CN102773629A

CN102773629A - CO2 gas shielded welding wire with excellent welding performance

Info

Publication number: CN102773629A
Application number: CN2012102348462A
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: 2012-11-14
Anticipated expiration: 2032-07-09
Also published as: CN102773629B

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 good 2Gas protecting welding wire

Technical field

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

Background technology

CO ₂Gas protect be welded into low, efficient is high, in the welding of ordinary construction, be used widely.But it is bad that its major defect is a welding technological properties, except that spatter greatly, the appearance of weld condition of poor also appears easily, promptly the face of weld ripple is big, weld seam the ratio of width to height is less, exists higher stress to concentrate at welding toe, even forms the toe of weld defective.CO commonly used at present ₂Welding wire is H08Mn2Si and AWS ER70S-6, even ER70S-G, all has such problem to some extent.

Though above problem exists always, the effort of process industry also has certain improvement, because requiring of modern Welding Structure and metallic article butt welded seam quality is increasingly high, welding technological properties such as butt welded seam shaping are had higher requirement.Under welding condition commonly used; The ratio of width to height of present welding wire weld seam has reached more than 4.0, but protects occasions such as weldering at plate sheet welding, quick gas, and such the ratio of width to height is still not enough; Be difficult to obtain qualified weld seam, and the improvement of spatter also has very big potentiality.

In China, the butt welded seam Mechanical Properties is more, and most patent is a main target to improve weld strength and toughness all, and to less such as the research of processing performances 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] studied homemade active welding wire in great detail to CO ₂The influence of gas shielded arc welding.It uses activating agent that the spatter rate is reduced greatly, and weld penetration increases, molten wide increase, and depth-to-width ratio increases, and molten drop is with the fine grained transition.Being added in of activating agent significantly increased CO when having reduced the effective ionization voltage of mist ₂The conductive capability of electric arc increases arc energy density, thereby makes the droplet transfer mode under the medium current become the fine grained transition by the bulky grain transition; The variation of appearance of weld is the result of electric arc contraction and surface tension variations double action.But this method also can only make the ratio of width to height of weld seam reach about 4.15, and the method inconvenience of surface applied activating agent is also unstable.

CO ₂When gas is protected welding, CO ₂Strong oxidation reaction will take place with deoxidant element Si, Mn and other reactive alloys element in the welding wire in gas; Form the oxide of Mn, Si, Ti, Al etc.; These oxides will be overflowed from the weld seam motlten metal, form the very thin welding slag of one deck at face of weld.The chemical composition of weld seam motlten metal and welding slag composition will directly influence molten metal flow property like this, thereby influence the shaping of weld seam.When the motlten metal flowability was better, weld seam the ratio of width to height was bigger, and appearance of weld is better.Spatter took place under effect of 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 the steel, the weld seam molten iron is mobile to be increased, and it is more level and smooth that face of weld becomes, and weld seam the ratio of width to height increases.Therefore through the chemical composition that changes welding wire one of approach that improves the welding wire welding technological properties.

Summary of the invention

It is bad that the present invention will solve existing gas protecting welding wire welding technological properties; Have that spatter is big, the problem of appearance of weld difference, it is open and flat to provide a kind of single-pass welding to be shaped, the ratio of width to height reach 5.5 and more than; The face of weld ripple is tiny; It is good to be shaped, and it is little to splash, and is applicable to that opposite joint is formed with the CO of 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 good 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 unavoidable impurities.

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

Preferably: S:0.046～0.059%.

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

C: the butt welded seam metal has invigoration effect, but at CO ₂Gas is protected in the weldering, is prone to and CO ₂The gas effect generates CO gas, in motlten metal, assembles after-explosion formation and splashes.Take all factors into consideration, scope is 0.05 ~ 0.12% preferable.

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

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

Ti: be active element, with CO ₂The Tiization thing that forms after the gas effect can change the droplet metal surface-active, thereby promotes effective transition of molten drop, and minimizing is splashed.Ti also helps the fine Ti compound of formation in weld seam, refinement weld grain.Its content is 0.10 ~ 0.20%.

