A method for manufacturing a composite dry cutting self-lubricating PCD turning tool
By preparing bottle-shaped cross-section microtextures on the surface of PCD turning tools and combining vacuum negative pressure infiltration and high-temperature curing, the problem of lubricant being easily discharged in dry cutting of composite materials is solved, achieving stable anchoring of lubricant, reducing tool wear, and improving machining quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHANGCHUN UNIV OF SCI & TECH
- Filing Date
- 2026-04-09
- Publication Date
- 2026-06-30
AI Technical Summary
In existing dry cutting processes of composite materials, PCD tools suffer severe wear due to high cutting temperatures. Lubricant powder is easily expelled by fibrous chips, which cannot effectively reduce friction and affects the quality of the machined surface.
Laser processing was used to prepare bottle-shaped cross-section microtextures on the surface of PCD turning tools. Combined with vacuum negative pressure infiltration and high temperature curing, the solid lubricant was ensured to be stably anchored in the microtexture and migrated to the tool surface through chip contact to form lubricating contact, reducing mechanical and chemical interactions.
It effectively reduces PCD tool wear, improves the surface quality of the machined material, and provides a high surface quality machining guarantee for dry cutting of composite materials.
Smart Images
Figure CN122299342A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of turning tool manufacturing technology, and more specifically, to a method for manufacturing a composite dry cutting self-lubricating PCD turning tool. Background Technology
[0002] Composite materials, composed of carbon fiber reinforcement, pyrolytic carbon interface, and silicon carbide ceramic matrix, possess advantages such as high strength, high hardness, impact resistance, oxidation resistance, high temperature resistance, and friction resistance. They are widely used in high-temperature components such as combustion chambers, guide vanes, and nozzles in aerospace and engine parts. The manufacturing of composite materials for functional components requires machining, and the surface quality of the machined parts significantly impacts the mechanical properties and service performance of these precision components.
[0003] In precision dry turning of composite materials, cutting tools with good sharpness and edge strength are required, and polycrystalline diamond (PCD) tools are mostly used for cutting. In precision dry turning, the high cutting temperature causes carbon diffusion at the interface between the PCD tool and the chip, leading to accelerated diffusion wear of the tool, insufficient cutting edge sharpness, and poor chip breaking ability, resulting in a decline in the surface quality of the machined material.
[0004] Since composite cutting is a dry cutting process, solid lubrication is required on the tool surface for friction reduction and chip removal. Existing technologies only address filling micro-pits on the tool surface with MoS2 solid lubricant powder. However, in this method, the lubricant powder is easily displaced from the micro-pits by the fibrous chips of the composite material, preventing the lubricant powder from being effectively fixed within the micro-pits and thus losing its friction-reducing and lubricating capabilities. Therefore, a method for manufacturing a self-lubricating PCD turning tool for dry cutting of composite materials is proposed to solve one of the aforementioned technical problems. Summary of the Invention
[0005] The purpose of this application is to provide a method for manufacturing a composite dry cutting self-lubricating PCD turning tool, which can solve at least one of the technical problems mentioned above. The specific solution is as follows: According to a specific embodiment of this application, this embodiment provides a method for manufacturing a composite dry cutting self-lubricating PCD turning tool, including: Set the structural parameters and surface microtexture parameters of the PCD turning tool, wherein the cross-section of the surface microtexture morphology is a variable cross-section; set the laser parameters for machining the PCD turning tool, and modulate the duration of the laser output pulse; The PCD turning tool is machined according to the laser parameters and the structural parameters and surface microtexture parameters of the PCD turning tool; After the diluent and solid lubricant are mixed and diluted to form a slurry, it is applied to the surface of the PCD turning tool and then subjected to vacuum negative pressure penetration and high temperature curing. After the PCD turning tool has cooled down, remove the residual slurry from the surface of the PCD turning tool.
[0006] In some embodiments, the structural parameters of the PCD turning tool include: tool tip radius and tool tip angle; the surface microtexture parameters include: the distance between the surface microtexture and the main cutting edge, the distance between the surface microtexture and the secondary cutting edge, and the distance within the surface microtexture.
[0007] In some embodiments, the laser parameters of the PCD turning tool include: laser power, laser frequency, number of processing operations, and processing time.
[0008] In some embodiments, the machining of the PCD turning tool includes: automatically focusing the PCD turning tool surface image based on the hill-climbing method; calculating the sharpness using the gradient sum sharpness operator; and after focusing, adjusting the laser defocus to prepare the surface microtexture.
[0009] In some embodiments, machining the PCD turning tool includes machining the PCD turning tool structure according to the time delay between laser pulse outputs and the time delay set between machining operations.
