钛精粉氧化过程中物相转变

Phase transformation of titanium concentrate in the oxidation process

采用热重分析和恒温实验法研究了攀枝花钛精粉氧化过程中相的存在形式及其转变规律.X射线衍射结果和微观形貌分析表明:温度低于500℃,钛精粉未发生氧化反应;600℃时产生Fe2Ti3O9和TiO2相,其和原相Fe2O3相衍射峰强度均随温度的升高而增强;900℃时,Fe2Ti3O9相完全转变为Fe2TiO5相,且随温度的升高,TiO2相和Fe2O3相衍射峰强度逐渐减弱;在整个氧化过程中存在四个化学反应,其与烧结作用相互关联,使得氧化产物表面形成较多孔隙,变得凹凸不平且疏松.

The existence form and transformation pattern of phases in Panzhihua titanium concentrate during the oxidation process were studied by thermogravimetry,constant temperature tests,X-ray diffraction analysis and microstructure observations.The results show that the titanium concentrate is not oxidized by oxygen below 500 ℃.Fe2Ti3O9 and TiO2 phases start to form when the temperature is 600 ℃ and the diffraction peak intensities of Fe2Ti3O9,TiO2 and original phase Fe2O3 strengthen with the experimental temperature rising.When the temperature rises at 900 ℃,Fe2Ti3O9 is substituted by Fe2TiO5 and the diffraction peak intensities of TiO2 and Fe2O3 gradually weaken with the experimental temperature rising.Four chemical reactions concomitant with sintering effect occur in the oxidation process;they accelerate the formation of porosities and make the surface of oxidation products rough and loose.