Low-hydrogen easy-to-weld alkaline flux-cored wire prepared from steel slag and used for structural steel

Abstract

The invention belongs to the technical field of welding materials, and particularly relates to a low-hydrogen easy-to-weld alkaline flux-cored wire prepared from steel slag and used for structural steel. The flux-cored wire is formed in a manner that a low-carbon cold-rolled steel strip is wrapped with flux core powder, and the flux core powder comprises 22%-28% of steel slag, 7.5%-9.0% of Mo40V40Al20 powder, 5.6%-8.2% of FeMn60Si34C 0.02 powder, 4.1%-5.0% of FeTi80-A powder, 7.8%-9.6% of CaF2 powder plated with Ni on the surface, 4.2%-6.0% of nano TiO2, 3.1%-3.8% of 200-mesh nitrocellulose powder, 2.1%-3.0% of feldspar and the balance FHT100.25 iron powder reduced. During welding, the flux-cored wire is stable in electric arc, small in splashing, good in post-welding forming, easy to deslag, suitable for all-position welding, low in residual hydrogen content in deposited metal, uniform in chemical component and high in mechanical property, and is an innovation in the aspect of alkaline flux-cored wires.

Description

technical field [0001] The invention belongs to the technical field of welding materials, and in particular relates to a low-hydrogen easy-welding basic flux-cored welding wire for structural steel prepared by using steel slag. Background technique [0002] Basic welding materials have the advantages of low hydrogen, high toughness, high crack resistance and excellent mechanical properties. Basic welding wire is generally the first choice for welding important structural parts. The core powder of the existing basic flux-cored welding wire for structural steel welding is composed of mineral powder and alloy powder. Due to the problems in the components, the mineral powder should be added with alkaline substances such as marble and magnesium oxide. When welding structural steel, the main problems are: ①The molten droplet transitions in coarse particles, and the splash is large during the welding process; ②The fluidity of the slag is too large, and it is difficult to realize al...

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Problems solved by technology

When welding structural steel, the main problems are: ①The molten droplet transitions in coarse particles, and the splash is large during the welding process; ②The fluidity of the slag is too large, and it is difficult to realize all-position welding; Make the weld narrow and poorly formed; ④ Difficult to remove slag; ⑤ In order to ensure the welding quality, the amount of marble added is usually reduced, but the alkalinity of the slag is reduced, and the crack resistance of the weld is poor; ⑥ In order to avoid hydrogen embrittlement, usually Fluorite (the main component is calcium fluoride) is added to remove hydrogen, but the arc atmosphere is deteriorated, and the welding arc is unstable; Poor mechanical properties

But there are the following deficiencies: ① Fluorite and sodium fluorosilicate are added to the flux core, which deteriorates the welding arc. Although the welding arc is stable as recorded in the manual, there is neither theoretical support nor data verification, and the flux cored wire belongs to Non-self-shielded welding wire, CO2 is required for welding 2 Gas protection, in addition to increasing the cost of use, is also easy to mix nitrogen in the air when the protective atmosphere is not good (on the one hand, nitrogen pores are generated, on the other hand, nitrogen enters the deposited metal, reducing its crack resistance), welding processability The degree of improvement is low; ②Al existing in steel slag 2 o 3 When welding with MnO, MnO·A1 will be generated 2 o 3 Spinel-type compounds, they are built on the iron oxide lattice on the surface of the weld metal, which will cause the slag and the weld metal to stick together firmly, making it more difficult to remove the slag; Added in the form of an intermediate alloy, resulting in poor uniformity of the chemical composition of the deposited metal,

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