AU2020100834A4 - Compression molding process of carbon fiber reinforced composite material - Google Patents
Compression molding process of carbon fiber reinforced composite material Download PDFInfo
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- AU2020100834A4 AU2020100834A4 AU2020100834A AU2020100834A AU2020100834A4 AU 2020100834 A4 AU2020100834 A4 AU 2020100834A4 AU 2020100834 A AU2020100834 A AU 2020100834A AU 2020100834 A AU2020100834 A AU 2020100834A AU 2020100834 A4 AU2020100834 A4 AU 2020100834A4
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
- B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
- B22F7/02—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/54—Component parts, details or accessories; Auxiliary operations, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
- B29C2035/0211—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould resistance heating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
- B29C2035/1658—Cooling using gas
- B29C2035/1666—Cooling using gas dried air
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Composite Materials (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Thermal Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
- Moulding By Coating Moulds (AREA)
Abstract
The present invention provides a compression molding process of carbon fiber
reinforced composite material. Because an adaptive molding action is innovatively
adopted during the processing for the carbon fiber reinforced composite material,
while a carbon fiber reinforced composite material blank is molded, an indenter of an
upper mold can adapt to the surface of the blank to make corresponding actions. The
entire molding process can dynamically adjust the indenter to adapt to the changing
blank surface. After the actions, the internal stress of carbon fiber cloth layers is
absorbed and the aluminum solution between the carbon fiber cloth layers is
sufficiently uniformly impregnated, so that the mechanical property of the carbon
fiber reinforced composite material after the molding is significantly improved.
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18 19
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11 75 13A
11B B
12
64\ -7 2
16- 14
FIG. 1
Description
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b4
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18 19
8
11 75 13A 11B B
12
64\ -7 2 16- 14
FIG. 1
[0001] The present invention relates to the field of molding of composite material, and particularly relates to a compression molding process of carbon fiber reinforced composite material.
[0002] As novel composite material, carbon fiber reinforced composite material has the advantages of low specific gravity, high strength, high elastic tensile modulus, small thermal expansion coefficient, and good anti-vibration and vibration absorption performance, and thus has always been a research hotspot. The molding process of the carbon fiber reinforced composite material has a crucial influence on the performance of the carbon fiber reinforced composite material. In the prior art, the molding process of the carbon fiber reinforced composite material generally adopts a compression molding mode. However, the molding process in the prior art focuses on temperature and a closed environment, and has no special requirement for the pressure in the compression molding process, as long as the carbon fiber reinforced composite material can be molded. If the size of the processed carbon fiber reinforced composite material is small, the influence of the compression molding force is also small, but when large carbon fiber reinforced composite material is subjected to compression molding, the compression molding force plays a crucial role in the performance of the carbon fiber reinforced composite material. For example, patent literature 1 discloses a preparation method for a carbon fiber reinforced aluminum-based layered composite board, which also uses the compression molding process and uses a vibration worktable in the molding process so that an aluminum solution wets carbon fibers through vibration. Although this process can avoid forming a brittle compound on the surfaces of the carbon fibers and make the structure denser, due to the increase of the vibration worktable, the structure is more complicated. At the same time, more bubbles may be generated in the impregnated carbon fibers due to the influence of the vibration worktable. A carbon fiber cloth layer may wrinkle due to the vibration, thereby further affecting the mechanical property of the carbon fiber composite material. For example, patent literature 2 discloses a vacuum compression molding device of carbon fiber composite material. A vacuuming device is added in the molding device so that the carbon fiber material in a mold can be impregnated under the action of negative pressure. At the same time, three speeds are used to control pressing speed, but a vacuum negative pressure effect is limited. At the same time, although slow contact can improve the impregnation of resin and carbon fibers in the carbon fiber composite material to a certain extent, the improvement degree is limited and cannot release the stress in the carbon fiber composite material. For example, patent literature 3 discloses a multi-point forming method of an aluminum alloy aircraft integral wall plate, which adopts a multi-point mold structure on an upper mold and a lower mold. Multi-point molds are used to adapt to manufacture a curved aluminum alloy wall plate with more complicated shape, but the molds have no linkage. For example, patent literature 4 discloses a clamping device with a variable-stiffness flexible surface, which uses a plurality of piston cylinders jointly connected to a magnetorheological valve, and realizes the movement of the plurality of piston cylinders by turning on and off the magnetorheological valve to adapt to different surfaces for clamping. However, in the clamping device, each piston cylinder is independent, and cannot be linked. Moreover, the clamping device can only adapt to different flexible surfaces, and does not need to actively apply an external force to the flexible surfaces to change the flexible surfaces.
