A wide-temperature-range polyether ether ketone-based self-lubricating composite material part for LPBF and a forming method thereof

Abstract

The application discloses a wide-temperature-range polyether ether ketone-based self-lubricating composite material part for LPBF and a forming method thereof, and belongs to the technical field of additive manufacturing, and comprises the following steps: respectively pretreating polyether ether ketone powder and molybdenum disulfide powder in different ways; mechanically mixing the two kinds of powder in a specific ratio after pretreatment to obtain wide-temperature-range polyether ether ketone-based self-lubricating composite material powder; and printing and forming the polyether ether ketone-based self-lubricating composite material powder by adopting a specific laser powder bed fusion (LPBF) process to obtain a wide-temperature-range polyether ether ketone-based self-lubricating composite material part. The application enhances the friction and wear performance of polyether ether ketone in a wide temperature range by using molybdenum disulfide, improves the printability of the powder through special pretreatment, adopts a specific LPBF process forming such as multidirectional cross scanning, and obtains a high-performance wide-temperature-range polyether ether ketone-based self-lubricating composite material part suitable for high and low temperature extreme environments.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of additive manufacturing, and particularly relates to a wide-temperature-range polyether ether ketone-based self-lubricating composite material part for LPBF and a forming method thereof. BACKGROUND

[0002] Polyether ether ketone (PEEK) is a special engineering plastic with excellent performance, and has excellent mechanical strength, high temperature resistance, corrosion resistance and good biocompatibility, and is widely used in high-end manufacturing fields such as aerospace, medical devices, electronics and electrical appliances. With the development of additive manufacturing technology, the use of laser powder bed fusion (LPBF) process to process PEEK materials has gradually attracted the attention of researchers and engineering application fields. LPBF technology can realize high-precision manufacturing of complex structures, has good process adaptability and design flexibility, and provides a new forming method for high-performance application of PEEK materials.

[0003] However, there are still a series of technical difficulties in the LPBF forming process of pure PEEK material. On the one hand, the melting temperature of PEEK material is high, and the requirements for equipment temperature control, laser energy input, powder laying and other parameters are strict, which is easy to cause insufficient melting, forming warping or poor interlayer bonding, etc., which restricts the further improvement of the forming precision and mechanical properties. On the other hand, the tribological properties of PEEK material under wide temperature range are insufficient, and it is easy to cause adhesive wear under high and low temperature extreme conditions (-150℃~150℃), which limits its application in extreme temperature moving parts in space environment and other scenes.

[0004] In order to improve the tribological properties under high and low temperature, some studies try to introduce solid lubricants such as molybdenum disulfide (MoS2) into PEEK matrix, and improve the self-lubricating properties of the material through physical mixing or blending modification. However, in the prior art, the addition of lubricating phase often leads to the decrease of powder flowability, particle agglomeration and the decrease of forming process stability, and this strategy of introducing solid lubricant into PEEK matrix often lacks specific powder material optimization for the process characteristics of LPBF, and it is difficult to realize the double improvement of performance and forming quality from the perspective of material component improvement.

[0005] In addition, the existing technology focuses on the construction of composite formula, and lacks systematic supporting measures for powder pretreatment, mixing uniformity control, LPBF forming process parameter setting and post-processing method, etc., which leads to certain limitations in the size stability, self-lubricating performance and high and low temperature adaptability of the formed parts, and it is difficult to meet the long-term service requirements under wide temperature range and complex working conditions.

[0006] Therefore, it is urgent to provide a wide-temperature-range PEEK-based self-lubricating composite material forming method suitable for the LPBF process to realize the synergistic optimization of the performance of the workpiece, the forming quality and the processing technology. SUMMARY

[0007] In order to overcome the above-mentioned defects of the prior art, the purpose of the present application is to provide a wide-temperature-range PEEK-based self-lubricating composite material workpiece and a forming method for LPBF, so as to solve the problems of insufficient tribological performance and unstable forming of the PEEK material formed by the LPBF process in a wide temperature range.

[0008] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0009] The first purpose of the present application is to provide a forming method for a wide-temperature-range PEEK-based self-lubricating composite material workpiece for LPBF, characterized in that it comprises:

[0010] Taking PEEK powder and MoS2 powder, after pretreatment respectively, mix them uniformly to obtain wide-temperature-range PEEK-based self-lubricating composite material powder;

[0011] Based on the workpiece model, using the wide-temperature-range PEEK-based self-lubricating composite material powder as raw material, printing forming is carried out by LPBF technology, and after cooling, a wide-temperature-range PEEK-based self-lubricating composite material workpiece is obtained.

