Electrometallurgy Today (Sovremennaya Elektrometallurgiya), 2018, #2, 37-40 pages
Nitrogen solubility in fluxes for electroslag technologies
G. M. Grigorenko, R. V. Kozin
E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
Abstract
Absorption of nitrogen from a gas phase by slags, which are used in electroslag technologies, was studied. The thermodynamics and kinetics of nitrogen absorption by calcium fluoride, which is a component of all the slags for electroslag technologies, were also studied. The relation between the content of nitrogen and carbon in calcium fluoride melt was established. Method of a weighted drop as applied to study the nitrogen solubility in all the fluxes was described. The equilibrium content of nitrogen was determined. Data are given about the nitrogen content in some fluxes after melting and after electroslag remelting. Data are given about carbon and nitrogen content in flux ANF-7, melted in arc flux melting furnace at different conditions of melting and blowing. The analysis of results of investigations showed that the nitrogen in fluxes of electroslag technologies is supposed to be in the form of CaCN
2 compounds. It is shown that fluxes, containing the large amount of calcium fluoride, are characterized by a low concentration of nitrogen and cannot be a source of metal enrichment with nitrogen during remelting, and possibly, can promote the gas removal from it. Ref. 11, Tabl. 3, Fig. 4.
Key words: nitrogen; carbon; solubility; metal; slag; flux melting furnace; electroslag technology; electroslag remelting
Received: 21.02.18
Published: 25.05.18
References
- Edneral, F.P. (1956) Change of nitrogen content in arc furnace arc furnace pool at different slag composition. Stal, 11, 10–12 [in Russian].
- Yavojsky, V.I. (1947) Gas transfer to metal through charge slag. Ibid., 9, 9–12 [in Russian].
- Ershov, G.S., Orlov, Yu.G. (1965) Nitrogen behavior in slag and metal phases in melting of alloyed steels. AN SSSR. Metally, 6 [in Russian].
- Ershov, G.S., Yakovlev, N.F., Malinovsky, E.I. (1968) Gases in fluxes and steel in electroslag remelting. In: Production and examination of steels and alloys. Moscow, Metallurgiya, 18–21 [in Russian].
- Kamyshev, V.M., Esin, O.A., Chuchmarev, S.K. (1964) Solubility of nitrogen in iron-free slags. Vuzov. Chyorn. Metallurgiya, 7, 24–28 [in Russian].
- Orlov, Yu.G., Filippov, S.I. (1967) Absorption and desorption of nitrogen by lime-aluminous slag. Ibid., 7, 11–15 [in Russian].
- Chuchmachev, S.K. et al. (1964) Kinetics of dissolution of nitrogen in molten iron-free slags. Ibid., 9, 21–23 [in Russian].
- Lev, I.E., Pokidishev, V.V., Lazarev, B.G., Mitskevich, N.S. (1987) Analysis of nitrogen-containing compounds in iron alloys. Moscow, Metallurgiya [in Russian].
- Novokhatsky, I.A. (1975) Gases in oxide melts. Moscow, Metallurgiya [in Russian].
- (1985) Atlas of slags: Refer. b Moscow, Metallurgiya [in Russian].
- Grigorenko, G.M., Pomarin, Yu.M. (1989) Hydrogen and nitrogen in metals in plasma melting. Kiev, Naukova Dumka [in Russian].