Electrometallurgy Today, 2022, №04



2022 №04 (08)

DOI of Article 10.37434/sem2022.04.01

2022 №04 (02)

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Electrometallurgy Today (Sovremennaya Elektrometallurgiya), 2022, #4, 3-8 pages

Niobium refining by the method of cold-hearth electron beam melting

S.V. Akhonin, V.O. Beresos, O.M. Pikulin, O.O. Kotenko, Yu.T. Ishchuk

E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

Abstract
The technology of cold-hearth electron beam melting was used to perform a package of research work to produce quality ingots of high-purity metallic niobium with improved technical and economic parameters of the process. Proceeding from the results of the performed work, it was established that of all the interstitial impurities nitrogen is removed the worst from niobium during cold-hearth electron beam melting. This is the impurity which limits the refining process. Experimental data, obtained during operation, showed that the proposed modes of cold-hearth double electron beam remelting of niobium ensure rather uniform distribution of impurity elements in the ingot volume, whereas their content does not exceed the values specified by the standard requirements. It is found that application of the technology of electron beam melting of the ingot surface ensures removal of defects from the surface layer of niobium ingots, surface roughness being in the range of Rz20…Rz80 at surface relief waviness equal to 0.2…0.6 mm, respectively. Ref. 20, Tabl. 1, Fig. 6.
Keywords: niobium; electron beam melting; cold hearth; ingot; chemical composition

Received 26.09.2022

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