[0012] Preferably, in the wide-temperature-range PEEK-based self-lubricating composite material powder, the PEEK powder is 85-95 wt%, and the MoS2 powder is 5-15 wt%.

[0013] Preferably, the pretreatment comprises:

[0014] Taking PEEK powder, layer-by-layer high-temperature powder laying treatment is carried out in the LPBF equipment (HT-LPBF 300), the powder laying layer thickness is 0.1 mm, the powder laying speed is 50-100 mm / s, and the width temperature is 300-310℃.

[0015] Taking MoS2 powder, vacuum drying box (DZF-6050) drying treatment is carried out at 150-200℃ for 6-8h.

[0016] Further preferably, the pretreated PEEK powder and MoS2 powder are mechanically mixed by a three-dimensional mixer (SYH-20L), the mechanical mixing speed is 200-300r / min, and the mixing time is 2-3h.

[0017] Further preferably, the particle size of the PEEK powder is 50-100μm, and the particle size of the MoS2 powder is 1-10μm.

[0018] Preferably, in the LPBF printing forming process, the powder supply cylinder width temperature is maintained at 240-280 DEG C, the preheating temperature of the forming cylinder is 320-330 DEG C, and the pre-powder bed thickness is 4-6 mm.

[0019] Preferably, the process parameters for printing forming by using the LPBF technology are: laser power is 15-18 W, scanning speed is 2500-3000 mm / s, layer thickness is 0.1 mm, and scanning spacing is 0.1 mm.

[0020] Preferably, in the printing forming process by using the LPBF technology, the laser scanning adopts a multi-directional cross scanning strategy, that is, scanning twice in each layer, the included angle of the scanning path in the layer is 60-90 DEG, and the included angle of the scanning path between layers is 30-60 DEG.

[0021] Preferably, after the printing forming by using the LPBF technology is completed, the workpiece is subjected to in-cylinder gradient heat treatment, the workpiece is buried in powder for 5-10 mm by continuous powder laying, the width temperature is 300-320 DEG C, the temperature is maintained for 1-2 h, then gradient cooling is carried out, the cooling rate is 10 DEG C / min, and the temperature is maintained for 0.5 h every 30-50 DEG C, until the workpiece is taken out after being cooled to room temperature.

[0022] The second object of the application is to disclose the wide-temperature-range PEEK-based self-lubricating composite material workpiece for LPBF prepared by the above forming method.

[0023] Compared with the prior art, the application has the following beneficial effects:

[0024] The wide-temperature-range PEEK-based self-lubricating composite material workpiece for LPBF and the forming method thereof disclosed by the application have the following advantages: the wide-temperature-range PEEK-based self-lubricating composite material workpiece prepared by the application can exhibit stable lubricating effect and low friction and wear performance in the range from extremely low temperature to high temperature. Compared with the existing self-lubricating materials, MoS2 in the composite material is easy to slip between layers under the action of shear force due to its unique layered crystal structure, and can form a stable lubricating film on the surface of the material. In addition, MoS2 can maintain the stability of the interlayer structure at low temperature, and has good chemical inertness and thermal stability at high temperature, so that the wide-temperature-range PEEK-based self-lubricating composite material has excellent self-lubricating ability in a wide temperature range, and meets the engineering application requirements of long period and no lubricating maintenance under extreme working conditions.

[0025] Further, the powder ratio of the wide-temperature-range PEEK-based self-lubricating composite material of the present application has the following advantages: by adjusting the mass percentage of the PEEK matrix and the MoS2 lubricating phase, the synergy between the self-lubricating performance and the mechanical performance is achieved. This ratio design not only ensures the uniform dispersion of MoS2 in the matrix, avoiding forming defects caused by excessive lubricating phase, but also ensures the continuity of the PEEK structure, so that the material can maintain excellent mechanical strength while obtaining significant friction reduction and wear resistance. Compared with traditional composite materials, this ratio range improves the overall performance stability of the composite system, which is suitable for the manufacturing needs of high-performance mechanical components.

[0026] Further, the PEEK and MoS2 powders are respectively subjected to high-temperature powder laying and drying treatment before mixing, which significantly improves the flowability and forming consistency of the powders. The high-temperature powder laying process of PEEK powder helps to eliminate adsorbed moisture and surface charge effects, avoiding powder agglomeration, while the drying treatment of MoS2 can effectively remove moisture and inhibit gas evolution during the sintering process, thereby reducing forming defects. Through such pretreatment, the present application overcomes the problems of uneven forming and porosity that often occur in multi-component powder systems during additive manufacturing.

