A method for enhancing the interfacial bonding strength of a lubricated component based on multi-material light-cured 3D printing

Abstract

This invention discloses a method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing, belonging to the field of additive manufacturing technology. This method introduces interfacial interlocking structures at the interfaces of different materials and employs a variable-parameter printing strategy in the interfacial region to locally control the printing layer thickness and light energy input, achieving refined shaping and dense curing of the interfacial region. Results show that this method can significantly improve the interfacial bonding strength of multi-material components, shifting the fracture location from the interface to the interior of the material, while simultaneously considering printing efficiency and the overall mechanical properties of the component. It is suitable for manufacturing high-performance engineering components with localized self-lubricating requirements.

Description

Technical Field

[0001] This invention belongs to the field of additive manufacturing technology, specifically relating to a method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing. Background Technology

[0002] Polyimide materials are widely used in aerospace, rail transportation, and high-end equipment manufacturing due to their excellent high-temperature resistance, mechanical properties, and chemical corrosion resistance. To meet the requirements of friction reduction, wear resistance, and long service life of components in complex service environments, solid lubricant fillers such as polytetrafluoroethylene are usually introduced into the polyimide matrix to prepare polyimide-based self-lubricating composite materials. With the development of Digital Light Processing (DLP) 3D printing technology, its high forming accuracy and excellent surface quality have made it an important means of preparing complex polymer components. Multi-material DLP 3D printing technology provides new possibilities for realizing the functional integration of components, especially by introducing self-lubricating composite materials only in specific areas of the same component while maintaining high-strength matrix materials in the remaining areas, thereby achieving on-demand lubrication design and avoiding overall material performance degradation.

[0003] However, in the practical application of multi-material DLP 3D printing for on-demand lubrication components, insufficient interfacial bonding strength between different materials has become one of the key issues restricting the engineering application of such components. Although polyimide materials and polyimide-based self-lubricating composites have the same matrix composition, the introduction of solid lubricating fillers in the self-lubricating composites significantly alters the photocuring behavior, rheological properties, and microstructure after curing, making it difficult for the two materials to form an ideal continuous cross-linked network structure at the interface. However, in existing multi-material DLP printing processes, different materials are usually spliced ​​together using uniform printing parameters. This approach easily leads to uneven light energy distribution, mismatched curing depth, and insufficient interlayer bonding at the interface, resulting in obvious mechanically weak areas at the interface. When the component is in service under external loads, stress tends to concentrate at the interface, triggering microcrack initiation and propagation along the interface, ultimately leading to interface delamination or overall component failure. Furthermore, existing technologies for addressing the interfacial bonding problem in multi-materials mainly focus on material formulation optimization or post-processing strengthening methods, such as adjusting filler content, introducing interfacial coupling agents, or using heat treatment to improve interfacial properties. However, the above methods often have problems such as complex processes, limited applicability, or difficulty in deeply integrating with multi-material DLP printing processes, making it difficult to meet the integrated forming requirements of complex structure on-demand lubrication components.

[0004] Therefore, there is an urgent need for a method that can collaboratively improve the interface bonding strength of on-demand lubrication components at the material splicing interface from the perspectives of structural design and forming process during the multi-material digital light processing 3D printing process, so as to achieve high reliability and high performance of multi-material lubrication components. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method for precisely enhancing the interfacial bonding strength of lubrication components based on multi-material photopolymerization 3D printing, so as to solve the problem of low interfacial bonding strength and easy interfacial failure between the matrix material and the self-lubricating composite material in polyimide-based on-demand lubrication components.

