A PCD tool and layered welding process

Abstract

The present invention discloses a PCD tool and a layered welding process, relating to the technical field of tool welding. The laser welding process for PCD tools is essentially to heat the brazing material with the high thermal energy of a high-energy laser beam, and complete the welding process by laminating PCD composite sheets. In order to avoid problems such as graphitization of the PCD composite sheets caused by the high thermal energy of the high-energy laser beam, the present invention optimizes the overall welding tooling. The essence of the present invention is: first, the installation method of the PCD composite sheet relative to the tool base is changed so that the heating process of the laser beam does not directly affect the PCD composite sheet, and only the hot melt temperature of the brazing material layer is maintained. Based on this, a rotation method of the PCD composite sheet relative to the tool base is proposed, the purpose of which is to ensure that the PCD composite sheet is fully attached to the tool base and the welding quality is analyzed based on the electrical sensing method. The key purpose is to improve the welding quality of the PCD tool by maintaining the lamination method of the two.

Description

Technical Field

[0001] The present invention relates to the technical field of tool welding, and in particular to a PCD tool and a layered welding process. Background Art

[0002] PCD cutting tools are superhard cutting tools with polycrystalline diamond as cutting edge. Their structure is basically similar to that of conventional cutting tools. The difference is that the processed PCD composite sheet is integrated with the conventional cutting tool by welding. Please refer to the relevant content in the publication numbers CN116117334A and CN104440004A.

[0003] Laser welding is the main welding method. You can refer to the relevant content in the publication number CN108213735A. A high-energy laser beam is focused on the joint surface of the PCD composite sheet and the tool body (brass), and the instantaneous high temperature (up to thousands of degrees Celsius) causes the brazing material to melt and fuse. After cooling, a bond is formed between the PCD composite sheet and the tool body. It should be noted that the welding process needs to avoid the problem of graphitization caused by the laser beam / spot affecting the PCD composite sheet, and it is also necessary to ensure that the brazing material is fully heated and melted. The overall process also needs to be explained: the laser beam has high energy and has the effects of high heat and high cooling difference. The thermal expansion mismatch between the brazing material and the substrate aggravates stress. The molten pool is deep and narrow and cools quickly, making it difficult for gas to escape. Porosity or unfused areas are likely to remain in the weld. In this process, it is particularly important to note that the degree of fit between the PCD composite sheet and the tool will also aggravate the impact caused by the above temperature and affect the stability after welding. This application proposes a solution to this problem. Summary of the Invention

[0004] The purpose of the present invention is to provide a PCD tool and a layered welding process. The laser welding forming process of the PCD tool is described. Considering the energy characteristics of the laser beam, the specific welding process may indirectly affect the PCD composite sheet and cause graphitization problems. The clamping force during the welding process may also affect the stability and tool quality after welding.

[0005] The objectives of the present invention can be achieved through the following technical solutions: a layered welding process for PCD tools, which is applied to the welding process of PCD tools and uses a tool assembly and a high-energy laser assembly, wherein the tool assembly includes a tool table and a coupling head, the center point of the tool table is set as the tool base placement position, and the tool table is provided with multiple movable arc heads and hollow arc strips at the peripheral positions corresponding to the tool base placement position, and the layered welding process includes a pre-installation stage, a high-energy hot melt stage, and a global patch stage;

[0006] In the pre-assembly stage, a PCD composite sheet is first placed on the hollow arc strip, and the tool base is installed on the tool base placement position. Finally, a brazing layer corresponding to the PCD composite sheet is coated on the tool base.

[0007] The solder layer is directly heated by a high-energy laser assembly during the high-energy hot melting stage;

[0008] In the global patch stage, the tool base and the active arc head rotate synchronously to make the PCD composite sheet fully contact with the brazing material layer, and the rotation directions of the tool base and the active arc head are opposite.

[0009] It is further configured as follows: the tooling table is mounted on a coupling head, a driving motor is mounted at the center point of the coupling head, and a mounting shaft corresponding to a tool base is mounted at the output end of the driving motor.

[0010] It is further configured as follows: a plurality of sliders corresponding to the hollow arc strips are provided on the workbench, and a linear drive structure corresponding to the hollow arc strip is installed on the workbench, the sliders are slidably connected on the workbench along the diameter direction of the corresponding tool base through the linear drive structure, and the hollow arc strips are installed on the sliders in a vertical state.

