Strelenko N. Improvement of the high-temperature slag crust separation at submerged arc cladding on the basis of metallurgical and thermophysical methods.

In the paper there was shown that one of the determinating factors of high-temperature slag crust separation of multilayer cladding with overlapping the previous layer is the formation of spinels on interface between slag and metal. The mechanism of formation of complex compounds - spinels was given. It is defined that the spinel structure is determined by temperature conditions of slag melt crystallization. There was created the thermodynamic model to calculate the probability of formating of oxides, which determine spinel structure for the capability to provide high-temperature slag crust separation. The results of experimental researches have confirmed the efficiency of the developed thermo-dynamic method for calculation of spinel compound by quantitative criterion for proportions of compounds, which arc able to enter in to the composition of spinel structure. There was established the new capability to regulate the high-temperature sepa-ration by including the optimal concentration of zirconium dioxide into the into the slag coating, which at the insignificant concentrations in slag is able to minimize the spinel formation. Two technics of insertion of zirconium dioxide in to reaction zone of welding arc suggested: through the compound of powdered wire or fluxes. Experimental data allowed to explain the optimal zirconium dioxide concentration range in fluxes of slag system SiO2-TiO2-Al2O3-MnO-MgO-CaO-CaF2 to provide the high-temperature slag crust separation and to forecast the effect of separate elements. By the data of the research re-sults the flux for cladding of the component parts of complex configuration АНК-73