[0006] To achieve the above objectives, the present invention employs the following technical solution: This invention discloses a method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing, comprising: Based on the functional requirements of the components, on-demand lubrication design is carried out, and the components are divided into lubrication areas and non-lubrication areas. The lubrication areas are made of polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, and the non-lubrication areas are made of polyimide as the matrix material. Based on a multi-material digital light processing 3D printing device, the lubricated and non-lubricated area models are sliced ​​separately, and an interface enhancement area is constructed at the splicing interface of the two materials. Within the interface enhancement area, an interface interlocking structure is used in the geometric design to increase the interface splicing area and the degree of structural interlocking. A variable parameter printing strategy is adopted for forming. By adjusting the printing layer thickness and / or exposure parameters, the forming parameters of the interface area are different from the main forming parameters of the lubricated and non-lubricated areas (first forming parameters). The lubricated and non-lubricated areas far from the interface adopt the conventional process parameters corresponding to their respective materials (second forming parameters). The integrated digital light processing 3D printing of multi-material components is completed, thereby obtaining on-demand lubricated multi-material components with enhanced interface bonding strength.

[0007] Preferably, the interface interlocking structure is a three-dimensional mechanical interlocking structure constructed at the splicing interface between the lubricated area and the non-lubricated area, and the interlocking structure includes a tenon structure, a sawtooth structure, a corrugated structure, a stepped structure, or a combination thereof.

[0008] More preferably, the interface interlocking structure is periodically distributed along the thickness direction and / or planar direction of the component to form continuous or discrete interlocking units in the interface region.

[0009] More preferably, the interface variable parameter printing strategy includes: The first forming parameter is used for printing in the interface enhancement area, and the second forming parameter is used for printing in the lubrication area and non-lubrication area of ​​the main body away from the interface. Since the optimal forming parameters corresponding to the self-lubricating composite material and the matrix material are different, the first forming parameter and the second forming parameter are both divided into the first self-lubricating composite material parameter, the first matrix material parameter, the second self-lubricating composite material parameter, and the second matrix material parameter.

[0010] More preferably, the printing layer thickness corresponding to the first forming parameter is less than the printing layer thickness corresponding to the second forming parameter, so as to improve the forming accuracy and light energy density of the interface area.

[0011] More preferably, the number of layers of the first self-lubricating composite material parameters and the first matrix material parameters included in the interface enhancement region is the same, which is 3 to 10 layers. The number of layers of the second self-lubricating composite material parameters and the second matrix material parameters is calculated based on the corresponding region model size and layer thickness.

[0012] More preferably, the printing layer thickness of the first self-lubricating composite material parameters and the first matrix material parameters contained in the interface enhancement region is 20-30 μm, and the printing layer thickness of the second self-lubricating composite material parameters and the second matrix material parameters contained in the remaining regions is 40-60 μm.

[0013] More preferably, the interface variable parameter printing strategy further includes adjusting at least one of the exposure time, exposure intensity, or number of scans of the interface area to synergistically improve the consistency of the interface curing depth.

[0014] More preferably, the multi-material digital light processing 3D printing process is a zone-switching printing process, and the parameters of different zones are adjusted synchronously during the zone switching process.

[0015] More preferably, the method is applicable to the manufacture of high-performance engineering components, friction pair components, or wear-resistant components with local self-lubrication requirements.

[0016] Compared with the prior art, the present invention has the following beneficial effects: First, this invention introduces an interlocking structure at the interface of different materials, transforming the interface from a traditional two-dimensional planar joint into a spatial joint structure with three-dimensional mechanical interlocking. This interlocking structure significantly increases the effective joint area of ​​the interface and constructs multi-directional stress transmission paths at both macroscopic and mesoscopic scales, enabling the interface to more effectively disperse loads during stress, reduce stress concentration, and improve the load-bearing capacity and anti-peeling ability of the interface from a structural perspective.

[0017] Secondly, this invention introduces a variable-parameter printing strategy at the interface region. By reducing the printing layer thickness, the local light energy input is controlled. The smaller layer thickness facilitates the uniform distribution of light energy in the interface region, enabling the two materials to form a cross-linked network with consistent curing depth and a dense structure at the interface. Therefore, the interface region achieves higher light energy density and forming accuracy than the main body region. Thus, this invention improves the interlayer bonding quality in the interface region from a process perspective.

