CN102029481A

CN102029481A - Gas shielded welding wire with higher weather resistance

Info

Publication number: CN102029481A
Application number: CN2009101877819A
Authority: CN
Inventors: 吕冬; 付魁军; 白喜峰; 王佳骥; 及玉梅; 刘芳芳; 孙文东
Original assignee: Angang Steel Co Ltd
Current assignee: Angang Steel Co Ltd
Priority date: 2009-09-30
Filing date: 2009-09-30
Publication date: 2011-04-27

Abstract

The invention discloses a gas shielded welding wire with higher weather resistance, which is characterized by comprising the following chemical components by weight percent: 0.03%-0.08% of C, 0.3%-0.7% of Si, 1.3%-1.6% of Mn, less than or equal to 0.015% of S, less than or equal to 0.02% of P, 0.2%-0.5% of Cu, 0.4%-0.8% of Cr, 0.2%-1.0% of Ni, 0.03%-0.1% of Ti and the balance of iron and inevitable impurities, wherein the ratio of Cr to Ni is controlled at 2-3, and the ratio of Ni to Cu is controlled at 0.5-2. The deposited metal and welding joint of the welding wire provided by the invention have good mechanical properties and corrosion resistance. The tensile strength of the deposited metal is greater than 550MPa, and the impact toughness of the deposited metal at the temperature of -40 DEG C is more than 60J. The welding wire has wide welding parameter regulating range, stable welding processes and beautiful formed welding seams and is suitable for all-position welding.

Description

A kind of gas protecting welding wire that has than high-weatherability

Technical field

The invention belongs to metal material field, particularly a kind of yield strength at 450MPa, have gas protecting welding wire than high-weatherability.

Background technology

Along with fast growth of national economy, steel and welding material with weatherability have obtained in fields such as rolling stock, bridge framework and building structure using widely.Steel and welding material not only require to have the favorable mechanical performance, also need both decay resistances approaching.From the long-term use of structure, find, the corrosion resistance mismatch problem of steel and welding material is very outstanding, particularly the fluctuation of the corrosion resistance of welding material is bigger, be subjected to the corrosiveness of atmospheric environment, part welding point position is because of corrosiveness attenuate gradually, and intensity reduces security and descends.Therefore, the decay resistance of raising welding wire is significant to safety of structure.Facts have proved, in welding wire, add elements such as Ni, Cr, Cu, Mo, Als, RE, can obviously improve the decay resistance of welding wire.The present invention sum up the relation of alloying element and deposited metal corrosion rate, and then it is higher to develop a kind of corrosion resistance, the gas protecting welding wire that comprehensive mechanical property is good by adjusting the alloying element in the welding wire.

" high-intensity railway vehicle Weather resistance steel argon-rich gas shielded welding wire " patent that the disclosed Hubei Houwang Welding Material Co., Ltd. of existing corrosion-resistant welding wire such as Chinese patent application number: 200810047484.x proposes.Its composition (mass percent) is as follows: C 0.05%～0.10%, Si 0.3%～0.5%, Mn 1.2%～1.45%, S≤0.015%, P≤0.015%, Cu 0.2%～0.35%, Cr 0.3%～0.7%, Ni 0.2%～0.6%, surplus is iron and unavoidable impurities.

" weather-proof gas protecting welding wire " patent that the disclosed Baoshan Iron and Steel Company of Chinese patent application numbers 200310108200.0 group proposes.Its composition (mass percent) is as follows: C≤0.1%, Si≤0.6%, Mn1.2%～1.6%, S≤0.030%, P≤0.030%, Cu 0.1%～0.6%, Cr0.3%～0.9%, Ni0.2%～0.6%, Ti 0.03%～0.06%, surplus is an iron.

" the high weather-proof gas shield welding wire of high-intensity high-tenacity " patent that the disclosed wuhan iron ﹠ steel croup co. of Chinese patent application 200410013357.x company proposes, its composition (mass percent) is as follows: C 0.04%～0.12%, Si 0.4%～0.8%, Mn 1.4%～2.0%, S≤0.015%, P≤0.02%, Cu 0.3%～0.5%, Cr0.2%～0.5%, Ni 0.4%～1.0%, Ti 0.06%～0.2%, B 0.002%～0.0079%, ALs≤0.02% surplus are iron and unavoidable impurities.

Above patent is weather-proof gas shield welding wire, has added elements such as Cr, Ni, Cu in the welding wire, has certain decay resistance.But, the composition range of elements such as Cr, Ni, Cu has only been proposed in the patent, the proportion relation of each element is not proposed.Studies show that when elements such as Cr, Ni, Cu had different proportion relations, the decay resistance of welding wire had more different.The reasonable proportioning relation can improve the decay resistance of welding wire more than 10%.Corrosion-resistant gas shield welding wire has in the market demonstrated the shortcoming of corrosion resistance deficiency in the actual use of rolling stock.Therefore, the corrosion resistance of raising welding wire has huge realistic meaning.

