Stirring tool, filler wire friction stir welding device and welding method

Abstract

The invention discloses a stirring tool, a wire filling friction stir welding device and a welding method.The stirring tool comprises a main shaft, a shaft shoulder and a stirring head, the shaft shoulder is fixed to the lower end of the main shaft and arranged outside the stirring head in a sleeving mode, and the stirring head comprises a clamping handle, a center main stirring needle and a plurality of auxiliary stirring needles; the upper portion of the clamping handle is fixed in the main shaft, a spiral groove is formed in the outer wall of the lower portion of the clamping handle, the center main stirring needle is fixed to the center of the bottom of the clamping handle, the auxiliary stirring needles are fixed to the bottom of the clamping handle and evenly distributed in the circumferential direction of the center main stirring needle, and a wire feeding hole is formed in one side of the lower portion of the shaft shoulder. The wire filling friction stir welding device comprises the wire feeding tool and the stirring tool, the wire feeding tool is used for feeding the wire into the shaft shoulder through the wire feeding hole, dependence on reserved machining allowance of base metal is avoided, the problem of welding seam quality caused by too large gaps is avoided, and the problems that equipment complexity is high and process control difficulty is large are solved.

Description

Technical Field

[0001] This invention relates to the field of welding, and in particular to a stirring tool, a wire-filled friction stir welding apparatus, and a welding method. Background Technology

[0002] Traditional FSW (Fluid Steel Welding) processes rely on the shoulder of the stirring head to apply significant downward pressure to the workpiece surface, generating frictional heat and sealing the ductile metal. During this process, the forging action of the shoulder causes axial (thickness-direction) plastic flow of material in the weld center region, resulting in a theoretical thickness in this area that is lower than the original thickness of the base material. To address this issue, current industrial practice necessitates pre-welding machining allowances, followed by post-weld machining to remove burrs and restore dimensions. This not only increases material costs but also, in thickness-sensitive lightweight aerospace structures, disrupts material continuity and can impair the structure's fatigue performance due to work hardening or stress concentration.

[0003] Because the dimensions of the stirring pin and the shoulder of a traditional stirring head are fixed, it does not have the ability to dynamically adjust according to the gap and adaptively fill defects. Due to the lack of sufficient plastic material to fill the gap, it is very difficult to ensure the ideal assembly accuracy of zero gap and zero misalignment in the welding process of large components, which can easily lead to defects such as incomplete penetration, poor weld formation and weak connection.

[0004] In current friction stir welding technology, a shrinkage cavity, or keyhole, is left at the weld end when the stirring pin is lifted at the welding endpoint. The keyhole is a severe stress concentration source and can easily become the initiation point of fatigue cracks under cyclic loading, posing a direct threat to the safe lifespan of aerospace structures. A retractable stirring head is generally used to solve the keyhole problem. The stirring pin and shoulder are designed separately; as the endpoint approaches, the stirring pin retracts into the shoulder at a certain speed, while the shoulder presses down, causing the plastic metal to flow and fill the keyhole during the pin's withdrawal. However, this method suffers from high equipment complexity and difficulty in process control. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a stirring tool, a wire-filled friction stir welding device and a welding method, which eliminates the reliance on the pre-processing allowance of the base material, avoids weld quality problems caused by excessive gap, and solves the problems of high equipment complexity and difficulty in process control.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a stirring tool, including a main shaft, a shoulder, and a stirring head. The shoulder is fixed to the lower end of the main shaft and sleeved on the outside of the stirring head. The stirring head includes a clamping handle, a central main stirring pin, and multiple auxiliary stirring pins. The upper part of the clamping handle is fixed in the main shaft, and a spiral groove is provided on the outer wall of the lower part of the clamping handle. The central main stirring pin is fixed at the center of the bottom of the clamping handle, and a thread is provided on the outer wall of the central main stirring pin. The multiple auxiliary stirring pins are all fixed to the bottom of the clamping handle and are evenly distributed along the circumference of the central main stirring pin. The central main stirring pin and the multiple auxiliary stirring pins all extend from the bottom of the shoulder to the outside. A wire feeding hole is provided on one side of the lower part of the shoulder for feeding wire.