[0010] In some embodiments, the delay time between laser pulse outputs is 1~100μs, and the delay time between processing is set to 100μs~1ms.
[0011] In some embodiments, the surface microtexture morphology is a pit structure, with the waist diameter being 0.5 to 0.8 times the upper opening diameter and the bottom diameter being 0.8 to 1.2 times the upper opening diameter.
[0012] In some embodiments, the thickness of the mixed slurry scraped onto the surface of the PCD turning tool is 50~100μm.
[0013] In some embodiments, the pressure of the vacuum negative pressure osmosis is 10. -1 ~10 -2 Pa.
[0014] In some embodiments, the high-temperature curing temperature is 200~300 degrees Celsius, and the holding time is 1~2 hours.
[0015] Compared with the prior art, the above-described solutions of this application have at least the following beneficial effects: This application discloses a method for manufacturing a self-lubricating PCD turning tool for dry cutting of composite materials. The method involves preparing a bottle-shaped cross-section microtexture on the surface of the PCD tool. Through negative pressure infiltration and high-temperature curing, the solid lubricant in the PCD tool is stably anchored within the microtexture. During dry cutting of the composite material, the solid lubricant migrates from the microtexture to the tool surface through tool-chip contact, forming a lubricating contact at the tool-chip interface. This reduces the mechanical and chemical interactions between the PCD tool and the composite material, thereby reducing tool wear and improving the surface quality of the machined material. This provides technical support for high-surface-quality machining of composite materials during dry cutting. Attached Figure Description
[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings: Figure 1 A flowchart illustrating a method for manufacturing a composite dry cutting self-lubricating PCD turning tool, provided in an embodiment of the present invention; Figure 2 A three-dimensional structural diagram of a composite material dry cutting self-lubricating PCD turning tool provided in an embodiment of the present invention; Figure 3 A laser output pulse time modulation diagram for a composite material dry cutting self-lubricating PCD turning tool manufacturing method provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the surface texture cross-section of a composite dry cutting self-lubricating PCD turning tool provided in an embodiment of the present invention; Figure 5 A cross-sectional view of the surface texture of a composite dry cutting self-lubricating PCD turning tool provided in an embodiment of the present invention; Figure 6 is an effect diagram of a composite material dry cutting self-lubricating PCD turning tool provided in an embodiment of the present invention. Detailed Implementation
[0017] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0018] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.
[0019] The following is in conjunction with the appendix Figure 1 -6. Detailed description of optional embodiments of the present invention.
[0020] According to specific embodiments of the present invention, such as Figure 1 As shown, this application provides a method for manufacturing a composite dry cutting self-lubricating PCD turning tool, comprising: The structural parameters and surface microtexture parameters of the PCD turning tool are set. For example, the surface microtexture is a micro-dimple texture. The cross-section of the surface microtexture is a variable cross-section; for example, the vertical cross-section is a bottle-shaped variable cross-section. Conventional laser-focused machining produces a V-shaped cross-section. After the solid lubricant is filled, voids are generated at the bottom of the texture. During the friction-shear induced lubrication film process, the top lubricant layer is prone to collapse or peeling, significantly reducing lubrication life. The bottle-shaped cross-section has a better structural interlocking effect, and the variable cross-section design can effectively control the lubricant extrusion rate. Under pressure, it can maintain the filling shape, facilitating the long-term generation of a solid lubricant film. The laser parameters for machining the PCD turning tool are set, and the laser output pulse time is modulated. Based on the laser parameters and the structural and surface microtexture parameters of the PCD turning tool, the PCD turning tool is placed on a nanosecond laser micromachining device. For example, the nanosecond laser micromachining device has an XYZ three-axis moving platform capable of XYZ three-axis linkage, with the PCD turning tool placed on the Z-axis platform. For example, the nanosecond laser micromachining device features a common optical path design for image imaging and laser objective lens processing, and the laser processing objective lens undergoes chromatic aberration correction in the visible and near-infrared bands. After processing, the PCD turning tool is ultrasonically cleaned for 30 minutes. After the diluent and solid lubricant are mixed and diluted to form a mixed slurry, it is applied to the surface of the PCD turning tool and then subjected to vacuum negative pressure infiltration and high temperature curing. For example, the diluent and MoS2 are mixed in a ratio of 1:10. In the early stage of cutting, the mixed slurry in the microtexture contacts the workpiece material and forms a transfer film. During the cutting process, the variable cross-section structure slowly releases the lubricant, continuously replenishing the worn lubricating film. Under the condition of no external cutting fluid, the composite material delamination / tearing is avoided, which is environmentally friendly and reduces costs.
[0021] After the PCD turning tool has cooled down, remove the residual slurry from the surface of the PCD turning tool. For example, the cooling time is 2 hours.