[0003] [Patent literature 1] CN103397284A
[0004] [Patent literature 2] CN105034410A
[0005] [Patent literature 3] CN104646475B
[0006] [Patent literature 4] CN1799784A
[0007] In conclusion, the prior art fails to provide a compression molding process capable of performing adaptive compression molding actions based on the surface shape characteristics of carbon fiber reinforced composite material, eliminating the stress in the carbon fiber reinforced composite material and simultaneously performing active compression molding actions to improve the molding characteristics of the carbon fiber reinforced composite material. Based on this, the present application provides a compression molding process of the carbon fiber reinforced composite material.
[0008] In order to overcome the defects of the existing compression molding process, the present invention provides a technical solution: a compression molding process of carbon fiber reinforced composite material comprises the following steps:
[0009] (I) placing blanks:
[0010] according to an alternating sequence of a carbon fiber cloth layer, an aluminum powder layer and a carbon fiber cloth layer, placing the blanks into a lower mold cavity of a lower mold of a hot press molding device;
[0011] (II) semi-mold closing:
[0012] driving a molding cylinder of the hot press molding device to act so that an indenter of the upper mold quickly reaches the lower mold cavity and comes into contact with the lower mold cavity to form a semi-mold closing state;
[0013] (III) semi-mold closing environment processing:
[0014] turning on a vacuum pump to vacuum a space in the lower mold cavity; simultaneously, starting a heating resistance wire A and a heating resistance wire B in the indenter and the lower mold for heating, so that a negative pressure in the lower mold cavity reaches a certain value and then the vacuum pump is turned off; simultaneously, enabling the heating resistance wire A and the heating resistance wire B to continue to heat until the melting temperature of aluminum powder reaches 660°C ±3C; and stopping heating;
[0015] (IV) continuing mold closing:
[0016] starting the molding cylinder to act again, so that the indenter continues to descend; and closing the molding cylinder when the indenter comes into contact with a highest point H of blank deformation;
[0017] (V) adaptive molding action:
[0018] starting a balance rod to make an extension action; driving the indenter to continue to descend slowly; disconnecting four adaptive telescopic cylinders evenly arranged around the balance rod from a hydraulic pump; communicating oil paths between the rodless cavities of the adaptive telescopic cylinders to form a dynamic balance cylinder group, so that the indenter which freely rotates around the balance rod is controlled by the dynamic balance cylinder group to act; when the indenter touches the highest point H of blank deformation, generating, by the blank at H, an obstructing force on the adaptive telescopic cylinder located here, thereby squeezing hydraulic oil in the adaptive cylinder through a connecting pipeline into the other three adaptive telescopic cylinders; while the oil is squeezed into the other three adaptive telescopic cylinders, generating, by the oil, an anti-pressing force on the blank at this place, to squeeze excess aluminum solution to other places; enabling the slow pressing action of the balance rod and the balance cylinder group action formed by the four communicated adaptive cylinders to jointly act on the indenter to act on the blanks; and performing an adaptive molding action on the blanks;
[0019] (VI) adjusting levelness of the indenter of the upper mold:
[0020] after the adaptive molding action is completed, stopping extending by the balance rod so that a solenoid valve among the adaptive telescopic cylinders acts; cutting off the communication among the adaptive telescopic cylinders; then choosing to fill the corresponding adaptive cylinders according to the state of the indenter detected by a level meter installed on the upper end of the indenter, thereby adjusting the levelness of the indenter until the levelness detected by the level meter reaches a standard; and stopping the action for 60s;
[0021] (VII) cooling:
[0022] after reaching a predetermined time, driving the molding cylinder to contract and driving the indenter to move up; when a lower surface of the indenter is located between a cold air pipe and the vacuum pipe, outputting cold air from the cold air pipe for rapid cooling; and stopping cooling when the temperature reaches 60°C;
[0023] (VIII) taking out the blanks:
[0024] taking out the carbon fiber reinforced composite material after compression molding to obtain the processed carbon fiber composite material.
[0025] Preferably, the certain value in the step (III) enables a vacuum degree in the lower mold cavity to be below 1 KPa.
[0026] Preferably, in the step (V), while the balance rod conducts slow molding, the balance cylinder group formed by the four communicated adaptive cylinders always adjusts the indenter adaptively; and the structural design of the balance cylinder group can also absorb pressure in the blanks.
[0027] Preferably, in the step (V), when starting the balance rod to make the extension action and driving the indenter to continue to descend slowly, the speed of the balance rod satisfies: the oil pressure in the balance rod reaches 1OMPa, and the entire adaptive molding action process continues for more than 60s.