[0007] Preferably, the wire feeding hole corresponds to the position of the spiral groove.

[0008] Preferably, the pitch of the spiral groove is 9.8mm to 10.8mm, and the groove depth is 2.7mm to 3mm.

[0009] Preferably, a positioning groove is provided on one side of the upper part of the clamping handle.

[0010] Preferably, the positioning groove is a rectangular groove.

[0011] Preferably, the length of the central main stirring pin is greater than the length of the auxiliary stirring pin.

[0012] Preferably, two auxiliary stirring needles are provided.

[0013] The present invention also provides a wire-feed friction stir welding apparatus, including a wire feeding tool and a stirring tool. The wire feeding tool is used to feed wire into the shoulder through the wire feeding hole, and the wire feeding tool is used to move synchronously with the stirring tool along the weld direction.

[0014] Preferably, the wire feeding tool includes a wire feeding mechanism and a wire feeding guide tube fixed to the end of the wire feeding mechanism, wherein the end of the wire feeding guide tube away from the wire feeding mechanism corresponds to the position of the wire feeding hole.

[0015] The present invention also provides a welding method based on a filler wire friction stir welding device, comprising the following steps: Step 1: Butt-assemble two base materials of the same thickness, leaving a gap in the middle. Move the rotating stirring tool to the position directly above the starting point of the weld. While maintaining the preset speed, apply pressure along the axial direction to press down, so that the central main stirring needle and multiple auxiliary stirring needles are gradually inserted into the area to be welded. Step 2: Before the formal welding begins, the wire is continuously and stably fed by the wire feeding tool at a preset wire feeding speed. Under the rotational friction and stirring action of the shaft shoulder, the central main stirring pin and multiple auxiliary stirring pins, the wire heats up and reaches a plastic state. The stirring tool rotates and stays at the joint start position to ensure that the filling material formed after the wire is plasticized fills the initial keyhole formed by the initial pressure. At the same time, the main shaft is lifted upward to compensate for the local thinning of the plate thickness caused by the initial pressure and ensure the weld is flat. Step 3: Subsequently, the stirring tool moves at a constant speed along the weld direction according to the preset welding parameters, and the wire feeding tool moves synchronously with the stirring tool along the weld direction. The wire feeding speed of the wire feeding tool is increased, and the plasticized wire continuously flows into the weld gap area under the forging action of the shoulder. Under the stirring action of the central main stirring needle, it undergoes a full metallurgical reaction with the base material on both sides of the gap. As the filler material is continuously added, a uniform deposition layer is gradually formed on the surface of the base material. Step 4: When the stirring tool reaches the welding endpoint, continue its rotation while raising its height to expand the volume of the plastic zone; at this time, further increase the wire feeding speed of the wire feeding tool and stop at the welding endpoint to ensure that sufficient wire is fully filled into the finishing keyhole; before the main shaft is raised, reduce the rotation speed of the stirring head and apply greater forging pressure to promote the filling material to be fully compacted and metallurgically bonded in a high-pressure environment, thereby achieving complete and dense filling of the finishing keyhole; Step 5: The wire feeding tool stops feeding wire, and the main shaft drives the stirring head to slowly rise, completely filling the end keyhole position.

[0016] The present invention achieves the following technical effects compared to the prior art: The present invention features a wire feeding hole on one side of the lower part of the shoulder. A wire feeding tool is used to feed wire into the shoulder through the wire feeding hole. The wire feeding tool moves synchronously with the stirring tool along the weld direction. During the welding process, the wire is plasticized and fills the weld, solving the problem of weld thickness reduction caused by shoulder compression and material flow deformation. This eliminates the reliance on pre-machining allowances in the base material, ensuring good dimensional accuracy and mechanical properties of the welded structure, and avoiding additional material costs. At the same time, the plasticized wire filling the weld avoids incomplete penetration, poor weld formation, and weak connections caused by excessive weld gaps. These defects reduce assembly precision requirements, solve the problem of high assembly gap requirements for the base materials to be welded, and avoid weld quality problems caused by excessive gaps. Before the spindle is lifted, the stirring head speed is reduced, and greater forging pressure is applied to ensure that the filler material formed by the plasticization of the wire is fully compacted and metallurgically bonded in a high-pressure environment. This achieves complete and dense filling of the tail keyhole, thereby eliminating keyhole defects caused by the retraction of the stirring head at the end of the weld, ensuring the integrity and continuity of the weld, and solving the problems of high equipment complexity and difficult process control caused by the use of a retractable stirring head.

