A kind of high content carbon fiber polyaryletherketone pre-composite powder particle granule extrusion screw

Abstract

The utility model discloses a kind of high content carbon fiber polyaryletherketone pre-composite powder granule particle extrusion screw, including screw, the screw includes three parts of feed zone, compression zone and homogenization zone, the surface of the screw integrally formed has multiple groups of screw edge, and screw edge on screw gradually follows the gradual change structure from sparse to dense in feed zone, compression zone, homogenization zone in turn.The utility model discloses a kind of high content carbon fiber polyaryletherketone pre-composite powder granule particle extrusion screw, improves the function of feed zone and compression zone, to improve the high viscosity problem caused by high content carbon fiber, it is uniformly distributed with mixing protrusion between screw thread edge, screw pitch adopts the structure from sparse to dense, inner diameter keeps consistent, homogenization zone head is set as torpedo head, effectively solve the high viscosity problem generated due to high carbon fiber content of device, realize the rapid extrusion of pre-composite powder granule particle size, can be widely applied in injection molding and fused deposition processing field.

Description

Technical Field

[0001] This utility model relates to the field of injection molding and melt deposition processing technology, and in particular to a high-content carbon fiber polyaryletherketone precomposite powder extrusion screw. Background Technology

[0002] Polyaryletherketone (PAGE) is a high-performance thermoplastic engineering plastic with excellent high-temperature resistance, chemical stability, mechanical properties and biocompatibility. It has broad application prospects in aerospace, medical devices, automobile manufacturing and other fields. With the continuous development of science and technology, people have higher and higher requirements for extrusion screws of high-carbon fiber PAGE pre-composite powder granules.

[0003] Existing high-carbon fiber content polyaryletherketone (PAEK) pre-composite powder extrusion screws have certain drawbacks in use. To improve the performance of PAEK composites, modifications are often made by adding reinforcements; however, when the carbon fiber content is high, the viscosity of the composite melt increases, which significantly increases the difficulty of injection molding or fused deposition modeling. In existing technologies, parts with high carbon fiber content (50-60 wt%) are prone to surface embrittlement and breakage during stretching.

[0004] To achieve uniform dispersion of high-content carbon fibers in a poly(aryletherketone) matrix and improve processing performance, several patent documents have disclosed solutions from different directions. Chinese invention patent application CN202411945879.7 discloses a method for preparing poly(aryletherketone) ketone composite powder based on rapid phase separation and efficient solvent recovery using a high-boiling-point solidifier. Compared to traditional mechanical mixing, wet pre-composite high-content carbon fiber poly(aryletherketone) ketone powder can achieve efficient and uniform dispersion of components, resulting in a uniform distribution of carbon fibers within the poly(aryletherketone) ketone matrix. While this patent has solved the problem of uniformity in high-load melt interface composites, viscosity remains a challenge. One approach to address viscosity is to add a lubricant to the composite powder: Chinese invention patent application CN201210114931.5 discloses such a lubricant-based solution, but its method lacks universality and limits the overall performance of the composite material. Another approach is to optimize the screw base mechanism: Chinese invention patent CN202410911751.2 relates to the technology of twin-screw processing modified polyetheretherketone (PEEK) carbon fiber composite materials. However, the multi-feed port design of twin-screws is prone to problems such as powder clogging and uneven dispersion. Therefore, existing technologies still lack effective solutions for the extrusion molding of PEEK powder with a carbon fiber content of 40% or more, especially in addressing the two major pain points of rapid feeding of composite powder and smooth discharge of high-viscosity materials. To this end, we propose a high-content PEEK pre-composite powder extrusion screw. Utility Model Content

[0005] Technical problem solved: To address the shortcomings of existing technologies, this utility model provides a high-carbon fiber polyaryletherketone precomposite powder extrusion screw, which improves the functions of the feeding zone and compression zone. To mitigate the high viscosity problem caused by the high carbon fiber content, mixing protrusions are evenly distributed between the thread edges, the pitch adopts a structure from sparse to dense, the inner diameter remains consistent, and the head of the homogenization zone is designed as a torpedo head. This effectively solves the high viscosity problem caused by the high carbon fiber content of the device, and realizes rapid extrusion of precomposite powder particles. It can be widely used in injection molding and fused deposition modeling processes, and can effectively solve the problems in the background technology.