[0028] Preferably, a hot press molding device in the compression molding process of the carbon fiber reinforced composite material comprises a base, a guide rod, a top frame, a molding cylinder, an upper mold and a lower mold; the guide rod is fixedly connected between the base and the top frame; the upper mold is slidingly arranged on the guide rod; the molding cylinder is connected between the upper mold and the top frame to drive the upper mold to slide up and down along the guide rod; the lower mold is fixedly arranged on the base; a lower mold cavity is arranged in the middle of the lower mold; the upper mold comprises a sliding valve seat and an adaptive indenter component; the sliding valve seat is penetrated on the guide rod; the adaptive indenter component comprises a balance rod, adaptive telescopic cylinders and an indenter; the upper ends of the balance rod and the adaptive cylinders are fixedly connected to the lower end of the sliding valve seat; the lower ends of the balance rod and the adaptive cylinders are rotatably connected to the upper end of the indenter; the indenter is of a rectangular structure; the balance rod is installed at an intersection of two central axes of the indenter of the rectangular structure; four adaptive cylinders are arranged; two adaptive cylinders are respectively arranged on each of the two central axes; the two adaptive cylinders on the same central axis are away from the balance rod by the same distance; the four adaptive cylinders are communicated through a pipeline; the balance rod is also of a telescopic cylinder structure to drive the indenter to conduct compression molding on the carbon fiber reinforced composite material; during the compression molding, four communicated adaptive cylinders form a dynamic balance cylinder group for actions; and during the compression molding, the active pressurizing action of the balance rod and the action of the dynamic balance cylinder group jointly form an adaptive molding action.
[0029] Preferably, the dynamic balance cylinder group adapts to the surface of the carbon fiber reinforced composite material so that the indenter performs dynamic balance adjustment and the unevenly distributed aluminum solution in the carbon fiber cloth layer is evenly distributed during the compression molding, thereby further improving the impregnation effect of the carbon fiber cloth layer.
[0030] Preferably, while improving the impregnation effect of the carbon fiber cloth layer, the dynamic balance cylinder group can absorb the stress in the carbon fiber cloth layer, thereby further improving the mechanical property of the carbon fiber reinforced composite material and simultaneously performing the compression molding and impregnation procedures.
[0031] Preferably, after the balance rod completes the compression molding procedure, the communicated oil paths among the adaptive cylinders are closed and the adaptive cylinders are filled through a hydraulic pump, so that the indenter is kept horizontal to ensure the flatness of the upper surface of the carbon fiber reinforced composite material.
[0032] Preferably, a hinged ball head A and a hinged ball head B are used to realize the rotatable connection of the balance rod, the adaptive telescopic cylinders and the indenter respectively.
[0033] Preferably, a heating resistance wire B is arranged in the lower mold; a heating resistance wire A is arranged in the indenter; a thermal insulating layer B is arranged on the lower end of the heating resistance wire B in the lower mold; a thermal insulating layer A is arranged on the back surface of the indenter; and the heating resistance wire A and the heating resistance wire B are of spiral structures, so that the temperature in the upper mold and the indenter is increased evenly.
[0034] Preferably, a vacuum pipe is arranged in the lower mold cavity, and the vacuum pipe is communicated with the vacuum pump; and in order to quickly cool the carbon fiber composite material, the cold air pipe is also arranged in the lower mold cavity, and cold air is outputted from the cold air pipe.
[0035] Preferably, the vacuum pipe is located at the upper end of the lower mold cavity; the cold air pipe is located at the lower end of the vacuum pipe; and when the molded carbon fiber composite material needs to be cooled, the indenter is raised so that the indenter is located between the vacuum pipe and the cold air pipe to release the cold air for rapid cooling.
[0036] Preferably, in order to ensure that a sealed space can be formed in the lower mold cavity, a sealing plug structure is arranged on the periphery of the indenter to ensure that the sealed space is formed in the lower mold cavity during the micro-rotation of the indenter.
[0037] Preferably, a hydraulic oil path system in the sliding valve seat comprises an oil tank, a hydraulic pump and two-position two-way solenoid valves; the hydraulic pump is respectively connected with the balance rod and the rod cavities of the adaptive telescopic cylinders through an oil inlet pipeline; the hydraulic pump is communicated with the balance rod and the adaptive telescopic cylinders through the oil inlet pipeline; the two-position two-way solenoid valves are arranged on the oil inlet pipelines; and four adaptive telescopic cylinders are arranged, i.e., a first adaptive telescopic cylinder, a second adaptive telescopic cylinder, a third adaptive telescopic cylinder and a fourth adaptive telescopic cylinder. The first adaptive telescopic cylinder and the second adaptive telescopic cylinder are communicated through a communicating pipeline, the second adaptive telescopic cylinder and the third adaptive telescopic cylinder are communicated through a communicating pipeline, and the third adaptive telescopic cylinder and the fourth adaptive telescopic cylinder are communicated through a communicating pipeline; the two-position two-way solenoid valves are respectively arranged on the communicating pipelines; an oil inlet cavity of the balance rod is also communicated with the oil tank through an oil return pipeline; and a two-position two-way solenoid valve is arranged on the oil return pipeline. The rod cavities of thefirst adaptive telescopic cylinder, the second adaptive telescopic cylinder, the third adaptive telescopic cylinder and the fourth adaptive telescopic cylinder are communicated with the oil tank through another oil return pipeline; and a two-position two-way solenoid valve is arranged on a bus of the another oil return pipeline.