[0017] Furthermore, the stirring head adopts a structure in which a central main stirring pin is combined with multiple auxiliary stirring pins in the circumferential direction. The central main stirring pin ensures the basic stirring friction effect, and at the same time, the central main stirring pin is provided with threads to promote the flow of plasticized material to the weld. The multiple auxiliary stirring pins in the circumferential direction can enhance the stirring effect of the material, improve the material mixing uniformity in the weld area, and the multi-stirring pin design can disperse the stress during the welding process and extend the service life of the stirring head. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the stirring head in the stirring tool provided by the present invention; Figure 2 for Figure 1 A magnified view of a section at point A in the middle; Figure 3 This is a schematic diagram of the structure of the filler wire friction stir welding device provided by the present invention; Figure 4 for Figure 3 A magnified view of a section at point B.

[0020] Explanation of reference numerals in the attached drawings: 1. Stirring head; 101. Clamping handle; 102. Positioning groove; 103. Spiral groove; 104. Central main stirring pin; 105. Auxiliary stirring pin; 106. Thread; 2. Main shaft; 3. Shoulder; 4. Wire feeding mechanism; 5. Wire feeding guide tube; 6. Wire; 7. Base material; 8. Weld; 9. Deposition layer. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The purpose of this invention is to provide a stirring tool, a wire-filled friction stir welding device, and a welding method that eliminates the reliance on pre-reserved machining allowances for the base material, avoids weld quality problems caused by excessive gaps, and solves the problems of high equipment complexity and difficulty in process control.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figures 1-4 As shown, this embodiment provides a stirring tool, including a main shaft 2, a shoulder 3, and a stirring head 1. The shoulder 3 is fixed to the lower end of the main shaft 2 and sleeved on the outside of the stirring head 1. The stirring head 1 includes a clamping handle 101, a central main stirring needle 104, and a plurality of auxiliary stirring needles 105. The upper part of the clamping handle 101 is fixed in the main shaft 2. A spiral groove 103 is provided on the outer wall of the lower part of the clamping handle 101. The central main stirring needle 104 is fixed at the center of the bottom of the clamping handle 101. A thread 106 is provided on the outer wall of the central main stirring needle 104. The plurality of auxiliary stirring needles 105 are all fixed to the bottom of the clamping handle 101 and are evenly distributed along the circumference of the central main stirring needle 104. The central main stirring needle 104 and the plurality of auxiliary stirring needles 105 extend from the bottom of the shoulder 3 to the outside. A wire feeding hole is provided on one side of the lower part of the shoulder 3 for feeding wire 6.

[0025] In this embodiment, the stirring head 1 adopts a structure in which a central main stirring pin 104 and multiple circumferential auxiliary stirring pins 105 cooperate. The central main stirring pin 104 ensures the basic stirring friction effect, and at the same time, the central main stirring pin 104 is provided with threads 106 to promote the flow of plasticized material to the weld seam 8. The multiple circumferential auxiliary stirring pins 105 can enhance the stirring effect of the material and improve the material mixing uniformity in the weld seam area. At the same time, the multi-stirring pin design can disperse the stress during the welding process and extend the service life of the stirring head 1.

[0026] Specifically, the wire feeding hole corresponds to the position of the spiral groove 103. In this embodiment, the wire feeding hole corresponds to the middle position of the spiral groove 103.

[0027] Specifically, the pitch of the spiral groove 103 is 9.8mm~10.8mm, and the groove depth of the spiral groove 103 is 2.7mm~3mm. That is, in this embodiment, a spiral groove 103 with a large pitch and a deep groove is adopted. Compared with the traditional spiral groove, it can drive the welding material to flow along the axial and circumferential directions more efficiently, promote the full fusion of the filler wire and the base material 7, and effectively solve the problem of spreading and fusion of filler wire material, especially in the filler wire welding scenario.