[0006] Technical Solution: To achieve the above objectives, the technical solution adopted by this utility model is as follows: a high-content carbon fiber polyaryletherketone precomposite powder extrusion screw, comprising a screw, which includes a feeding zone, a compression zone, and a homogenization zone. Multiple sets of screw ridges are integrally formed on the surface of the screw, and the screw ridges on the screw follow a gradual change in density from sparse to dense in the feeding zone, compression zone, and homogenization zone. Pins, i.e., mixing protrusions, are positioned around the outer wall of the screw. A clamping cylinder is connected to the screw, and a driving mechanism is connected to the clamping cylinder. The groove depth of the threaded grooves on the screw is consistent between the end near the clamping section and the far end. The feeding zone, compression zone, and homogenization zone sequentially enhance each other's functions.

[0007] Preferably, the inner diameter of the screw is 15mm, the length of the screw is 150mm, and the length-to-diameter ratio of the screw is 10:1.

[0008] Preferably, the groove depth of the threaded groove between the screw and the screw edge is consistent at the end near the clamping section and the far end, and is 1-1.5mm.

[0009] Preferably, the feeding zone and compression zone on the screw account for 76% of the total length, which is 114mm, the screw edge value increases from 10 to 12mm, the homogenization zone accounts for 24% of the total length, which is 36mm, and the distance between the screw edges is 15mm.

[0010] Preferably, the inner diameter of the head of the homogenization zone on the screw is slightly smaller than the inner diameter of the barrel, and the gap is maintained at 0.1-0.3 mm. The screw and the barrel are respectively made of MS1 steel and stainless steel.

[0011] Preferably, the pin has a diameter of 2.5 mm, a protrusion height of 0.8 mm, and a radial spacing angle of 36°.

[0012] Beneficial effects: Compared with the prior art, this utility model provides a high-content carbon fiber polyaryletherketone precomposite powder granule extrusion screw, which has the following beneficial effects: This high-content carbon fiber polyaryletherketone precomposite powder granule extrusion screw improves the function of the feeding zone and the compression zone. In order to improve the high viscosity problem caused by high carbon fiber content, the screw thread edges are evenly distributed with mixing protrusions, the pitch adopts a structure from sparse to dense, the inner diameter is kept consistent, and the head of the homogenization zone is set as a torpedo head. It effectively solves the high viscosity problem caused by high carbon fiber content in the device, realizes the rapid extrusion of precomposite powder granules, and can be widely used in injection molding and melt deposition processing. Through special mixing and stirring design, the mechanical properties of the product are improved.

[0013] The screw design incorporates a mixing protrusion, which is no higher than the thread edge. This protrusion reduces the probability of slippage between the powder / granule and the screw. The screw pitch follows a gradual transition from sparse to dense, which optimizes the high viscosity of high-content carbon fiber and effectively improves the flowability of high-content (40% and above) reinforced polyaryletherketone composite powder / granules, ensuring smooth discharge.

[0014] In view of the small particle size (3-5mm) of the pre-composite powder, the feeding section adopts a large lead thread design, which can realize the rapid conveying of the composite powder;

[0015] The pitch design from sparse to dense (i.e., the pitch of the compression section gradually decreases) allows the material to be gradually compressed during the conveying process, achieving a smooth transition of the compression ratio and avoiding melt overheating or fiber damage caused by excessive compression ratio.

[0016] The head of the homogenization zone adopts a "torpedo head" design, which can further compress and homogenize the melt, reduce shear fluctuations, and smoothly connect with the pin area of ​​the homogenization zone to avoid the formation of turbulence or dead corners, ensuring stable delivery of high-viscosity, high-filling materials. The entire high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw has a simple structure, is easy to operate, and performs better than traditional methods. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of an extrusion screw for high-content carbon fiber polyaryletherketone precomposite powder granules according to the present invention.

[0018] Figure 2 This is a schematic diagram of the screw body in the extrusion screw of a high-content carbon fiber polyarylether ketone precomposite powder granule according to the present invention.

[0019] In the diagram: 1. Screw; 2. Feeding zone; 3. Compression zone; 4. Homogenization zone; 5. Screw edge; 6. Pin; 7. Clamping cylinder; 8. Drive mechanism. Detailed Implementation