[0018] Furthermore, the interlocking structure and the variable-parameter printing strategy work synergistically in the interface region. On one hand, the interlocking structure provides stable geometric constraints for the interface; on the other hand, variable-parameter printing ensures that the interlocking structure and its adjacent areas are fully cured and precisely shaped, thus preventing the interlocking structure from becoming a new source of defects due to insufficient curing. This synergistic effect transforms the interface region from a traditionally weak mechanical area into a region with enhanced mechanical properties.

[0019] Experimental results show that, in tensile and other mechanical tests, the fracture locations of multi-material components prepared using the method of this invention are no longer concentrated at the material splicing interface, but are more evenly distributed within the material, indicating that the interfacial bonding strength has reached or is close to the strength level of the material bulk. This result verifies the effectiveness of the interface synergistic enhancement mechanism from a macroscopic mechanical behavior perspective. In summary, this invention provides a new approach to interface strengthening that deeply integrates structural design and forming process for multi-material digital light processing 3D printed on-demand lubrication components, demonstrating significant technological advancement and application promotion value.

[0020] Preferably, the present invention significantly improves the interface bonding strength while taking into account the overall printing efficiency by using refined printing parameters only locally near the interface and high-efficiency forming parameters with larger layer thickness in other areas. This avoids a significant increase in forming time caused by global parameter optimization and has good engineering applicability. Attached Figure Description

[0021] Figure 1 A process flowchart for the method of enhancing interfacial bonding strength of multi-material digital light processing 3D printing on-demand lubrication components provided by the present invention; Figure 2 This is a process flow diagram of a method for enhancing the interfacial bonding strength of a multi-material digital light processing 3D printing on-demand lubrication component provided by a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the interface of a multi-material digital light processing 3D printed on-demand lubrication component in an embodiment of the present invention; Figure 4 This is a schematic diagram of the interlocking structure of the multi-material parts interface in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the interlocking structure of the multi-material parts interface in Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of the interlocking structure of the multi-material parts interface in Embodiment 3 of the present invention; In the diagram, A represents the lubricated area, and B represents the non-lubricated area. Figure 7 These are the tensile stress-strain curves of the tensile specimens in the embodiments and comparative examples of this invention. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 A method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing, comprising: S1: Based on the lubrication scheme of the on-demand lubrication component, it is divided into a lubrication area and a non-lubrication area, which respectively use self-lubricating composite materials and matrix materials; S2: Slice the different regions of the model separately, and construct an interface enhancement region at the splicing interface of the two materials; S3: In the interface enhancement area, an interface interlocking structure is used for geometric design; S4: A variable parameter printing strategy is used to form the interface enhancement area (first forming parameter), while the lubricated and non-lubricated areas far from the interface use the conventional process parameters corresponding to each material (second forming parameter); S5: Complete the integrated digital light processing 3D printing of multi-material components to obtain on-demand lubricated multi-material components with enhanced interface bonding strength.

[0025] Specifically, see Figure 2 The present invention provides a method for enhancing interfacial bonding strength of on-demand lubrication components based on multi-material digital light processing 3D printing, comprising the following steps: 1) Lubrication design is carried out on demand according to the functional requirements of the components. The components are divided into lubrication areas and non-lubrication areas. The lubrication area uses polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, while the non-lubrication area uses polyimide as the matrix material.

[0026] 2) Based on a multi-material digital light processing 3D printing device, the lubricated and non-lubricated areas of the model are sliced ​​separately, and an interface reinforcement region is constructed at the interface between the two materials. Within the interface reinforcement region, an interface interlocking structure is used for geometric design to increase the interface splicing area and the degree of structural interlocking. The interlocking structure includes mortise and tenon structures, sawtooth structures, corrugated structures, stepped structures, or combinations thereof. The interface interlocking structure is periodically distributed along the thickness direction and / or planar direction of the component to form continuous or discrete interlocking units in the interface region.

