A handheld laser welding process protection method for repairing defects

Abstract

The application discloses a kind of handheld laser welding repair defect process protection methods, comprising the following steps: S1: measurement;Part is placed on platform, and the structure state around defect position is clear, defect is in plane, circular surface (inner / outer), corner, corner and so on Position, and the size of defect position is measured, and according to the size of different defect position, it is divided into point defect and surface defect;S2: prepare adaptive repair protection sample plate;According to the size obtained by measuring different defects, prepare repair protection sample plate;S3: assembly;Repair protection sample plate is fixed in defect to be repaired position using fixing piece etc.;S4: defect repair;The way of welding while feeding wire is used to repair defect, to ensure that repair height is higher than surrounding matrix;S5: machining;Remove excess filler metal, and the filling position meets the size requirement of drawing;S6: appearance inspection;Further improve repair quality and repair efficiency.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy laser welding technology, and specifically to a protective method for the process of repairing defects using handheld laser welding. Background Technology

[0002] Aluminum alloy products are indispensable lightweight structural materials in modern high-end manufacturing, widely used in aerospace, automotive, rail transportation, and electronic communications. With the increasing demands for lightweight products, aluminum alloys, with their superior specific strength and specific stiffness, have become an ideal alternative to traditional steel.

[0003] However, during the machining and forming of raw material blanks or castings, defects in dimensions and appearance may occur in localized areas due to the nature of the material, machining methods, or abnormal machining processes leading to overcutting, failing to meet design requirements. Laser welding is commonly used to repair these issues. There are two specific methods for laser welding: one is a handheld laser with manual wire feeding, which effectively repairs porosity and small localized defects; the other is a handheld laser with automatic wire feeding, which effectively repairs localized defects, such as sharp edges and small area defects. However, since defect repair is often performed on a finished product with no machining allowance in the repair area, the following problems arise in actual operation: the contact point of the manual wire feeding cannot completely coincide with the focal point of the handheld laser; the laser's effect on the defect location may increase the defect area; and the laser spot may cause laser ablation pits or scratches on the intact area near the defect.

[0004] During handheld laser automatic wire feeding welding repair, the arc initiation and termination points of the weld are unstable due to the manual wire feed speed, resulting in fusion boundaries. Spatter or defects generated during the repair process are addressed through surface grinding or secondary repair to achieve dimensional and aesthetic compliance. According to welding repair technical requirements, the same location is generally only allowed to be repaired no more than twice. However, repeated repair processes can cause color differences to accumulate on the repaired area surface. Furthermore, if the repaired area is under pressure or stress, it can reduce the structural load-bearing capacity, becoming a weak point for structural failure.

[0005] However, insufficient quality stability and appearance protection throughout the defect repair process lead to product quality and appearance failing to meet design requirements, ultimately resulting in incomplete or inadequate defect repair and product scrapping. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a protective method for the handheld laser welding defect repair process.

[0007] The present invention is achieved through the following technical solutions.

[0008] The technical solution of the present invention: a protective method for handheld laser welding defect repair process, comprising the following steps: S1: Measurement; Place the part on the platform, clarify the surrounding structure of the defect location, the location of the defect, whether it is in a plane, arc surface (inner / outer), corner, edge, etc., and measure the size of the defect location. According to the different sizes of the defect location, it is divided into point defects and surface defects. S2: Prepare a suitable repair and protection template; prepare a repair and protection template according to the dimensions obtained by measuring different defects, and measure the fit at the actual repair location to ensure uniform fit and no abnormal protrusions. S3: Assembly; Use fasteners to fix the repair and protection template to the defect location to be repaired, ensuring that the defect is fully exposed; S4: Defect Repair; Defect repair is carried out by welding and wire feeding simultaneously, ensuring that the repair height is higher than the surrounding substrate; S5: Machining; remove excess filler metal, ensuring the filler location meets the dimensions required in the drawing; S6: Visual inspection; inspect the quality of the repaired surface, which must be free of defects such as pores, cracks, incomplete filling, and failure to polish the complete outer surface.

