CN115213543A - Water spraying type friction stir welding and postweld heat treatment process combination method - Google Patents
Water spraying type friction stir welding and postweld heat treatment process combination method Download PDFInfo
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- CN115213543A CN115213543A CN202210659801.3A CN202210659801A CN115213543A CN 115213543 A CN115213543 A CN 115213543A CN 202210659801 A CN202210659801 A CN 202210659801A CN 115213543 A CN115213543 A CN 115213543A
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- heat treatment
- stir welding
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- 238000003466 welding Methods 0.000 title claims abstract description 109
- 238000003756 stirring Methods 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 44
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 40
- 238000010438 heat treatment Methods 0.000 title claims abstract description 31
- 238000005507 spraying Methods 0.000 title claims abstract description 13
- 230000032683 aging Effects 0.000 claims abstract description 32
- 238000004140 cleaning Methods 0.000 claims abstract description 5
- 238000005498 polishing Methods 0.000 claims abstract description 5
- 239000007921 spray Substances 0.000 claims description 13
- 229910000838 Al alloy Inorganic materials 0.000 claims description 12
- 238000004321 preservation Methods 0.000 claims description 2
- 238000003825 pressing Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 abstract description 6
- 239000013078 crystal Substances 0.000 abstract description 4
- 238000013461 design Methods 0.000 abstract description 3
- 238000001816 cooling Methods 0.000 description 17
- 239000012071 phase Substances 0.000 description 12
- 239000006104 solid solution Substances 0.000 description 8
- 238000001556 precipitation Methods 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 238000009826 distribution Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/12—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding
- B23K20/122—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding
- B23K20/1245—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding using a non-consumable tool, e.g. friction stir welding characterised by the apparatus
- B23K20/1255—Tools therefor, e.g. characterised by the shape of the probe
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/26—Auxiliary equipment
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
Abstract
The invention relates to a water spraying type friction stir welding and postweld heat treatment process combined method, which comprises the following steps: firstly, polishing and cleaning a workpiece to be welded; secondly, spot welding and clamping the polished and cleaned workpiece to be welded; step three, performing friction stir welding on the workpiece to be welded clamped by spot welding under the condition of water spraying; and step four, performing natural aging on the workpiece subjected to friction stir welding, and then performing artificial aging. The invention does not need to specially design a large water tank and can be used for welding large products. The spot welding clamping is adopted, the clamping process is greatly simplified, the problem that the material is softened and deformed in the second half of the welding line and the distance is increased is solved, and the welding quality is good. The method adopts natural aging after welding and then carries out artificial aging, has loose interval time, and avoids solution treatment with higher cost and more joint plasticity loss. After natural aging and artificial aging treatment, the crystal grains in the weld nucleus area are refined, the precipitated phase is fine, and the joint strength is improved.
Description
Technical Field
The invention belongs to the technical field of friction welding, and particularly relates to a water spraying type friction stir welding and postweld heat treatment process combined method.
Background
The 7 xxx series aluminum alloy belongs to precipitation hardening type aluminum alloy, has higher specific strength and good forming performance, and is widely applied to the fields of aerospace, automobiles and rail transit. Friction Stir Welding (FSW) is a high-quality, efficient and environmentally friendly solid phase joining technique, and can effectively avoid the defects of blowholes, thermal cracks and the like generated in the welding process, so that FSW is widely applied to aluminum alloy welding. Because the phenomena of precipitation phase dissolution or coarsening are easy to occur in the friction stir welding process of the 7 xxx series aluminum alloy, the joint is softened, the welding coefficient is between 60 and 90 percent, and the further improvement of the welding coefficient becomes a concern in the field.
At present, the strengthening process of a 7 XXXX series aluminum alloy friction stir welding joint generally adopts underwater friction stir welding or combined solid solution, aging and other heat treatment methods. When the traditional underwater friction stir welding is carried out, a large water tank needs to be designed, and the traditional underwater friction stir welding is not suitable for welding large products. In addition, the welding and clamping process is complicated, the problem that the material is softened and deformed and the distance is increased easily occurs in the rear half of a welding seam, and the welding quality is seriously influenced. Finally, the traditional post-weld heat treatment needs to be performed with solid solution or aging treatment in time after the welding is completed, the cost of the solid solution treatment is high, and the joint plastic loss is high.
Therefore, it is necessary to provide a special friction stir welding and postweld heat treatment process for large workpieces.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention aims to: the combined method of the water spraying type friction stir welding and the postweld heat treatment process is provided, the clamping process is simplified, the welding of large products can be performed, the problem that the distance is increased due to softening and deformation of materials in the second half of a welding seam is solved, the high-cost solid solution treatment and the high joint plasticity loss are avoided, and the welding quality is good.
