CN109434322A

CN109434322A - A kind of flux-cored wire and preparation method thereof

Info

Publication number: CN109434322A
Application number: CN201811434102.9A
Authority: CN
Inventors: 徐进; 郑燕华
Original assignee: Dongguan University of Technology
Current assignee: Dongguan University of Technology
Priority date: 2018-11-28
Filing date: 2018-11-28
Publication date: 2019-03-08

Abstract

A kind of flux-cored wire and preparation method thereof, including core wire and medicine core, the chemical component of core wire, by weight percentage: C≤0.2%, Mn≤0.3-0.8%, Si≤0.03, Cr≤4-8%, Ni≤0.5%, Cu≤0.4%, S≤0.005%, P≤0.006%, surplus Fe；Drug core component is based on its weight percent: fluoride 30-50%, marble 8-20%, magnesite powder 2-10%, ferrochrome 30-50%, manganese iron 4-9%, ferrosilicon 4-8%, graphite 4-7%, vanadium iron 2-5%, iron powder are surplus；The present invention overcomes prior art welding wire in vertical downward weldering, horizontal position welding or overhead welding, molten pool metal and slag drop down under occurring under the effect of gravity, it is difficult to transition and enters molten bath, cause built-up welding constructional difficulties, processing performance is poor, even prevent welding bead from forming, and by increasing flux-cored wire diameter, improves cladding speed.

Description

A kind of flux-cored wire and preparation method thereof

Technical field

The present invention relates to a kind of wlding of built-up welding, in particular to a kind of flux-cored wire and preparation method thereof.

Background technique

Originate from the U.S. within flux-cored wire 1954, is to grow up on the basis of the flux-cored electrode tubular electrode twenties, due to medicine Core welding wire has arc stability, splashes that small, forming is beautiful, the adjustment of medicine core formula is easy, and can in high volume manufacture and actual welding The superiority of middle continuous use, compared with solid core welding wire, stick electrode, the operating environment of high production efficiency, welder is improved, The comprehensive advantage of flux-cored wire is deeply welcomed by the people, and flux-cored wire is rapidly developed and be widely used in various gold in foreign countries Belong to structure, the manufacturing technology difficulty of flux-cored wire is big, and domestic the relevant technologies and level fall behind, domestic by development in recent years Flux-cored wire industry obtains significant progress, and common flux-cored wire can satisfy domestic demand completely, and export volume is also bigger, but Some extraordinary, high performance flux-cored wires, such as wear-resisting, self-shield welding, electro-gas (enclosed) welding flux-cored wire also need import.

Since the later period eighties, the manufacture and use range of 1.2 ~ 1.6mm gas-shielded flux-cored wire multi items is obtained rapidly It promotes, uses and expand in non-shipbuilding industry, then developed metal powder-cored wire and seamless flux-cored wire, at present medicine core Welding wire is widely used in the manufacture such as building, bridge, chemical industry, metallurgy, electric power and repairs industry.

At present flux-cored wire production line production common flux-cored wire diameter have 1.2mm, 1.4mm, 1.6mm, 2.0mm, 8 kinds of 2.4mm, 2.8mm, 3.2mm, 4.0mm etc., it is widely used in CO2 gas shielded arc welding, submerged-arc welding and open arc welding；Built-up welding medicine core The diameter of welding wire is usually no more than 4.0mm, and there are no document reports for the flux-cored wire of diameter 4.0mm or more.

Self-shield built-up welding is realized by slag-gas-alloying element Combined Protection, relies primarily on gas-forming agent in molten drop formation stages It decomposes, the gas that low-melting-point metal high-temperature gasification generates forms gas hood, prevention air intrusion molten drop；Slag former fusing, plays machine Tool protective effect, stage droplet transfer using deoxidation nitrogen fixation agent absorb controls gold reaction generate oxygen and nitrogen, the molten bath stage mainly according to By flux shielding, it is desirable that slag has good physical property, so that molten bath keeps appropriate shape, is conducive to gas evolution and weld seam Forming, there is presently no document reports to have good self-shield built-up welding slag system that can guarantee weldquality.

Summary of the invention

The present invention overcomes prior art welding wire in vertical downward weldering, horizontal position welding or overhead welding, and molten pool metal and slag can be in gravity Effect is issued to give birth to and is dropped down, it is difficult to transition enters molten bath, causes built-up welding constructional difficulties, and processing performance is poor, or even prevent welding bead from Type, and by increasing flux-cored wire diameter, cladding speed is improved, a kind of flux-cored wire and preparation method thereof is provided.

