电子束熔炼提纯钨中杂质脱除静态动力学研究

Static Kinetics of Removal of Impurities from Tungsten Melt during Electron Beam Melting

研究了电子束熔炼提纯钨过程中典型杂质的脱除,考察了电子束熔炼提纯钨的可行性,对电子束熔炼过程中的除杂动力学进行了分析,并确定了110、130、250 kW功率条件下杂质Fe、Si、Ti的脱除速率控制机制。结果表明:除Mo外,电子束熔炼对基体钨中各种杂质均有不同程度的脱除,其脱除率与饱和蒸气压差存在对应关系;通过分析并结合电子束熔炼实验,确定了Si、Fe、Ti在110 kW时的传质系数分别为0.21、0.56、0.11×10-4 m/s,在130 kW时的传质系数分别为0.83、3.04、1.78×10-4 m/s,在250 kW时的传质系数分别为0.36、2.37、1.48×10-4 m/s,表明其脱除速率控制机制均为液/气界面中的扩散。

The removal of typical impurity from tungsten using electron beam melting was studied. The feasibility of electron beam melting purification of tungsten was investigated. The impurity removal kinetics of electron beam melting was analyzed, and the removal rate control mechanism of Fe, Si and Ti at the power of 110, 130, and 250 kW was obtained. The results show that various impurities can be removed from the tungsten matrix by electron beam melting except Mo, and the removal efficiency and saturated vapor pressure difference are closely related. Kinetics analysis of removal of impurities and electron beam melting experiment indicate that Si, Fe and Ti is controlled by liquid-gas interface mass transfer with the mass transfer coefficient of 0.21, 0.56, 0.11×10^-4m/s at 110 kW, and 0.83, 3.04, 1.78×10^-4 m/s at 130 kW, whereas 0.36, 2.37, 1.48×10^-4 m/s at 250 kW, respectively.