The purpose of the invention is realized by the following technical scheme:
a combined method of water spray type friction stir welding and postweld heat treatment processes comprises the following steps:
firstly, polishing and cleaning a workpiece to be welded;
secondly, performing spot welding and clamping on the to-be-welded workpiece which is polished and cleaned;
step three, performing friction stir welding on the workpiece to be welded clamped by spot welding under the condition of water spraying;
and step four, performing natural aging on the workpiece subjected to friction stir welding, and then performing artificial aging.
Further, the material of the workpiece is 7 series aluminum alloy.
Further, in the first step, the welding surface and the areas on two sides of the welding surface of the workpiece to be welded are polished and cleaned.
Furthermore, in the second step, the spot welding fixing parameters are consistent with the formal welding parameters, and the welding length is 10-20 mm.
Furthermore, in the third step, the welding parameters are that the pressing amount is 0.2mm, the rotating speed is 900-1500 rpm, and the welding speed is 30-90 mm/min.
Furthermore, in the third step, the flow rate of the spray water is 0.1-0.3L/s, the water acts on the welded seam after the welding is finished, and the distance between the water column and the stirring head is 10-20 mm.
Further, in the fourth step, the natural aging time is 3-7 days, and the condition is room temperature; the artificial aging temperature is 120-150 ℃, and the heat preservation time is 18-36 h.
And further, in the fourth step, during artificial aging, oil bath constant temperature is adopted.
Compared with the prior art, the invention has the following beneficial effects:
by adopting the water spraying type friction stir welding, natural aging and artificial aging modes, the welding heat input is reduced under the condition of low cost, the strength and the plasticity of the joint are obviously improved, and the 7020 aluminum alloy joint with the grade of 450MPa can be obtained. The equipment development difficulty is low, the processing process is convenient and feasible, and the welding device is suitable for welding large-scale workpieces. The clamping is easy in the welding process, and no coarse grain structure is generated.
Drawings
FIG. 1 (a) shows the thermal history of a friction stir welded joint during welding under air cooling in example 1.
FIG. 1 (b) is a graph showing the heat history of a friction stir welded joint during welding under water-cooling conditions in example 2.
FIG. 2 (a) is a metallographic structure of a nugget region of a friction stir welded joint after heat treatment in air cooling in example 1.
FIG. 2 (b) is a metallographic structure of a nugget region of a friction stir welded joint after heat treatment under water cooling in example 2.
FIGS. 3 (a) - (c) are graphs showing the distribution of the precipitated phases in the nugget area after the heat treatment of the friction stir welded joint in air cooling in example 1.
FIGS. 3 (d) - (f) are graphs showing the distribution of the precipitated phases in the nugget area after heat treatment of the friction stir welded joint under water cooling conditions in example 2.
FIG. 4 shows the tensile properties of friction stir welded joints after heat treatment in different cooling regimes.
FIG. 5 is a flow chart of a water spray type friction stir welding and postweld heat treatment process
Detailed Description
The heat input of the joint can be reduced through the forced cooling effect of flowing water or water spraying and the like, so that the growth of crystal grains and the coarsening of a precipitation phase in the welding process are inhibited. The 7 xxx series aluminum alloy is taken as a heat-treatable strengthened aluminum alloy, and the type, distribution, size and the like of a joint precipitated phase can be regulated and controlled by a postweld heat treatment method, so that the performance of the joint is improved. The dissolving process of the precipitation phase in the welding process is equivalent to solid solution treatment, and after the welding is finished, the precipitation strengthening phase is separated out and grows from the supersaturated solid solution. Natural Aging (NA) is to naturally release internal stress of a workpiece to eliminate or reduce residual stress when the workpiece is placed outdoors or the like. Artificial Aging (AA) can re-precipitate fine precipitated phases in the joint, and is an effective method for improving the joint performance.
The present invention is described in further detail below.
Example 1
Selecting 7020 rolled and annealed aluminum alloy plates with the thickness of 5mm, wherein the chemical compositions of the aluminum alloy plates are shown in the following table:
and under the conventional air cooling condition, polishing and cleaning the workpiece to be welded, and carrying out spot welding clamping at the rotating speed of 1100rpm and the welding speed of 50 mm/min. And (3) carrying out friction stir welding under the conventional air cooling condition, naturally aging the welded product after the welding is finished, and then carrying out artificial aging (120 ℃ for 24 h).