Summary of the invention

The object of the present invention is to provide a kind of highly corrosion resistant, high tenacity, high-intensity gas protecting welding wire.Mainly be applicable to have the weatherability requirement, yield strength is in the gas shield welding of 450MPa grade steel plate.Welding wire deposited metal yield strength is greater than 450MPa, and impact absorbing energy is greater than 60J under-40 ℃ of conditions.

A kind of gas protecting welding wire that has than high-weatherability of the present invention; the mass percent of its chemical composition is: C 0.03%～0.08%, Si 0.3%～0.7%, Mn 1.3%～1.6%, S≤0.015%, P≤0.02%, Cu 0.2%～0.5%, Cr 0.4%～0.8%, Ni 0.2%～1.0%, Ti 0.03%～0.1%, all the other are iron and unavoidable impurities.And the Cr/Ni proportion control is between 2～3, and the Ni/Cu proportion control is between 0.5～2.

Main component design considerations of the present invention is described below:

C is as the effective element that improves intensity, the weld metal yield strength can not reach the 450MPa requirement when C content is lower than 0.03%, and when content surpassed 0.08%, the decay resistance of weld metal reduced, and the weld seam low-temperature flexibility is relatively poor, and the crack sensitivity of weld seam increases.In order to guarantee that weld seam has higher decay resistance, C content preferable range is between 0.04%～0.08%.

Si, Mn are important deoxidant elements, and the ratio of adjusting two elements in the welding wire can obtain good welding technological properties.Simultaneously, two elements have significant contribution to improving weld metal intensity.

The Ti element can improve the welding procedure of welding wire, carries out the transition to the oxide or the nitride of the Ti element formation of weld seam, can promote that acicular ferrite forms in the weld seam, improves seam organization, improves welding seam toughness.

The Cr element is the essential element that improves the welding wire corrosion resistance, and its preferable range is 0.5%～0.8%.After content surpasses 0.8%, the low-temperature flexibility severe exacerbation of weld metal.Be lower than the decay resistance deficiency of 0.4% weld seam.

The Ni element has corrosion resistance preferably on the one hand, can improve the welding wire low-temperature flexibility on the other hand.Welding wire wire rod hardness height when Ni content is higher, intensity are big, have improved the welding wire production cost, the toughness and the rotproofness deficiency of welding wire when content is low.For guaranteeing the ratio between the Cr-Ni-Cu, the preferable range of Ni is 0.25%～0.5%.

The Cu element also has corrosion resistance preferably, and after Cu content in the welding wire surpassed 0.5%, Cu was with precipitation strength in the weld seam, and the low-temperature flexibility of butt welded seam is unfavorable.

Corrosion-resistant gas of the present invention protection welding wire, its Cr/Ni proportion control are between 2～3, and the Ni/Cu proportion control is between 0.5～2.0 the time, the impact flexibility of welding wire deposited metal and decay resistance the best.

S, P are harmful element, and its content is low more good more.

Welding wire of the present invention is smelted production process and process and common gas shield welding wire indifference.

The present invention compared with prior art has following beneficial effect:

1, welding wire deposited metal of the present invention and welding point have good mechanical performance and decay resistance.Deposited metal tensile strength is greater than 550MPa, and-40 ℃ of impact flexibility are more than 60J.

2, welding wire welding parameter area of the present invention adjusting is wide, and welding procedure is stable, and appearance of weld is attractive in appearance, is fit to all-position welding.

The specific embodiment

Adopt the 200kg vacuum drying oven to smelt welding wire steel, rolling through wire rod, operations such as drawing welding wire are made into the finished product welding wire that diameter is 1.2mm, welding wire surface copper facing.Chemical composition sees Table 1.Welding deposited metal test plate (panel) welding conditions are: welding current: 220～250A, and weldingvoltage: 26～27V, speed of welding: 5.6mm/s, protective gas are 80%Ar+20%CO ₂, control interlayer temperature≤150 ℃.Welding wire corrosion test sample is taken from the deposited metal of welding wire, 3 on parallel sample, and 35 ± 1 ℃ of test temperatures, the corrosion test solution: concentration is 5% NaCl.Deposited metal mechanical property and corrosive nature see Table 2.

Table 1 embodiment chemical composition (Wt%)

Table 2 welding wire deposited metal mechanical property and salt spray test result

* the impact flexibility data of deposited metal are the mean value of five samples.

Big and the 60J of corrosion-resistant solid welding wire deposited metal-40 ℃ impact flexibility of the present invention is fit to and sector applications such as rolling stock, bridge, building.

Claims

1. gas protecting welding wire that has than high-weatherability; the mass percent that it is characterized in that the welding wire chemical composition is: C 0.03%～0.08%, Si 0.3%～0.7%, Mn 1.3%～1.6%, S≤0.015%, P≤0.02%, Cu 0.2%～0.5%, Cr 0.4%～0.8%, Ni 0.2%～1.0%, Ti 0.03%～0.1%; all the other are iron and unavoidable impurities; and the Cr/Ni proportion control is between 2～3, and the Ni/Cu proportion control is between 0.5～2.

2. a kind of gas protecting welding wire that has than high-weatherability according to claim 1 is characterized in that the Cr/Ni proportion control between 2.0～2.5, and the Ni/Cu proportion control is between 1.1～1.6.