[0020] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are only some embodiments of this utility model, not all embodiments, and are only used to illustrate this utility model, and should not be regarded as limiting the scope of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] like Figure 1 , 2As shown, a high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw includes a screw 1, which comprises a feeding zone 2, a compression zone 3, and a homogenization zone 4. Multiple sets of screw ridges 5 are integrally formed on the surface of the screw 1, and the screw ridges 5 on the screw 1 follow a gradual change in density from sparse to dense on the feeding zone 2, compression zone 3, and homogenization zone 4. Pins 6, i.e., mixing protrusions, are positioned around the outer wall of the screw 1. A clamping cylinder 7 is connected to the screw 1, and a drive mechanism 8 is connected to the clamping cylinder 7. The depth of the threaded grooves on the screw 1 is... The end near the clamping section is consistent with the far end. The functions of the feeding zone 2, compression zone 3 and homogenization zone 4 are improved in sequence. The functions of the feeding zone and compression zone are improved. In order to improve the high viscosity problem caused by high carbon fiber content, mixing protrusions are evenly distributed between the thread edges. The pitch adopts a structure from sparse to dense. The inner diameter is consistent. The head of the homogenization zone is set as a torpedo head. It effectively solves the high viscosity problem caused by high carbon fiber content in the device, realizes the rapid extrusion of pre-composite powder particles, and can be widely used in injection molding and fused deposition modeling.

[0024] Furthermore, the inner diameter of screw 1 is 15mm, the length of screw 1 is 150mm, and the length-to-diameter ratio of screw 1 is 10:1.

[0025] Furthermore, the groove depth of the threaded groove between the screw 1 and the screw rib 5 is consistent at the end near the clamping section and the far end, and is 1-1.5mm in both cases.

[0026] Furthermore, the feeding zone 2 and compression zone 3 on screw 1 account for 76% of the total length, which is 114mm. The screw ridge 5 increases in length from 10 to 12mm. The homogenization zone 4 accounts for 24% of the total length, which is 36mm. The screw ridge 5 are 15mm apart.

[0027] Furthermore, the inner diameter of the head of the homogenization zone 4 on the screw 1 is slightly smaller than the inner diameter of the barrel, and the gap is maintained at 0.1-0.3mm. The screw 1 and the barrel are made of MS1 steel and stainless steel, respectively.

[0028] Furthermore, the pin 6 has a diameter of 2.5 mm, a protrusion height of 0.8 mm, and a radial spacing angle of 36°.

[0029] Example 1:

[0030] Continuous printing in fused deposition modeling

[0031] The material is a 40wt% carbon fiber reinforced polyether ketone ketone (PEKK) pre-composite powder with a particle size of 3-5mm and a carbon fiber length distribution of 1-3mm. The melting point of the material is 343℃, as measured by differential scanning calorimetry. The carbon fiber and PEKK matrix have achieved efficient and uniform dispersion after wet pre-composite process. The melt viscosity reaches 1200Pa·s at 380℃, which belongs to the high viscosity powder system.

[0032] The processing equipment is a desktop particle 3D printer. The power input connector is designed to match the 3D printing customization, with a Φ15mm single screw that is compatible with the screw of this utility model (inner diameter 15mm, length 150mm, length-to-diameter ratio 10:1) and a nozzle diameter of 0.8mm.

[0033] Select appropriate 3D printing process parameters: feed-compression section temperature 380℃, nozzle temperature 400℃ (can be flexibly adjusted during processing), printing platform temperature 120℃; infill speed / printing speed 25mm / s, layer thickness 0.2mm, infill density 95%.

[0034] After the powder / granule material enters the screw, thanks to the large lead design in the feeding zone, 20g of powder / granule material is continuously fed within 20 minutes without screw slippage. In the compression zone, the gradually changing screw pitch structure gradually compacts the material, and the mixing protrusions reduce slippage. The 0.2mm barrel gap in the homogenization zone effectively prevents material adhesion, and the "torpedo head" structure ensures smooth melt entry into the nozzle. Continuous printing for 2 hours is achieved without nozzle clogging, the melt extrusion flow rate stability error is ≤2%, and the printing path is continuous without interruptions.

[0035] The printed tensile sample (63.50mm×9.53mm×2mm) has a density of 94.2% and a tensile strength of 120MPa-150MPa after tensile performance testing. The bending sample (80mm×10mm×4mm) has a bending strength of 200MPa, which is 15% and 22% higher than that of products processed by existing technology, respectively. There is no pulverization on the fracture surface and the carbon fiber is tightly bonded to the PEEK matrix.

[0036] Example 2:

[0037] Machining of small precision components in injection molding

[0038] The pre-composite powder material with 40wt% carbon fiber reinforced polyether ketone ketone (PEKK) has a particle size of 3-5mm. The particle size distribution is uniform as detected by a laser particle size analyzer. The carbon fiber length distribution is 1-3mm. After wet pre-compositeing of carbon fiber and PEKK matrix, efficient and uniform dispersion has been achieved. The melt index is 8.2g / 10min (380℃, 5kg load), which belongs to the high viscosity powder material system.