The tensile strength of the welded air-cooled joint is 375.5MPa, the elongation is 6.2%, and the welding coefficient is 80.7%. The tensile strength of the joint after heat treatment was 390.3MPa, the elongation was 5.7%, and the welding coefficient was 83.9%.
Example 2
And a spray pipe is arranged on the friction stir welding equipment, and the water pipe and the stirring head are relatively fixed. And polishing and cleaning a workpiece to be welded, and performing spot welding and clamping by using the rotating speed of 1100rpm and the welding speed of 50 mm/min. And (3) carrying out friction stir welding under the condition of water spraying cooling, naturally aging the welded product after the welding is finished, and then carrying out artificial aging (120 ℃ for 24 h).
After natural aging and artificial aging treatment, the crystal grains in a weld nucleus area are refined, a precipitation phase is smaller than that of a traditional air-cooled joint, and the joint strength is improved.
Compared with the traditional underwater friction stir welding which needs to design a large water tank and is difficult to adapt to the welding of large products, the invention adopts the water spraying type friction stir welding, achieves the effect of forced cooling of water flow, does not need to specially design the large water tank, and can be used for welding large products.
Compared with the traditional complicated welding clamping, the spot welding clamping method has the advantages that the spot welding clamping is adopted, the clamping process is greatly simplified, the problem that the material is softened and deformed in the second half of the welding line to cause the distance to be enlarged is solved, and the welding quality is good.
Compared with the traditional method that the heat treatment after the underwater friction stir welding needs to be carried out in a solid solution or aging treatment in time after the welding is finished, the method adopts natural aging after the welding and then carries out artificial aging, has loose interval time, and avoids the solid solution treatment with higher cost and more joint plasticity loss.
FIG. 1 (a) shows the heat history at the time of welding a friction stir welded joint under air-cooled conditions in example 1.
FIG. 1 (b) shows the thermal history of the friction stir welded joint during welding under water-cooling conditions in example 2.
FIG. 2 (a) is a metallographic structure of a nugget region of a friction stir welded joint after heat treatment in air cooling in example 1.
FIG. 2 (b) is a metallographic structure of a nugget region of a friction stir welded joint after heat treatment under water cooling in example 2.
FIGS. 3 (a) - (c) are graphs showing the distribution of the precipitated phases in the nugget area after the heat treatment of the friction stir welded joint in air cooling in example 1.
FIGS. 3 (d) - (f) are graphs showing the distribution of the precipitated phases in the nugget area after heat treatment of the friction stir welded joint under water cooling conditions in example 2.
As shown in FIGS. 2 and 3, the crystal grains in the nugget area are finer and the precipitation phase is finer and denser after the heat treatment of the water-cooled friction stir welding joint.
FIG. 4 shows that the tensile strength of the water-cooled joint welded by water spray type friction stir welding is 418.5MPa, the elongation is 5.0%, and the welding coefficient is 90.0%. The tensile strength of the joint subjected to artificial aging after welding is 453.0MPa, the elongation is 4.4%, and the welding coefficient is 97.4%. The welding coefficient is a ratio of the tensile strength of the joint to the tensile strength (465.2 MPa) of the 7020 aluminum plate base material.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (8)
1. A water spraying type friction stir welding and postweld heat treatment process combination method is characterized in that: the method comprises the following steps:
firstly, polishing and cleaning a workpiece to be welded;
secondly, spot welding and clamping the polished and cleaned workpiece to be welded;
step three, performing friction stir welding on the workpiece to be welded clamped by spot welding under the condition of water spraying;
and step four, performing natural aging on the workpiece subjected to friction stir welding, and then performing artificial aging.
2. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: the workpiece is made of a 7-series aluminum alloy.
3. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: in the first step, the welding surface and the areas on two sides of the welding surface of the workpiece to be welded are polished and cleaned.
4. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: in the second step, the spot welding fixing parameters are consistent with the formal welding parameters, and the welding length is 10-20 mm.
5. The combined process of water spray friction stir welding and post weld heat treatment according to claim 1, wherein: in the third step, the welding parameters are that the pressing amount is 0.2mm, the rotating speed is 900-1500 rpm, and the welding speed is 30-90 mm/min.
6. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: in the third step, the flow of the spray water is 0.1-0.3L/s, the water acts on the welded seam after the welding is finished, and the distance between the water column and the stirring head is 10-20 mm.
7. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: in the fourth step, the natural aging time is 3 to 7 days, and the condition is room temperature; the artificial aging temperature is 120-150 ℃, and the heat preservation time is 18-36 h.