[0009] Preferably, in step S2, the material of the repair and protection template is the same as that of the product to be repaired.

[0010] Preferably, in step S2, the thickness of the repair and protection template is 1.5-4 mm.

[0011] Preferably, in step S2, the repair and protection template for protecting against point defects has a circular opening working area, and the point defect is located at the center of the circular opening working area.

[0012] Preferably, the circular opening working area of ​​the repair and protection template is a 45-degree angled slope.

[0013] Preferably, in step S2, the repair and protection template for protecting against planar defects is provided with a rectangular opening working area, and the planar defect is located at the center of the rectangular opening working area.

[0014] Preferably, the rectangular opening working area of ​​the repair and protection template is a sloping surface with an angle of 45-60 degrees.

[0015] Preferably, in step S4, for point defects, a handheld laser is used in combination with manual wire feeding, and the maximum overflow size of the repair area is no more than 250%-300% of the maximum size of the defect.

[0016] Preferably, in step S4, for planar defects, a handheld laser welding automatic wire feeding method is used for repair. During the multi-pass welding process, the welding torch angle is at an angle of 45°-60° to the welding direction and at an angle of 15°-30° to the side to be filled. The repair area is determined according to the maximum size of the defect, i.e., its length and width. The repair shape is rectangular, and the welding direction is consistent with the length direction, i.e., the repair welding is carried out in the direction of the maximum weld length.

[0017] Preferably, the arc initiation and termination positions of the welding are both located on the repair and protection template, and the working area size of the repair and protection template is no more than 150% of the maximum size of the defect.

[0018] The beneficial effects of this invention are as follows: 1. By preparing different forms of defect repair protection templates, the defect repair process not only protects the product but also improves welding quality and avoids defects at the arc initiation and termination positions of the weld. Simultaneously, it solves the problems of low boundary fusion between laser welding defect repair and the surrounding defect location, and defects accompanying the welding revision process. This improves the first-pass yield rate of defect repair, reduces the accumulation of color differences caused by multiple laser repairs, and further improves repair quality and efficiency. 2. The use of a repair protection template improves the fault tolerance of the handheld laser welding repair process and simplifies the difficulty of defect repair. On the other hand, compared with conventional repair, the protection template not only protects the appearance quality, but also transfers the defects that originally served as the arc initiation and arc termination positions of the weld from the product surface to the template surface, further improving the weld quality. 3. The repair method of this invention solves the problems of large wound surface, large deformation, and damage to product appearance quality caused by spatter during welding when repairing defects on edges and arc surfaces. It can meet the needs of different structures, locations, and types of defects in aluminum alloy products, and further reduces the difficulty of defect repair. Attached Figure Description

[0019] Figure 1 This is a top view schematic diagram of the repair and protection template fitting with the plane in this invention; Figure 2 This is a side view of the structure of the repair and protection template fitting with the plane in this invention; Figure 3 This is a side view of the structure of the repair and protection template fitting with the arc surface in this invention; Figure 4 This is a top view schematic diagram of the repair and protection template fitting with the arc surface in this invention; Figure 5 This is a schematic diagram of the structure in which the repair and protection template fits the edges in this invention; Figure 6 This is a cross-sectional view of the repair and protection template fitting the edges and corners in this invention.

[0020] Reference numerals in the attached drawings: 1-First repair and protection template; 2-Plane; 3-Point defect; 4-Beveled surface of the first corner; 5-Arc surface; 6-Second repair and protection template; 7-First planar defect; 8-Beveled surface of the second corner; 9-Edge; 10-Second planar defect; 11-Third repair and protection template. 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0023] In this embodiment, a protective method for handheld laser welding defect repair includes the following steps: S1: Measurement; Place the part on the platform, clarify the structural state around the defect location, the location of the defect, whether it is in a plane, arc surface (inner / outer), corner, edge, etc., and measure the size of the defect location. According to the different sizes of the defect location, it is divided into point defects and surface defects.

