CN107617817A - A kind of welding method of light-alloy slab - Google Patents
A kind of welding method of light-alloy slab Download PDFInfo
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- CN107617817A CN107617817A CN201711051672.5A CN201711051672A CN107617817A CN 107617817 A CN107617817 A CN 107617817A CN 201711051672 A CN201711051672 A CN 201711051672A CN 107617817 A CN107617817 A CN 107617817A
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Abstract
The present invention provides a kind of welding method of light-alloy slab, is had the following advantages that compared with existing light-alloy slab friction stir welding method：In a first aspect, can promote in stir friction welding process, light-alloy slab internal heat is more uniform, abundant, so as to realize high-quality, the efficient welding of light-alloy slab；Second aspect, the present invention need not increase the processes such as weld preheating, post weld heat treatment, simplify technological process, save weld interval, improve operating efficiency；The third aspect, the present invention commonly use common welding tooling just, it is not required that purchase resistance material, reduce cost without carrying out special improvement to welding tooling.
Description
Technical field
The present invention relates to light-alloy welding field, more particularly to a kind of welding method of light-alloy slab.
Background technology
Density is less than 3.5g/cm3Aluminium alloy, magnesium alloy be our usually said light-alloys.It is fast in lightweight process
During speed promotes, light-alloy has huge market application potential.Welding be in light-alloy commercial applications pass through frequently with
A kind of connected mode.
Agitating friction welding is a kind of method of the light-alloy Solid-phase welding such as magnesium, aluminium.In stir friction welding process, make
With the position to be welded of stirring-head insertion workpiece, by the agitating friction between stirring-head and workpiece, frictional heat makes the position metal
From its front end posteriorly Plastic Flow in hot plastic state and under the pressure effect of stirring-head, so that part to be welded is welded as
One entirety.Agitating friction welding has the following advantages that：（1）Welding point heat affected area microscopic structure changes small residual stress
Than relatively low, welding workpiece is unlikely to deform；（2）The welding joints height of longer weld seam, heavy in section, diverse location can once be completed：
（3）Mechanization, automation are conveniently realized in operating process, and equipment is simple, and energy consumption is low, and effect is high, require low to operating environment：（4）
Welding wire need not be added, is not required to weld preceding oxide film dissolving when welding aluminium alloy, it is not necessary to which protective gas, cost are low；（5）Solderable fire check is quick
The material of sense, it is adapted to welding dissimilar materials：（6）Welding process is safe and pollution-free, smoke dust, radiationless etc..
But for single welding thickness 10mm ~ 35mm light-alloy slab agitating friction weldering, welding parameter compared with
Want narrow more for thin plate., can be by because stir friction welding process is actually a very numerous and diverse transient
To the interference of several factors, quality of weld joint is directly influenced.Agitating friction weldering is substantially a metal in friction-stir
The lower heating softening of effect, occurs superplasticity flowing, this just needs metal to be sufficiently heated, and rheological resistance is smaller；And stirring
It is that upper relative superiority or inferiority is low, wide at the top and narrow at the bottom the characteristics of weld seam rheology area temperature field, i.e., in throat depth direction thermometer in friction welding process
Now low for the high bottom in top, it is narrow that high-temperature region shows as the wide bottom in top；Increase along throat depth, rheology area sharp temperature drop.
So for light-alloy slab, if the method using similar plate sheet welding, it tends to be difficult to which the welding for obtaining high quality connects
Head.
In order to improve the agitating friction of light-alloy slab welding effect, patent（Publication number CN101885109）Propose one
AZ31 Magnesium Alloy in Friction Stir welding methods thick 10~20mm of kind, the mixing needle is round platform spiral shape；Actually should
It is similar with below thickness 10mm Magnesium Alloy in Friction Stir welding method to invent the welding method provided, and round platform is spiral stirs
Thermo parameters method of the magnesium alloy thick plate in stir friction welding process can not be improved well by mixing pin.Patent（Publication number
CN102689090）One kind 4 ~ 50mm thickness magnesium, Aluminum Alloy Plate friction stir welding method are proposed, is mainly characterized by before welding
Weld seam back, which applies, acts only on weld seam back stirring-head advance side and the controlled thermal source heated to the side；This not only increases
The manufacturing process and expense of frock, and add energy resource consumption and resistance material expense.Patent（Publication number
CN101885109）The thick aluminum alloy plate preheating friction stir welding method of a kind of weld preheating, post weld heat treatment is proposed, should
The problem of increase energy consumption and complex procedures similarly be present in method.