[0027] 3) Within the interface enhancement region, a variable-parameter printing strategy is employed. By adjusting the printing layer thickness and / or exposure parameters, the forming parameters of the interface region differ from the main forming parameters (first forming parameters) of the lubricated and non-lubricated regions. The lubricated and non-lubricated regions, located far from the interface, utilize their respective material's conventional process parameters (second forming parameters). See also Figure 3 Since the optimal forming parameters for the self-lubricating composite material and the matrix material are different, both the first and second forming parameters are divided into first self-lubricating composite material parameters, first matrix material parameters, second self-lubricating composite material parameters, and second matrix material parameters. The printing layer thickness corresponding to the first forming parameter is smaller than that corresponding to the second forming parameter to improve the forming accuracy and light energy density of the interface region. The interface reinforcement region contains the same number of layers for the first self-lubricating composite material parameters and the first matrix material parameters, ranging from 3 to 10 layers, with a printing layer thickness of 20 to 30 μm. The printing layer thickness for the second self-lubricating composite material parameters and the second matrix material parameters is 40 to 60 μm, and the number of layers is calculated based on the corresponding region model size and layer thickness. The interface variable parameter printing strategy also includes adjusting at least one of the exposure time, exposure intensity, or number of scans in the interface region to synergistically improve the consistency of the interface curing depth.

[0028] 4) Using the model and material printing parameters determined in step 3), import them into a multi-material digital light processing 3D printer for zone-switching printing, and adjust the parameters synchronously for different zones during the zone switching process. This completes the integrated digital light processing 3D printing of multi-material components.

[0029] 5) After printing, perform appropriate post-processing and cleaning on the parts, such as removing the support structure, cleaning the surface, secondary curing, heat treatment, etc., to ensure the surface smoothness and integrity of the parts, and finally obtain on-demand lubricated multi-material components with enhanced interface bonding strength.

[0030] The present invention will be further described in detail below with reference to specific embodiments: Example 1 A method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing includes the following steps: 1) Lubrication design is carried out on demand according to the functional requirements of the components. The components are divided into lubrication areas and non-lubrication areas. The lubrication area uses polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, while the non-lubrication area uses polyimide as the matrix material.

[0031] 2) Based on a multi-material digital light processing 3D printing device, the lubricated and non-lubricated areas of the model are sliced ​​separately, and an interface reinforcement region is constructed at the interface between the two materials. Within the interface reinforcement region, an interlocking interface structure is used for geometric design to increase the interface splicing area and the degree of structural interlocking. See [link to documentation]. Figure 4 In this embodiment, the interlocking structure adopts a sawtooth structure, and the interface interlocking structure is periodically distributed along the thickness direction and / or planar direction of the component to form continuous or discrete interlocking units in the interface region.

[0032] 3) Within the interface enhancement region, a variable-parameter printing strategy is employed for forming. By adjusting the printing layer thickness and / or exposure parameters, the forming parameters of the interface region differ from the main forming parameters (first forming parameters) of the lubricated and non-lubricated regions. The lubricated and non-lubricated regions, far from the interface, use their respective material's conventional process parameters (second forming parameters). Since the optimal forming parameters for the self-lubricating composite material and the matrix material differ, both the first and second forming parameters are divided into first self-lubricating composite material parameters, first matrix material parameters, second self-lubricating composite material parameters, and second matrix material parameters. The printing layer thickness corresponding to the first forming parameter is less than that corresponding to the second forming parameter to improve the forming accuracy and light energy density of the interface region. Specifically, in this embodiment, the interface enhancement region contains the same number of layers for both the first self-lubricating composite material parameters and the first matrix material parameters, which are 4 layers each, with a printing layer thickness of 25 μm. The printing layer thickness for both the second self-lubricating composite material parameters and the second matrix material parameters is 50 μm, and the number of layers is calculated based on the corresponding region model size and layer thickness, resulting in 38 layers for both. The printing time for the parameters of the first self-lubricating composite material is 6 seconds, the printing time for the parameters of the first matrix material is 8 seconds, the printing time for the parameters of the second self-lubricating composite material is 15 seconds, and the printing time for the parameters of the second matrix material to finally obtain the on-demand lubrication multi-material component is 10 seconds.

[0033] 4) Using the model and material printing parameters determined in step 3), import them into a multi-material digital light processing 3D printer for zone switching printing. During the zone switching process, adjust the synchronous parameters of different zones to complete the integrated digital light processing 3D printing of multi-material components.

