CN102773629B

CN102773629B - CO2 gas shielded welding wire with excellent welding performance

Info

Publication number: CN102773629B
Application number: CN201210234846.2A
Authority: CN
Inventors: 黄治军; 李立军; 胡家国; 钟如涛; 方要治
Original assignee: Wuhan Iron and Steel Group Corp
Current assignee: Wuhan Iron and Steel Co Ltd
Priority date: 2012-07-09
Filing date: 2012-07-09
Publication date: 2015-06-17
Anticipated expiration: 2032-07-09
Also published as: CN102773629A

Abstract

The invention relates to a CO2 gas shielded welding wire with excellent welding performance, which comprises the components by weight percent: 0.05-0.12% of C, 0.70-1.10% of Si, 1.60-1.90% of Mn, less than or equal to 0.020% of P, 0.04-0.59% of S, 0.10-0.20% of Ti, 0.02-0.05% of Als and the balance of Fe and unavoidable impurities. The CO2 gas shielded welding wire not only is stable and reliable in a welding wire steel smelting technology and a rolling and drawing technology, but also is open and flat in single-pass weld joint formation; a weld joint has the aspect ratio of 5.5 and above, is fine in surface waviness, good in formation and small in splashing; and the CO2 gas shielded welding wire is especially suitable for welding a workpiece with high requirement for weld joint formation, and has better application prospect.

Description

The CO that a kind of welding performance is excellent 2gas protecting welding wire

Technical field

The present invention relates to a kind of welding wire of metal solder, specifically belong to the CO that a kind of welding performance is excellent ₂gas protecting welding wire.

Background technology

CO ₂gas protect be welded into low, efficiency is high, be used widely in the welding of ordinary construction.But it is bad that its major defect is welding technological properties, except spatter greatly except, also easily occur the situation that appearance of weld is bad, namely face of weld ripple is large, and weld seam the ratio of width to height is less, there is higher stress and concentrates, even form toe of weld defect at welding toe.CO conventional at present ₂welding wire is H08Mn2Si and AWS ER70S-6, even ER70S-G, there is such problem all to some extent.

Although above problem exists always, the effort through industry also has certain improvement, and because the requirement of modern Welding Structure and metallic article butt welded seam quality is more and more higher, the welding technological properties such as butt welded seam shaping are had higher requirement.Under conventional welding condition, the ratio of width to height of present welding wire weld seam reaches more than 4.0, but protects the occasions such as weldering at plate sheet welding, quick air, and such the ratio of width to height is still inadequate, be difficult to obtain qualified weld seam, and the improvement of spatter also has very large potentiality.

In China, the research of butt welded seam mechanical property is more, and most patent is all to improve weld strength and toughness for main target, and less to the research of the processing performances such as such as weld seam the ratio of width to height, spatter.[Yuan Yulan, Wang Xibao, Zhu Dongmei etc., activation CO ₂the research of gas shielded arc welding. welded tube .2006 (1) .-35-39] study homemade active welding wire in great detail to CO ₂the impact of gas shielded arc welding.It uses activating agent that spatter rate can be made greatly to reduce, and weld penetration increases, and molten wide increase, depth-to-width ratio increases, and molten drop is with fine grained transition.CO is significantly increased while being added in of activating agent reduces the effective ionization voltage of mist ₂the conductive capability of electric arc, makes arc energy density increase, thus the droplet transfer mode under making medium current becomes fine grained transition by bulky grain transition; The change of appearance of weld is the result of arc constriction and surface tension variations double action.But the method also can only make the ratio of width to height of weld seam reach about 4.15, and the method inconvenience of surface application activating agent is also unstable.

CO ₂when gas protects welding, CO ₂strong oxidation reaction will be there is in gas with deoxidant element Si, the Mn in welding wire and other reactive alloys element, form the oxide of Mn, Si, Ti, Al etc., these oxides will be overflowed from weld seam motlten metal, form the welding slag of thin layer at face of weld.The chemical composition of such weld seam motlten metal and welding slag composition directly will affect the mobility of motlten metal, thus affect the shaping of weld seam.When molten metal flow is better, weld seam the ratio of width to height is comparatively large, and appearance of weld is better.Spatter occurs under the effect of the factors such as electric arc back-pressure and chemical reaction when the droplet transfer.In certain content range, along with the increase of active component oxygen, sulfur content in steel, weld seam molten iron flow increases, and face of weld becomes more level and smooth, and weld seam the ratio of width to height increases.Therefore be one of approach of raising welding wire welding technological properties by the chemical composition of change welding wire.

