Study of double electron beam refining at melting of hafnium metal sponge

Abstract

The possibility of the refining of hafnium metal sponge by e-beam double melting process is studied in this work. For this purpose, the effect of kinetic and thermodynamic parameters on the behavior of the impurities present in the base metal and their influence on the microstructure of the samples produced after double electron beam refining are investigated. The vapor (partial) pressure of hafnium, the controlled metallic inclusions (impurities) and their oxides as well as the relative volatility for the inclusions in the investigated hafnium material were evaluated. The process efficiency and the degree of refining with respect to the controlled impurities for each technological mode at double refining of hafnium sponge material were assessed based on thermodynamic analysis and conducted experiments.