[0034] 5) After printing, perform appropriate post-processing and cleaning on the parts, such as removing the support structure, cleaning the surface, secondary curing, heat treatment, etc., to ensure the surface smoothness and integrity of the parts, and finally obtain on-demand lubricated multi-material components with enhanced interface bonding strength.

[0035] Example 2 A method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing includes the following steps: 1) Lubrication design is carried out on demand according to the functional requirements of the components, and the components are divided into lubrication areas and non-lubrication areas. The lubrication areas are made of polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, and the non-lubrication areas are made of polyimide as the matrix material.

[0036] 2) Using a multi-material digital light processing 3D printing device, the lubricated and non-lubricated areas of the model are sliced ​​separately, and an interface reinforcement region is constructed at the interface between the two materials. Within the interface reinforcement region, an interface interlocking structure is used for geometric design to increase the interface splicing area and the degree of structural interlocking. See [link to documentation]. Figure 5 In this embodiment, the interlocking structure is designed as a corrugated structure. The interface interlocking structure is periodically distributed along the plane of the component to form continuous or discrete interlocking units in the interface region.

[0037] 3) Within the interface enhancement region, a variable-parameter printing strategy is employed for forming. By adjusting the printing layer thickness and / or exposure parameters, the forming parameters of the interface region differ from the main forming parameters (first forming parameters) of the lubricated and non-lubricated regions. The lubricated and non-lubricated regions, far from the interface, use their respective material's conventional process parameters (second forming parameters). Since the optimal forming parameters for the self-lubricating composite material and the matrix material differ, both the first and second forming parameters are divided into first self-lubricating composite material parameters, first matrix material parameters, second self-lubricating composite material parameters, and second matrix material parameters. The printing layer thickness corresponding to the first forming parameter is less than that corresponding to the second forming parameter to improve the forming accuracy and light energy density of the interface region. Specifically, in this embodiment, the interface enhancement region includes the same number of layers for both the first self-lubricating composite material parameters and the first matrix material parameters, which are 4 layers each, with a printing layer thickness of 25 μm. The printing layer thickness for both the second self-lubricating composite material parameters and the second matrix material parameters is 50 μm, and the number of layers is calculated based on the corresponding region model size and layer thickness, resulting in 38 layers for both. The printing time for the parameters of the first self-lubricating composite material is 6 seconds, the printing time for the parameters of the first matrix material is 8 seconds, the printing time for the parameters of the second self-lubricating composite material is 15 seconds, and the printing time for the parameters of the second matrix material is 10 seconds.

[0038] 4) Using the model and material printing parameters determined in step 3), import them into a multi-material digital light processing 3D printer for zone-switching printing, and adjust the parameters synchronously for different zones during the zone switching process. This completes the integrated digital light processing 3D printing of multi-material components.

[0039] 5) After printing, perform appropriate post-processing and cleaning on the parts, such as removing the support structure, cleaning the surface, secondary curing, heat treatment, etc., to ensure the surface smoothness and integrity of the parts, and finally obtain on-demand lubricated multi-material components with enhanced interface bonding strength.

[0040] Example 3 A method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing includes the following steps: 1) Lubrication design is carried out on demand according to the functional requirements of the components, and the components are divided into lubrication areas and non-lubrication areas. The lubrication areas are made of polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, and the non-lubrication areas are made of polyimide as the matrix material.

[0041] 2) Using a multi-material digital light processing 3D printing device, the lubricated and non-lubricated areas of the model are sliced ​​separately, and an interface reinforcement region is constructed at the interface between the two materials. Within the interface reinforcement region, an interface interlocking structure is used for geometric design to increase the interface splicing area and the degree of structural interlocking. See [link to documentation]. Figure 6 In this embodiment, the interlocking structure is designed as an L-shaped tenon and mortise structure. The interface interlocking structure is periodically distributed along the plane of the component to form continuous or discrete interlocking units in the interface region.