A kind of large-diameter self-protection flux-cored welding wire for overlaying welding, including core wire and medicine core, the chemical component of core wire, by weight hundred Point than meter: C≤0.2%, Mn≤0.3-0.8%, Si≤0.03, Cr≤4-8%, Ni≤0.5%, Cu≤0.4%, S≤0.005%, P≤ 0.006%, surplus Fe；Drug core component is based on its weight percent: fluoride 30-50%, marble 8-20%, magnesite powder 2- 10%, ferrochrome 30-50%, manganese iron 4-9%, ferrosilicon 4-8%, graphite 4-7%, vanadium iron 2-5%, iron powder are surplus.

Further, fluoride is the combination of one or both of barium fluoride, lithium fluoride.

Further, drug core component are as follows: fluoride 40-50%, marble 10-20%, magnesite powder 7-10%, ferrochrome 30-50%, Manganese iron 4-9%, ferrosilicon 4-8%, graphite 5-7%, vanadium iron 2-5%, iron powder are surplus.

The surface temperature of molten drop when the boiling temperature of most of fluorides is below wire melting, therefore, when built-up welding, is fluorinated Object can gasify in arc region, form dynamic gas cage and cover on welding wire end, play the role of air-isolation；To take into account all positon heap Adaptability is welded, selects fluoride based on BaF2, while adding some fluorites to adjust the viscosity of slag, LiF can not only make Gas, slag making, and have certain stabilising arc and nitrogen fixation.

To realize good self-shield effect, this welding wire slag system has selected a large amount of fluorides, and the common fluorine of flux-cored wire In compound, BaFa can support short arc burning；Meanwhile compared with CaF2, BaF2 ionization energy is small, is conducive to welding arc stablility Property and reduce spatter；In addition, BaF2 also helps the P reduced in welding bead, and then improve mechanical performance.

Carbonate decomposition can discharge CO2, CO, molten drop and molten bath can be protected to encroach on from air, while can also enhance electricity Arc blowing force is conducive to droplet transfer and all positon built-up welding；When this welding wire selects carbonate, its decomposition temperature is mainly considered, if decomposing Temperature is too low, and carbonate can be decomposed prior to wire melting, it will causes gas to escape, or even bursts in welding wire seam crossing； Decomposition temperature is excessively high, cannot play the role of gas making protection.

The common carbonate decomposition temperature of flux-cored wire is lower, and marmorean decomposition temperature be 1310 DEG C, the temperature with 1480 DEG C of the fusing point of steel is very close to and the marble of molten state can improve the wetability of slag, keep slag preferable It is covered on metal surface, but the marble of equal quality, the oxide for decomposing generation does not have, and fluxing effect is smaller, and CaCO3 points The Ca0 that solution generates can increase slag basicity, can improve the physical property of slag, be conducive to hold molten iron when vertical downward built-up welding.

In flux-cored wire, Chang Tianjia graphite realizes self-shield, and graphite is added can realize in advance to a certain extent Deoxidation, but when content is higher, is easy to produce stomata instead；Molten drop has brought part oxygen into during being formed and entering molten bath, The graphite of precedent desoxydation remnants forms CO gas, the evolution speed of CO gas is lower than knot in conjunction with these oxygen are when welding bead solidifies Stomata will be generated when brilliant speed, since graphite additive amount is high to stomata susceptibility, and graphite influences medicinal powder mobility and weldering Silk fill factor.

Therefore, this welding wire does not select to add carbon deoxidation gas making protection with form of graphite；In addition, carbon content in carbon deposited metal Number can have vital influence to tissue morphology therein and distribution, the property of carbide, quantity and performance；Carbon is The element that must add in iron-based abrasion resistant overlaying-welding material can significantly improve the wearability and hardness of deposited metal；But built-up welding is golden Carbon content in category be not it is The more the better, only when carbon content is in a suitable range, can just give full play to its work With.

MgO is mainly added in the form of magnesite powder, and magnesite powder main component is MgO, and content of MgO is generally 85% or more, simultaneously Contain 10% or so CaO；The basicity of slag can be improved in the addition of CaO and MgO, improves the toughness of weld seam to a certain extent； In addition, the viscosity and setting temperature of dystectic magnesia adjustment welding wire slag

Chromium: chromium is transition element, and fusing point is at 1850 DEG C or so；Distribution of the chromium in overlay cladding can form carbonization Object can also be solid-solution in matrix, improve harden ability, hardness, wearability and the corrosion resistance of matrix；In hardfacing alloy, carbon and Chromium is usually to combine to work, and can investigate the influence of Cr/C ratio；The tissue and mechanical property of Cr/C comparison wear-resistant material Can all have a great impact, to be had a huge impact to wearability.

