CN114043068A - Method for controlling flash forming of linear friction welding joint - Google Patents
Method for controlling flash forming of linear friction welding joint Download PDFInfo
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- CN114043068A CN114043068A CN202111232729.8A CN202111232729A CN114043068A CN 114043068 A CN114043068 A CN 114043068A CN 202111232729 A CN202111232729 A CN 202111232729A CN 114043068 A CN114043068 A CN 114043068A
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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
- B23K20/123—Controlling or monitoring the welding process
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Abstract
The invention relates to a method for controlling flash forming of a linear friction welding joint, which comprises the following steps: pressing the ends of two workpieces to be welded together and providing relative vibration between the two workpieces to cause the two workpieces to rub against each other to provide friction welding; wherein, the two workpieces are respectively sleeved with a check ring, and the check rings are arranged at the end parts which are close to the two workpieces and are contacted with each other. Based on the condition that welding burrs are easy to diverge in the current friction welding process, the end part close to the mutual contact of the two workpieces is provided with the retaining ring, and the retaining ring is used for extruding and limiting the extrusion of the burrs before the welding is finished, so that the formation of the defect of non-welding joint caused by the separation of the roots of the burrs is avoided, the forming quality of the burrs of the linear friction welding joint is effectively improved, and the friction welding effect is further improved.
Description
Technical Field
The invention relates to the technical field of linear friction welding, in particular to a method for controlling flash forming of a linear friction welding head.
Background
The welding process principle of linear friction welding is that one workpiece vibrates in a reciprocating mode at high frequency, and the other workpiece is in contact with the vibrating workpiece under the action of certain friction pressure and generates mutual friction to generate friction heat, and finally a connecting joint is formed. Normally, the extruded flashes are connected together as shown in fig. 1, but when the equipment capacity is not enough to weld some large-area workpieces or the welded flashes formed by the two workpieces are branched due to the physical property parameter characteristics of some special materials, as shown in fig. 2, unwelded defects are easy to occur at the roots of the separated flashes and extend into the workpieces, and the connection reliability of the workpieces is affected.
At present, the generation and the extension of flash are in a free state in the linear friction welding process and are not controlled. When the capacity of the equipment is insufficient or the physical performance parameter characteristics of some special materials cause the welding flash to crack, and the unwelded defect can occur at the root.
In view of the above, it is desirable to provide a linear friction welding forming control method for preventing the burrs from branching off and avoiding the root defects of the burrs, so as to improve the quality of the linear friction welding forming.
Disclosure of Invention
(1) Technical problem to be solved
The embodiment of the invention provides a method for controlling the formation of flashes of a linear friction welding joint. The method has the advantages of simple steps, convenience and quickness in operation and remarkable effect, and can remarkably improve the forming effect of the friction welding flash.
(2) Technical scheme
The embodiment of the invention provides a method for controlling the formation of flash of a linear friction welding joint, which comprises the following steps: pressing the ends of two workpieces to be welded together and providing relative vibration between the two workpieces to cause the two workpieces to rub against each other to provide friction welding; wherein, the two workpieces are respectively sleeved with a check ring, and the check rings are arranged at the end parts which are close to the two workpieces and are contacted with each other.
Furthermore, the end parts of the two workpieces are extruded together to form a welding line after friction welding, and the distance between the outer peripheral wall of the retainer ring and the surface of the workpiece is at least 3 mm.
Further, the distance from the end part of the retainer ring, which is extruded together by the two workpieces, in the initial installation state is not less than the shortened distance of the welded workpieces.
Furthermore, the shortening amount of any workpiece after friction welding is smaller than the distance between the check ring and the end face of the workpiece.
Further, the vibration is caused by a vibration device acting on at least one of the two workpieces.
Further, the workpiece and the check ring are made of different materials.
Further, the check rings are connected to the corresponding workpieces.
Further, the check ring is connected to the welding fixture of the corresponding workpiece.