[0042] 3) Within the interface enhancement region, a variable-parameter printing strategy is employed for forming. By adjusting the printing layer thickness and / or exposure parameters, the forming parameters of the interface region differ from the main forming parameters (first forming parameters) of the lubricated and non-lubricated regions. The lubricated and non-lubricated regions, far from the interface, use their respective material's conventional process parameters (second forming parameters). Since the optimal forming parameters for the self-lubricating composite material and the matrix material differ, both the first and second forming parameters are divided into first self-lubricating composite material parameters, first matrix material parameters, second self-lubricating composite material parameters, and second matrix material parameters. The printing layer thickness corresponding to the first forming parameter is less than that corresponding to the second forming parameter to improve the forming accuracy and light energy density of the interface region. Specifically, in this embodiment, the interface enhancement region includes the same number of layers for both the first self-lubricating composite material parameters and the first matrix material parameters, which are 4 layers each, with a printing layer thickness of 25 μm. The printing layer thickness for both the second self-lubricating composite material parameters and the second matrix material parameters is 50 μm, and the number of layers is calculated based on the corresponding region model size and layer thickness, resulting in 38 layers for both. The printing time for the parameters of the first self-lubricating composite material is 6 seconds, the printing time for the parameters of the first matrix material is 8 seconds, the printing time for the parameters of the second self-lubricating composite material is 15 seconds, and the printing time for the parameters of the second matrix material is 10 seconds.

[0043] 4) Using the model and material printing parameters determined in step 3), import them into a multi-material digital light processing 3D printer for zone-switching printing, and adjust the parameters synchronously for different zones during the zone switching process. This completes the integrated digital light processing 3D printing of multi-material components.

[0044] 5) After printing, perform appropriate post-processing and cleaning on the parts, such as removing the support structure, cleaning the surface, secondary curing, heat treatment, etc., to ensure the surface smoothness and integrity of the parts, and finally obtain on-demand lubricated multi-material components with enhanced interface bonding strength.

[0045] Comparative Example A method for on-demand lubrication components produced by multi-material digital light processing 3D printing with direct interface splicing includes the following steps: 1) Lubrication design is carried out on demand according to the functional requirements of the components, and the components are divided into lubrication areas and non-lubrication areas. The lubrication areas are made of polytetrafluoroethylene-reinforced polyimide self-lubricating composite material, and the non-lubrication areas are made of polyimide as the matrix material.

[0046] 2) Using a multi-material digital light processing 3D printing device, slice the lubricated and non-lubricated area models respectively.

[0047] 3) The lubricated and non-lubricated regions used their respective forming parameters for the self-lubricating composite material and the matrix material, respectively. The printing layer thickness for both the lubricated and non-lubricated regions was 50 μm, and the number of layers was 40. The printing time for the self-lubricating composite material parameters was 15 s, and the printing time for the matrix material parameters was 10 s.

[0048] 4) Using the model and material printing parameters determined in step 3), import them into a multi-material digital light processing 3D printer for partitioned switching printing, and complete the integrated digital light processing 3D printing of multi-material components.

[0049] 5) After printing, perform appropriate post-processing and cleaning on the parts, such as removing the support structure, cleaning the surface, secondary curing, heat treatment, etc., to ensure the surface smoothness and integrity of the parts, and finally obtain multi-material components that can be lubricated as needed.

[0050] The parts obtained from the above embodiments and comparative examples were subjected to tensile property tests according to GB / T 1040.2-2022. The tensile curves are shown in [reference needed]. Figure 7 The test results are shown in Table 1: Table 1. Tensile property test results of the prototype and comparative specimens.

[0051] As shown in Table 1, the tensile strength of polyimide and its self-lubricating composite parts prepared by multi-material digital light processing 3D printing after the interface bonding strength is increased is much higher than that of parts directly formed by multi-material digital light processing 3D printing of polyimide and its self-lubricating composite parts. This significantly improves the mechanical properties of multi-material on-demand lubrication components, enhancing their service performance while ensuring precise on-demand lubrication. They can be used in the manufacture of lubrication components in high-end equipment fields such as aerospace and robotics, and have broad application prospects.

