摘要
实验通过定组成的H_2/CO_2混合气控制氧分压,在温度为1 873 K、1 673 K、1 473 K,氧分压为1.22×10^(-8)~2.18×10^(-12)Pa、4.92×10^(-8)~8.79×10^(-12)Pa的范围内,研究了TiO_x-SiO_2-MgO系的析出相.结合XRD和EDS分析并对比汪大亚等人的研究可知,当氧分压较高(PCO∶PCO_2=5∶1)时,对于初始成分TiO_2∶MgO∶SiO_2摩尔比为60∶25∶15的试样,在1 873 K和1 673 K时的析出相为TiO_2,在1 473 K时其析出相为MgTi_2O_5;对于初始成分TiO_2∶Mg O∶SiO_2摩尔比为60∶15∶25的试样,在1 873 K时其析出相为TiO_2,在1 673 K和1 473 K时析出相为MgTi_2O_5.而当氧分压较低(PH_2∶PCO_2=600∶1、300∶1、150∶1)时,2种不同成分的试样在不同温度下的析出相均为黑钛石,并且随着氧分压的降低,黑钛石中的Mg含量逐渐减少.
The formed crystal phases in TiOx-SiO2-MgO system under various oxygen partial pressure at different temperature ranging from 1873 K to 1 473 K were characterized. The oxygen partial pressure was controlled by H2/CO2. In the H2/CO2 atmosphere（volume ratios of H2 to CO2are 300 and 150）, the corresponding oxygen partial pressure at 1 873 K, 1 673 K and 1 473 K ranged from 1.22 ×10^-8-2.18×10^-12 Pa and 4.92×10^-8-8.79 ×10^-12 Pa respectively. The crystal phase was identified by combining X-ray diffraction with energy dispersive spectrometer analysis（EDS）. Comparing with the previous study, the results demonstrate that when the oxygen partial pressure is relatively high（volume ratio of CO to CO2 is 5）, for the sample with the molar ratio of TiO2： MgO ： SiO2 equal to 60 ： 25 ： 15, TiO2 crystal phase formed at 1 873 K and 1 673 K, Mg Ti2O5 formed at1 473 K. for the sample with the molar ratio of TiO2： MgO ： SiO2 equal to 60 ： 15 ： 25, TiO2 crystal phase formed at 1 873 K, Mg Ti2O5 formed at 1 673 K and 1 473 K. When the oxygen partial pressure is relatively low（volume ratio of H2 to CO2 is 600, 300 and 150）, the precipitated crystal phase of all the samples at three different temperature are anosovite, and the content of magnesium in anosovite decreased with the reduction of oxygen partial pressure.
出处
《有色金属科学与工程》
CAS
2016年第5期1-6,共6页
Nonferrous Metals Science and Engineering
基金
钢铁冶金新技术国家重点实验室自主研发课题(41603010)
关键词
氧分压
熔渣
黑钛石
相平衡
oxygen partial pressure
slag
anosovite
crystal phase precipitation