[0038] Preferably, in order to reset and adjust each adaptive telescopic cylinder, return springs are sleeved in the rod cavities.
[0039] Preferably, in order to detect the position of the indenter, a level detector is installed on the upper part of the indenter.
[0040] The present invention has the following beneficial effects that:
[0041] 1) In the compression molding process of the present invention, considering that the carbon fiber reinforced composite material is of a structure in which the aluminum powder layer and the carbon fiber cloth layer are cross-laminated, in order to ensure the connection strength between the layers and to ensure that the aluminum powder which is converted into the aluminum solution can be impregnated into each comer of the carbon fiber cloth layer to make the impregnation even, the upper mold is arranged such that the middle is hinged to the sliding valve seat through the balance rod and the structures of the adaptive telescopic cylinders that can be linked are evenly arranged around the upper mold. Through the structural arrangement, during the compression molding, the molding cylinder drives the upper mold to move down, and the indenter at the lower end of the upper mold can rotate freely around the balance rod. When the upper mold comes into contact with the composite material to be molded, the molding cylinder stops acting, and the indenter can adapt to the shape of the upper surface of the composite material and relatively rotate. If a large amount of aluminum solution infiltrates into the carbon fiber cloth in the composite material, the upper surface of the composite material of this part swells. The indenter firstly comes into contact with the surface of the composite material of this part, and the adaptive telescopic cylinder corresponding to the upper end of this part is contracted by force. The oil of the rodless cavities enters other adaptive telescopic cylinders through the linked oil paths. Because the oil produces a reaction force on a telescopic rod when entering the oil paths with a smaller size than the rodless cavities from the rodless cavities, at this time, the surface of the carbon fiber composite material of the contact part is subjected to a small pressure, which can promote more aluminum solution of this part to flow around without squeezing out the aluminum solution. The adaptive telescopic cylinders are started to extend. The action speed of the adaptive telescopic cylinders is set to be slow. The adaptive telescopic cylinders extend to the thickness required to be processed for the carbon fiber reinforced composite material. In the slow pressurization process, because the adaptive telescopic cylinders evenly arranged on the periphery are communicated, the adaptive telescopic cylinders can adapt to the change of the surface shape of the composite material in the pressurization process to achieve a dynamic balance state, so that the aluminum solution in the composite material is impregnated evenly. At the same time, the adaptive telescopic cylinder structures can absorb the internal stress generated by the carbon fiber reinforced composite material in the compression molding process, thereby further ensuring the mechanical property of the composite material. This processing mode combines the active pressurization of the balance rod and the passive deformation of the adaptive telescopic cylinders to form a unique adaptive compression molding action, which makes the aluminum solution evenly impregnated, eliminates the internal stress of the composite material, and further improves the mechanical property of the carbon fiber reinforced composite material.
[0042] 2) In the compression molding process of the present invention, the hydraulic cylinders with two movement speeds are used for action. When the compression molding work is started, the molding cylinder which is operated at high speed is used to perform the in-place action. When the carbon fiber composite material needs to be molded, the balance rod that can be finely controlled is driven to make telescopic slow compression molding actions, which adapts to the characteristics of the compression molding process of the composite material. The cylinders that require the actions in different speed ranges are separately arranged. Compared with the setting of different speed movement ranges for the same cylinder, the arrangement of the cylinder is relatively simple, and the characteristics of different cylinders are fully utilized.
[0043] 3) In the compression molding process of the present invention, in order to ensure the flatness of the finally molded composite material, after the balance rod stops acting, the valves among the adaptive telescopic cylinders are in a cut-off state; the adaptive telescopic cylinders are filled with liquid; and the levelness of the indenter is adjusted to ensure the flatness of the carbon fiber reinforced composite material after the compression molding.
[0044] 4) In the compression molding process of the present invention, the vacuum pipe and the cold air pipe are simultaneously arranged in the lower mold, which adapts to the vacuuming and the cooling of the molds. In the cooling process, the cold air pipe and the vacuum pipe are not communicated, so as to ensure that the cold air is not sucked into the vacuum pipe during cooling, to further ensure the operation safety of the components communicated with the vacuum pipe, such as valves and vacuum pumps.