The content of the invention
The deficiencies in the prior art in view of the above, it is an object of the invention to provide a kind of welding side of light-alloy slab
Method, promote rheology area temperature slowly to decline along throat depth direction, obtain the light-alloy slab friction stir welding of high quality,
Simplify tool structure and processing step simultaneously, realize high-quality, the high-efficiency stirring friction welding of light-alloy slab.
In order to achieve the above objects and other related objects, the present invention provides a kind of welding method of light-alloy slab, and it is special
Sign is：Light-alloy slab mother metal to be welded is rigidly fixed on backing plate first；Then it is to be welded stirring-head to be rotating insertion
In mother metal, after stirring-head stops 3 ~ 15s when reaching default position, speed change is carried out using different rotary speeies and speed of welding
Formula agitating friction welds, the welding of described speed changing type agitating friction refer to before weld seam 1/3rd length using 1500 ~
Relatively higher 3000r/min rotary speed, 100 ~ 30mm/min relatively slower gait of march, is used in residue length
Relatively lower 300 ~ 1400r/min rotary speed, the relatively faster gait of march of 110 ~ 600mm/min, welding process axis
Shoulder volume under pressure keeps constant；After stirring-head reaches weld seam end, continue to extract stirring-head after being rotating 3 ~ 15s of stop, complete
Light-alloy thick plates.
As preferred：Before welding, electricity consumption is drilled in weld seam initiating terminal and drilled, and the 8 ~ 30mm of diameter phi in hole, the depth 6 in hole ~
20mm.Drilled in weld seam initiating terminal, be advantageous to the agitating friction welding starting stage obtain more uniformly, more fully sweating heat
Amount, an effective warm is provided for follow-up welding, so as to promote magnesium alloy thick plate to be obtained in stir friction welding process
More uniform, sufficient heat is obtained, so as to obtain the magnesium alloy thick plate welding point of high quality.
As preferred：The stirring-head is made up of retained part, shoulder and mixing needle part, by T10 steel,
3Cr2W8V steel, 4Cr5MoSiV steel, 4Cr5MoSiV1 steel, GH4169 high temperature alloys or W-25Ce alloys are made；The axle
Shoulder lower surface is provided with multiple grooves, 18 ~ 40mm of shaft shoulder diameter phi；The mixing needle is cone and is provided with outer peripheral face more
Group screw thread and three planes, to increase in welding process weld metal in the mobility of thickness direction, mixing needle outside diameter φ
10 ~ 25mm, 6 ~ 18mm of mixing needle end diameter φ, 9.6 ~ 34.2mm of mixing needle length.
/ 3rd length of the present invention before weld seam using the relatively higher rotary speeies of 1500 ~ 3000r/min,
Gait of march relatively slower 100 ~ 30mm/min, it is in order to which magnesium alloy thick plate obtains more effectively in stir friction welding process
Preheating, evenly, more fully heat, so as to solve, magnesium alloy thick plate welding parameter is narrow, quality of weld joint is poor
Problem.
As preferred：0.2 ~ 0.6mm of the shaft shoulder volume under pressure.
Light-alloy of the present invention refers to aluminium alloy and magnesium alloy.
As described above, the beneficial effects of the invention are as follows：Compared with existing light-alloy slab friction stir welding method, first
Aspect, it can be promoted using the welding of speed changing type agitating friction in stir friction welding process, light-alloy slab internal heat is more
Uniformly, fully, so as to realizing high-quality, the efficient welding of light-alloy slab；Second aspect, the present invention need not increase weld preheating,
The processes such as post weld heat treatment, technological process is simplified, save weld interval, improve operating efficiency；The third aspect, the present invention need not
Special improvement is carried out to welding tooling, commonly uses common welding tooling just, it is not required that purchase resistance material, reduce into
This.