[0011] It is further configured as follows: a cooperating gear plate is rotatably mounted on the lower outer wall of the workbench, and a reversing gear set is provided between the mounting shaft and the cooperating gear plate.

[0012] It is further configured that: an arc-shaped slide is provided in the internal position of the cooperative gear plate corresponding to the movable arc head, and a mounting column corresponding to the movable arc head is vertically mounted on the arc-shaped slide.

[0013] It is further configured as follows: the movable arc head is slidably connected along the center point of the workbench in the cooperative gear plate, and the cooperative gear plate is equipped with an electrical sensing structure in the internal position corresponding to the two end positions of the movable arc head.

[0014] It is further configured as follows: the reversing gear set includes a driving gear and a transfer gear arranged on the mounting shaft, the driving gear and the transfer gear are externally meshed, the transfer gear is located in the middle position between the inner wall of the cooperating gear plate and the driving gear, and the transfer gear is rotationally connected to the workbench, and the transfer gear and the inner wall of the cooperating gear plate are internally meshed.

[0015] It is further configured as follows: an elliptical cavity is opened inside the hollow arc bar, and the upper end portion of the movable arc head is arranged in a forward extension shape along the direction close to the hollow arc bar.

[0016] It is further provided as follows: a PCD tool comprises a tool base and a PCD composite sheet, wherein the PCD composite sheet is mounted on the tool base via a brazing material layer.

[0017] The present invention has the following beneficial effects:

[0018] 1. The processing of PCD tools is based on conventional laser welding. Its essence is to heat the brazing material layer with the high heat energy of a high-energy laser beam. After the brazing material layer cools down, the PCD composite sheet and the tool substrate are integrated. The overall welding process is improved. First, the installation method of the PCD composite sheet relative to the tool substrate is changed. During the heating process of the high-energy laser beam, there is no obvious contact between the PCD composite sheet and the PCD composite sheet. The purpose is to ensure that the heating process of the laser beam does not directly affect the PCD composite sheet, but only maintain the hot melt temperature of the brazing material layer, so as to avoid the heat generated by the laser beam directly affecting the PCD composite sheet and causing problems such as graphitization.

[0019] 2. Based on the above content, a global fitting process of co-directional rotation and approach is proposed for the installation process of the tool base. Its essence is to ensure that the brazing material layer on the tool base and the PCD composite sheet on the hollow arc strip are close to each other at the same time. In this process, its purpose is to ensure that the PCD composite sheet is fully attached to the tool base, and to utilize the relevant data generated by the sliding process between the movable arc head and the arc slide relative to the electrical sensing structure, which is specifically manifested as the sliding direction, sliding speed and sliding stroke of the arc slide. In this way, the degree of fitting of the PCD composite sheet relative to the tool base is sensed to ensure the molding quality of the overall PCD tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a structural schematic diagram of a PCD tool proposed in the present invention;

[0022] Figure 2 This is a schematic structural diagram of a tooling table in a layered welding process for PCD cutting tools proposed by the present invention;

[0023] Figure 3 for Figure 2 The cutaway view of the workbench;

[0024] Figure 4 Based Figure 3 The local split diagram of ;

[0025] Figure 5 Schematic diagram of the structure of the cooperative gear plate in the present invention;

[0026] Figure 6 For the present invention Figure 6 Partial cutaway view;

[0027] Figure 7 for Figure 2 Top view of .

[0028] In the figure: 1. Tool base; 2. PCD composite sheet; 3. Workbench; 4. Slider; 5. Movable arc head; 6. Coupling head; 7. Hollow arc bar; 8. Electrical sensing structure; 9. Drive motor; 10. Cooperative gear plate; 11. Linear drive structure; 12. Reversing gear set; 13. Mounting column; 14. Arc slide. DETAILED DESCRIPTION

[0029] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] Example 1: The laser welding process of PCD tools is described. Considering the energy characteristics of the laser beam, the specific welding process may indirectly affect the PCD composite sheet and cause graphitization problems. The clamping force during the welding process may also affect the stability and tool quality after welding. In this regard, the following technical solutions are proposed:

[0031] Reference Figures 1 to 7 In this embodiment, a layered welding process for a PCD tool is applied to the welding process of the PCD tool and uses a tool assembly and a high-energy laser assembly. The tool assembly includes a tool table 3 and a coupling head 6. The center point of the tool table 3 is set as the tool base placement position, and the tool table 3 is provided with multiple movable arc heads 5 and hollow arc strips 7 at the peripheral positions corresponding to the tool base placement position. The layered welding process includes a pre-installation stage, a high-energy hot melt stage, and a global patch stage.