S: to be considered to be harmful element to S in the ordinary course of things, but S helps improving molten drop or molten metal surface is active, makes motlten metal be easy to launch, and obtains bigger the ratio of width to height thereby be very beneficial for weld seam.Though S can increase the weld seam hot cracking tendency,, the weld seam fire check often is prone to result from narrow and high single-pass welding, and when weld seam solidified, low-melting Sization thing focused on the center of weld seam and produces fire check.And, be difficult for forming fire check in the weld seam when weld seam when being wide and low.Therefore, as long as S is controlled in the suitable scope, its effect can be fully used.Take all factors into consideration, S content is 0.04 ~ 0.059%.

Als: if require weld seam to have higher toughness, the content of Als should be controlled.But the spatter that experiment showed, of present technique reduces with the increase of Als content.Take all factors into consideration, Als content is 0.02 ~ 0.05%.

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

Description of drawings

The weld seam state diagram of Fig. 1 little heat input welding for the present invention utilizes

Fig. 2 utilizes the weld seam state diagram of little heat input welding for prior art

Fig. 3 utilizes the weld seam state diagram of large-line energy welding for the present invention

Fig. 4 utilizes the weld seam state diagram of large-line energy welding for prior art

The surface quality figure of Fig. 5 little heat input welding for the present invention utilizes

Fig. 6 utilizes the surface quality figure of little heat input welding for prior art.

The specific embodiment

Describe in detail in the face of the present invention down:

Table 1 is the composition value tabulation of various embodiments of the present invention and Comparative Examples;

Table 2 is the soldering test technological parameter;

Table 3 is the welding phenomena tabulation of various embodiments of the present invention and Comparative Examples;

Table 4 is various embodiments of the present invention and Comparative Examples welding wire deposited metal tensile property, sulfide and seam organization tabulation.

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

Its step:

If adopt vacuum metling, carry out according to conventional smelting process, be about to main alloy ferrosilicon and ferromanganese and carry out proportioning, vacuumize energising and add the thermalization steel, add the Al pre-deoxidation, add ferrotianium in refining period.The typical composition of smelting is as shown in table 1.Rolling from Ingot is processed Ф 5.5mm wire rod.If adopt converter smelting, adopt Si iron and Mn and aluminium deoxidation, add Si-Mn, low-carbon Mn-Fe (or metal M n-Fe) etc. behind the stove.Adding a jar interior ferroalloy must be clean, dry.(Ar station) by add ferrotianium and aluminium ingot according to the composition requirement, the step of going forward side by side is made into branch when refining.The content of control N does not have other specific (special) requirements to smelting process, and continuous casting becomes 200 * 200 (mm) square billet, and billet rolling is become Ф 5.5mm wire rod.What present technique embodiment adopted is that the 50kg vacuum drying oven is smelted, but is not limited in vacuum drying oven.

Billet rolling is become Ф 5.5mm wire rod.Through peel off, pickling, be drawn to Ф 1.2 the silk, Electroless copper is after pressing mold is processed welding wire.Adopt the test welding wire to carry out the CO2 welding procedure test, in the enterprising windrow weldering of the thick flat board of 10mm.

The composition value tabulation of table 1 various embodiments of the present invention and Comparative Examples

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)
				Technology 1	260	27	28
Technology 2	340	32	32

Table 3 CO2 postwelding outward appearance is described

The physicochemical property assay tabulation of table 4 various embodiments of the present invention and Comparative Examples

Can find out that from each subordinate list and accompanying drawing welding wire welding technological properties of the present invention improves fairly obvious, weld seam has bigger the ratio of width to height, and spatter is less.Weld seam tensile strength reaches 520 ~ 550MPa, and percentage elongation is also higher.Though welding wire contains higher S, the sulphide inculsion in the weld seam still is 0 grade, and metallographic structure is acicular ferrite+pro-eutectoid ferrite.In other words, present technique is when welding technological properties obtains obviously to improve, and other performance is still suitable with existing welding wire, thereby overall performance obviously improves.

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

The used alloy system of welding wire of the present invention is reasonable, and wire rod smelts, rolling and drawing welding wire technology realizes easily.Can adopt converter or electric furnace steel making, billet continuous casting, the rolling dish circle of wire rod rolling factory during batch process, produce the copper plating soldering wire of required specification then in welding wire factory.

Claims

1. CO that welding performance is good 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 unavoidable impurities.