Sobol Y. Glasscoatings on the basis of Na2O - B2O3 - SiO2 system for the tin bronze protection during melting

Research object - the physical-chemical processes proceeding at glasscoating formation of glasscoating for tin bronze protection during melting. Research aim - working out of compositions, reception and application technologies of glasscoating on the basis of non scarce domestic raw materials which will reliably protect and refine tin bronze melt at fusion from secondary raw materials, be inert in relation to the melting furnace refractories and ecologically safe. Research methods - a complex of standard physical-chemical methods. Theoretical and practical results - are established laws of the tin bronze oxidation, consisting in monotonous growth of intensity of this process at 675-950 °С; the complex of requirements on properties of coatings for protection and refinement of tin bronze melt is formulated; with thermodynamic calculations and glasses researches in system Na2O-B2O3-SiO2 was established composition area for synthesis protectively-refining glasscoatings in triangle Na2O·2SiO2-Na2O·3SiO2-Na2O·2B2O3 that became the basis for the choice of industrial analogues: water glass (SG), cullet (SB) and borax (B), as components of such coatings; it were established the character of interaction with aluminosilicate and quartzcontaining refractories protectively-refining glasscoatings in SG-SB-B system depending on their compositions, and also the ratio of the components which have provided reduction corrosion liners of melting furnaces in 5 - 6 times in comparison with effective salt fluxes. Novelty - the principle of reception continuous gas-tight protective glasscoating by regulation of its viscosity within 106,1-103,64 Pa·s by consecutive crystallization sodiumsilicate and sodiumborosilicates compositions with their further fusion in a temperature interval of formation and service were offered. Introduction - is recommended to introduction into tin bronze production; branch of application - nonferrous metallurgy and mechanical engineering.