High-strength and high-toughness metal powder type flux-cored wire with no need of being pre-heated before welded

Abstract

The invention provides a high-strength and high-toughness metal powder type flux-cored wire with no need of being pre-heated before welded. Steel skin is 79-84% of a total weight of a welding wire and a flux core is 16-21% of the total weight of the welding wire. The steel skin is manufactured by using a cold rolling carbon steel strip and comprises the following components: 0.02-0.055% of C, 0.005-0.0085% of Si, 0.15-0.35% of Mn and the balance of iron; and the flux core comprises the following components: 12-18% of nickel powder, 2-4% of manganese powder, 3-7% of silicon iron, 2-6% of ferro-molybdenum, 0.8-2.5% of ferrotitanium, 1-5% of mid-carbon ferromanganese, 0.8-2.5% of potassium fluosilicate and rear earth oxide in sum, and the balance of iron powder. The flux-cored wire provided by the invention has the advantages of good welding process, high melting efficiency and less slag quantity; the yield strength of deposited metal can be more than 590 MPa; the impact rigidity at a temperature of -50 DEG C can be more than 70J; and the diffusible hydrogen is in an ultralow hydrogen level.

Description

technical field [0001] The invention relates to a gas shielded welding welding material, in particular to a high-strength and toughness metal powder type flux-cored welding wire which does not need to be preheated before welding. Background technique [0002] Flux-cored welding wire has been widely used in the construction of steel structures such as ships, bridges and offshore platforms due to its advantages of good welding processability and high welding efficiency. With the development of society, the strength level of the applied structural steel is getting higher and higher, and the strength of the supporting flux-cored welding wire is also increased, which brings about the problem of crack sensitivity of high-strength weld metal becoming increasingly prominent. At present, there are few high-strength flux-cored wires that match the structural steel with a yield strength greater than 590MPa, and preheating measures are required before welding, and sometimes even post-he...

AI Technical Summary

Problems solved by technology

[0003] 1) Chinese Patent Application No. 200610014242.1 is a kind of low-hydrogen high-toughness acidic flux-cored welding wire. The flux-cored welding wire involved is slag-type rather than metal-powder type. Strength requirements for structural steel with yield strength greater than 590MPa

[0004] 2) Chinese patent application number 201110131892.5 is an acidic flux-cored welding wire for ultra-low hydrogen and low-temperature steel. The flux-cored welding wire involved is slag type rather than metal powder type. Strength greater than 590MPa structural steel strength does not match

[0006] Search the current existing welding wire patents, there is no flux-cored welding wire that does not need to be preheated before welding and matches the structural steel with a yield strength greater than 590MPa

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