Rutile type flux-cored wire with yield strength exceeding 890 MPa

Abstract

A rutile type flux-cored wire with the yield strength exceeding 890 MPa is composed of a steel belt wrapping a flux core and the flux core filling the steel belt. The flux core comprises, by weight, 0.03%-0.09% of C, 0.3%-0.8% of Si, 1.2%-2.2% of Mn, 0.5%-1.5% of Ni, 1.0%-3.5% of Co, 0.020%-0.045% of Ta, 0.2%-0.5% of rare earth alloy, 2.0%-4.0% of TiO2, 0.2%-0.5% of SiO2, 1.0%-3.0% of ZrO2, 0.2%-0.4% of K2O, and the balance Fe and other inevitable impurities. The welding wire adopts 80% Ar + 20% CO2 mixed gas for shielded welding, and has the characteristics that the yield strength of weld metal exceeds 890 MPa, the low-temperature impact toughness is larger than 47 J at the temperature of -40 DEG C, diffusible hydrogen is smaller than 2 ml / 100 g, the welding arc is stable, and the all-position welding manufacturability is excellent.

Description

technical field [0001] The invention relates to the field of welding materials, in particular to a rutile flux-cored welding wire with a yield strength exceeding 890 MPa. Background technique [0002] With the enlargement of engineering equipment, the problem of increasing the structural weight caused by increasing the wall thickness and increasing the bearing capacity is becoming more and more prominent. Improving the strength of materials is an important way to reduce the weight of equipment. The development of high-end manufacturing The demand for ultra-high-strength steel is increasing, and low-alloy steel with a yield strength exceeding 890MPa, as a typical ultra-high-strength steel, has begun to be applied in batches. [0003] A breakthrough in the key technology of ultra-high-strength steel welding with a yield strength exceeding 890 MPa can effectively control the construction quality and precision of large-scale engineering equipment, reduce weight, save costs, and ...

AI Technical Summary

Problems solved by technology

However, due to its high content of diffusible hydrogen, it is easy to produce welding cold cracks and poor mechanical properties, especially low-temperature toughness, which affects its large-scale promotion and use in high-strength steel welding, especially the welding of ultra-high-strength steel with a strength exceeding 890MPa.

[0005] CN 101323057A discloses a patent for a metal powder cored flux-cored welding wire with a yield strength exceeding 690MPa. This welding wire cannot meet the requirements of all-position welding, and its strength cannot meet the requirements of 890MPa steel welding

[0006] CN 110076477 A, discloses a metal powder cored wire with a multi-pass welding deposited metal to obtain a multi-phase split microstructure and high strength and toughness. The maximum yield strength of the weld metal can only reach 860MPa, and it cannot meet the requirements of all-position welding

[0007] Patent application number 20150378935.8 and publication number CN 14959748A disclose a low-temperature high-strength steel flux-cored welding wire for marine engineering. The yield strength is about 500MPa and the tensile strength is less than 670MPa, which is difficult to meet the welding requirements of 890MPa steel.

[0008] CN 110936060 A The present invention discloses a basic high-strength steel flux-cored welding wire, the highest yield strength of which is only 797MPa, and the basic flux-cored welding wire has the problem of poor welding processability in all positions

[0009] Through the search of existing patents, there is currently no equal-strength matching rutile flux-cored wire suitable for welding low-alloy steels with a yield strength exceeding 890MPa and excellent all-position welding performance.

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