[0045] 5) In the compression molding process of the present invention, the heating resistance wires of annular structures are arranged in the upper mold and the lower mold, which can more ensure the uniformity of heating compared with the existing heating resistance wire.
[0046] 6) In the compression molding process of the present invention, in order to adapt to the actions of the molding cylinder, the balance rod and the adaptive telescopic cylinders, a special hydraulic loop is provided. The hydraulic loop is arranged in the sliding valve seat, and the hydraulic loop structure is arranged away from the heating resistance wires, which further ensures the safety of the hydraulic action and ensures the action safety of the components of the hydraulic loop. The oil path structures that control the actions of the molding cylinder, the balance rod and the adaptive telescopic cylinders are integrated into the sliding valve seat, so that the hydraulic structure is simple and safe.
[0047] Fig. 1 is a structural schematic diagram of a compression molding device used in a compression molding process of the present invention;
[0048] Fig. 2 is an enlarged view of Fig. 1;
[0049] Fig. 3 is a A-A view in Fig. 1;
[0050] Fig. 4 is a schematic diagram of a shape of a heating resistance wire A of a B-B view in Fig. 1;
[0051] Fig. 5 is a diagram of an oil path of a hydraulic cylinder;
[0052] Fig. 6 is a flow chart of a compression molding process of the present invention;
[0053] Fig. 7 is a structural schematic diagram of semi-mold closing;
[0054] Fig. 8 is a schematic diagram when an indenter comes into contact with a blank; and
[0055] Fig. 9 is a schematic diagram of a position of an indenter during cooling.
[0056] List of reference numerals
[0057] 1. base; 2. guide rod; 3. top frame; 4. molding cylinder; 5. upper mold; 6. lower mold; 7. sliding valve seat; 8. adaptive indenter component; 9. lower mold cavity; 10. carbon fiber reinforced composite material; 11. vacuum pipe; 12. cold air pipe; 13. heating resistance wire A; 14. heating resistance wire B; 15. thermal insulating layer A; 16. thermal insulating layer B; 17. indenter; 18. balance rod; 19. adaptive telescopic cylinder; 20. hinged ball head A; 21. hinged ball head B; 22. carbon fiber cloth layer; 23, aluminum powder layer; 24. hydraulic pump; 25. oil tank; 26. two-position two-way solenoid valve; 19-1. first adaptive telescopic cylinder; 19-2. second adaptive telescopic cylinder; 19-3. third adaptive telescopic cylinder; and 19-4. fourth adaptive telescopic cylinder.
[0058] The embodiments of the present invention will be described below with reference to the drawings.
[0059] As shown in Figs. 1-5, a hot press molding device in the compression molding process of the carbon fiber reinforced composite material in the present invention comprises a base 1, a guide rod 2, a top frame 3, a molding cylinder 4, an upper mold 5 and a lower mold 6; the guide rod 2 is fixedly connected between the base 1 and the top frame 2; the upper mold 5 is slidingly arranged on the guide rod 2; the molding cylinder 4 is connected between the upper mold 5 and the top frame 3 to drive the upper mold 5 to slide up and down along the guide rod 2; the lower mold 6 is fixedly arranged on the base 1; a lower mold cavity 9 is arranged in the middle of the lower mold 6; the carbon fiber reinforced composite material 10 is placed in the lower mold cavity 9 for compression molding; the upper mold 5 comprises a sliding valve seat 7 and an adaptive indenter component 8; and the sliding valve seat 7 is penetrated on the guide rod 2. The adaptive indenter component 8 comprises a balance rod 18, adaptive telescopic cylinders 19 and an indenter 17; the upper ends of the balance rod 18 and the adaptive cylinders 19 are fixedly connected to the lower end of the sliding valve seat 7; and the lower ends of the balance rod 18 and the adaptive cylinders 19 are rotatably connected to the upper end of the indenter 17. As shown in Fig. 3, the indenter 17 is of a rectangular structure; the balance rod 18 is installed at an intersection of two central axes of the indenter 17 of the rectangular structure; four adaptive cylinders 19 are arranged; two adaptive cylinders are respectively arranged on each of the two central axes; the two adaptive cylinders 19 on the same central axis are away from the balance rod 18 by the same distance; the four adaptive cylinders 19 are communicated through a pipeline; the balance rod 18 is also of a telescopic cylinder structure to drive the indenter 17 to conduct compression molding on the carbon fiber reinforced composite material 10; and during the compression molding, four communicated adaptive cylinders 19 form a dynamic balance cylinder group for actions. The dynamic balance cylinder group adapts to the surface of the carbon fiber reinforced composite material 10 so that the indenter 17 performs dynamic balance adjustment and the unevenly distributed aluminum solution in the carbon fiber cloth layer is evenly distributed during the compression molding, thereby further improving the impregnation effect of the carbon fiber cloth layer. Meanwhile, the dynamic balance cylinder group can absorb the stress in the carbon fiber cloth layer, thereby further improving the mechanical property of the carbon fiber reinforced composite material and synchronously performing the compression molding and impregnation procedures. After the balance rod 18 completes the compression molding procedure, the communicated oil paths among the adaptive cylinders 19 are closed and the adaptive cylinders 19 are filled through a hydraulic pump 24, so that the indenter 17 is kept horizontal to ensure the flatness of the upper surface of the carbon fiber reinforced composite material. This processing mode combines the active pressurization of the balance rod and the passive deformation of the adaptive telescopic cylinders to form a unique adaptive compression molding action, which makes the aluminum solution evenly impregnated, eliminates the internal stress of the composite material, and further improves the mechanical property of the carbon fiber reinforced composite material.
