Exploitation of Mold Flux for the Ti-bearing Welding Wire Steel ER80-G

Abstract

Abstract In order to improve the surface defects of strand, the mold flux is exploited for the Ti-bearing welding wire steel ER80-G. The composition of mold flux is designed by analyzing the solidification characteristics of ER80-G and the slag system isothermal section diagram, simulating by the FactSage thermodynamics software. The Ti-bearing welding wire steel ER80-G belongs to the peritectic steel. The melting point range of the newly designed mold flux system is from 1030∘C to 1129∘C, the melting rate range is from 58 s to 64 s, the viscosity range at the temperature of 1300∘C is from 0.33 Pa·s to 0.50 Pa·s, the crystallization temperature range is from 1160∘C to 1293∘C, the crystalline fraction range is from 34% to 85%. The surface defects of strand which transverse depression, longitudinal depression, slag runner and so on were obviously improved when the newly design mold flux F3, F5, F9 were used to the production respectively. Those results suggest that 0.9 basicity with 28.4%-CaO, 31.6%-SiO2,3%-MgO, 10%-Na2O, 10%-CaF2, 6%-Al2O3, 1%-Fe2O3, 10%-T c and all groups with 1.0 and 1.1 basicity show the best properties for Ti-bearing welding wire steel ER80-G.