[0022] In some embodiments, the structural parameters of the PCD turning tool include: tool tip radius and tool tip angle, for example, a tool tip angle of 80 degrees and a tool tip radius of 0.2 mm; the surface microtexture parameters include: the distance between the surface microtexture and the main cutting edge, the distance between the surface microtexture and the secondary cutting edge, and the distance within the surface microtexture, for example, such as... Figure 2 As shown, the minimum distance between the boundary of the surface microtexture and the main cutting edge is l1 = 100 μm, and the minimum distance between the boundary and the secondary cutting edge is l3 = 100 μm. Along the direction of the main cutting edge, the spacing between the two textures in the surface microtexture is l4 = 50 μm, and along the direction of the secondary cutting edge, the spacing between the two textures in the surface microtexture is l2 = 100 μm. By balancing the lubrication coverage area and the strength of the tool matrix, stress concentration caused by excessive microtexture is prevented. The two lengths of the surface microtexture plane machining are both 1500 μm. The surface microtexture lubrication source is arranged near the cutting heat concentration area to reduce the tool-chip interface temperature in time. At the same time, it avoids weakening the cutting edge strength by being too close.
[0023] In some embodiments, the laser parameters of the PCD turning tool include: laser power, laser frequency, number of processing operations, and processing time. For example, in this processing, the laser wavelength is 1064nm, the laser power is 20W, the laser frequency is 90kHz, and the processing is repeated 20 times. By optimizing the combination of parameters, the processing efficiency can be improved while ensuring quality.
[0024] In some embodiments, the processing of the PCD turning tool includes: automatically focusing the PCD turning tool surface image based on the hill-climbing method to quickly converge to the optimal focal plane, improving processing preparation efficiency; using a gradient sum sharpness operator to calculate sharpness, ensuring that the laser focus is precisely aligned with the PCD turning tool surface, making it more sensitive to the surface texture features of the PCD turning tool and achieving higher focusing accuracy; after focusing, adjusting the laser defocus to prepare the surface microtexture, with a laser defocusing amount of ±0.6μm. By controlling the defocusing amount to increase the spot diameter, a microtexture with the required opening size can be formed in one processing step, improving efficiency and better controlling the opening size and depth of the microtexture. By focusing first and then defocusing, the laser processing defocusing amount is precisely adjusted. During positive defocusing, the laser energy gradually decreases from top to bottom, resulting in a larger area affected by heat before the laser interacts with the PCD surface, leading to an increase in the upper opening diameter W1. During negative defocusing, the laser energy gradually increases from top to bottom, with the maximum laser energy density located below the PCD surface. This results in a smaller area affected by heat before the laser interacts with the PCD surface, leading to a smaller upper opening diameter W1 and an enhanced keyhole effect within the texture, increasing the texture depth H. The laser action on the PCD material generates a large amount of gas and plasma, which creates recoil pressure and causes plasma explosions within the holes, resulting in a change in the waist diameter W2. By controlling the deposition of molten material within the texture using different laser powers and frequencies, the bottom diameter W3 is altered. Therefore, by precisely adjusting the laser defocusing amount, the formation of the bottle-shaped cross-section of the texture can be controlled.
[0025] In some embodiments, machining the PCD turning tool includes machining the PCD turning tool structure according to a delay time set between laser pulse outputs and the number of machining operations.
[0026] In some embodiments, such as Figure 3As shown, the delay time between laser pulse outputs is 1~100μs, with microsecond-level control matching nanosecond / picosecond lasers to achieve a "cold processing" effect and a minimal heat-affected zone. The delay time between processing cycles is set to 100μs~1ms, with millisecond-level inter-point cooling ensuring sufficient heat dissipation and preventing heat accumulation during texture array processing. By setting the T1 timing control within 100μs, a molten pool forms on the PCD surface under laser plasma action and dissipates heat rapidly, preventing the expansion of the heat-affected zone. By the time the next sequence of pulses is applied, the molten pool has already cooled, which helps avoid heat accumulation caused by the laser pulses, thus precisely controlling the texture morphology. By setting the T2 timing control within 100μs~1ms, the heat accumulation from multiple laser processing cycles is effectively reduced, suppressing graphitization and cracking of the PCD matrix, reducing molten pool spatter, and thus achieving precise processing of bottle-shaped cross-section textures. For example, the laser pulse modulation time is 300μs, and the delay time T1 between laser pulse outputs is set to 10μs to control single-point heat accumulation and avoid graphitization of PCD turning tools; the delay time T2 between machining cycles is set to 100μs. By controlling the delay time between laser pulse outputs and the delay time between machining cycles, heat input can be precisely controlled, the overall heat input can be reduced, the tool matrix performance can be protected, and thermal damage to PCD turning tools can be avoided.