Summary of the invention

It is bad that the present invention will solve existing gas protecting welding wire welding technological properties; there is the problem that spatter is large, appearance of weld is poor; a kind of single-pass welding is provided to be shaped open and flat; the ratio of width to height reach 5.5 and more than; face of weld ripple is tiny; be shaped good, splash little, and be applicable to the CO that opposite joint is formed with the workpiece welding of high request ₂gas protecting welding wire.

Realize the measure of above-mentioned purpose:

The CO that a kind of welding performance is excellent ₂gas protecting welding wire, its component and weight percent content are: C:0.05 ~ 0.12%, Si:0.70 ~ 1.10%; Mn:1.60 ~ 1.90%, P≤0.020%, S:0.04 ~ 0.059%; Ti:0.10 ~ 0.20%, Als:0.02 ~ 0.05%, all the other are Fe and inevitable impurity.

Preferred: C:0.05 ~ 0.10%; Most preferred: C:0.05 ~ 0.08%.

Preferred: S:0.046 ~ 0.059%.

The effect of each component and main technique and the reason of control in the present invention:

C: Resistance of Weld Metal has invigoration effect, but at CO ₂gas is protected in weldering, easy and CO ₂gas effect generates CO gas, assembles after-explosion in the molten metal and forms splashing.Consider, scope is 0.05 ~ 0.12% better.

Si: at CO ₂gas is protected in weldering has stronger deoxidation, and can also increase weld strength, be CO ₂indispensable alloying element in gas shielded arc welding.But the toughness of weld seam can be affected when Si content is too high in weld seam.The weight percent content 0.70 ~ 1.10% of Si in welding wire.

Mn: the effective element being weld seam Strengthening and Toughening, is also deoxidant element simultaneously, can prevents the formation of the iron sulfide causing fire check.In welding wire, Mn content is 1.60 ~ 1.90%.

Ti: be comparatively active element, with CO ₂the Ti compound formed after gas effect can change droplet metal surface-active, thus promotes effective transition of molten drop, reduces and splashes.Ti also helps and in weld seam, forms fine Ti compound, refinement weld grain.Its content is 0.10 ~ 0.20%.

S: S is considered to be harmful element in the ordinary course of things, but S to be conducive to improving molten drop or molten metal surface active, make motlten metal be easy to launch, thus be very beneficial for weld seam and obtain larger the ratio of width to height.Although S can increase weld seam hot cracking tendency, weld seam fire check often easily results from narrow and high single-pass welding, and when weld seam solidifies, the S compound of low melting point focuses on the center of weld seam and produces fire check.And when weld seam is wide and low, in weld seam, not easily form fire check.Therefore, as long as controlled by S in suitable scope, its effect can be fully used.Consider, S content is 0.04 ~ 0.059%.

Als: if require that weld seam has higher toughness, the content of Als should control.But the experiment of this technology proves, spatter reduces with the increase of Als content.Consider, Als content is 0.02 ~ 0.05%.

The present invention compared with prior art, not only welding wire steel smelting process, rolling and drawing process are reliable and stable, more mainly single-pass welding is shaped open and flat, the ratio of width to height reach 5.5 and more than, face of weld ripple is tiny, is shaped good, splashes little, and being specially adapted to the workpiece welding that opposite joint is formed with high request, it has good application prospect.

Accompanying drawing explanation

Fig. 1 is the weld seam state diagram that the present invention utilizes little heat input to weld

Fig. 2 is the weld seam state diagram that prior art utilizes little heat input to weld

Fig. 3 is the weld seam state diagram that the present invention utilizes Large Heat Input Welding

Fig. 4 is the weld seam state diagram that prior art utilizes Large Heat Input Welding

Fig. 5 is the surface quality figure that the present invention utilizes little heat input and welds

Fig. 6 is the surface quality figure that prior art utilizes little heat input and welds.

Detailed description of the invention

Below the present invention is described in detail:

Table 1 is the composition value list of various embodiments of the present invention and comparative example;

Table 2 is soldering test technological parameter;

Table 3 is the welding phenomena list of various embodiments of the present invention and comparative example;

Table 4 is various embodiments of the present invention and comparative example welding wire deposited metal tensile property, sulfide and seam organization list.