[0027] Further, the particle size matching of the selected PEEK and MoS2 powders ensures good melting compatibility and uniform distribution during powder laying and laser melting. The particle size of PEEK powder is beneficial for layer-by-layer spreading, while the small particle size of MoS2 powder facilitates interstitial filling and uniform distribution in the matrix powder, forming lubrication channels. The optimization of particle size ratio effectively reduces the porosity of the powder bed, improves the forming density, and promotes the thermal conductivity stability of the molten pool, thereby enabling the formed part to have excellent structural integrity and functionality.

[0028] Further, by preheating the forming cylinder and the powder supply cylinder, the thermal stability control of the powder bed is achieved, effectively inhibiting thermal deformation and crack defects caused by temperature difference. Compared with traditional forming processes, this temperature control design significantly improves the thermal stability and structural consistency of the composite material during laser selective melting.

[0029] Further, the combination of laser power and scanning speed is optimized to enable the composite powder to obtain a uniform and stable molten pool state during processing, effectively preventing material ablation or insufficient melting. Suitable layer thickness and scanning spacing design further enhances the bonding strength between the melt channels and the overall density. Compared with unoptimized processing parameters, the process combination provided by the present application improves the surface quality and internal structural density of the formed part, significantly reducing the probability of forming defects.

[0030] Further, the multi-directional cross-scan path sets different scan angles in the layer and between layers, effectively breaking the structure anisotropy problem caused by single-direction scanning in the forming process. The staggered path design helps to homogenize the stress distribution in each direction, improving the mechanical stability and use reliability of the composite parts in each principal stress direction. Compared with the single-direction or double-direction scanning mode, this scanning strategy is more suitable for the manufacturing of functional components with high precision requirements.

[0031] Further, the formed parts are buried in powder and subjected to high-temperature holding and gradient cooling treatment, effectively releasing the residual stress accumulated during the manufacturing process, preventing cracking or performance degradation due to thermal stress in the later use. The slow and staged cooling process further ensures the thermal stability of the material structure, improving the dimensional accuracy and long-term service ability of the parts. Compared with the conventional rapid cooling method, this post-processing scheme can more effectively ensure the integrity and functional durability of the composite structure.

[0032] The wide-temperature-range PEEK-based self-lubricating composite part obtained by the preparation and forming method provided by the application can ensure the excellent mechanical properties of PEEK itself and has excellent self-lubricating and tribological properties in a wide temperature range (-150℃ to 150℃). BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The process flow chart of the wide-temperature-range PEEK-based self-lubricating composite material preparation and forming method for LPBF provided by the application is provided.

[0034] Figure 2 The process flow chart of the wide-temperature-range PEEK-based self-lubricating composite material preparation and forming method for LPBF provided by the application is provided.

[0035] Figure 3 The wide-temperature-range friction curve of the friction and wear test piece in the embodiment and the comparative example of the application. DETAILED DESCRIPTION

[0036] In order to enable the personnel in the technical field to better understand the application scheme, the technical solutions in the embodiments of the application will be described clearly and completely below in conjunction with the drawings in the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by the personnel in the field without creative labor should belong to the protection scope of the application.

[0037] It should be noted that the terms "first", "second", and the like in the description and in the claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0038] Referring to Figure 1 The present application provides a forming method of a wide-temperature-range PEEK-based self-lubricating composite part for LPBF, comprising:

[0039] S1: PEEK powder and MoS2 powder are pretreated in different ways respectively;

[0040] S2: The two powders are mechanically mixed in a specific ratio to obtain a wide-temperature-range PEEK-based self-lubricating composite powder;

[0041] S3: The material is printed and formed by using a specific process of LPBF to obtain a wide-temperature-range PEEK-based self-lubricating composite part.

[0042] Referring to Figure 2 The present application provides a forming method of a wide-temperature-range PEEK-based self-lubricating composite part for LPBF, comprising:

[0043] 1) PEEK powder is subjected to layer-by-layer high-temperature powder laying treatment in an LPBF device (HT-LPBF 300), the powder laying layer thickness is 0.1 mm, the powder laying speed is 50-100 mm / s, and the web temperature is 300-310℃, and the PEEK powder is recovered after high-temperature powder laying treatment; before mixing, MoS2 powder is dried in a vacuum drying box (DZF-6050) at 150-200℃ for 6-8h. The particle size of the used PEEK powder is 50-100μm, and the particle size of the used MoS2 powder is 1-10μm.