Vanadium: vanadium also belongs to transiting group metal elements, and more a height of 1920 DEG C of fusing point；Vanadium is that strong carbide is formed Element, the fusing point of VC are 1850 DEG C ~ 2730 DEG C, and V and carbon can go into two kinds of stable carbide of VC and V2C, and VC is compared in steel Comparatively ideal carbide hard phase, this is primarily due to, and VC carbide quality is hard, and high-temperature behavior is good, does not allow in case of wear It is easy to crack；VC can form the dispersion-strengtherning of carbide when forming carbide hard phase, have very to the wearability for improving material Important role.

Manganese (Mn), silicon (Si) all have good deoxidizing capacity, and the boiling point of manganese is only 1962K, in the welding process easily Volatilization, form certain density manganese steam in electric arc reaction area, reduce partial pressure of oxygen, play the role of deoxidation early period, manganese into After entering welding bead, it is easy to form soild oxide in conjunction with oxygen, also has effect to later period deoxidation；And Si is more preferable as deoxidizing capacity Element, but the deoxidation products of silicon is not easy to float, and needs to combine with manganese, in a certain range of manganese silicon ratio, forms big The oxidation product of grain low melting point is easy to float, it is therefore desirable to which Si and manganese are carried out combined deoxidation.

A kind of preparation method of flux-cored wire:

(1) selecting wall thickness is 0.4mm, and width is the commercially available H08A steel band of 35mm, and the special equipment utilized is along steel band length direction It is U-shaped that (longitudinal direction), which is rolled into cross section,；

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；

Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder is determined according to deposited metal ingredient and performance requirement；

(3) as needed, can U-shaped grain in medicinal powder among along steel band length direction lay a diameter be 0.8mm, with it is described The isometric steel wire of steel band, steel wire are located at the geometric center of steel band longitudinal cross-section after molding；

(4) medicinal powder will be filled or medicinal powder adds the cross section after steel wire to connect in the form of seaming for the steel band widthwise edge of U-shaped, make medicine Powder or medicinal powder add steel wire to be wrapped in steel band, and formation is surrounded by medicinal powder or medicinal powder adds the steel pipe of steel wire, and by cold rolling tube reducing, obtains Flux-cored wire blank；The diameter of flux-cored wire blank is 12mm, and the width of seaming connecting portion is 0.8mm；

(5) by flux-cored wire blank, diameter 10mm is cold rolled to by the series of rollers on special equipment, cold rolling can be such that medicine core welds Medicinal powder inside silk blank is closely knit；

(6) it is touched by wire drawing, by drawing of the flux-cored wire blank Jing Guo 9.5mm, 9.0mm, 8.5mm, 8.0mm passage after cold rolling It pulls out, tube reducing, its diameter is finally made to reach 8.0mm；

(7) by the resulting flux-cored wire take-up of step (6), coiling disc forming to get built-up welding large-diameter flux-cored wire.

The beneficial effects of the present invention are:

The CaO generated is decomposed by marble and increases slag basicity, can be improved the physical property of slag, is conducive to stand to when built-up welding It holds molten iron and MgO increases viscosity coefficient of dross and setting temperature realizes welding wire all-position welding, marble and fluoride are made Slag, gas-forming agent protect molten drop and molten bath to encroach on from air, and graphite adds carbon deoxidation gas making protection；

Using the measure that steel wire is pressed from both sides in flux-cored wire solve large-diameter flux-cored wire welding current welding wire Latitudinal section it is uneven, Welding technological properties is poor, can not normal weld the technical issues of, so that flux-cored wire diameter is can achieve 8mm or more, improve cladding Speed；The wearability of matrix is improved using alloying element chromium, manganese, vanadium metal simultaneously.

Detailed description of the invention

Fig. 1 is welding process schematic diagram of the present invention.

Fig. 2 is the structure chart of built-up welding welding wire of the present invention.

Specific embodiment

Combined with specific embodiments below, the present invention is furture elucidated；It should be understood that these embodiments are merely to illustrate the present invention Rather than the claimed range of the limitation present invention；It will further be understood that read the content lectured of the present invention it Afterwards, those skilled in the art can make various changes or modification to the present invention, and such equivalent forms are equally fallen within appended by the application Claims limited range.

Built-up welding test plate (panel): Q235 steel plate, plate size are 300mm × 150mm × 12mm, before weldering extremely with sanding machine polishing derusting Expose metallic luster in surface.