[0039] The processing equipment is a miniature injection molding machine. The power input connector is customized to match the injection molding machine. It is a Φ15mm single screw that is compatible with the screw of this utility model (inner diameter 15mm, length 150mm, length-to-diameter ratio 10:1).

[0040] Select appropriate injection molding process parameters: barrel zone 1 temperature 360℃, zone 2 temperature 380℃, zone 3 temperature 390℃, nozzle temperature 390℃; screw speed 40-50 r / min, back pressure 3.5MPa, injection pressure 85MPa, holding pressure 50MPa.

[0041] After the equipment is started, the powder and granular material enter the screw feeding zone through the hopper. Due to the integrated design of the feeding zone and compression zone and the initial screw pitch of 15mm, the powder and granular material quickly fills the screw grooves without bridging or stagnation. As the screw rotates, the material is conveyed forward along the screw pitch structure from sparse to dense, achieving smooth compression. The mixing protrusions (36° intervals) with a diameter of 2.5mm and a height of 0.8mm between the screw edges create high-frequency shearing and agitation of the material. Microscopic observation shows that the carbon fibers are uniformly dispersed without local agglomeration. After being further homogenized by the "torpedo head," the material is ejected from the nozzle in a stable molten state without pulsation or blockage.

[0042] The machined small precision gear components (inner diameter 20mm, module 0.5) have a smooth surface with no exposed fibers or bubbles. Tested by a universal testing machine, the tensile strength reaches 210MPa, which is 18% higher than that of products with the same formula processed by conventional screws, thus solving the problem of surface embrittlement in traditional processing.

[0043] Working principle: This utility model includes a screw 1, a feeding zone 2, a compression zone 3, a homogenization zone 4, screw ribs 5, a pin 6, a clamping cylinder 7, and a drive mechanism 8. It improves the functions of the feeding zone and the compression zone. To improve the high viscosity problem caused by high carbon fiber content, mixing protrusions are evenly distributed between the screw ribs. The screw pitch adopts a structure from sparse to dense, and the inner diameter remains consistent. The head of the homogenization zone is set as a torpedo head, which effectively solves the high viscosity problem caused by high carbon fiber content. It realizes rapid extrusion of pre-composite powder particles and can be widely used in injection molding and fused deposition modeling.

[0044] It should be noted that, in this document, relational terms such as first and second (number one, number two), etc., are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw, comprising a screw (1), characterized in that: The screw (1) includes three parts: a feeding zone (2), a compression zone (3), and a homogenization zone (4). The surface of the screw (1) is integrally formed with multiple sets of screw ridges (5), and the screw ridges (5) on the screw (1) follow a gradual structure from sparse to dense on the feeding zone (2), compression zone (3), and homogenization zone (4). The outer wall of the screw (1) is positioned with pins (6), which are mixing protrusions. The screw (1) is connected to a clamping cylinder (7), and the clamping cylinder (7) is connected to a driving mechanism (8). The groove depth of the threaded groove on the screw (1) is consistent with the depth at the end near the clamping section and the end far from it. The feeding zone (2), compression zone (3), and homogenization zone (4) are sequentially upgraded in function.

2. The high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw according to claim 1, characterized in that: The inner diameter of the screw (1) is 15mm, the length of the screw (1) is 150mm, and the length-to-diameter ratio of the screw (1) is 10:

1.

3. The high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw according to claim 1, characterized in that: The groove depth of the threaded groove between the screw (1) and the screw edge (5) is consistent at the end near the clamping section and the far end, and is 1-1.5mm.

4. The high-content carbon fiber polyaryletherketone precomposite powder extrusion screw according to claim 1, characterized in that: The feeding zone (2) and compression zone (3) on the screw (1) account for 76% of the total length, which is 114mm. The screw ridge (5) value increases from 10 to 12mm. The homogenization zone (4) accounts for 24% of the total length, which is 36mm. The screw ridge (5) is 15mm apart.

5. The high-content carbon fiber polyaryletherketone pre-composite powder extrusion screw according to claim 1, characterized in that: The inner diameter of the head of the homogenization zone (4) on the screw (1) is slightly smaller than the inner diameter of the barrel, and the gap is maintained at 0.1-0.3mm. The screw (1) and the barrel are made of MS1 steel and stainless steel, respectively.

6. The high-content carbon fiber polyaryletherketone precomposite powder extrusion screw according to claim 1, characterized in that: The pin (6) has a diameter of 2.5 mm and a protrusion height of 0.8 mm, and the radial spacing angle of the pin (6) is 36°.

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