Titanium alloy cabin body casting laser cladding repair method

Abstract

The application provides a titanium alloy cabin body casting laser cladding repair method, comprising the following steps: obtaining position information of defects exceeding the standard in a titanium alloy cabin body casting; clamping the cabin body casting on a repair device, removing the defects and processing notches according to the position information of the defects by using a milling head; cleaning the surface and periphery of the notches by using a laser cleaning head; adjusting the notches to a cladding position, filling the notches along a preset track by using a laser cladding head; removing the excess of the notches protruding from the notches by using the milling head, so that the upper surface of the notches is flush with the surrounding surface; repeating the cladding and excess removal steps until all the notches are repaired. The application realizes the precision of defect positioning and the automation of the excavation and removal process, lays the foundation for the automation of the repair process through the standardized notch design, integrates milling, cleaning and cladding in the same device, completes the whole process repair at one time, eliminates the frequent coordinate calibration steps, and significantly improves the repair efficiency and repair quality.

Description

Technical Field

[0001] This invention relates to the field of titanium alloy cabin casting repair, specifically to a laser cladding repair method for titanium alloy cabin castings. Background Technology

[0002] As spacecraft travel at ever greater speeds, increasingly stringent requirements are being placed on the lightweight and high-temperature performance of structural materials, leading to the wider application of titanium alloys. To control manufacturing costs and improve structural integrity, casting processes have become the preferred choice.

[0003] In the repair of titanium alloy cast structural components for spacecraft hulls, X-ray inspection is primarily employed, followed by manual comparison and marking of defect locations based on imaging films. This is followed by manual excavation to remove defects and manual TIG arc wire filling for repair. Due to the high strength and hardness of titanium alloys, manual excavation is difficult and labor-intensive. The manual TIG arc wire filling process also faces challenges such as low automation, heavy reliance on experience, a rough repair process, insufficient fine-grained control, large residual material after repair, and difficulty in manually grinding away the excess material. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a laser cladding repair method for titanium alloy cabin castings.

[0005] The laser cladding repair method for titanium alloy cabin castings provided by the present invention includes the following steps: Step S1: Obtain the location information of defects exceeding the standard in the titanium alloy cabin casting; Step S2: Clamp the titanium alloy cabin casting onto the repair equipment, and according to the location information of the defect exceeding the standard, use the milling head of the repair equipment to remove the defect and process it into a groove; Step S3: Use the laser cleaning head of the repair equipment to clean the surface and surrounding area of ​​the groove; Step S4: Adjust the groove to the welding position, and use the laser welding head of the repair equipment to fill the groove along the preset trajectory; Step S5: Use the milling head of the repair equipment to remove the excess material protruding from the groove, so that the upper surface of the groove is flush with the surrounding surface; Step S6: Repeat steps S4 and S5 until all slots are repaired. Step S7: Remove the titanium alloy cabin casting.

[0006] Preferably, the repair equipment includes an X-axis slide, a Y-axis slide rail, a Y-axis motion module, a Z-axis motion module, a worktable, a C-axis motion module, a milling head, a laser cleaning head, and a laser cladding head; The worktable is set on the X-axis slide, and a fixture is provided on the worktable for clamping the titanium alloy cabin casting. The C-axis motion module is installed on the worktable and is used to drive the titanium alloy cabin casting clamped on the fixture to rotate. The Y-axis slide rail is fixedly mounted on the X-axis slide table, the Y-axis motion module is slidably mounted on the Y-axis slide rail, the Z-axis motion module is slidably mounted on the Z-axis slide rail of the Y-axis motion module, and the milling head, laser cleaning head and laser cladding head are all mounted on the Z-axis motion module.

[0007] Preferably, the Y-axis motion module includes a first Y-axis motion module and a second Y-axis motion module, and the Z-axis motion module includes a first Z-axis motion module and a second Z-axis motion module; The milling head is mounted on the first Z-axis motion module, the first Z-axis motion module is mounted on the first Y-axis motion module, the laser cleaning head and the laser cladding head are mounted on the second Z-axis motion module, and the second Z-axis motion module is mounted on the second Y-axis motion module.

[0008] Preferably, in step S2, the shape of the groove is a spherical or cuboid; the radius of the spherical is not less than the defect depth, and the fillet radius of the cuboid is not less than R1mm.

[0009] Preferably, in step S4, the preset trajectory is a circular line or a parallel line, and the slot is filled by multiple layers and multiple channels.

[0010] Preferably, when the slot is a spherical body, the preset trajectory is a circular line; when the slot is a cuboid, the preset trajectory is a parallel line.

[0011] Preferably, the overlap rate of two adjacent weld layers is 20% to 40%.