Testing equipment: gas shielded and self-shield built-up welding welding use NBG-500x type welding machine, and submerged arc overlay welding uses ZD5- 1250E automatic submerged-arc welding machine, track automatic submerged arc welding machine.

The method that test uses arc welding, built-up welding are NBG-500x type welding machine with welding machine, and welding gun uses recirculated water cooling.

Gas is protected and self-insurance submerged-arc welding test uses flux-cored wire diameter for 8mm, and protective gas is 82%Ar+18%CO2 mixing Gas, gas flow 16L/min.

Submerged-arc welding uses automatic submerged arc welding machine, uses ESAB OKFLUX10.71 solder flux.

Built-up welding is multi-pass welding, and every layer 4 has 4 layers of built-up welding altogether, removes the alloy-layer for taking the 4th layer heap to weld when sample, such energy Utmostly overcome the diluting effect of base material；Per pass postwelding carries out percussion scarfing cinder, controls temperature between road.

Embodiment one

A kind of preparation method of flux-cored wire:

(1) selecting wall thickness is 0.4mm, and width is the commercially available H08A steel band of 35mm, and the special equipment utilized is along steel band length direction Being rolled into cross section is U-shaped；

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality, primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Point and performance requirement determine, drug core component are as follows: fluoride 40-50%, marble 10-20%, magnesite powder 7-10%, ferrochrome 30-50%, Manganese iron 4-9%, ferrosilicon 4-8%, graphite 5-7%, vanadium iron 2-5%, iron powder are surplus；

Welding condition are as follows: weldingvoltage 20-30V, welding current 200-300A, speed of welding 20-30m/h.

With wire cutting machine tool from interception surfacing layer metal, deposited metal surface is polished.

Test uses ball-mill damage machine.

Wear test process: it is dried up after the sample completely taken with acetone rinsing with hair dryer, on electronic analytical balance Its weight is weighed, weight Mo before abrasion is measured；Then after carrying out wear test, acetone rinsing sample is equally used, and dry up, again Measure weight Mo after sample is worn；Calculate wear weight loss 0.0054g；All positon built-up welding slag can hold molten iron；Self-shield Effect: welding bead pore-free, self-shield excellent effect.

Embodiment two

A kind of preparation method of flux-cored wire:

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Divide and performance requirement determines；Drug core component are as follows: fluoride 30-40%, marble 8-15%, magnesite powder 2-5%, ferrochrome 30-40%, manganese Iron 4-9%, ferrosilicon 4-8%, graphite 5-7%, vanadium iron 2-5%, iron powder are surplus；

Test uses ball-mill damage machine.

Wear test process: it is dried up after the sample completely taken with acetone rinsing with hair dryer, on electronic analytical balance Its weight is weighed, weight Mo before abrasion is measured；Then after carrying out wear test, acetone rinsing sample is equally used, and dry up, again Measure weight Mo after sample is worn；Calculate wear weight loss 0.0061g；All positon built-up welding slag can hold molten iron；Self-shield Effect: welding bead pore-free, self-shield excellent effect.

Embodiment three

A kind of preparation method of flux-cored wire:

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Divide and performance requirement determines；Drug core component are as follows: fluoride 30-50%, marble 8-15%, magnesite powder 2-5%, ferrochrome 35-40%, manganese Iron 4-9%, ferrosilicon 4-6%, graphite 6-7%, vanadium iron 2-3%, iron powder are surplus；

Test uses ball-mill damage machine.

Wear test process: it is dried up after the sample completely taken with acetone rinsing with hair dryer, on electronic analytical balance Its weight is weighed, weight Mo before abrasion is measured；Then after carrying out wear test, acetone rinsing sample is equally used, and dry up, again Measure weight Mo after sample is worn；Calculate wear weight loss 0.0064g；All positon built-up welding slag can hold molten iron；Self-shield Effect: welding bead pore-free, self-shield excellent effect.

Example IV

A kind of preparation method of flux-cored wire:

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Divide and performance requirement determines；Drug core component are as follows: fluoride 30-45%, marble 8-14%, magnesite powder 2-3%, ferrochrome 35-40%, manganese Iron 4-8%, ferrosilicon 4-6%, graphite 5-7%, vanadium iron 2-3%, iron powder are surplus；

Welding condition are as follows: weldingvoltage 20-30V, welding current 200-300A, speed of welding 20-30m/h； With wire cutting machine tool from interception surfacing layer metal, deposited metal surface is polished；Test uses ball-mill damage machine.

