The Paton Welding Journal, 2014, №04



2014 №04 (03)

DOI of Article 10.15407/tpwj2014.04.04

2014 №04 (05)

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The Paton Welding Journal, 2014, #4, 26-29

PREDICTION OF THERMODYNAMICAL PROPERTIES OF MELTS OF THE CaO-Al₂O₃ SYSTEM

I.A. GONCHAROV¹, V.I. GALINICH¹, D.D. MISHCHENKO¹ and V.S. SUDAVTSOVA²

¹E.O. Paton Electric Welding Institute, NASU. 11 Bozhenko Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
²I.M. Frantsevich Institute of Problems of Materials Science, NASU. 3 Krzhizhanovsky Str., 03680, Kiev, Ukraine. E-mail: goncharov@.paton.kiev.ua
 
 
Abstract
The expert evaluation of literature data was carried out and methods of calculation of thermodynamic properties of melts of the CaO-CaO-Al₂O₃ system in the whole concentration range were offered. Thermodynamic activities of aluminium oxide at 0.74 <  < 1 were calculated from the coordinates of the liquidus line of constitution diagram of the system CaO-CaO-Al₂O₃, determined by different authors. Using calculation and experimental data on thermodynamic activity of CaO-Al₂O₃, the evaluation of thermodynamic activities of calcium oxide was carried out by integration of Gibbs-Duhem equation. It was established that they reveal great negative deviations from thermodynamic properties of perfect solutions. Basing on the established values of thermodynamic activity of calcium oxide, the liquidus line of constitution diagram of the system CaO-CaO-Al₂O₃ was plotted on the side of calcium oxide. The obtained values of activity of components and liquidus temperature of the system CaO-CaO-Al₂O₃ allow evaluating the thermodynamic properties of corresponding three- and four-component systems, predicting processes of interaction in the metal-slag-gaz system and creating new consumables for welding and electroslag remelting. 28 Ref., 2 Tables, 4 Figures.
 
 
Keywords: welding, electroslag remelting, slag melts, thermodynamic activity of components, constitution diagram
 
 
Received:                17.01.14
Published:               28.04.14
 
 
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