[0060] Preferably, a hinged ball head A20 and a hinged ball head B21 are used to realize the rotatable connection of the balance rod 18, the adaptive telescopic cylinders 19 and the indenter 17 respectively.
[0061] Preferably, in order to heat the carbon fiber composite material 10 in the lower mold, a heating resistance wire B14 is arranged in the lower mold 6; a heating resistance wire A13 is arranged in the indenter 17; a thermal insulating layer B16 is arranged on the lower end of the heating resistance wire B14 in the lower mold 6; and a thermal insulating layer A15 is arranged on the back surface of the indenter 17. As shown in Fig. 4, the heating resistance wire A13 and the heating resistance wire B14 are of spiral structures, so that the temperature in the upper mold and the indenter is increased evenly.
[0062] Preferably, in order to ensure the vacuum space when the carbon fiber composite material 10 is molded, a vacuum pipe 11 is arranged in the lower mold cavity 9, and the vacuum pipe 11 is communicated with the vacuum pump; and in order to quickly cool the carbon fiber composite material 10, a cold air pipe 12 is also arranged in the lower mold cavity 9, and cold air is outputted from the cold air pipe 12.
[0063] Preferably, in order to protect the vacuum pump, the vacuum pipe 11 is located at the upper end of the lower mold cavity 9; and the cold air pipe 12 is located at the lower end of the vacuum pipe 11. In this way, after the indenter 17 comes into contact with the lower mold cavity 9, the vacuum pump is started to suck the vacuum. Since the temperature in the lower mold cavity 9 has not risen to a high temperature, hot air can be prevented from being sucked, thereby protecting the vacuum pump. After the vacuum is sucked, the indenter 17 continues to press down. At this time, the indenter 17 passes over the vacuum pipe 11, so that the vacuum pipe 11 is located outside the lower mold cavity 9 to avoid being affected by high temperature gas. When the molded carbon fiber composite material 10 needs to be cooled, the indenter 17 is raised so that the indenter 17 is located between the vacuum pipe 11 and the cold air pipe 12 to release the cold air for rapid cooling. Due to this arrangement, the vacuum pipe 11 does not suck the cold air when cooling, thereby further protecting the vacuum pump.
[0064] Preferably, in order to ensure that a sealed space can be formed in the lower mold cavity 9, a sealing plug structure is arranged on the periphery of the indenter 17 to ensure that the sealed space is formed in the lower mold cavity during the micro-rotation of the indenter 17.
[0065] As shown in Fig. 5, a hydraulic oil path system in the sliding valve seat 7, as shown in the figure, comprises an oil tank 25, a hydraulic pump 24 and two-position two-way solenoid valves 26; the hydraulic pump 24 is respectively connected with the balance rod 18 and the rod cavities of the adaptive telescopic cylinders 19 through an oil inlet pipeline; the hydraulic pump 24 is communicated with the balance rod 18 and the adaptive telescopic cylinders 19 through the oil inlet pipeline; the two-position two-way solenoid valves 26 are arranged on the oil inlet pipelines; and four adaptive telescopic cylinders 19 are arranged, i.e., a first adaptive telescopic cylinder 19-1, a second adaptive telescopic cylinder 19-2, a third adaptive telescopic cylinder 19-3 and a fourth adaptive telescopic cylinder 19-4. The first adaptive telescopic cylinder 19-1 and the second adaptive telescopic cylinder 19-2 are communicated through a communicating pipeline, the second adaptive telescopic cylinder 19-2 and the third adaptive telescopic cylinder 19-3 are communicated through a communicating pipeline, and the third adaptive telescopic cylinder 19-3 and the fourth adaptive telescopic cylinder 19-4 are communicated through a communicating pipeline; the two-position two-way solenoid valves 26 are respectively arranged on the communicating pipelines; an oil inlet cavity of the balance rod 18 is also communicated with the oil tank 25 through an oil return pipeline; and a two-position two-way solenoid valve 26 is arranged on the oil return pipeline. The rod cavities of the first adaptive telescopic cylinder 19-1, the second adaptive telescopic cylinder 19-2, the third adaptive telescopic cylinder 19-3 and the fourth adaptive telescopic cylinder 19-4 are communicated with the oil tank 25 through another oil return pipeline; and a two-position two-way solenoid valve 26 is arranged on a bus of the another oil return pipeline.