Wear test process: it is dried up after the sample completely taken with acetone rinsing with hair dryer, on electronic analytical balance Its weight is weighed, weight Mo before abrasion is measured；Then after carrying out wear test, acetone rinsing sample is equally used, and dry up, again Measure weight Mo after sample is worn；Calculate wear weight loss 0.0058g；All positon built-up welding slag can hold molten iron；Self-shield Effect: welding bead pore-free, self-shield excellent effect.

Embodiment five

A kind of preparation method of flux-cored wire:

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Divide and performance requirement determines；Drug core component are as follows: fluoride 30-45%, marble 8-10%, magnesite powder 2-3%, ferrochrome 30-40%, manganese Iron 5-8%, ferrosilicon 4-6%, graphite 5-6%, vanadium iron 2-5%, iron powder are surplus；

Wear test process: it is dried up after the sample completely taken with acetone rinsing with hair dryer, on electronic analytical balance Its weight is weighed, weight Mo before abrasion is measured；Then after carrying out wear test, acetone rinsing sample is equally used, and dry up, again Measure weight Mo after sample is worn；Calculate wear weight loss 0.0056g；All positon built-up welding slag can hold molten iron；Self-shield Effect: welding bead pore-free, self-shield excellent effect.

Embodiment six

A kind of preparation method of flux-cored wire:

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality；Primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder, according to deposited metal at Divide and performance requirement determines；Drug core component are as follows: fluoride 40-45%, marble 9-10%, magnesite powder 2-8%, ferrochrome 35-40%, manganese Iron 5-7%, ferrosilicon 4-6%, graphite 5-6%, vanadium iron 2-4%, iron powder are surplus.

(3) as needed, can U-shaped grain in medicinal powder among along steel band length direction lay a diameter be 0.8mm, with The isometric steel wire of the steel band, steel wire are located at the geometric center of steel band longitudinal cross-section after molding；

By the technical effect of above embodiments it can be found that the present invention is molten by the CaO increase that marble decomposes generation Basicity of slag can improve the physical property of slag, be conducive to stand to holding molten iron when built-up welding and MgO increases viscosity coefficient of dross and solidifying Solid temperature degree realizes welding wire all-position welding, and marble and fluoride slag making, gas-forming agent protect molten drop and molten bath to invade from air Evil, graphite add carbon deoxidation gas making protection；And large-diameter flux-cored wire is solved using the measure for pressing from both sides steel wire in flux-cored wire Welding current welding wire Latitudinal section is uneven, welding technological properties is poor, can not normal weld the technical issues of, keep flux-cored wire straight Diameter can achieve 8mm or more, improve cladding speed；The wearability of matrix is improved using alloying element chromium, manganese, vanadium metal simultaneously.

The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.

Claims

1. a kind of large-diameter self-protection flux-cored welding wire for overlaying welding, including core wire and medicine core, which is characterized in that core wire ingredient is by weight Percentages: C≤0.2%, Mn≤0.3-0.8%, Si≤0.03, Cr≤4-8%, Ni≤0.5%, Cu≤0.4%, S≤0.005%, P ≤ 0.006%, surplus Fe；Drug core component is based on its weight percent: fluoride 30-50%, marble 8-20%, magnesite powder 2- 10%, ferrochrome 30-50%, manganese iron 4-9%, ferrosilicon 4-8%, graphite 4-7%, vanadium iron 2-5%, iron powder are surplus.

2. flux-cored wire according to claim 1, it is characterised in that: drug core component are as follows: fluoride 40-50%, marble 10-20%, magnesite powder 7-10%, ferrochrome 30-50%, manganese iron 4-9%, ferrosilicon 4-8%, graphite 5-7%, vanadium iron 2-5%, iron powder are surplus.

3. flux-cored wire according to claim 1, it is characterised in that: fluoride be one of barium fluoride, lithium fluoride or Two kinds of combinations.

4. a kind of preparation method of large-diameter self-protection flux-cored welding wire for overlaying welding as described in claims 1 to 3: (1) selecting wall Thickness is 0.4mm, and width is the commercially available H08A steel band of 35mm, and being rolled into cross section along steel band length direction is U-shaped；

(2) alloying pellet is added in Xiang Shangshu U-shaped grain, filling rate is 40% ~ 60%, and filling rate is medicinal powder quality and medicinal powder, steel band With the ratio of the sum of wire quality, primary raw material of the alloying pellet as large-diameter flux-cored wire medicinal powder；

(3) diameter is laid along steel band length direction among the medicinal powder in U-shaped grain be 0.8mm and the steel isometric with the steel band Silk, steel wire are located at the geometric center of steel band longitudinal cross-section after molding；