[0028] In this specific embodiment, the pitch of the spiral groove 103 is 10mm, and the groove depth of the spiral groove 103 is 3mm.

[0029] In this embodiment, a positioning groove 102 is provided on one side of the upper part of the clamping handle 101, which is fixed to the spindle 2 by a flat-end set screw. By setting the positioning groove 102 and cooperating with the flat-end set screw, the precise positioning of the stirring head 1 and the spindle 2 is achieved, ensuring the coaxiality and perpendicularity of the stirring head 1 after assembly, ensuring the stability of the stirring action during welding, and avoiding weld defects caused by assembly errors.

[0030] In this specific embodiment, the positioning groove 102 is a rectangular groove.

[0031] Specifically, the length of the central main stirring pin 104 is greater than the length of the auxiliary stirring pin 105. In this embodiment, the outer wall of the area where the central main stirring pin 104 protrudes downward relative to the auxiliary stirring pin 105 is provided with threads 106.

[0032] In this specific embodiment, two auxiliary stirring needles 105 are provided.

[0033] like Figure 3 and Figure 4 As shown, this embodiment also provides a wire-feed friction stir welding device, including a wire feeding tool and a stirring tool. The wire feeding tool is used to feed wire 6 into the shoulder 3 through the wire feeding hole, and the wire feeding tool is used to move synchronously with the stirring tool along the weld direction.

[0034] Specifically, the wire feeding tool includes a wire feeding mechanism 4 and a wire feeding guide tube 5 fixed to the end of the wire feeding mechanism 4. The end of the wire feeding guide tube 5 away from the wire feeding mechanism 4 corresponds to the position of the wire feeding hole.

[0035] In this specific embodiment, the diameter of the wire feeding hole is 2mm. The wire 6 is a 4043 aluminum alloy welding wire with a diameter of 1.6mm, the base material 7 is a 3mm thick 6061 aluminum alloy plate, and the exposed length of the central main stirring needle 104 of the stirring head 1 is 2.8mm.

[0036] In this specific embodiment, the angle between the central axis of the spindle 2 and the normal to the workpiece to be welded during the welding process is 1.5°. The stirring tool is cooled with deionized coolant, and the material of the stirring tool is H13 steel.

[0037] This embodiment also provides a welding method based on a filler wire friction stir welding device, including the following steps: Step 1: Assemble two base materials 7 of the same thickness by butt joint, leaving a gap in the middle. Move the rotating stirring tool directly above the starting position of the weld 8. While maintaining the preset speed, apply pressure along the axial direction to gradually insert the central main stirring needle 104 and multiple auxiliary stirring needles 105 into the area to be welded.

[0038] Specifically, two 3mm thick 6061 aluminum alloy plates are butt-assembled with a 1mm gap between them. The preset rotation speed is 3000 r / min, the forging pressure is controlled at 6kN, and the pressing depth is maintained at 0.2mm.

[0039] Step 2: Before the formal welding begins, wire 6 is continuously and stably fed by a wire feeding tool at a preset feeding speed; specifically, the preset feeding speed is 500 mm / min. Under the rotational friction and stirring action of the shoulder 3, the central main stirring pin 104, and multiple auxiliary stirring pins 105, the wire 6 heats up and reaches a plastic state, forming a small local material pool at the joint start position. The stirring tool remains rotating and stationary at the joint start position. In this embodiment, the stirring tool remains rotating and stationary at the joint start position for 1-2 seconds to ensure that the filler material formed after the wire 6 is plasticized fills the initial keyhole formed by the initial downward pressure, thereby forming a transition substrate rich in filler material at the welding start end. At the same time, the main shaft 2 is raised upward. In this embodiment, the main shaft 2 is raised upward by 0.2 mm to compensate for the local thinning of the plate thickness caused by the initial downward pressure and to ensure the flatness of the weld 8.