[0052] In summary, this invention addresses the problem of insufficient interfacial bonding strength between polyimide materials and polyimide-based self-lubricating composites in multi-material digital light processing 3D printing, proposing an interface synergistic enhancement mechanism. By introducing interfacial interlocking structures at the interfaces of different materials and employing a variable-parameter printing strategy in the interfacial region, the printing layer thickness and light energy input are locally controlled, achieving refined shaping and dense curing of the interfacial region. Results show that this method can significantly improve the interfacial bonding strength of multi-material components, shifting the fracture location from the interface to the interior of the material, while simultaneously considering printing efficiency and the overall mechanical properties of the component. This method is suitable for manufacturing high-performance engineering components with localized self-lubrication requirements.

[0053] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing, characterized in that, Includes the following steps: 1) Based on the lubrication scheme of the on-demand lubrication component, the component is divided into a lubrication area and a non-lubrication area; wherein, the lubrication area adopts a self-lubricating composite material, and the non-lubrication area adopts a matrix material that is compatible with the self-lubricating composite material; 2) The three-dimensional models of the lubricated and non-lubricated areas are sliced ​​using a multi-material digital light processing 3D printing method, and an interface enhancement area is constructed at the splicing interface of the two materials. 3) Design an interface interlocking structure within the interface enhancement area; 4) A variable parameter printing strategy is used to form the material in the interface enhancement area, while the conventional printing process parameters corresponding to the respective materials are used in the lubrication and non-lubrication areas far away from the interface. 5) Execute the multi-material photopolymerization 3D printing process to obtain on-demand lubricated multi-material components with enhanced interface bonding strength after printing.

2. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 1, characterized in that, In step 1), the self-lubricating composite material used in the lubricated area is polytetrafluoroethylene-reinforced polyimide; the matrix material used in the non-lubricated area is polyimide.

3. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 1, characterized in that, In step 3), the interlocking structure is periodically distributed along the thickness direction and / or planar direction of the component to form continuous or discrete interlocking units in the interface region.

4. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 3, characterized in that, The interlocking structure includes one or more of the following: mortise and tenon structure, sawtooth structure, corrugated structure, and stepped structure.

5. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 1, characterized in that, In step 4), the interface variable parameter printing strategy includes: The first forming parameter is used for printing within the interface enhancement area, while the second forming parameter is used for printing the main body portion in the lubricated and non-lubricated areas far from the interface; wherein: The first forming parameters include first self-lubricating composite material parameters and first matrix material parameters; The second forming parameters include the second self-lubricating composite material parameters and the second matrix material parameters.

6. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 5, characterized in that, Printing is performed in the interface enhancement area using the parameters of the first self-lubricating composite material combined with the parameters of the first matrix material. Printing is performed using the parameters of a second self-lubricating composite material within the lubrication zone; Printing is performed using a second matrix material parameter in non-lubricated areas.

7. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 6, characterized in that, The printing layer thickness of the first self-lubricating composite material parameters and the first matrix material parameters contained in the interface enhancement region is 20-30 μm, and the printing layer thickness of the second self-lubricating composite material parameters contained in the lubrication region and the second matrix material parameters contained in the non-lubrication region is 40-60 μm.

8. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 6, characterized in that, The printing layer thickness corresponding to the first forming parameter is less than the printing layer thickness corresponding to the second forming parameter; the number of layers of the first self-lubricating composite material parameter and the first matrix material parameter included in the interface reinforcement region is the same, which is 3 to 10 layers; the number of layers of the second self-lubricating composite material parameter and the second matrix material parameter is calculated according to the corresponding region model size and layer thickness.

9. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 5, characterized in that, The interface variable parameter printing strategy also includes adjusting at least one of the exposure time, exposure intensity and number of scans of the interface area to synergistically improve the consistency of the interface curing depth.

10. The method for precisely enhancing the interfacial bonding strength of lubricating components based on multi-material photopolymerization 3D printing according to claim 1, characterized in that, In step 5), the integrated photopolymer 3D printing process involves zone switching printing, and the parameters of different zones are adjusted synchronously during the zone switching process.

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