[0044] 2) In the wide-temperature-range PEEK-based self-lubricating composite powder, PEEK accounts for 85-95% and MoS2 accounts for 5-15% by mass percentage. The PEEK powder and MoS2 powder treated in step 1) are mechanically mixed by using a three-dimensional stirrer (SYH-20L) at a speed of 200-300r / min for 2-3h.

[0045] 3) The preheating temperature of the forming cylinder of the powder bed of the wide-temperature-range PEEK self-lubricating composite material before LPBF forming is 320-330°C, the powder supply cylinder surface temperature is maintained at 240-280°C, and the pre-powder bed thickness is 4-6 mm. The LPBF forming process parameters are: laser power is 15-18 W, scanning speed is 2500-3000 mm / s, layer thickness is 0.1 mm, and scanning spacing is 0.1 mm. The laser scanning strategy during LPBF forming is multi-directional cross scanning, i.e., scanning twice in each layer, the included angle of the two times of scanning in the layer is 60-90°, and the included angle of the scanning path between layers is 30-60°.

[0046] 4) After LPBF printing, gradient heat treatment in the cylinder is performed on the part, the part is buried in powder by continuous powder laying for 5-10 mm, the surface temperature is 300-320°C, and the temperature is maintained for 1-2 h, then gradient cooling is performed at a rate of 10°C / min, and the temperature is maintained for 0.5 h every 30-50°C.

[0047] 5) After step 4) is completed, the powder is removed after being cooled to room temperature, and the wide-temperature-range PEEK-based self-lubricating composite material part is obtained.

[0048] The method of the present application is further described below in conjunction with the drawings and examples. In the following examples, conventional instruments and equipment in the art are used, and various raw materials and reagents used are commercially available unless otherwise specified, and their specifications are conventional specifications in the art, or they can be prepared or prepared according to the instructions of known methods or reagents. The experimental methods not specified in the following examples are usually carried out according to conventional conditions, or according to the conditions recommended by the manufacturer.

[0049] Example

[0050] In this embodiment, the forming method of the wide-temperature-range PEEK-based self-lubricating composite material part for LPBF comprises the following steps:

[0051] 1) PEEK powder is subjected to layer-by-layer high-temperature powder laying treatment in an LPBF device (HT-LPBF 300), the powder laying layer thickness is 0.1 mm, the powder laying speed is 50-100 mm / s, and the surface temperature is 300-310°C, and the PEEK powder after high-temperature powder laying treatment is recovered; before mixing, MoS2 powder is dried in a vacuum drying oven (DZF-6050) at 150-200°C for 6-8 h. The particle size of the PEEK powder used is 50-100 μm, and the particle size of the MoS2 powder used is 1-10 μm.

[0052] 2) The PEEK accounts for 88% and the MoS2 accounts for 12% by mass percentage in the PEEK-based self-lubricating composite material powder with a wide temperature range. The PEEK powder treated in step 1) and the MoS2 powder are mechanically mixed by using a three-dimensional stirrer (SYH-20L) at a rotating speed of 200-300 r / min for 2-3 h.

[0053] 3) The forming cylinder preheating temperature of the powder bed before the LPBF forming of the PEEK-based self-lubricating composite material with a wide temperature range is 320-330 ℃, the powder supply cylinder surface temperature is maintained at 240-280 ℃, and the pre-powder bed thickness is 4-6 mm. The LPBF forming process parameters are as follows: the laser power is 15-18 W, the scanning speed is 2500-3000 mm / s, the layer thickness is 0.1 mm, and the scanning interval is 0.1 mm. The laser scanning strategy in the LPBF forming process is multi-directional cross scanning, that is, scanning twice in each layer, the layer-in angle is 60-90°, and the layer-to-layer scanning path angle is 30-60°.

[0054] 4) After the LPBF printing is completed, the cylinder gradient heat treatment is performed on the workpiece, the workpiece is buried in the powder by 5-10 mm through continuous powder laying, the surface temperature is 300-320 ℃, the temperature is maintained for 1-2 h, then gradient cooling is performed at a rate of 10 ℃ / min, and the temperature is maintained for 0.5 h every 30-50 ℃.

[0055] 5) After the step 4) is completed, the powder is removed after being cooled to room temperature, and the PEEK-based self-lubricating composite material workpiece with a wide temperature range is obtained.