Brief description of the drawings
Fig. 1 is the 10mm thickness AZ31 Magnesium Alloy in Friction Stir welding line outside drawings of the method welding of embodiment 1 in the present invention；
Fig. 2 is the 35mm thickness AZ31 Magnesium Alloy in Friction Stir welding line outside drawings of the method welding of embodiment 2 in the present invention；
Fig. 3 is the thick 6061 aluminum alloy stirring friction welding weld appearance figures of 10mm of the method welding of embodiment 3 in the present invention；
Fig. 4 is the thick 6061 aluminum alloy stirring friction welding weld appearance figures of 35mm of the method welding of embodiment 4 in the present invention.
Embodiment
Illustrate the embodiment of invention by particular specific embodiment below, those skilled in the art can be by this specification
Disclosed content understands other advantages and effect of invention easily.
Embodiment 1：Rolling state AZ31 magnesium alloy thick plate mother metals to be welded are rigidly fixed on backing plate first, mother metal size
For 300mm × 100mm × 10mm（Length × width × height）；Then electricity consumption is drilled in the drilling of weld seam initiating terminal, the diameter phi 8mm in hole, hole
Depth 6mm；Then stirring-head is rotating in insertion magnesium alloy thick plate to be welded, stirring-head is made by 4Cr5MoSiV steel,
Shaft shoulder diameter 18mm, mixing needle length 9.6mm, mixing needle outside diameter 10mm, mixing needle end diameter 6mm, stirring-head reach
After stopping 3s during default position, speed changing type agitating friction welding is carried out using different rotary speeies and speed of welding, specifically
Refer to that 1/3rd length are using rotary speed relatively higher 3000r/min, 100mm/min relatively slower row before weld seam
Enter speed, traveling is fast faster relatively using rotary speed relatively lower 1400r/min, 600mm/min in residue length
Spend, shaft shoulder volume under pressure keeps 0.2mm constant in welding process；After stirring-head reaches weld seam end, continue after being rotating stop 3s
Stirring-head is extracted, completes the welding of 10mm thickness AZ31 magnesium alloy thick plates.Weld appearance, as described in Figure 1.Face of weld is bright, into
Type is good, through inside X ray nondestructive inspection weld seam without cavity, tunnel the defects of, drawn experiment after find weld seam tensile strength reach
To the 96% of mother metal, welding quality is high.
Embodiment 2：Rolling state AZ31 magnesium alloy thick plate mother metals to be welded are rigidly fixed on backing plate first, mother metal size
For 300mm × 100mm × 35mm（Length × width × height）；Then electricity consumption is drilled in the drilling of weld seam initiating terminal, the diameter phi 30mm in hole, hole
Depth 20mm；Then stirring-head is rotating in insertion magnesium alloy thick plate to be welded, stirring-head made by 4Cr5MoSiV steel and
Into, shaft shoulder diameter 40mm, mixing needle length 34.2mm, mixing needle outside diameter 25mm, mixing needle end diameter 18mm, stirring-head
After stopping 15s when reaching default position, speed changing type agitating friction welding is carried out using different rotary speeies and speed of welding,
It is relatively slower using rotary speed relatively higher 1500r/min, 30mm/min to specifically refer to 1/3rd length before weld seam
Gait of march, advanced faster relatively using the relatively lower rotary speeies of 800r/min, 110mm/min in residue length
Speed, shaft shoulder volume under pressure keeps 0.6mm constant in welding process；After stirring-head reaches weld seam end, continue to be rotating stop 15s
Stirring-head is extracted afterwards, completes the welding of 35mm thickness AZ31 magnesium alloy thick plates.Weld appearance, as described in Figure 2.Face of weld light,
Forming, through inside X ray nondestructive inspection weld seam without cavity, tunnel the defects of, drawn experiment after find weld seam tensile strength
Reach the 82% of mother metal, welding quality is high.
Embodiment 3：6061-T6 aluminium alloy thick plate mother metals to be welded are rigidly fixed on backing plate first, mother metal size is
300mm×100mm×10mm（Length × width × height）；Then electricity consumption is drilled in the drilling of weld seam initiating terminal, the diameter phi 8mm in hole, hole
Depth 6mm；Then stirring-head is rotating in insertion mother metal to be welded, stirring-head is made by 4Cr5MoSiV steel, shaft shoulder diameter
18mm, mixing needle length 9.6mm, mixing needle outside diameter 10mm, mixing needle end diameter 6mm, stirring-head reach default position
After stopping 3s when putting, the welding of speed changing type agitating friction is carried out using different rotary speeies and speed of welding, in particular to welded
/ 3rd length use the relatively slower gait of march of the relatively higher rotary speeies of 2500r/min, 80mm/min before seam,
Using rotary speed relatively lower 1200r/min, the relatively faster gait of march of 300mm/min in residue length, welded
Shaft shoulder volume under pressure keeps 0.2mm constant in journey；After stirring-head reaches weld seam end, continue to pull out stirring-head after being rotating stop 3s
Go out, complete the welding of 10mm thickness 6061-T6 aluminium alloy thick plates.Weld appearance, as described in Figure 3.Face of weld is bright, forming；Through X
Ray nondestructive inspection, weld seam inside zero defect；Find that weld seam tensile strength reaches the 85% of mother metal after drawn experiment.