[0012] Preferably, in step S1, obtaining the location information of excessive defects in the titanium alloy cabin casting includes: The origin and three-dimensional coordinate axes were marked on the titanium alloy cabin casting. The titanium alloy casting was inspected using CT to obtain a three-dimensional model of the casting and the three-dimensional coordinate information of the defects exceeding the standard. The origin and three-dimensional coordinate axes of the three-dimensional model were consistent with the markings on the titanium alloy cabin casting.

[0013] Preferably, in step S4, the process parameters for laser cladding are as follows: Laser power 1200~2000W, beam oscillation radius 1~2mm, oscillation frequency 150~200Hz, cladding speed 0.3~0.7m / min, powder feeding rate 6~20g / min, powder feeding carrier gas flow rate 3~6L / min.

[0014] Preferably, in step S4, the welding position is the top position of the repair device.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention obtains the location information of the defects exceeding the standard and then directly clamps the cabin casting onto the repair equipment. The milling head automatically removes the defects and processes them into grooves based on the defect location information, thereby achieving precise defect positioning and automation of the excavation and removal process. This significantly reduces the labor intensity of manual excavation and removal while improving the excavation and removal accuracy and surface quality.

[0016] 2. This invention automates and digitizes the repair process by processing the defects into standardized groove shapes and combining them with corresponding repair trajectories and repair techniques. This enables subsequent laser cleaning, laser cladding, and excess material processing to be carried out in a standardized process, ensuring the consistency and repeatability of repair quality.

[0017] 3. This invention integrates a milling head, a laser cleaning head, and a laser cladding head onto the same repair equipment. The entire repair process of excavation, cleaning, cladding, and machining of the cabin casting can be completed in one clamping. This shortens the turnaround time of the product between different equipment, eliminates frequent coordinate calibration steps, and significantly improves repair efficiency and repair quality.

[0018] 4. By integrating a C-axis motion module into the repair equipment, this invention can rotate and reposition the groove to the welding position before laser welding, ensuring that the laser welding head is always in the optimal working posture, thus guaranteeing the stability and consistency of the welding process. Combined with optimized process parameters, it achieves precise filling of the groove and ensures the metallurgical bonding quality between the welded layer and the base material.

[0019] 5. This invention obtains the three-dimensional coordinate information of defects exceeding the standard through CT detection, and establishes a unified coordinate system based on the coordinate origin and three-dimensional coordinate axes marked on the cabin casting. This achieves precise alignment between the defect detection data and the coordinate system of the repair equipment, eliminates the positioning error caused by manual comparison and marking in traditional X-ray detection, ensures the positional accuracy of milling and excavation, and avoids the problems of over-excavation or incomplete excavation. Attached Figure Description

[0020] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the overall structure of the repair equipment in this invention; Figure 2 This is a schematic diagram of the repair equipment structure from the main view angle in this invention; Figure 3This is a top-view structural diagram of the repair equipment structure in this invention; Figure 4 This is a schematic diagram of the repair device structure viewed from the left angle in this invention.

[0021] The diagram shows: Detailed Implementation

[0022] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0023] This invention discloses a laser cladding repair method for titanium alloy cabin castings. After obtaining the location information of defects exceeding standards, the cabin casting is directly clamped onto the repair equipment. A milling head automatically removes the defects and processes them into grooves based on the defect location information, achieving precise defect positioning and automation of the excavation and removal process. In one embodiment, a typical product structure of the titanium alloy cabin casting is as follows: the cabin has a total length of approximately 700mm, an outer diameter of approximately Φ200mm, is made of TC4 titanium alloy, and has a wall thickness of 4–8mm.

[0024] The laser cladding repair method for titanium alloy cabin castings provided by the present invention specifically includes the following steps: Step S1: Obtain the location information of defects exceeding the standard in the titanium alloy cabin casting.

[0025] In a preferred embodiment, the origin and three-dimensional coordinate axes are marked on the titanium alloy cabin casting. CT scans are then used to inspect the titanium alloy casting, obtaining a three-dimensional model of the casting and the three-dimensional coordinate information of any defects exceeding the standard. The origin and three-dimensional coordinate axes of the three-dimensional model are consistent with the markings on the titanium alloy cabin casting, ensuring a precise coordinate correspondence between the defect location information and the actual cabin casting.

[0026] Step S2: The titanium alloy cabin casting is clamped onto the repair equipment. Based on the location information of the excessive defects, the milling head 8 of the repair equipment is used to remove the defects and process them into grooves. The milling head 8 automatically locates the defect position based on the three-dimensional coordinate information of the defect, completely removes the material in the defect area, and processes the excavated pit into a regular groove shape, providing a standardized process basis for subsequent laser cleaning and laser cladding.

