The 'preflux' obtained from a vitreous matrix containing 30 percent liquid glass compared to the dry mass of the matrix, presents a basicity of B =1.08, a chemical activity of A_f = 0.43, and good technological characteristics during the SAW process. It enables a cord to be produced whose chemical composition, in the third deposition, with losses of 10 percent of the manganese and 25 percent of the C_(gf) referred to the wire-electrode, while the silica content is increased 13 fold. The selected proportions of FeCr, FeMn and C_(gf) in the alloyed load enabled a study to be made of the combined effect of the manganese and the C_(gf) in regulating the oxidation of the chromium transferred to the welding cord, expressed by the index of the oxidising screening effect I_(ap)(Cr)_(Mn,C), which in turn presents a multiplicative dependence with the transfer coefficient of chromium K_t(Cr), for the range of concentrations and elements studied: Cr = 21.8-48.4 percent, Mn = 4.2-33.8 percent, C_(gf) =4.8-14.3 percent. The agglomerate fluxes, prepared with 18.75 percent of alloyed load (FeCr, MeMn and C_(gf) in different proportions) and 81.5 percent matrix constituents (70.54 percent matrix and 10.71 percent sodium silicate), presented, for certain constant welding parameters (U_s =30 V, I_s =400 A, V =30 m/h), different alloy element transfer capacities: K_t(Cr)_(dep)=25.0-57.1 percent, K_t(Mn)_(dep) = 27.5-77.3 percent, K_t(C)_(dep)= 28.2-44.5 percent, which in turn depend on their capacity to oxidise in the presence of high concentrations of iron and in the energy conditions of the arc. The determination of the transfer coefficients, based on the laws of conservation of mass and on repartition, achieved by calculating the index of oxidising screening index I_(ap)(Cr)_(Mn,C), enabling mixtures of FeCr-FeMn-C_(gf) system alloyed loads of agglomerate fluxes with SiO_2-Al_2O_3-(CaO)+(MgO) system vitreous matrices, according to the chemical composition of the welding cord to obtain, and to define its production costs.
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