真空二次还原精炼法制备低氧高钛铁合金的研究

以铝热法生产的高钛铁为原料,以Al为还原剂进行真空还原精炼制备低氧高钛铁。研究了精炼温度、精炼时间等因素对精炼效果的影响,采用XRD、SEM及化学元素分析等手段对高钛铁合金进行了表征。结果表明:精炼后的高钛铁主要含有TiFe2、Fe2TiO5、TiO、Al2O3、TiAl、Fe0.942O等相,精炼后合金的微观结构均匀致密,夹杂物得到有效去除,氧含量大幅降低。但精炼温度过高,精炼时间过长,会恶化精炼效果。精炼后合金中钛含量(质量分数)为(69.00～71.00)%,铝含量低于2.50%,硅含量低于2.63%,氧含量低于3.52%,完全符合优质高钛铁的技术指标。

Research on Preparation of High Titanium Ferroalloy with Low Oxygen through Vacuum Secondary Reduction Refining

The vacuum reduction refining was used to prepare the high titanium ferroalloy with low oxygen, using the high titanium ferroalloy prepared by an aluminum thermal method as raw materials, and Al as the reducing agent. Effects of the refining temperature and time on the refining result were studied, and the high titanium ferroalloy was characterized by XRD, SEM and chemical elemental analysis. The results show that the refined high titanium ferroalloy consists mainly of TiFe2, Fe2TiO5, TiO, Al2O3, TiAl and Fe0.942O phases. The microstructure of the refined alloy is uniform and compact, the inclusions in the alloy are effectively removed and the oxygen content decreases dramatically. However, too high refining temperature and too long refining time will worsen refining effect. The titanium content in the refined alloy is within (69.00-71.00)%, Al content is lower than 2.50%, silicon content is lower than 2.63%, and the oxygen content is lower than 3.52%, which is fully consistent with the technical indicators of the high quality high titanium ferroalloy.