[0066] Preferably, in order to reset and adjust each adaptive telescopic cylinder 19, return springs are sleeved in the rod cavities.
[0067] Preferably, in order to detect the position of the indenter 17, a level detector is installed on the upper part of the indenter 17.
[0068] As shown in Fig. 6, a compression molding process of the carbon fiber reinforced composite material in the present invention comprises the following steps:
[0069] I Placing blanks:
[0070] As shown in Fig. 2, according to an alternating sequence of a carbon fiber cloth layer, an aluminum powder layer and a carbon fiber cloth layer, placing the blanks into a lower mold cavity of a lower mold of a hot press molding device;
[0071] II Semi-mold closing:
[0072] Driving a molding cylinder 4 of the hot press molding device to act so that the indenter 17 of the upper mold quickly reaches the lower mold cavity 9 and comes into contact with the lower mold cavity 9; because the shape of the indenter 17 is matched with the lower mold cavity 9, a closed space is formed in the lower mold cavity 9 to form a semi-mold closing state; at this time, stopping driving the molding cylinder 4, for convenience of explanation, as shown in Fig. 7;
[0073] III Semi-mold closing environment processing:
[0074] Turning on the vacuum pump to vacuum a space in the lower mold cavity 9; simultaneously, starting a heating resistance wire A and a heating resistance wire B in the indenter 17 and the lower mold 6 for heating, so that a negative pressure in the lower mold cavity 9 reaches a certain value and then the vacuum pump is turned off; preferably, the vacuum degree in the lower mold cavity 9 is below 1 KPa, which is conducive to the precipitation of the air in the fiber bundles of the composite material; simultaneously, enabling the heating resistance wire A and the heating resistance wire B to continue to heat until the melting temperature of aluminum powder reaches 660°C ±3C; and stopping heating;
[0075] IV Continuing mold closing:
[0076] Starting the molding cylinder 4 to act again, so that the indenter 17 continues to descend; at this time, due to different impregnation degrees of the aluminum solution between the carbon fiber cloth layers, the carbon fiber cloth layers are slightly deformed; and closing the molding cylinder 4 when the indenter 17 comes into contact with a highest point H of blank deformation, as shown in Fig. 8;
[0077] V Adaptive molding action:
[0078] Starting the balance rod 18 to make an extension action; driving the indenter 17 to continue to descend slowly; disconnecting four adaptive telescopic cylinders evenly arranged around the balance rod 18 from the hydraulic pump; communicating oil paths between the rodless cavities of the adaptive telescopic cylinders to form a dynamic balance cylinder group, so that the indenter 17 which freely rotates around the balance rod 18 is controlled by the dynamic balance cylinder group to act. Specifically, as shown in Fig. 8, when the indenter 17 touches the highest point H of blank deformation, because the balance rod 18 extends, the indenter continues to descend slowly; at this time, the blank at H generates an obstructing force on the adaptive telescopic cylinder 19 located here, thereby squeezing hydraulic oil in the adaptive cylinder 19 through a connecting pipeline into the other three adaptive telescopic cylinders 19; because the oil has viscosity and has certain resistance when entering the connecting pipeline with a smaller cross section from the rod cavity with a larger cross section, while the oil is squeezed into the other three adaptive telescopic cylinders, an anti-pressing force is generated on the blank at this place, to squeeze excess aluminum solution to other places; because the pressing force is a flexible force, no excessive impact force is generated on the blank. Compared with the directly acting molding pressure, the pressing force has the characteristics of flexibility and changeability. Because the four adaptive telescopic cylinders are communicated, the balance cylinder group formed by the four communicated adaptive cylinders always adaptively adjusts the indenter 17 while the balance rod 18 conducts slow compression molding. The structural design of the balance cylinder group can also absorb the internal stress of the blank. The slow pressing action of the balance rod 18 and the balance cylinder group action formed by the four communicated adaptive cylinders jointly act on the indenter 17 to act on the blanks; and an adaptive molding action is performed on the blanks.