[0024] S2: Prepare a suitable repair and protection template; prepare a repair and protection template based on the dimensions obtained from measuring different defects, and measure the fit at the actual repair location to ensure uniform fit and no abnormal protrusions.

[0025] The repair and protection template is made of the same material as the product to be repaired, and its thickness is 1.5-4mm. This allows the template to better fit the product and assists in the repair process. This improves the error tolerance of the handheld laser welding repair process and simplifies the difficulty of defect repair.

[0026] S3: Assembly: The fasteners are C-clamps or cable ties. The repair protection template is fixed to the defect to be repaired using C-clamps or cable ties to ensure that the defect is fully exposed.

[0027] S4: Defect Repair: Defect repair is carried out using two methods: handheld laser welding and manual wire feeding or handheld laser welding with automatic wire feeding, ensuring that the repair height is higher than the surrounding substrate.

[0028] The repair and protection template for protecting against point defects has a circular opening working area. The point defect is located at the center of the circular opening working area. The circular opening working area of ​​the repair and protection template is a 45-degree angled surface. This angled surface does not participate in the filling and repair of the defect, but it plays a role in preventing unexpected arcing and splashing.

[0029] The repair protection template for protecting against planar defects has a rectangular opening working area. The planar defect is located at the center of the rectangular opening working area. The rectangular opening working area of ​​the repair protection template is a 45-60 degree angled surface. This angled surface does not participate in the filling and repair of the defect, but it plays a role in preventing unexpected arcing and splashing.

[0030] For point defects, a combination of handheld laser and manual wire feeding is used to ensure that the maximum overflow size of the repair area does not exceed 250%-300% of the maximum defect size, guaranteeing full coverage of the repair area.

[0031] For planar defects, a handheld laser welding automatic wire feeding method is used for repair. During the multi-pass welding process, the welding torch angle is 45°-60° with the welding direction and 15°-30° with the side to be filled. The repair area is determined according to the maximum size of the defect, i.e., length and width. The repair shape is rectangular, and the welding direction is consistent with the length direction, i.e., the repair welding is carried out in the direction of the maximum weld length to ensure full coverage of the repair area and avoid uneven welding.

[0032] The arc initiation and termination points of the welding are both located on the repair and protection template, and the working area of ​​the repair and protection template is no larger than 150% of the maximum defect size. This not only protects the appearance quality, but also eliminates defects generated at the arc initiation and termination points during welding, while preventing spatter during welding and further improving weld quality.

[0033] S5: Machining: Remove excess filler metal by lathe, milling machine or grinding, and ensure that the filler position meets the dimensional requirements of the drawing.

[0034] S6: Visual inspection: The quality of the repaired surface shall be inspected by visual inspection, fluorescence inspection and other methods. There shall be no defects such as pores, cracks, incomplete filling and failure to polish the complete shape surface.

[0035] In this embodiment, repair and protection templates of different shapes are used to fix the defect to be repaired at the location of the defect, depending on the location of the defect. (1) Regarding the point defect 3 in plane 2, refer to Figure 1 and Figure 2The first repair and protection template 1 is disc-shaped, and a circular opening working area is provided in the middle of the first repair and protection template 1. The circular opening working area of ​​the first repair and protection template 1 is a 45-degree inclined plane 4, and the point defect 3 is located in the center of the circular opening working area.

[0036] (2) Regarding the first planar defect 7 on the arc surface 5, refer to Figure 3 and Figure 4 The second repair and protection template 6 is rectangular in shape. The second repair and protection template 6 has a rectangular opening working area. The rectangular opening working area of ​​the second repair and protection template 6 is a sloping surface 8 with an angle of 45-60 degrees. The first surface defect 7 is located at the center of the rectangular opening working area.

