Numerical simulation and experimental verification of axial-directional crystallization purification process for high-purity gallium  

高纯镓轴向结晶提纯过程的数值模拟与实验

作　　者：You-dong DING Lan JIANG Zi-shen LI Gao-feng FU Liang YU 丁友东;姜澜;李子申;付高峰;喻亮(东北大学多金属共生矿生态化冶金教育部重点实验室,沈阳110819;东北大学冶金学院,沈阳110819;桂林理工大学有色金属及材料加工新技术教育部重点实验室,桂林541004)

机构地区：[1]Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education,Northeastern University,Shenyang 110819,China [2]School of Metallurgy,Northeastern University,Shenyang 110819,China [3]Key Laboratory of New Processing Technology for Nonferrous Metals&Materials of Ministry of Education,Guilin University of Technology,Guilin 541004,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第12期3404-3416,共13页中国有色金属学报（英文版）

基　　金：Project(51465014)supported by the National Natural Science Foundation of China;Project(Guike AA17204021-7)supported by the Innovation Driven Development Special Foundation of Guangxi,China。

摘　　要：A transient numerical model was applied to simulating the axial-directional crystallization purification(ADCP) process of gallium(Ga) raw material at different coolant temperatures(Tc), and the evolutions of melt/crystal(m/c) interface shape, temperature distribution and thermal stresses were simulated and analyzed. The results showed that the m/c interface shape, temperature distribution, and thermal stress in the Ga material were determined by the Tc in the crystallizer during the ADCP process. The temperature gradient and thermal stress in the grown Ga crystal increased with decreasing Tc. At Tc=15 ℃, the m/c interface shape was flat, and the temperature gradient was ideal. Therefore, the Ga materials with lower thermal stresses and suitable m/c interface shape, and an ideal efficiency of impurity removal were obtained. The purity of Ga reached 6 N standard by using ADCP process repeated 6 times at Tc of 15 ℃. The results of the simulation showed good agreement with the experimental results.采用瞬态数值模型模拟镓原料在不同冷端温度(Tc)下的轴向结晶提纯(ADCP)过程,分析熔晶界面形状、温度分布和热应力的变化。结果表明:在ADCP过程中,Tc决定镓材料内部的熔晶界面形状、温度分布和热应力。生长的镓晶体中温度梯度和热应力随着Tc的降低而增大。在Tc=15℃时,熔晶界面呈现平面或略凸的形状,可为镓材料提供理想的温度梯度、较低热应力、合适的熔晶界面和理想的杂质去除效率。采用ADCP工艺在Tc=15℃条件下重复6次,镓纯度可达到6N标准。计算数据与实验数据吻合较好。

关 键 词：high purity Ga axial-directional crystallization purification finite element method 

分 类 号：TF843.1[冶金工程—有色金属冶金]