[0027] In a preferred embodiment, the groove is shaped as a spherical or cuboid. The radius of the spherical groove is not less than the defect depth to ensure that the defect is completely removed; the fillet radius of the cuboid groove is not less than R1mm to avoid stress concentration caused by sharp edges, and at the same time to facilitate uniform powder spreading and stable flow of the molten pool during laser cladding.

[0028] Step S3: The surface and surrounding area of ​​the groove are cleaned using the laser cleaning head 9 of the repair equipment. The laser cleaning head 9 emits a high-energy laser beam to irradiate the surface and surrounding area of ​​the groove, removing the oxide layer, oil, and microparticles on the surface and surrounding area of ​​the groove through the laser ablation effect, providing a clean metallurgical bonding surface for subsequent laser cladding, and ensuring the bonding strength between the cladding layer and the base material.

[0029] Step S4: Adjust the groove to the welding position, and use the laser welding head 10 of the repair equipment to fill the groove along the preset trajectory.

[0030] In a preferred embodiment, the welding position is the top position (i.e., the 12 o'clock position) of the repair equipment. The chamber casting is rotated by the C-axis motion module 7 so that the groove to be repaired is in the top position. At this time, the laser welding head 10 is aligned with the groove from directly above. During the welding process, the molten pool remains stable under the action of gravity, which is beneficial to the uniformity and consistency of the weld layer forming quality.

[0031] In a preferred embodiment, the preset trajectory is a circular line or a parallel line, which fills the slot through multiple layers and multiple passes. When the slot is a spherical body, the welding trajectory is a circular line, starting from the bottom of the slot and filling outwards layer by layer with a gradually expanding circular path; when the slot is a cuboid, the welding trajectory is a parallel line, filling out layer by layer along the length of the slot with a parallel path.

[0032] In a preferred embodiment, the overlap rate between two adjacent weld passes is 20% to 40%. An appropriate overlap rate ensures a good metallurgical bond between adjacent weld passes, avoids defects such as incomplete fusion or slag inclusions between passes, and ensures the surface smoothness after the groove is filled.

[0033] In practical operation, the process parameters for laser cladding are as follows: laser power 1200–2000W, beam oscillation radius 1–2mm, oscillation frequency 150–200Hz, cladding speed 0.3–0.7m / min, powder feeding rate 6–20g / min, and powder-feeding carrier gas flow rate 3–6L / min. Through the oscillating scanning of the laser beam, the molten pool is sufficiently stirred and a gas escape channel is provided, effectively reducing the porosity of the cladding layer. The matching of the powder feeding rate and carrier gas flow rate ensures the stability and uniformity of powder delivery. In a preferred example, for a titanium alloy casting with a total length of approximately 700mm, an outer diameter of approximately Φ200mm, and a material of TC4 titanium alloy with a wall thickness of 4–8mm, the following process parameters are used: laser power 1500W, beam oscillation radius 1.5mm, oscillation frequency 200Hz, cladding speed 0.5m / min, powder feeding rate 15g / min, and powder-feeding carrier gas flow rate 4L / min.

[0034] Step S5: Using the milling head 8 of the repair equipment, the excess material protruding from the groove is removed, making the upper surface of the groove flush with the surrounding surface. After the fusion is completed, there is usually a small amount of fusion layer excess material at the groove that is higher than the surrounding surface. The protruding part is precisely removed by milling head 8 to restore the original contour and dimensional accuracy of the cabin casting surface.

[0035] Step S6: Repeat steps S4 and S5 until all slots are repaired. When there are multiple defects exceeding the standard in the hull casting, laser cladding and allowance machining are performed on the slots corresponding to each defect in sequence until all are repaired.

[0036] Step S7: Remove the titanium alloy hull casting. After all grooves have been repaired, remove the hull casting from the workbench of the repair equipment to complete the entire repair process.

[0037] like Figures 1-4 As shown, the repair equipment includes an X-axis slide 1, a Y-axis slide rail, a Y-axis motion module, a Z-axis motion module, a worktable 6, a C-axis motion module 7, a milling head 8, a laser cleaning head 9, and a laser cladding head 10. The worktable 6 is mounted on the X-axis slide 1 and is equipped with a fixture for clamping the titanium alloy cabin casting. The C-axis motion module 7 is mounted on the worktable 6 and drives the titanium alloy cabin casting clamped in the fixture to rotate. The Y-axis slide rail is fixedly mounted on the X-axis slide 1, the Y-axis motion module is slidably mounted on the Y-axis slide rail, and the Z-axis motion module is slidably mounted on the Z-axis slide rail of the Y-axis motion module. The milling head 8, the laser cleaning head 9, and the laser cladding head 10 are all mounted on the Z-axis motion module.