[0037] (3) Regarding the second planar defect 10 at the corner 9, refer to Figure 5 and Figure 6 The third repair and protection template 11 is a foldable rectangular plate. The third repair and protection template 11 has a rectangular opening working area, and the second planar defect 10 is located in the rectangular opening working area.

[0038] The working principle of this invention is as follows: By preparing defect repair protection templates of different forms, point defects and planar defects are repaired by welding, realizing the protection of the product during the defect repair process, while improving welding quality and avoiding defects at the arc initiation and termination positions of the weld. It also solves the problems of poor boundary fusion between the laser welding defect repair and the surrounding defect location, and defects accompanying the welding revision process, improving the first-pass yield of defect repair, reducing the accumulation of color differences caused by multiple laser repairs, and further improving repair quality and efficiency. The repair method of this invention solves the problems of large wound areas, large deformation, and damage to the appearance quality of products caused by spatter during welding when repairing defects on edges and arc surfaces. It further reduces the difficulty of defect repair for different structures, locations, and types of defects in aluminum alloy products.

[0039] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the description and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A protective method for handheld laser welding defect repair process, characterized in that, Includes the following steps: S1: Measurement; Place the part on the platform, clarify the surrounding structure of the defect location, the location of the defect, whether it is in a plane, arc surface (inner / outer), corner, edge, etc., and measure the size of the defect location. According to the different sizes of the defect location, it is divided into point defects and surface defects. S2: Prepare a suitable repair and protection template; prepare a repair and protection template according to the dimensions obtained by measuring different defects, and measure the fit at the actual repair location to ensure uniform fit and no abnormal protrusions. S3: Assembly; Use fasteners to fix the repair and protection template to the defect location to be repaired, ensuring that the defect is fully exposed; S4: Defect Repair; Defect repair is carried out by welding and wire feeding simultaneously, ensuring that the repair height is higher than the surrounding substrate; S5: Machining; remove excess filler metal, ensuring the filler location meets the dimensions required in the drawing; S6: Visual inspection; inspect the quality of the repaired surface, which must be free of defects such as pores, cracks, incomplete filling, and failure to polish the complete outer surface.

2. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In step S2, the material of the repair and protection template is the same as that of the product to be repaired.

3. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In S2, the thickness of the repair and protection template is 1.5-4mm.

4. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In S2, the repair and protection template for protecting against point defects has a circular opening working area, and the point defect is located at the center of the circular opening working area.

5. The method for protecting the handheld laser welding defect repair process according to claim 4, characterized in that: The circular opening working area of ​​the repair and protection template has a 45-degree bevel at the edge.

6. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In step S2, the repair and protection template for protecting against planar defects is provided with a rectangular opening working area, and the planar defect is located at the center of the rectangular opening working area.

7. The method for protecting the handheld laser welding defect repair process according to claim 6, characterized in that: The rectangular opening working area of ​​the repair and protection template is a sloping surface with an angle of 45-60 degrees.

8. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In S4, for point defects, a handheld laser is used in combination with manual wire feeding, and the maximum overflow size of the repair area is no more than 250%-300% of the maximum size of the defect.

9. The method for protecting the handheld laser welding defect repair process according to claim 1, characterized in that: In step S4, for planar defects, a handheld laser welding automatic wire feeding method is used for repair. During the multi-pass welding process, the welding torch angle is 45°-60° to the welding direction and 15°-30° to the side to be filled. The repair area is determined according to the maximum size of the defect, i.e., the length and width. The repair shape is rectangular, and the welding direction is consistent with the length direction, i.e., the repair welding is carried out in the direction of the maximum weld length.

10. The method for protecting the handheld laser welding defect repair process according to claim 9, characterized in that: The arc initiation and termination positions of the welding are both located on the repair and protection template, and the working area of ​​the repair and protection template is no larger than 150% of the maximum size of the defect.

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