Effect of Carbon and Fluorine Added to Silicomarganese Slag Fluxes

Abstract

A welding flux containing silicomanganese slag with a flux additive based on dust taken from gas cleaning facilities of aluminum industry has been studied. The following has been studied: the effect of a carbon-and-fluorine-containing additive exerted on the content of total oxygen and hydrogen in the welding seam’s metal, as well as on the impact strength in the positive and negative temperature range. To make the welding flux, silicomanganese slag produced by the West Siberian Electrometallurgical Plant has been used as a base. Also, a flux additive has been used to make carbon-and-fluorine containing dust taken from the electrostatic precipitators of RUSAL’s aluminum-producing enterprises. The samples have been welded using an ASAW-1250 welding tractor. The chemical composition of the welded samples under study has been determined according to GOST (State Standard) 10543–98 by means of an atomic emission technique using a DFS-71 spectrometer and by means of means of an X-ray fluorescence technique using an XRF-1800 spectrometer. Fractional gas analysis has been performed using a LECO TC-600 analyzer. The welded samples have been tested for impact strength in the positive and negative temperature range using a pendulum impact testing machine according to GOST (State Standard) 9454–78. Upon using a carbon-and-fluorine-containing flux additive in the welding flux based on silicomanganese slag, the amount of oxygen and hydrogen in the welding seam’s metal exhibits a decrease. At the same time, the impact strength in the positive and negative temperature range exhibits an increase. The curves for the amount of oxygen and hydrogen in the welding seam’s metal, as well as for the impact strength depending on the introduced amount of carbon-and-fluorine-containing flux additive, are plotted.