Various embodiments of the present invention are produced according to following conventional steps:

Its step:

According to vacuum metling, conveniently smelting process carries out, and carries out proportioning, vacuumizes electrified regulation steel, add Al pre-deoxidation, add ferrotianium in refining period by major alloy ferrosilicon and ferromanganese.The typical composition of smelting is as shown in table 1.Rolling from Ingot is made Ф 5.5mm wire rod.According to converter smelting, adopt Si iron and Mn and aluminium deoxidation, after stove, add Si-Mn, low-carbon Mn-Fe(or metal M n-Fe) etc.The ferroalloy added in tank must be clean, dry.When refining, (Ar station) adds ferrotianium and aluminium ingot by according to component requirements, a step adjusting component of going forward side by side.The content of control N, to smelting process without other particular/special requirement, continuous casting becomes 200 × 200 (mm) square billet, and billet rolling is become Ф 5.5mm wire rod.What this technical em-bodiments adopted is that 50kg vacuum drying oven is smelted, but is not limited in vacuum drying oven.

Billet rolling is become Ф 5.5mm wire rod.Through peeling off, pickling, being drawn to the silk of Ф 1.2, after Electroless copper, making welding wire through pressing mold.Test welding wire is adopted to carry out CO2 welding procedure test, in the enterprising windrow weldering of the thick flat board of 10mm.

The composition value list of table 1 various embodiments of the present invention and comparative example

Numbering	C	Si	Mn	P	S	Ti	Als
								1	0.07	0.91	1.78	0.015	0.059	0.13	0.031
2	0.05	1.09	1.60	0.010	0.041	0.10	0.039
								3	0.12	0.72	1.88	0.010	0.046	0.17	0.020
4	0.10	0.98	1.70	0.010	0.046	0.17	0.020
								5	0.063	0.83	1.76	0.013	0.048	0.12	0.025
6	0.086	0.94	1.65	0.012	0.055	0.14	0.030
								7	0.098	0.75	1.87	0.012	0.043	0.16	0.035
8	0.11	0.97	1.63	0.011	0.057	0.15	0.026
								Contrast 1	0.08	0.85	1.76	0.011	0.010	0.13	0.010
Contrast 2	0.09	0.90	1.87	0.011	0.015	/	0.005

Table 2 soldering test technological parameter

	Electric current (A)	Voltage (V)	Weldering speed (cm/min)
				Technique 1	260	27	28
Technique 2	340	32	32

Table 3 CO2 postwelding outward appearance describes

The physicochemical property assay list of table 4 various embodiments of the present invention and comparative example

As can be seen from each subordinate list and accompanying drawing, welding wire welding technological properties of the present invention improves fairly obvious, and weld seam has larger the ratio of width to height, and spatter is less.Weld seam tensile strength reaches 520 ~ 550MPa, and percentage elongation is also higher.Although welding wire is containing higher S, the sulphide inculsion in weld seam is still 0 grade, and metallographic structure is acicular ferrite+pro-eutectoid ferrite.In other words, this technology is while welding technological properties acquisition significantly improves, and other performance is still suitable with existing welding wire, and thus overall performance significantly improves.

It can also be seen that from Fig. 1 ~ 6, welding wire of the present invention is compared with contrast welding wire, and its feature is except wide and open and flat, and the fusion penetration of weld seam is also more shallow.The energy equal weld seam area is wasted on mother metal reduces, and that also can reduce mother metal answers shape and stress, economize energy, material and human cost, and welding quality improves.

Welding wire of the present invention alloy system used is reasonable, and wire rod smelting, rolling and drawing welding wire technique easily realize.Converter or electric furnace steel making, billet continuous casting, wire rod rolling factory rolling dish circle can be adopted during batch production, then produce the copper plating soldering wire of required specification in welding wire production factory.

Claims

1. the CO that a welding performance is excellent ₂gas protecting welding wire, its component and weight percent content are: C:0.05 ~ 0.12%, Si:0.91 ~ 0.98%; Mn:1.70 ~ 1.90%, P≤0.020%, S:0.055 ~ 0.059%; Ti:0.16 ~ 0.20%, Als:0.026 ~ 0.031%, all the other are Fe and inevitable impurity.