[0032] In the pre-assembly stage, a PCD composite sheet is first placed on the hollow arc strip 7, and a tool base is installed on the tool base placement position. Finally, a brazing layer corresponding to the PCD composite sheet is coated on the tool base.

[0033] The solder layer is directly heated by a high-energy laser assembly during the high-energy hot melting stage;

[0034] In the global patch stage, the tool base and the movable arc head 5 rotate synchronously to make the PCD composite sheet fully contact with the brazing material layer, and the rotation directions of the tool base and the movable arc head 5 are opposite. A PCD tool includes a tool base 1 and a PCD composite sheet 2, and the PCD composite sheet 2 is mounted on the tool base 1 through the brazing material layer.

[0035] Basic principle: refer to Figure 1 A brief description of PCD tool is given. Its essence is the tool base 1, and the PCD composite sheet 2 is installed at its designated position. The present invention does not explain the types or specifications of the tool base 1 and PCD composite sheet 2. As for the processing process of PCD tool, the present invention specifically takes the most widely used laser welding technology as an example and briefly explains the principle of PCD laser welding technology: using high energy density (usually up to 10 6 A focused laser beam with a power of -10¹²W / cm² is used as a heat source. By converting light energy into heat energy, the material in the welding area is rapidly heated to a molten state. ‌24 In PCD tool welding, the laser preferentially acts on the carbide substrate or the solder interface, avoiding direct irradiation of the PCD layer, thereby protecting its thermal stability. However, it is understood that if the laser directly irradiates the PCD composite sheet 2 during the specific welding process, it will directly damage the PCD composite sheet 2. Therefore, the present invention proposes technical improvements for layered welding:

[0036] Reference Figure 7 and Figure 3 It can be seen that the PCD composite sheet 2 is not placed directly on the tool base 1 but directly on the hollow arc strip 7. Secondly, the corresponding brazing material layer of the PCD composite sheet 2 is coated on the corresponding position on the tool base 1. Then, when welding begins, the high-energy laser assembly directly heats the position of the brazing material layer. The relevant structure of the high-energy laser assembly is not described in this invention, and the overall tooling table 3 is installed on the five-axis motion structure through the coupling head 6. Its purpose is to cooperate with the heating process of the high-energy laser beam. After each brazing material layer is completed by laser heating and hot melting, the tool base 1 is first rotated in a directional manner under the action of the drive motor 9. The essence is to gradually move the hot-melted brazing material layer closer to the PCD composite sheet 2 so that the PCD composite sheet 2 is completely attached to the brazing material layer.

[0037] Example 2: Supplementary explanation based on the pre-installation stage and global patch stage in Example 1:

[0038] The workbench 3 is installed on the coupling head 6, and a driving motor 9 is installed at the center point of the coupling head 6. The mounting shaft corresponding to the tool base is installed at the output end of the driving motor 9. A plurality of sliders 4 corresponding to the hollow arc strips 7 are provided on the workbench 3, and a linear driving structure 11 corresponding to the hollow arc strips 7 is installed on the workbench 3. The slider 4 is slidably connected on the workbench 3 along the diameter direction of the corresponding tool base through the linear driving structure 11. The hollow arc strip 7 is installed on the slider 4 in a vertical state. A cooperating gear plate 10 is rotatably installed on the lower outer wall of the workbench 3, and a reversing gear set 12 is provided between the mounting shaft and the cooperating gear plate 10. An arc slide 14 is provided in the internal position of the cooperating gear plate 10 corresponding to the movable arc head 5, and a mounting column 13 corresponding to the movable arc head 5 is installed vertically on the arc slide 14.

[0039] Solution description: Although the present invention does not limit the structure of the tool base 1, it is necessary to pay attention to the possible interference problem between the PCD composite sheet 2 and the tool base 1. To this end, the present invention adds a slider 4 corresponding to the hollow arc strip 7 to the tooling table 3. The purpose is to ensure that the hollow arc strip 7 can only slide along the diameter direction of the tool base 1. Therefore, in the pre-installation stage, the linear drive structure 11 is required to drive the slider 4 to move in a directional manner to ensure that the PCD composite sheet 2 installed on the hollow arc strip 7 is away from the tool base 1. Therefore, the high-energy laser beam will never interfere with the heating process of the brazing material layer on the PCD composite sheet. On the contrary, when the PCD composite sheet 2 needs to be attached to the tool base 1, the slider 4 moves in the opposite direction to ensure that the PCD composite sheet 2 moves to the corresponding position.

