CO气氛下CaO对铁晶须生长影响的原位观察和机理研究

In situ observation and mechanism research of the influence of CaO on the growth of iron whiskers under CO atmosphere

摘要: 利用光学体视显微镜和高温热台对CO气体还原Fe₂O₃过程进行原位观察,并结合扫描电镜、能谱和红外光谱分析,研究掺入CaO对还原过程中铁晶须生成和生长机理的影响.实验结果表明:铁晶须是在实现FeO→Fe转变时形成和不断生长的;CaO对氧化铁的还原有抑制作用,当掺入CaO质量分数 ≥ 8%时,没有铁晶须生成和生长.因此,可以通过控制CaO掺入量的方式抑制铁晶须的生成和生长,进而减少矿粉颗粒团聚的发生.

Abstract: The influences of CaO on the formation and growth of iron whiskers and their mechanism in the reduction of iron oxide under CO atmosphere were studied.In situ observations on the development of iron whiskers were carried out using a stereo optical microscope and a hot stage under CO atmosphere.The reduced samples were analyzed by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS) and Fourier transform infrared spectroscopy(FTIR).It is indicated that the formation and growth of iron whiskers proceed in the stage of FeO being reduced to Fe and CaO has a negative effect on the reduction of iron oxide.When the mass fraction of CaO mixing into the sample is more than 8%,iron whiskers can not be observed.Therefore,controlling the amount of CaO mixing into the sample can inhibit the formation and growth of iron whiskers and reduce ore grain agglomeration.