(3) Advantageous effects
Based on the condition that welding burrs are easy to diverge in the current linear friction welding process, the end part close to the mutual contact of the two workpieces is provided with the retaining ring, and the retaining ring is used for extruding and limiting the extrusion of the burrs before the welding is finished, so that the formation of the defect of non-welding joint caused by the separation of the roots of the burrs is avoided, the forming quality of the burrs of the linear friction welding head is effectively improved, and the linear friction welding effect is further improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic view of a typical linear friction welding process.
FIG. 2 is a schematic illustration of a typical linear friction weld causing weld flash to diverge.
FIG. 3 is a perspective view of a linear friction welded joint in accordance with an embodiment of the present invention.
FIG. 4 is a side view of a linear friction welded joint in accordance with an embodiment of the present invention.
FIG. 5 is a schematic front view of a linear friction welded joint configuration in an initial welding state in accordance with an embodiment of the present invention.
FIG. 6 is a schematic front view of a linear friction welded connection structure after welding is completed according to an embodiment of the present invention
In the figure: the device comprises a first workpiece 1, a second workpiece 2, a first check ring 3 and a second check ring 4.
Detailed Description
The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the invention and are not intended to limit the scope of the invention, i.e., the invention is not limited to the embodiments described, but covers any modifications, alterations, and improvements in the parts, components, and connections without departing from the spirit of the invention.
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
The present application will be described in detail with reference to fig. 3 to 6 in conjunction with an embodiment.
The invention provides a method for controlling flash forming of a linear friction welding joint, which comprises the following steps: pressing the ends of two workpieces to be welded together and providing relative vibration between the two workpieces to cause the two workpieces to rub against each other to provide friction welding; wherein, the two workpieces are respectively sleeved with a check ring, and the check rings are arranged at the end parts which are close to the two workpieces and are contacted with each other.
An embodiment of the present invention will be described below with reference to fig. 3, and referring to fig. 3, in the embodiment of the present invention, two workpieces, that is, a first workpiece 1 and a second workpiece 2, are provided to be welded together, a right end of the first workpiece 1 and a left end of the second workpiece 2 are pressed together, and relative vibration is provided between the first workpiece 1 and the second workpiece 2 to rub the two workpieces against each other to provide friction welding (specifically, the first workpiece 1 may be provided with relative vibration using a dedicated friction welding apparatus, or the second workpiece 2 may be provided with relative vibration, or the first workpiece 1 and the second workpiece 2 may be provided with relative vibration, respectively, the dedicated friction welding apparatus in fig. 3 is not shown). In the embodiment of the present invention, a first retainer ring 3 is disposed on a first workpiece 1, a second retainer ring 4 is disposed on a second workpiece 2, and the first retainer ring 3 and the second retainer ring 4 are respectively disposed at the end portions where the first workpiece 1 and the second workpiece 2 contact each other (i.e., the middle portion in fig. 3).
Thus, when the special friction welding equipment applies relative vibration to one of the workpieces to enable the first workpiece 1 and the second workpiece 2 to rub against each other to perform a friction welding process, the contact part of the first workpiece 1 and the second workpiece 2 generates softening deformation due to high-frequency friction contact heat, a connecting joint is formed, and the connecting joint after softening deformation extrudes fins. According to the embodiment of the invention, the first check ring 3 is arranged on the first workpiece 1, the second check ring 4 is arranged on the second workpiece 2, the extruded flash is always kept near the connecting joint under the limitation of the first check ring 3 and the second check ring 4, and is quickly fused together in a molten state without bifurcation. Therefore, the arrangement of the first retainer ring 3 and the second retainer ring 4 can extrude and limit movement of the flash before welding is finished, so that the formation of non-welding defects caused by separation of the root parts of the flash is avoided.
In summary, in the embodiment of the invention, based on the situation that the welding flash is likely to crack in the current friction welding process, the check ring is arranged at the end part close to the two workpieces which are contacted with each other, and the check ring is used for squeezing and limiting the movement of the flash before the welding is finished, so that the formation of the non-welded defect caused by the separation of the root of the flash is avoided, the flash forming quality of the friction welding head is effectively improved, and the friction welding effect is further improved.