[0027] In some embodiments, such as Figure 4 and Figure 5 As shown, the surface microtexture is a pitted structure, with the waist diameter being 0.5 to 0.8 times the diameter of the upper opening and the bottom diameter being 0.8 to 1.2 times the diameter of the upper opening. The narrow waist forms a "liquid-locking" structure to prevent the mixed slurry from flowing out rapidly under centrifugal force, while the wider bottom provides liquid storage space. The waist controls the release rate, the larger upper opening facilitates processing and filling, and the bottom is more firmly integrated with the tool body.
[0028] In some embodiments, the thickness of the mixed slurry scraped onto the surface of the PCD turning tool is 50~100μm. For example, the scraping thickness is 80μm. Compared with spraying / dipping, scraping can achieve more precise thickness control and is beneficial for slurry accumulation at the microtexture openings.
[0029] In some embodiments, the pressure of the vacuum negative pressure osmosis is 10. -1 ~10 -2 Pa, for example, the negative pressure is set to 10. -2 Pa, the high vacuum environment promotes the penetration of the mixed slurry into the depths of the microtexture and eliminates air.
[0030] In some embodiments, the high-temperature curing temperature is 200~300 degrees Celsius, and the holding time is 1~2 hours. For example, the heating time is 1 hour and the heating temperature is 200 degrees Celsius, so that the mixed slurry adheres stably and is below the PCD turning tool degradation temperature.
[0031] The residual MoS2 slurry on the surface of the PCD turning tool is wiped away. The PCD turning tool with the MoS2 coating after fabrication is shown in Figure 6. Figure 6(a) is a PCD turning tool filled with MoS2 solid lubricant, Figure 6(b) is a local micro-pit texture on the tool surface filled with MoS2 solid lubricant, Figure 6(c) is the morphology of a single micro-pit filled with MoS2 solid lubricant, Figure 6(d) is the EDS distribution diagram of S element in Figure 6(c), and Figure 6(e) is the EDS distribution diagram of Mo element in Figure 6(c).
[0032] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to in the method section. This embodiment only describes an electromagnetic field structure designed using a Helmholtz coil and DC high voltage; other methods that utilize electromagnetic fields to confine plasma in a discharge region are within the scope of protection of this patent.
[0033] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A method for manufacturing a composite dry cutting self-lubricating PCD turning tool, characterized in that, include: Set the structural parameters and surface microtexture parameters of the PCD turning tool, wherein the cross-section of the surface microtexture morphology is a variable cross-section; set the laser parameters for machining the PCD turning tool, and modulate the duration of the laser output pulse; The PCD turning tool is machined according to the laser parameters and the structural parameters and surface microtexture parameters of the PCD turning tool; After the diluent and solid lubricant are mixed and diluted to form a slurry, it is applied to the surface of the PCD turning tool and then subjected to vacuum negative pressure penetration and high temperature curing. After the PCD turning tool has cooled down, remove the residual slurry from the surface of the PCD turning tool.
2. The method according to claim 1, characterized in that, The structural parameters of the PCD turning tool include: tool tip radius and tool tip angle; the surface microtexture parameters include: the distance between the surface microtexture and the main cutting edge, the distance between the surface microtexture and the secondary cutting edge, and the distance within the surface microtexture.
3. The method according to claim 1, characterized in that, The laser parameters of the PCD turning tool include: laser power, laser frequency, number of processing operations, and processing time.
4. The method according to claim 1, characterized in that, The process of machining the PCD turning tool includes: automatically focusing the PCD turning tool surface image based on the hill-climbing method; calculating the sharpness using the gradient sum sharpness operator; and after focusing, adjusting the laser defocus to prepare the surface microtexture.
5. The method according to claim 1, characterized in that, The machining of the PCD turning tool includes machining the PCD turning tool structure according to the delay time set between laser pulse outputs and the number of machining operations.
6. The method according to claim 5, characterized in that, The delay time between laser pulse outputs is 1~100μs, and the delay time between processing cycles is set to 100μs~1ms.
7. The method according to claim 1, characterized in that, The surface microtexture is a pitted structure, with the waist diameter being 0.5 to 0.8 times the upper opening diameter and the bottom diameter being 0.8 to 1.2 times the upper opening diameter.
8. The method according to claim 1, characterized in that, The thickness of the mixed slurry scraped onto the surface of the PCD turning tool is 50~100μm.
9. The method according to claim 1, characterized in that, The pressure of the vacuum negative pressure osmosis is 10. -1 ~10 -2 Pa.
10. The method according to claim 1, characterized in that, The high-temperature curing temperature is 200~300 degrees Celsius, and the holding time is 1~2 hours.