[0038] In a preferred embodiment, the Y-axis motion module includes a first Y-axis motion module 2 and a second Y-axis motion module 3, and the Z-axis motion module includes a first Z-axis motion module 4 and a second Z-axis motion module 5. The milling head 8 is mounted on the first Z-axis motion module 4, which is mounted on the first Y-axis motion module 2; the laser cleaning head 9 and the laser cladding head 10 are mounted on the second Z-axis motion module 5, which is mounted on the second Y-axis motion module 3. Through this independent drive layout of dual Y-axis and dual Z-axis, the milling head 8, laser cleaning head 9, and laser cladding head 10 are each driven by independent motion modules, ensuring they do not interfere with each other during the repair process and can independently complete their respective motion trajectories, thus guaranteeing the accuracy and efficiency of each process.

[0039] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0040] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for laser cladding repair of titanium alloy cabin castings, characterized in that, Includes the following steps: Step S1: Obtain the location information of defects exceeding the standard in the titanium alloy cabin casting; Step S2: Clamp the titanium alloy cabin casting onto the repair equipment, and according to the location information of the defect exceeding the standard, use the milling head (8) of the repair equipment to remove the defect and process it into a groove; Step S3: Use the laser cleaning head (9) of the repair equipment to clean the surface and surrounding area of ​​the groove; Step S4: Adjust the slot to the welding position, and use the laser welding head (10) of the repair equipment to fill the slot along the preset trajectory; Step S5: Use the milling head (8) of the repair equipment to remove the excess material protruding from the groove, so that the upper surface of the groove is flush with the surrounding surface; Step S6: Repeat steps S4 and S5 until all slots are repaired. Step S7: Remove the titanium alloy cabin casting.

2. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, The repair equipment includes an X-axis slide (1), a Y-axis slide rail, a Y-axis motion module, a Z-axis motion module, a worktable (6), a C-axis motion module (7), a milling head (8), a laser cleaning head (9), and a laser cladding head (10). The worktable (6) is set on the X-axis slide (1), and the worktable (6) is equipped with a fixture for clamping the titanium alloy cabin casting. The C-axis motion module (7) is installed on the worktable (6) and is used to drive the titanium alloy cabin casting clamped on the fixture to rotate. The Y-axis slide rail is fixedly installed on the X-axis slide table (1), the Y-axis motion module is slidably installed on the Y-axis slide rail, the Z-axis motion module is slidably installed on the Z-axis slide rail of the Y-axis motion module, and the milling head (8), laser cleaning head (9) and laser cladding head (10) are all installed on the Z-axis motion module.

3. The laser cladding repair method for titanium alloy cabin castings according to claim 2, characterized in that, The Y-axis motion module includes a first Y-axis motion module (2) and a second Y-axis motion module (3), and the Z-axis motion module includes a first Z-axis motion module (4) and a second Z-axis motion module (5). The milling head (8) is mounted on the first Z-axis motion module (4), the first Z-axis motion module (4) is mounted on the first Y-axis motion module (2), the laser cleaning head (9) and the laser cladding head (10) are mounted on the second Z-axis motion module (5), and the second Z-axis motion module (5) is mounted on the second Y-axis motion module (3).

4. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, In step S2, the groove is shaped like a sphere or a cuboid; the radius of the sphere is not less than the defect depth, and the fillet radius of the cuboid is not less than R1mm.

5. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, In step S4, the preset trajectory is a circular line or a parallel line, which is filled into the slot through multiple layers and multiple channels.

6. The laser cladding repair method for titanium alloy cabin castings according to claim 5, characterized in that, When the slot is a spherical body, the preset trajectory is a circular line; when the slot is a cuboid, the preset trajectory is a parallel line.

7. The laser cladding repair method for titanium alloy cabin castings according to claim 5, characterized in that, The overlap rate between two adjacent weld layers is 20% to 40%.

8. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, In step S1, obtaining the location information of excessive defects in the titanium alloy cabin casting includes: The origin and three-dimensional coordinate axes were marked on the titanium alloy cabin casting. The titanium alloy casting was inspected using CT to obtain a three-dimensional model of the casting and the three-dimensional coordinate information of the defects exceeding the standard. The origin and three-dimensional coordinate axes of the three-dimensional model were consistent with the markings on the titanium alloy cabin casting.

9. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, In step S4, the process parameters for laser cladding are as follows: Laser power 1200~2000W, beam oscillation radius 1~2mm, oscillation frequency 150~200Hz, cladding speed 0.3~0.7m / min, powder feeding rate 6~20g / min, powder feeding carrier gas flow rate 3~6L / min.

10. The laser cladding repair method for titanium alloy cabin castings according to claim 1, characterized in that, In step S4, the welding position is the top position of the repair device.

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