Further in accordance with another embodiment of the invention, the ends of the workpieces are pressed together to form a weld by friction welding, and the outer peripheral wall of the retainer ring is at least 3mm from the surface of the workpieces. In the following, an embodiment of the present invention will be described with reference to fig. 3 and 4, in which fig. 4 is a right side view of fig. 3, and in fig. 3 and 4, a weld is formed after friction welding at a position where the first workpiece 1 and the second workpiece 2 are pressed against each other, the peripheral wall of the first retainer ring 3 should be at least 3mm away from the surface of the first workpiece 1, and the peripheral wall of the second retainer ring 4 should be at least 3mm away from the surface of the second workpiece 2. That is to say, when the tip of first work piece 1, second work piece 2 overstocks together, forms bellied overlap, the peripheral wall of the retaining ring of first work piece 1, second work piece 2 is protruding 3mm height at least to can play the extrusion to the overlap better and restrict the effect that the overlap removed, thereby avoid the overlap root to break away from and cause the formation of not seam defect.
Specifically, referring to fig. 4, the distances from the outer peripheral wall of the second retainer 4 to the surface of the second workpiece 2 are S1 and S2, respectively, where the minimum value of S1 and S2 should be greater than 3mm, so that the second retainer 4 can be ensured to press and restrict the movement of the flash on that side. Specifically, the outer peripheral wall of the retainer ring is at least 3mm long from the surface of the workpiece. The embodiment of the present invention is described with reference to fig. 3 and 4, and the minimum value of the distances S1 and S2 from the outer peripheral wall of the second retainer 4 to the surface of the second workpiece 2 in fig. 4 of the embodiment of the present invention is at least 3mm higher, so that the second retainer 4 can be ensured to press and limit the movement of the flash on the side. Further, the minimum distance between the outer peripheral wall of the first retainer ring 3 and the surface of the first workpiece 1 should be at least 3mm higher than the surface of the first workpiece 1, so that the first retainer ring 3 and the second retainer ring 4 can well play roles of extruding the flash and limiting the movement of the flash from two sides.
Of course, the distance from the peripheral wall of the retainer ring to the workpiece surface is at least 3mm, and the distance can be 3mm or 4mm during actual linear friction welding, and the distance can be determined according to actual conditions, and should not constitute a limitation to the present application.
Further in accordance with another embodiment of the present invention, the retainer ring is spaced from the end of the two workpieces pressed together in the initial installed condition by a distance not less than the shortened length of the workpieces after friction welding. An embodiment of the present invention is described below with reference to fig. 5 and 6, in fig. 5 of the embodiment of the present invention, a distance between the first retainer ring 3 and the end of the first workpiece 1 and the end of the second workpiece 2, which are pressed together, in an initial installation state is L, a distance between the second retainer ring 4 and the end of the first workpiece 1 and the end of the second workpiece 2, which are pressed together, in the initial installation state is also L (of course, different distances are also possible, in this embodiment, for convenience of description, the distances between the first retainer ring 3 and the second retainer ring 4 and the end of the first workpiece 1 and the end of the second workpiece 2, which are pressed together, are unified as L, which does not affect a specific protection range), distances between the two retainer rings after friction welding and the weld center are shown in fig. 6, distances between the retainer ring 3 and the second retainer ring 4 and the weld center are respectively w, in the embodiment of the present invention, because the end of the first workpiece 1 and the second workpiece 2 after friction, will be softened at a high temperature and then shortened by a certain length, therefore, the distance between the end part of the check ring extruded together with the two workpieces in the initial installation state is not less than the width of the welding seam after friction welding, certain shortening allowance of the workpieces can be reserved, normal formation of the welding seam for forming the flash is ensured, the check ring does not obstruct the formation of the welding seam, and the check ring can well play roles in extruding and limiting the movement of the flash.
Further in accordance with another embodiment of the invention, the amount of shortening of either workpiece after friction welding should be less than the distance of its upper retainer ring from the end face of that side workpiece. An embodiment of the present invention will be described with reference to the above embodiment and fig. 5 and 6, in which the shortening amount of any one of the workpieces after friction welding is less than L-w. Therefore, referring to fig. 5 and fig. 6, that is, the shortening of the workpieces after friction welding should be less than the distance L from the end of the two workpieces pressed together in the initial installation state, so that after the shortening of the workpieces, the retaining rings on the two sides can well play the roles of pressing the flash and limiting the movement of the flash.