8. The combined process of water spray friction stir welding and post weld heat treatment as defined in claim 1, wherein: and in the fourth step, during artificial aging, oil bath constant temperature is adopted.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210659801.3A CN115213543A (en) | 2022-06-13 | 2022-06-13 | Water spraying type friction stir welding and postweld heat treatment process combination method |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102528268A (en) * | 2010-12-17 | 2012-07-04 | 中国科学院金属研究所 | Friction stir welding process for enhancing mechanical property of joint |
| CN102658420A (en) * | 2012-04-28 | 2012-09-12 | 沈阳航空航天大学 | Friction stir welding process method for ensuring small deformation and high mechanical properties in the assistance of cold control environment |
| CN104762573A (en) * | 2015-03-28 | 2015-07-08 | 中南大学 | Method for improving quality and mechanical property of 7XXX aluminum alloy stirring friction welded joint |
| CN106181017A (en) * | 2016-07-11 | 2016-12-07 | 中国船舶重工集团公司第七二五研究所 | A kind of friction stir welding method of corronil |
| CN107738066A (en) * | 2017-10-20 | 2018-02-27 | 广西南南铝加工有限公司 | A kind of agitating friction welds aluminium alloy element preparation technology |
| CN108581175A (en) * | 2018-04-24 | 2018-09-28 | 辽宁忠旺铝合金精深加工有限公司 | A kind of aluminum alloy stirring friction welding method with melting welding tack weld |
| US20190084027A1 (en) * | 2017-09-19 | 2019-03-21 | Universitaet Stuttgart | METHOD FOR THE PRODUCTION OF TAILOR WELDED BLANKS (TWBs) |
| RU2686494C1 (en) * | 2018-10-12 | 2019-04-29 | Закрытое акционерное общество "Чебоксарское предприятие "Сеспель" | Method of friction welding with mixing of joints of aluminium alloys |
| CN113263279A (en) * | 2021-05-08 | 2021-08-17 | 北京科技大学 | Method for improving performance of heat-treatable strengthened aluminum alloy friction stir welding joint |
| CN113369667A (en) * | 2021-05-17 | 2021-09-10 | 南京理工大学 | Welding joint of heterogeneous high-strength aluminum alloy and preparation method thereof |
| CN215145646U (en) * | 2021-01-23 | 2021-12-14 | 哈工万联智能装备(苏州)有限公司 | Welding tool with posture induction direction controllable welding-following cooling system |
-
2022
- 2022-06-13 CN CN202210659801.3A patent/CN115213543A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102528268A (en) * | 2010-12-17 | 2012-07-04 | 中国科学院金属研究所 | Friction stir welding process for enhancing mechanical property of joint |
| CN102658420A (en) * | 2012-04-28 | 2012-09-12 | 沈阳航空航天大学 | Friction stir welding process method for ensuring small deformation and high mechanical properties in the assistance of cold control environment |
| CN104762573A (en) * | 2015-03-28 | 2015-07-08 | 中南大学 | Method for improving quality and mechanical property of 7XXX aluminum alloy stirring friction welded joint |
| CN106181017A (en) * | 2016-07-11 | 2016-12-07 | 中国船舶重工集团公司第七二五研究所 | A kind of friction stir welding method of corronil |
| US20190084027A1 (en) * | 2017-09-19 | 2019-03-21 | Universitaet Stuttgart | METHOD FOR THE PRODUCTION OF TAILOR WELDED BLANKS (TWBs) |
| CN107738066A (en) * | 2017-10-20 | 2018-02-27 | 广西南南铝加工有限公司 | A kind of agitating friction welds aluminium alloy element preparation technology |
| CN108581175A (en) * | 2018-04-24 | 2018-09-28 | 辽宁忠旺铝合金精深加工有限公司 | A kind of aluminum alloy stirring friction welding method with melting welding tack weld |
| RU2686494C1 (en) * | 2018-10-12 | 2019-04-29 | Закрытое акционерное общество "Чебоксарское предприятие "Сеспель" | Method of friction welding with mixing of joints of aluminium alloys |
| CN215145646U (en) * | 2021-01-23 | 2021-12-14 | 哈工万联智能装备(苏州)有限公司 | Welding tool with posture induction direction controllable welding-following cooling system |
| CN113263279A (en) * | 2021-05-08 | 2021-08-17 | 北京科技大学 | Method for improving performance of heat-treatable strengthened aluminum alloy friction stir welding joint |
| CN113369667A (en) * | 2021-05-17 | 2021-09-10 | 南京理工大学 | Welding joint of heterogeneous high-strength aluminum alloy and preparation method thereof |
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Application publication date: 20221021 |