2019 №06 (03)

DOI of Article 10.15407/as2019.06.04

2019 №06 (05)

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Avtomaticheskaya Svarka (Automatic Welding), #6, 2019, pp.29-32

Influence of refractory dispersed phases on physico-chemical properties of slag melts of the system MgO-Al₂O₃-SiO₂-CaF₂

I.O. Goncharov¹, V.S. Sudavtsova¹, D.D. Mishchenko¹, A.M. Duchenko¹, V.E. Sokolsky²

¹E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
²Taras Shevchenko National University of Kyiv. 60 Volodymyrska Str., 01601, Kyiv, Ukraine

The article is devoted to the study of basic mechanisms of control of structure and physical and chemical properties of slag oxide-fluoride melts in order to create fluxes with predicted chemical, metallurgical and technological parameters for welding high-strength low-alloyed steels. The addition of MgO in the slag melts of the system MgO-Al₂O₃-SiO₂-CaF₂ provides an abnormal decrease in the thermodynamic activity of silicon oxide in them due to the formation of a refractory dispersed phase MgO·Al₂O₃ in the melt. Based on the methods of internal standard and the proposed gravimetric procedure for determination of quantitative content of MgO·Al₂O₃  in liquid and solid slags of the system MgO-Al₂O₃-SiO₂-CaF₂ its optimum content in a slag melt was determined, in which the combination of optimal chemical, metallurgical and technological properties of flux during electric arc welding is provided. 12 Ref., 1 Tabl., 5 Fig.
Keywords: fluxes for electric arc welding, slag melts, refractory dispersed particles, toughness, electric conductivity, thermodynamic activity

Received: 15.04.2019
Published: 20.05.2019

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