In particular, according to one embodiment of the invention, the vibration is caused by a vibration device acting on at least one of the two workpieces. For example, a dedicated friction welding device may drive the first workpiece to vibrate, a dedicated friction welding device may drive the second workpiece to vibrate, or a dedicated friction welding device may drive the two workpieces to vibrate respectively.
Further, according to another embodiment of the present invention, the workpiece and the retainer ring are made of different materials. The work piece can be guaranteed with the retaining ring different in material of retaining ring that the work piece can not bond together after friction weld melts, and the optimal condition is that the melting point of retaining ring material is higher than the melting point of work piece, can not cause the retaining ring to melt after the work piece melts like this, and then the work piece can not bond together with the retaining ring.
Specifically, according to one embodiment of the present invention, the retainer rings are attached to the corresponding workpieces. Therefore, the check ring can move along with the corresponding workpiece, the position of the check ring relative to the workpiece is ensured not to be changed, and the limit position of the flash is further ensured not to be changed.
Particularly, according to another embodiment of the invention, the check ring is connected to the welding fixture of the corresponding workpiece, so that the check ring can be conveniently fixed, installed and detached.
The invention is illustrated below in another embodiment.
Referring to FIGS. 3-6, high-strength steel workpieces are joined by linear friction welding with a welding cross-sectional area of 1500mm2The method adopts linear friction welding and optimization of technological parameters to form the shape that the flash is always forked and the defect of no welding exists at the root. Before the design of the joint structure, the shortening of the workpiece is determined through a process test.
Firstly, the welding interface is designed into a structure as shown in fig. 3 and 5, wherein the first retainer ring 3 and the second retainer ring 4 are separated from the initial welding interface by a distance L. The shortening amount of the single-side test piece in the welding process should be controlled to be not less than L-w.
And (3) welding is carried out, when the welding process is finished, the distance between the retaining rings on the two sides of the first workpiece 1 and the second workpiece 2 reaches the width w, the retaining rings extrude the flash, and therefore the finally extruded flash is formed under the extrusion action of the retaining rings on the two sides, and the formation of the root cracking and the unwelded defects of the flash is limited.
Based on the condition that welding burrs are easy to crack in the current friction welding process, the end parts, which are close to two workpieces and are contacted with each other, of the two workpieces are provided with the check rings, the burrs are extruded and limited to move by the check rings before welding is finished, the formation of the defect of non-welding due to the separation of the roots of the burrs is avoided, the forming quality of the burrs of the friction welding head is effectively improved, and the friction welding effect is further improved.
It should be clear that the embodiments in this specification are described in a progressive manner, and the same or similar parts in the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. For embodiments of the method, reference is made to the description of the apparatus embodiments in part. The present invention is not limited to the specific steps and structures described above and shown in the drawings. Also, a detailed description of known process techniques is omitted herein for the sake of brevity.
The above description is only an example of the present application and is not limited to the present application. Various modifications and alterations to this application will become apparent to those skilled in the art without departing from the scope of this invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.
Claims (8)
1. A method for controlling the formation of flash of a linear friction welding joint is characterized by comprising the following steps:
pressing the ends of two workpieces to be welded together and providing relative vibration between the two workpieces to cause the two workpieces to rub against each other to provide friction welding;
wherein, the two workpieces are respectively sleeved with a check ring, and the check rings are arranged at the end parts which are close to the two workpieces and are contacted with each other.
2. A method of controlling flash formation of a linear friction weld joint according to claim 1 wherein the ends of the workpieces are pressed together and friction welded to form a weld, the outer peripheral wall of the retainer ring being at least 3mm from the surface of the workpieces.
3. A method of controlling flash forming of a linear friction welding joint as set forth in claim 2, characterized in that said retainer ring is located at a distance from the end portions of the two workpieces pressed together in the initial installation state not less than the shortened distance of the workpieces after welding.