Embodiment 4：6061-T6 aluminium alloy thick plate mother metals to be welded are rigidly fixed on backing plate first, mother metal size is
300mm×100mm×35mm（Length × width × height）；Then electricity consumption is drilled in the drilling of weld seam initiating terminal, the diameter phi 30mm in hole, hole
Depth 20mm；Then stirring-head is rotating in insertion mother metal to be welded, stirring-head is made by 4Cr5MoSiV steel, the shaft shoulder is straight
Footpath 40mm, mixing needle length 34.2mm, mixing needle outside diameter 25mm, mixing needle end diameter 18mm, stirring-head reach default
Position when stop 15s after, using different rotary speeies and speed of welding carry out the welding of speed changing type agitating friction, in particular to
/ 3rd length are using rotary speed relatively higher 2000r/min, 60mm/min relatively slower traveling speed before weld seam
Degree, using rotary speed relatively lower 300r/min, the relatively faster gait of march of 120mm/min, weldering in residue length
Shaft shoulder volume under pressure keeps 0.6mm constant in termination process；After stirring-head reaches weld seam end, continue to stir after being rotating stop 15s
Head extraction is mixed, completes the welding of 35mm thickness 6061-T6 aluminium alloy thick plates.Weld appearance, as described in Figure 4.Face of weld is bright, shaping
It is good；Through X ray nondestructive inspection, weld seam inside zero defect；Find that weld seam tensile strength reaches the 74% of mother metal after drawn experiment.
Any person skilled in the art can all repair under the spirit and scope without prejudice to invention to above-described embodiment
Decorations change.Therefore, such as those of ordinary skill in the art without departing from invention disclosed spirit and technology
All equivalent modifications completed under thought or change, it should be covered by the claim invented.
Claims (5)
- A kind of 1. welding method of light-alloy slab, it is characterised in that：Light-alloy slab mother metal to be welded is rigidly fixed first On backing plate；Then stirring-head is rotating in insertion mother metal to be welded, after stirring-head stops 3 ~ 15s when reaching default position, Speed changing type agitating friction welding is carried out using different rotary speeies and speed of welding, shaft shoulder volume under pressure is kept not in welding process Become；After stirring-head reaches weld seam end, continue to extract stirring-head after being rotating 3 ~ 15s of stop, complete light-alloy thick plates.
- A kind of 2. welding method of light-alloy slab according to claim 1, it is characterised in that：Described speed changing type stirring Friction welding refer to before weld seam 1/3rd length using rotary speed relatively higher 1500 ~ 3000r/min, 100 ~ Gait of march relatively slower 30mm/min, in residue length using the relatively lower rotary speeies of 300 ~ 1400r/min, The relatively faster gait of march of 110 ~ 600mm/min.
- A kind of 3. welding method of light-alloy slab according to claim 1, it is characterised in that：Before welding, electric drill is used Drilled in weld seam initiating terminal, the 8 ~ 30mm of diameter phi in hole, the 6 ~ 20mm of depth in hole.
- A kind of 4. welding method of light-alloy slab according to claim 1, it is characterised in that：The stirring-head is by clamping Partly, shoulder and mixing needle part composition, stirring-head is by T10 steel, 3Cr2W8V steel, 4Cr5MoSiV steel, 4Cr5MoSiV1 Steel, GH4169 high temperature alloys or W-25Ce alloys are made；The shaft shoulder lower surface is provided with multiple grooves, shaft shoulder diameter phi 18 ~40mm；The mixing needle is cone and multigroup screw thread and three planes are provided with outer peripheral face, to increase in welding process Weld metal 10 ~ 25mm of mixing needle outside diameter φ, 6 ~ 18mm of mixing needle end diameter φ, is stirred in the mobility of thickness direction Mix 9.6 ~ 34.2mm of pin length.
