Nb-7Ta合金电子束真空熔炼中元素挥发动力学研究

Study on Evaporation Kinetic Nb-7Ta Alloy in the EBM Vacuum Melting

摘要: 研究了电子束熔炼Nb-7Ta合金时基体铌和杂质铁挥发过程的动力学特性。结果表明:在3 473 K时,基体铌和杂质铁挥发过程均是以单原子形式进行。铌在铌钽合金液相中扩散系数为5.78×10^-7m/s,挥发反应的反应常数为1.29×10^-5m/s;铁在铌钽合金液相中扩散系数为8.10×10^-7m/s,挥发反应的反应常数为1.55×10^-5m/s。基体铌和杂质铁挥发过程均受各自原子在液相中扩散控制。

Abstract: The Evaporation kinetic characteristic of Nb-7Ta alloy in the EBM process were studied in this paper.The results show that the evaporation reaction of Nb and Fe was in the form of single atoms.The diffusion constant of Nb in the liquid Nb-7Ta alloy is 5.78 × 10^-7m / s; the reaction constant of Nb in the evaporation reaction is 1.29 × 10^-5m / s; the diffusion coefficient of Fe in liquid Nb-7Ta alloy is 8.10 × 10^-7m / s,the reaction coefficient of Fe in the evaporation reaction is 1.55 ×10^-5m / s.The evaporating process of matrix Nb as well as impurity Fe from the Nb-7Ta alloy liquid were both controlled by diffusion.