[0040] In the global patch stage, the tool base is essentially driven by the driving motor 9 to rotate in a directional manner, which can be understood as: the solder layer in a molten state contacts the PCD composite sheet 2. In this process, further reference is made to Figure 4 and Figure 5 To explain, it is essentially driven by the driving gear on the driving motor 9, and the reversing gear set 12 in the present invention is mainly driven by the transfer gear for reversing. If the driving gear rotates in the clockwise direction, the transfer gear will rotate in the counterclockwise direction, and according to the principle of internal meshing, the cooperating gear disk 10 will also rotate counterclockwise. Each active arc head 5 rotates counterclockwise under the action of the cooperating gear disk 10, which can be directly understood as: the PCD composite sheet 2 and the solder layer on the tool substrate 1 are close to each other at the same time.

[0041] Example 3: Further explanation of the global patch stage:

[0042] The movable arc head 5 is slidably connected in the cooperative gear disk 10 along the center point of the workbench 3. The cooperative gear disk 10 is equipped with an electrical sensing structure 8 in the internal position corresponding to the two end positions of the movable arc head 5. The reversing gear set 12 includes a driving gear and a transfer gear arranged on the mounting shaft. The driving gear and the transfer gear are externally meshed. The transfer gear is located in the middle position between the inner wall of the cooperative gear disk 10 and the driving gear, and the transfer gear is rotationally connected to the workbench 3. The transfer gear and the inner wall of the cooperative gear disk 10 are internally meshed. An elliptical cavity is opened inside the hollow arc bar 7, and the upper end part of the movable arc head 5 is arranged in a forward extension shape along the direction close to the hollow arc bar 7.

[0043] Solution description: Based on the technical content of Example 2, the PCD composite sheet 2 can be installed on the hollow arc strip 7 in a temporary fixed manner. Its essence is that it only needs to maintain a short residence time of the PCD composite sheet 2 on the hollow arc strip 7. Ultimately, it still needs to be welded to the tool base 1 using a brazing material layer. This part will not be focused on in this embodiment.

[0044] It should be noted that: Figure 5 The structural characteristics of the hollow arc strip 7 are that an elliptical cavity is opened in its internal position, so the hollow arc strip 7 can be slightly bent. Specifically, the hollow arc strip 7 is slightly bent by the movable arc head 5. The following supplementary explanation is given:

[0045] S1: In essence, the hollow arc strip 7 is only used as a temporary mounting structure for the PCD composite sheet 2, and the hollow arc strip 7 does not rotate. Therefore, when the tool base 1 and the movable arc head 5 rotate in the opposite direction, the position of the hollow arc strip 7 does not change. Instead, the tool base 1 and the movable arc head 5 move towards the hollow arc strip 7 at the same time. Only when the tool base 1 and the movable arc head 5 are completely close to the hollow arc strip 7 can the PCD composite sheet 2 be completely fitted into the brazing material layer.

[0046] S2: Reference Figure 6Explanation: The movable arc head 5 is mainly installed through the mounting column 13, and the mounting column 13 is connected through the arc slide 14, and the arc slide 14 slides in the arc direction in the cooperative gear plate 10, so as to refer to S1 for improvement: If the movable arc head 5 rotates counterclockwise, and when the movable arc head 5 does not contact the hollow arc bar 7, the arc slide 14 does not slide significantly in the cooperative gear plate 10 or slides with a small amplitude, until the arc slide 14 contacts the hollow arc bar 7, the arc slide 14 slides to a greater extent, which can be used The electrical sensing structure 8 senses the sliding direction, sliding speed, and sliding stroke of the arc-shaped slide 14 in real time during its sliding process. It should be briefly explained that, because the entire laser welding process may need to be performed in a vacuum environment, the present invention mainly uses electricity as a detection means. The electrical sensing structure 8 is essentially a resistive sensing structure. The main structure of the electrical sensing structure 8 is an arc-shaped resistance rod, and the arc-shaped slide 14 is also conductive and slides freely on the arc-shaped resistance rod. Thus, the sensing process of the sliding direction, sliding speed, and sliding stroke of the arc-shaped slide 14 during its sliding process is realized by using a resistive method.