[0040] Step 3: Subsequently, the stirring tool moves at a constant speed along the weld direction according to the preset welding parameters, and the wire feeding tool moves synchronously with the stirring tool along the weld direction, with the wire feeding speed of the wire feeding tool increased. In this embodiment, the wire feeding speed is increased to 900 mm / min. The plasticized wire 6 continuously flows into the gap area of ​​the weld 8 under the forging action of the shoulder 3, and under the stirring action of the central main stirring pin 104, it undergoes a full metallurgical reaction with the base material 7 on both sides of the gap, achieving a reliable bond. This process significantly improves the density and continuity of the weld 8, effectively suppresses the generation of incomplete welding and welding cracks, and reduces the stringent requirements on the assembly accuracy of the workpiece. With the continuous addition of filler material, a uniform deposition layer 9 is gradually formed on the surface of the base material 7, which not only eliminates the thickness reduction phenomenon commonly seen in traditional friction stir welding, but also greatly reduces the flash defects caused by excessive material extrusion.

[0041] Specifically, the preset welding parameters include a rotation speed of 3000 r / min and a travel speed of 200 mm / min.

[0042] Step 4: When the stirring tool reaches the welding endpoint, continue its rotation while raising its height. In this embodiment, the height is raised by 0.1mm~0.3mm to expand the volume of the plastic zone and create favorable conditions for filling the finishing keyhole. At this time, the wire feeding speed of the wire feeding tool is further increased and stopped at the welding endpoint to ensure that sufficient wire 6 is fully filled into the finishing keyhole. In this embodiment, the wire feeding speed is further increased to 1500 mm / min and stopped at the welding endpoint for 5s. Before the main shaft 2 is raised, the rotation speed of the stirring head 1 is reduced, and a greater forging pressure is applied. In this embodiment, the rotation speed of the stirring head 1 is reduced to 1800 r / min, and a forging pressure of 8 kN is applied to ensure that the filling material is fully compacted and metallurgically bonded in a high-pressure environment, thereby achieving complete and dense filling of the finishing keyhole.

[0043] Step 5: The wire feeding tool stops feeding wire, and the main shaft 2 drives the stirring head 1 to slowly rise. The tail key hole position is completely filled, forming a metallurgical bonding point with the same strength as the weld body formed by the filling material, so that the entire joint area has uniform performance and a smooth appearance.

[0044] As can be seen, during the welding process, the rotating stirring head 1 penetrates the workpiece joint and moves forward. Under the thermomechanical action generated by the shoulder 3, the central main stirring pin 104, and multiple auxiliary stirring pins 105 in the circumferential direction, the weld metal is plasticized. At the same time, the pre-prepared wire 6 is continuously and precisely fed into the plasticized molten pool in front of the stirring head 1 through the wire feeding guide tube 5. The wire 6 and the base material 7 are fully mixed, diffused, and reshaped under high temperature and high pressure, and finally cool and solidify behind the stirring head 1 to form a dense weld 8 with enhanced properties.

[0045] In this embodiment, a wire feeding hole is provided on one side of the lower part of the shoulder 3. The wire feeding tool is used to feed the wire 6 into the shoulder 3 through the wire feeding hole. The wire feeding tool is used to move synchronously with the stirring tool along the direction of the weld 8. During the welding process, the wire 6 is plasticized and filled into the weld 8, which solves the problem of the thickness reduction of the weld 8 area caused by the downward pressure of the shoulder 3 and the deformation of the material flow. This eliminates the reliance on the pre-reserved machining allowance of the base material 7, ensures good structural dimensional accuracy and mechanical properties after welding, and avoids additional material costs.

[0046] Meanwhile, the plasticized wire 6 filling the weld 8 avoids defects such as incomplete penetration, poor weld formation and weak connection caused by excessive gap in the weld 8, reduces the assembly accuracy requirements, solves the problem of high assembly gap requirements for the base material 7 to be welded, and avoids weld quality problems caused by excessive gap.

[0047] Before the main shaft 2 is lifted, the rotation speed of the stirring head 1 is reduced, and a greater forging pressure is applied to promote the filling material formed by the plasticization of the wire 6 to be fully compacted and metallurgically bonded in a high-pressure environment, thereby achieving complete and dense filling of the end keyhole, thus eliminating the keyhole defect caused by the retraction of the stirring head 1 at the end of the weld 8, ensuring the integrity and continuity of the weld 8, and solving the problems of high equipment complexity and difficulty in process control caused by the use of a retractable stirring head.

