Welding wire of filling flux of gas protection electric arc welding using for high-strength steel

Abstract

Disclosed is a flux cored wire for gas shielded arc welding of high tensile strength steel, characterized in that the flux essentially consists of, with respect to the total weight of the wire: metal or ferroalloy containing at least Si, Mg and Al acting as a deoxidizing agent, the sum of the three components, Si, Mg and Al being from 0.5 to 1.5%; from 1.5 to 2.7% Mn, provided that the ratio of Mn to (Mg+Al), i.e., the value of Mn / (Mg+Al) is 3.5-5.0; and two or more components selected from the group consisting of Cr, Ni, Mo and Nb, the sum of the two or more components being 1.0-2.5%. The flux cored wire exhibits good welding workability in all welding positions, ensuring an improvement in the efficiency of welding work, and maintains high tensile strength and impact absorption energy, ensuring stability of welded structures.

Description

[0001] [Technical field of invention] [0002] This invention is about the 80kgf / mm 2 Invention of flux-filled wire for gas-shielded arc welding of high-strength steel, specifically 80kgf / mm 80kgf / mm for improving operability and low-temperature toughness by filling titanium dioxide-based flux 2 Invention of the flux-filled wire for gas-shielded arc welding of high-strength steel. [Background technique] [0003] Previously, almost all flux-filled wires used for high-strength steel sheets were 60 to 70 kgf / mm 2 In particular, it is difficult to maintain good elongation and low temperature toughness while maintaining high strength. Therefore, in order to satisfy high strength, elongation, and low-temperature toughness, welding rods coated with flux or welding wires filled with basic fluxes are mainly used. However, flux-coated welding rods and alkaline-based flux-filled welding wires have many problems, such as restrictions on where they can be used and poor operability. [...

AI Technical Summary

Problems solved by technology

However, flux-coated electrodes and alkaline-based flux-filled wires have many problems, such as restrictions on where they can be used and poor operability.

[0004] On the other hand, instead of filling the basic flux welding wire, the added TiO 2 Form slag together with other oxides, and sometimes cover the surface of the weld bead. As a result, a part of it exists in the weld metal in the form of non-metallic inclusions, or increases the oxygen content of the weld metal, which may reduce the toughness of the weld metal.