[0056] Comparative Example 1

[0057] The pure PEEK material is formed by using a conventional LPBF process, which includes the following steps:

[0058] 1) The PEEK powder with a particle size of 50-75 μm is directly dried, the drying temperature is 120-150 ℃, and the drying time is 600-720 min.

[0059] 2) The pure PEEK material is formed by LPBF, the preheating temperature of the powder bed during the printing process is 325-335 ℃, the pre-powder bed thickness is 5 mm, the laser power is 14-16 W, the scanning speed is 2000-2500 mm / s, the layer thickness is 0.1 mm, the scanning interval is 0.1 mm, the scanning is performed once in each layer, and the layer-to-layer scanning angle is the same.

[0060] 3) After the printing is completed, the workpiece is naturally cooled, and the workpiece is finally removed after the powder is removed to obtain the pure PEEK material workpiece.

[0061] Comparative Example 2

[0062] The wide-temperature-range PEEK-based self-lubricating composite material powder directly mixed without pretreatment is formed by the LPBF process of the application, comprising the following steps:

[0063] 1) PEEK powder with a particle size of 50-75 μm is directly dried with MoS2 powder with a particle size of 1-10 μm, the drying temperature is 120-150 ℃, and the drying time is 600-720 min.

[0064] 2) In the wide-temperature-range PEEK-based self-lubricating composite material powder, polyether ether ketone accounts for 88% and MoS2 accounts for 12% by mass percentage. The PEEK powder and MoS2 powder treated in step 1) are mechanically mixed by a three-dimensional stirrer (SYH-20L) at a rotating speed of 200-300 r / min for 2-3 h.

[0065] 3) The forming cylinder preheating temperature of the powder bed before LPBF forming of the wide-temperature-range PEEK-based self-lubricating composite material is 320-330 ℃, the powder supply cylinder surface temperature is maintained at 240-280 ℃, and the pre-powder bed thickness is 4-6 mm. The LPBF forming process parameters are: laser power is 15-18 W, scanning speed is 2500-3000 mm / s, layer thickness is 0.1 mm, and scanning spacing is 0.1 mm. The laser scanning strategy in the LPBF forming process is multi-directional cross scanning, that is, scanning twice in each layer, the layer-in angle is 60-90°, and the layer-to-layer scanning path angle is 30-60°.

[0066] 4) After the LPBF printing is completed, the cylinder gradient heat treatment is performed on the workpiece, the workpiece is buried in the powder for 5-10 mm by continuous powder laying, the surface temperature is 300-320 ℃, the temperature is maintained for 1-2 h, then gradient cooling is performed at a rate of 10 ℃ / min, and the temperature is maintained for 0.5 h every 30-50 ℃.

[0067] 5) After step 4) is completed, the powder is removed after being cooled to room temperature, and the wide-temperature-range PEEK-based self-lubricating composite material workpiece is obtained.

[0068] Comparative Example 3

[0069] The wide-temperature-range PEEK-based self-lubricating composite material powder mixed after pretreatment is formed by the conventional LPBF process, comprising the following steps:

[0070] 1) PEEK powder was subjected to layer-by-layer high-temperature powder laying treatment in an LPBF device (HT-LPBF 300), with a powder laying layer thickness of 0.1 mm, a powder laying speed of 50-100 mm / s, a web temperature of 300-310 °C, and the PEEK powder after high-temperature powder laying treatment was recovered; before mixing, the MoS2 powder was dried in a vacuum drying box (DZF-6050) at 150-200 °C for 6-8 h. The particle size of the PEEK powder used was 50-100 μm, and the particle size of the MoS2 powder used was 1-10 μm.

[0071] 2) In the wide-temperature-range PEEK-based self-lubricating composite material powder, the polyether ether ketone accounted for 88% and the MoS2 accounted for 12% by mass percentage. The PEEK powder after step 1) treatment and the MoS2 powder were mechanically mixed by using a three-dimensional stirrer (SYH-20L) at a speed of 200-300 r / min for 2-3 h.

[0072] 3) The wide-temperature-range PEEK-based self-lubricating composite material was subjected to LPBF forming, with a preheating temperature of the powder bed during printing of 320-330 °C, a pre-powder bed thickness of 5 mm, a laser power of 15-18 W, a scanning speed of 2500-3000 mm / s, a layer thickness of 0.1 mm, a scanning interval of 0.1 mm, a layer scanning once, and a same layer scanning angle.

[0073] 4) After printing, the product was naturally cooled immediately, and finally the product was obtained by cleaning the powder to obtain a pure PEEK material product.