[0048] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A stirring tool, characterized in that, The device includes a main shaft, a shoulder, and a stirring head. The shoulder is fixed to the lower end of the main shaft and sleeved on the outside of the stirring head. The stirring head includes a clamping handle, a central main stirring pin, and multiple auxiliary stirring pins. The upper part of the clamping handle is fixed in the main shaft. A spiral groove is provided on the outer wall of the lower part of the clamping handle. The central main stirring pin is fixed at the center of the bottom of the clamping handle. The outer wall of the central main stirring pin is provided with threads. Multiple auxiliary stirring pins are fixed to the bottom of the clamping handle and are evenly distributed around the circumference of the central main stirring pin. The central main stirring pin and multiple auxiliary stirring pins extend from the bottom of the shoulder to the outside. A wire feeding hole is provided on one side of the lower part of the shoulder for feeding wire.

2. The stirring tool of claim 1, wherein The wire feeding hole corresponds to the position of the spiral groove.

3. The stirring tool of claim 1, wherein The pitch of the spiral groove is 9.8mm~10.8mm, and the groove depth is 2.7mm~3mm.

4. The stirring tool of claim 1, wherein A positioning groove is provided on one side of the upper part of the clamping handle.

5. The stirring tool of claim 4, wherein The positioning groove is a rectangular groove.

6. The stirring tool of claim 1, wherein The length of the central main stirring needle is greater than the length of the auxiliary stirring needle.

7. The stirring tool of claim 1, wherein Two auxiliary stirring needles are provided.

8. A wire-feeding friction stir welding device characterized by comprising: It includes a wire feeding tool and a stirring tool as described in any one of claims 1-7, wherein the wire feeding tool is used to feed wire into the shoulder through the wire feeding hole, and the wire feeding tool is used to move synchronously with the stirring tool along the weld direction.

9. The wire fill friction stir welding device of claim 8, wherein, The wire feeding tool includes a wire feeding mechanism and a wire feeding guide tube fixed to the end of the wire feeding mechanism, wherein the end of the wire feeding guide tube away from the wire feeding mechanism corresponds to the position of the wire feeding hole.

10. A welding method based on the wire-feeding friction stir welding device according to any one of claims 8-9, characterized by, Includes the following steps: Step 1: Butt-assemble two base materials of the same thickness, leaving a gap in the middle. Move the rotating stirring tool to the position directly above the starting point of the weld. While maintaining the preset speed, apply pressure along the axial direction to press down, so that the central main stirring needle and multiple auxiliary stirring needles are gradually inserted into the area to be welded. Step 2: Before the formal welding begins, the wire is continuously and stably fed by the wire feeding tool at a preset wire feeding speed. Under the rotational friction and stirring action of the shaft shoulder, the central main stirring pin and multiple auxiliary stirring pins, the wire heats up and reaches a plastic state. The stirring tool rotates and stays at the joint start position to ensure that the filling material formed after the wire is plasticized fills the initial keyhole formed by the initial pressure. At the same time, the main shaft is lifted upward to compensate for the local thinning of the plate thickness caused by the initial pressure and ensure the weld is flat. Step 3: Subsequently, the stirring tool moves at a constant speed along the weld direction according to the preset welding parameters, and the wire feeding tool moves synchronously with the stirring tool along the weld direction. The wire feeding speed of the wire feeding tool is increased, and the plasticized wire continuously flows into the weld gap area under the forging action of the shoulder. Under the stirring action of the central main stirring needle, it undergoes a full metallurgical reaction with the base material on both sides of the gap. As the filler material is continuously added, a uniform deposition layer is gradually formed on the surface of the base material. Step four, when the stirring tool travels to the welding end point, continue to keep its rotating state, while lifting its height to expand the plastic zone volume; at this time, the wire feeding speed of the wire feeding tool is further increased, and it stays at the welding end point, so that sufficient wire material is fully filled into the finishing spoon hole; before the spindle is lifted, the stirring head speed is reduced, while a greater forging pressure is applied, so that the filling material is fully compacted in a high pressure environment and the metallurgical bonding is completed, so as to realize the complete and dense filling of the finishing spoon hole; Step five, the wire feeding tool stops feeding wire, and the spindle drives the stirring head to slowly lift, and the finishing spoon hole position is completely filled flat.

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