New carbon-fluorine additives for welding fluxes

Abstract

The influence of a carbon-fluorine additive in AN-348, AN-60, and AN-67 oxidative flux on the welding of 09Γ2C steel and in OK Flux 10.71 basic aluminate flux on the welding of 10XCHД steel is studied experimentally. The composition of the additive is as follows: 14.01–22.72% Al, 13–22.04% F, 13.16–21.34% C, 8.27–13.4% Na, 0.09–0.14% K, 0.66–1.09% Ca, 26.11–42.35% SiO₂, 1.15–1.86% FeO, 0.07–0.12% MnO, 0.001–0.1% MgO, 1.47–2.38% S, and 0.03–0.05% P. The experiments show that the use of carbon as the reducing agent is optimal in terms of preventing the formation of nonmetallic inclusions in the weld seam, since its gaseous compounds CO and CO₂ are easily captured and do not introduce nonmetallic inclusions in the weld seam. With 4–6% carbon-fluorine additive in the fluxes, the total oxygen content in the seam falls. When using the proposed additive, the mechanical properties and the impact strength at negative temperatures are improved on account of the lower content of nonmetallic inclusions (oxides) in the weld seam. The carbon concentration in the weld seam remains the same as in the basic steel.