4. A method for controlling flash forming of a linear friction welding joint according to claim 3, characterized in that the amount of shortening of any one of the workpieces after friction welding is smaller than the distance of the retainer ring from the end face of the workpiece.
5. A method for controlling the formation of flash at a linear friction welding joint as set forth in claim 1, characterized in that said vibration is caused by a vibration means acting on at least one of the two workpieces.
6. The method of claim 1, wherein the workpiece and the retainer ring are made of different materials.
7. A method of controlling flash forming of a linear friction welding joint as set forth in claim 1, wherein said check ring is attached to the corresponding work.
8. The method for controlling flash forming of a linear friction welding joint according to claim 1, wherein said check ring is attached to a welding jig of a corresponding work.
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| CN202111232729.8A CN114043068B (en) | 2021-10-22 | 2021-10-22 | Linear friction welding joint flash forming control method |
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| CN202111232729.8A CN114043068B (en) | 2021-10-22 | 2021-10-22 | Linear friction welding joint flash forming control method |
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| CN114043068B CN114043068B (en) | 2023-02-28 |
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| US4850772A (en) * | 1988-04-15 | 1989-07-25 | Trw Inc. | Friction-weldable stud |
| US5154340A (en) * | 1991-07-02 | 1992-10-13 | Peacock Harold B | Method and device for frictional welding |
| US5492581A (en) * | 1993-05-13 | 1996-02-20 | Rolls-Royce Plc | Friction welding |
| CN1451509A (en) * | 2002-04-19 | 2003-10-29 | 富士乌兹克斯株式会社 | Friction welding device |
| CN204094304U (en) * | 2014-09-26 | 2015-01-14 | 山东明珠石油装备制造有限公司 | The U-shaped clipper of friction welding |
| CN105583516A (en) * | 2016-03-18 | 2016-05-18 | 中国汽车工程研究院股份有限公司 | Vibration friction welding process for long glass fiber reinforced thermoplastic intake manifold |
| CN108879278A (en) * | 2018-05-31 | 2018-11-23 | 深圳供电局有限公司 | A method of it reducing overhead transmission line conductor strain insulator pipe and crimps overlap rate |
| CN109175672A (en) * | 2018-11-05 | 2019-01-11 | 中国航空制造技术研究院 | Overlap deformation controller in hole and method during linear friction welding |
| US20190076969A1 (en) * | 2017-09-11 | 2019-03-14 | Hitachi Automotive Systems Americas, Inc. | Friction stir welding flash and burr control |
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2021
- 2021-10-22 CN CN202111232729.8A patent/CN114043068B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4850772A (en) * | 1988-04-15 | 1989-07-25 | Trw Inc. | Friction-weldable stud |
| US5154340A (en) * | 1991-07-02 | 1992-10-13 | Peacock Harold B | Method and device for frictional welding |
| US5492581A (en) * | 1993-05-13 | 1996-02-20 | Rolls-Royce Plc | Friction welding |
| CN1451509A (en) * | 2002-04-19 | 2003-10-29 | 富士乌兹克斯株式会社 | Friction welding device |
| CN204094304U (en) * | 2014-09-26 | 2015-01-14 | 山东明珠石油装备制造有限公司 | The U-shaped clipper of friction welding |
| CN105583516A (en) * | 2016-03-18 | 2016-05-18 | 中国汽车工程研究院股份有限公司 | Vibration friction welding process for long glass fiber reinforced thermoplastic intake manifold |
| US20190076969A1 (en) * | 2017-09-11 | 2019-03-14 | Hitachi Automotive Systems Americas, Inc. | Friction stir welding flash and burr control |
| CN108879278A (en) * | 2018-05-31 | 2018-11-23 | 深圳供电局有限公司 | A method of it reducing overhead transmission line conductor strain insulator pipe and crimps overlap rate |
| CN109175672A (en) * | 2018-11-05 | 2019-01-11 | 中国航空制造技术研究院 | Overlap deformation controller in hole and method during linear friction welding |
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