- A kind of 5. welding method of light-alloy slab according to claim 1, it is characterised in that：The shaft shoulder volume under pressure is excellent Elect 0.2 ~ 0.6mm as.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711051672.5A CN107617817A (en) | 2017-11-01 | 2017-11-01 | A kind of welding method of light-alloy slab |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711051672.5A CN107617817A (en) | 2017-11-01 | 2017-11-01 | A kind of welding method of light-alloy slab |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108296606A (en) * | 2018-02-08 | 2018-07-20 | 天津工业大学 | A kind of narrow gap P-GMAW arc sensing welding seam tracking methods |
| CN110919161A (en) * | 2019-11-29 | 2020-03-27 | 湖南九方焊接技术有限公司 | Minor diameter shaft shoulder stirring head |
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| US6729526B2 (en) * | 2001-09-12 | 2004-05-04 | Hitachi, Ltd. | Friction stir welding apparatus and method and processing apparatus and method |
| CN1593834A (en) * | 2003-09-11 | 2005-03-16 | 波音公司 | Apparatus and method for friction stir welding with a variable speed pin |
| CN101885109A (en) * | 2010-07-30 | 2010-11-17 | 北京理工大学 | Friction stir welding method of medium plate AZ AZ1 magnesium alloy |
| CN102076455A (en) * | 2008-06-30 | 2011-05-25 | 爱尔康何纳吕公司 | Pulsed friction stir welding method using at least two alternated mode, each having forward velocity with obviously different mean value |
| CN102601517A (en) * | 2012-04-06 | 2012-07-25 | 江苏科技大学 | Same-direction different-speed double-shoulder stir friction welding device and application method |
| CN103286435A (en) * | 2013-06-20 | 2013-09-11 | 山东大学 | Stir head for friction stir machining and fabrication of metal matrix composite |
| CN103658965A (en) * | 2012-08-30 | 2014-03-26 | 苹果公司 | Dynamic adjustment of friction stir welding process parameters based on weld temperature |
| CN104227226A (en) * | 2014-09-30 | 2014-12-24 | 湖北三江航天红阳机电有限公司 | Method for conducting preheating and friction stir welding on thick plate aluminum alloy |
| CN105522275A (en) * | 2016-02-05 | 2016-04-27 | 河南正航主轴科技有限公司 | Stirring head for friction stir welding |
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- 2017-11-01 CN CN201711051672.5A patent/CN107617817A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6729526B2 (en) * | 2001-09-12 | 2004-05-04 | Hitachi, Ltd. | Friction stir welding apparatus and method and processing apparatus and method |
| CN1593834A (en) * | 2003-09-11 | 2005-03-16 | 波音公司 | Apparatus and method for friction stir welding with a variable speed pin |
| CN102076455A (en) * | 2008-06-30 | 2011-05-25 | 爱尔康何纳吕公司 | Pulsed friction stir welding method using at least two alternated mode, each having forward velocity with obviously different mean value |
| CN101885109A (en) * | 2010-07-30 | 2010-11-17 | 北京理工大学 | Friction stir welding method of medium plate AZ AZ1 magnesium alloy |
| CN102601517A (en) * | 2012-04-06 | 2012-07-25 | 江苏科技大学 | Same-direction different-speed double-shoulder stir friction welding device and application method |
| CN103658965A (en) * | 2012-08-30 | 2014-03-26 | 苹果公司 | Dynamic adjustment of friction stir welding process parameters based on weld temperature |
| CN103286435A (en) * | 2013-06-20 | 2013-09-11 | 山东大学 | Stir head for friction stir machining and fabrication of metal matrix composite |
| CN104227226A (en) * | 2014-09-30 | 2014-12-24 | 湖北三江航天红阳机电有限公司 | Method for conducting preheating and friction stir welding on thick plate aluminum alloy |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108296606A (en) * | 2018-02-08 | 2018-07-20 | 天津工业大学 | A kind of narrow gap P-GMAW arc sensing welding seam tracking methods |
| CN110919161A (en) * | 2019-11-29 | 2020-03-27 | 湖南九方焊接技术有限公司 | Minor diameter shaft shoulder stirring head |
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