the phase composition and micromorphology of the CaO-SiO_2-Fe_2O_3-MgO-Al_2O_3 system(with MgO content of 1.3%~3.9%) at temperature of 950~1 250 ℃ are studied by the methods of XRD, SEM and EDS. The results show that, the initial formation temperature range of Mg-rich SFCA is 1 000~1 050 ℃, and the temperature range of large amount of Mg-rich SFCA formation is 1 150~1 200 ℃; and when the temperature is higher than 1 200 ℃, the SFCAM begins to decompose. It is determined that when the temperature is higher than 1 100 ℃ and the content of MgO is low, MgO reacts with calcium ferric aluminate(hereinafter referred as CFA) and forms Mg-rich SFCA mainly in the form of MgFe_2O_4 and Ca_2Mg(Si_2O_7)(hereinafter referred as CMS). When the content of MgO is high, MgO reacts with CFA and forms SFCA mainly in the form of CMS.
引文
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