[0047] S3: A supplementary explanation for S2 is that: because the hollow arc bar 7 is in a relatively fixed state relative to the setting position of the tool base, the maximum rotation angle of the tool base 1 can be directly grasped. In theory, the movable arc platform 5 has the same rotation angle as the tool base 1, but because the arc slide 14 has an arc sliding process in the cooperative gear plate 10, the movable arc platform 5 will slide further. In this process, the sliding direction, sliding speed and sliding stroke of the arc slide 14 are sensed in real time by the electrical sensing structure 8, and the degree of fit between the PCD composite sheet 2 and the tool base 1 is obtained after analysis. This part requires a specific analysis system and is not introduced in detail in the present invention. A brief introduction is: after the PCD composite sheet 2 is fully in contact with the tool base 1, the sliding speed and sliding direction of the arc slide 14 tend to be relatively stable. This is specifically because when the PCD composite sheet 2 and the tool base 1 are not in full contact, the sliding speed of the arc slide 14 fluctuates significantly.

[0048] In summary: The essence of the laser welding process of PCD tools is to heat the brazing material with the high thermal energy of a high-energy laser beam, and complete the welding process by bonding the PCD composite sheet. In order to avoid the problem of graphitization of the PCD composite sheet caused by the high thermal energy of the high-energy laser beam, the present invention optimizes the overall welding tooling. Its essence is: first, the installation method of the PCD composite sheet relative to the tool base is changed, so that the heating process of the laser beam will not directly affect the PCD composite sheet, and only the hot melt temperature of the brazing material layer is maintained. On this basis, a rotation method of the PCD composite sheet relative to the tool base is proposed, the purpose of which is to ensure that the PCD composite sheet is fully attached to the tool base and analyze the welding quality based on the electrical sensing method. The key purpose is to improve the welding quality of the PCD tool by maintaining the bonding method of the two.

[0049] The above contents are merely examples and explanations of the structure of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they shall fall within the scope of protection of the present invention.

[0050] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0051] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A layered welding process for PCD tools, which is applied in the welding process of PCD tools and uses a tooling assembly and a high-energy laser assembly, and is characterized in that: The tooling assembly includes a tooling table and a coupling head. The center point of the tooling table is set as the tool base placement position, and the tooling table is provided with multiple movable arc heads and hollow arc strips at the peripheral positions corresponding to the tool base placement position. The layered welding process includes a pre-installation stage, a high-energy hot melt stage, and a global patch stage. In the pre-assembly stage, a PCD composite sheet is first placed on the hollow arc strip, and the tool base is installed on the tool base placement position. Finally, a brazing layer corresponding to the PCD composite sheet is coated on the tool base. The solder layer is directly heated by a high-energy laser assembly during the high-energy hot melting stage; In the global patch stage, the tool base and the active arc head rotate synchronously to make the PCD composite sheet fully contact with the brazing material layer, and the rotation directions of the tool base and the active arc head are opposite; The drive shaft is installed on the tooling table, and a plurality of sliders corresponding to the hollow arc strips are provided on the tooling table, and a linear drive structure corresponding to the hollow arc strips is installed on the tooling table. The sliders are slidably connected on the tooling table along the diameter direction of the corresponding tool base through the linear drive structure. The hollow arc strip is mounted on the slider in a vertical state, and a cooperating gear plate is rotatably installed on the lower outer wall of the tooling table. A reversing gear set is provided between the mounting shaft and the cooperating gear plate. An arc slide is provided in the internal position of the cooperating gear plate corresponding to the movable arc head, and a mounting column corresponding to the movable arc head is vertically installed on the arc slide, an elliptical cavity is opened inside the hollow arc strip, and the upper end part of the movable arc head is arranged in a forward extension shape along the direction close to the hollow arc strip.

2. The layered welding process of a PCD tool according to claim 1, characterized in that: The movable arc head is slidably connected along the center point of the workbench in the cooperative gear plate, and the cooperative gear plate is equipped with an electrical sensing structure in the internal position corresponding to the two end positions of the movable arc head.

3. The layered welding process of a PCD tool according to claim 1, characterized in that: The reversing gear set includes a driving gear and a transfer gear arranged on the mounting shaft, the driving gear and the transfer gear are externally meshed, the transfer gear is located between the inner wall of the cooperating gear plate and the driving gear, and the transfer gear is rotationally connected to the workbench, and the transfer gear and the inner wall of the cooperating gear plate are internally meshed.

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