[0074] Friction and wear performance test: the product obtained in the above examples and comparative examples was subjected to friction and wear performance test, and the friction curve was shown in Figure 3 , and the test results were shown in Table 1:

[0075] Table 1 Friction and wear performance test results of products of examples and comparative examples

[0076]

[0077] As can be seen from Table 1, the self-lubricating composite material with a wide temperature range PEEK base obtained by adding MoS2 and pre-treating the powder, the friction coefficient and wear rate of the parts prepared by the specific LPBF optimization process in the wide temperature range of-150 DEG C to 150 DEG C are far lower than those of the self-lubricating composite material powder mixed directly without pre-treatment by the ordinary LPBF process, the self-lubricating composite material powder formed by the LPBF process of the application and the self-lubricating composite material powder formed by the conventional LPBF process after pre-treatment, the tribological properties of the PEEK material are greatly improved, the material and the forming process of the parts manufactured by the material and the forming process can be used in extreme environments such as space, and have a wide application prospect in the manufacturing of high and low temperature resistant moving friction components.

[0078] The above is only used to illustrate the technical idea of the application, and cannot limit the protection scope of the application, and any modification made according to the technical idea of the application on the basis of the technical scheme falls within the protection scope of the claims of the application.

Claims

1. A method for molding wide-temperature-range polyether ether ketone-based self-lubricating composite parts for LPBF, characterized in that, include: Polyetheretherketone powder and molybdenum disulfide powder were pretreated separately and then mixed evenly to obtain a wide-temperature-range polyetheretherketone-based self-lubricating composite material powder. Based on the part model, the wide temperature range polyether ether ketone-based self-lubricating composite material powder is used as raw material and laser powder bed melting technology is used for printing. After cooling, the wide temperature range polyether ether ketone-based self-lubricating composite material part is obtained. In the wide-temperature-range polyetheretherketone-based self-lubricating composite powder, the polyetheretherketone powder accounts for 85-95 wt%, and the molybdenum disulfide powder accounts for 5-15 wt%. The preprocessing includes: Polyetheretherketone (PEEK) powder was subjected to a high-temperature layer-by-layer powder spreading process in an LPBF (Liquid Per Flow) device. The powder layer thickness was 0.1 mm, the spreading speed was 50-100 mm / s, and the surface temperature was 300-310℃. Take molybdenum disulfide powder and dry it at 150~200℃ for 6~8 hours; In the process of printing and molding using laser powder bed melting technology, the laser scanning adopts a multi-directional cross scanning strategy, that is, scanning twice within each layer, with the included angle of the scanning path within the layer being 60~90° and the included angle of the scanning path between layers being 30~60°. After the laser powder bed melting technology is used for printing and molding, the part is subjected to in-cylinder gradient heat treatment. Powder is continuously spread to bury the part in the powder for 5-10 mm. The surface temperature is 300-320℃ and held for 1-2 hours. Then, gradient cooling is performed at a rate of 10℃ / min, and the part is held for 0.5 hours every 30-50℃ decrease until it reaches room temperature and is then removed.

2. The molding method for wide-temperature-range polyether ether ketone-based self-lubricating composite parts for LPBF according to claim 1, characterized in that, The pretreated polyetheretherketone powder and molybdenum disulfide powder were mechanically mixed at a speed of 200-300 r / min for 2-3 h.

3. The molding method for wide-temperature-range polyether ether ketone-based self-lubricating composite parts for LPBF according to claim 1, characterized in that, The particle size of polyetheretherketone powder is 50~100μm, and the particle size of molybdenum disulfide powder is 1~10μm.

4. The molding method for wide-temperature-range polyether ether ketone-based self-lubricating composite parts for LPBF according to claim 1, characterized in that, During the laser powder bed fusion printing process, the surface temperature of the powder supply cylinder is maintained at 240~280℃, the preheating temperature of the forming cylinder is 320~330℃, and the thickness of the pre-laid powder bed is 4~6 mm.

5. The molding method for wide-temperature-range polyether ether ketone-based self-lubricating composite parts for LPBF according to claim 1, characterized in that, The process parameters for printing using laser powder bed melting technology are as follows: laser power of 15~18 W, scanning speed of 2500~3000 mm / s, layer thickness of 0.1 mm, and scanning spacing of 0.1 mm.

6. Wide-temperature-range polyether ether ketone-based self-lubricating composite material parts for LPBF prepared by the molding method according to any one of claims 1 to 5.

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