[0079] Preferably, the speed of the balance rod 18 satisfies: the oil pressure in the balance rod 18 reaches 10 MPa, and the entire adaptive molding action process lasts for more than 60s.
[0080] VI Adjusting levelness of the indenter 17 of the upper mold 5:
[0081] Enabling the solenoid valves among the adaptive telescopic cylinders 19 to acts; cutting off the communication among the adaptive telescopic cylinders 19; then choosing to fill the corresponding adaptive cylinders 19 according to the state of the indenter 17 detected by a level meter, thereby adjusting the levelness of the indenter 17 until the levelness detected by the level meter reaches a standard; and stopping the action for 60S;
[0082] VII Cooling:
[0083] After reaching the time, driving the molding cylinder 4 to contract and driving the indenter 17 to move up; when a lower surface of the indenter 17 is located between a cold air pipe 12 and the vacuum pipe 11, outputting cold air from the cold air pipe for rapid cooling; and stopping cooling when the temperature reaches 60°C;
[0084] VIII Taking out the blanks:
[0085] Taking out the carbon fiber reinforced composite material after compression molding to obtain the processed carbon fiber composite material.
[0086] Because the adaptive molding action is innovatively adopted during the processing for the carbon fiber reinforced composite material processed through the above molding process, while the carbon fiber reinforced composite material blank is molded, the indenter can adapt to the surface of the blank to make corresponding actions. The entire molding process can dynamically adjust the indenter to adapt to the changing blank surface. After the actions, the internal stress of the carbon fiber cloth layers is absorbed and the aluminum solution between the layers is sufficiently uniformly impregnated, so that the mechanical property of the carbon fiber reinforced composite material after the molding is significantly improved.
[0087] The above only describes preferred embodiments of the present invention and is not intended to limit the present invention. Any simple amendment, change and equivalent structural change to the above embodiments according to the technical essence of the present invention shall still belong to the protection scope of the technical solutions of the present invention.
Claims (4)
1. A compression molding process of carbon fiber reinforced composite
material, comprising the following steps:
(I) placing blanks:
according to an alternating sequence of a carbon fiber cloth layer, an aluminum
powder layer and a carbon fiber cloth layer, placing the blanks into a lower mold
cavity of a lower mold of a hot press molding device;
(II) semi-mold closing:
driving a molding cylinder of the hot press molding device to act so that an
indenter of the upper mold quickly reaches the lower mold cavity and comes into
contact with the lower mold cavity to form a semi-mold closing state;
(III) semi-mold closing environment processing:
turning on a vacuum pump to vacuum a space in the lower mold cavity;
simultaneously, starting a heating resistance wire A and a heating resistance wire B in
the indenter and the lower mold for heating, so that a negative pressure in the lower
mold cavity reaches a certain value and then the vacuum pump is turned off;
simultaneously, enabling the heating resistance wire A and the heating resistance wire
B to continue to heat until the melting temperature of aluminum powder reaches
660°C ±3C; and stopping heating;
(IV) continuing mold closing:
starting the molding cylinder to act again, so that the indenter continues to
descend; and closing the molding cylinder when the indenter comes into contact with
a highest point H of blank deformation;
(V) adaptive molding action:
starting a balance rod to make an extension action; driving the indenter to
continue to descend slowly; disconnecting four adaptive telescopic cylinders evenly
arranged around the balance rod from a hydraulic pump; communicating oil paths
between the rodless cavities of the adaptive telescopic cylinders to form a dynamic
balance cylinder group, so that the indenter which freely rotates around the balance rod is controlled by the dynamic balance cylinder group to act; when the indenter touches the highest point H of blank deformation, generating, by the blank at H, an obstructing force on the adaptive telescopic cylinder located here, thereby squeezing hydraulic oil in the adaptive cylinder through a connecting pipeline into the other three adaptive telescopic cylinders; while the oil is squeezed into the other three adaptive telescopic cylinders, generating, by the oil, an anti-pressing force on the blank at this place, to squeeze excess aluminum solution to other places; enabling the slow pressing action of the balance rod and the balance cylinder group action formed by the four communicated adaptive cylinders to jointly act on the indenter to act on the blanks; and performing an adaptive molding action on the blanks;
(VI) adjusting levelness of the indenter of the upper mold:
after the adaptive molding action is completed, stopping extending by the
balance rod so that a solenoid valve among the adaptive telescopic cylinders acts;
cutting off the communication among the adaptive telescopic cylinders; then choosing
to fill the corresponding adaptive cylinders according to the state of the indenter
detected by a level meter installed on the upper end of the indenter, thereby adjusting
the levelness of the indenter until the levelness detected by the level meter reaches a
standard; and stopping the action for 60s;
(VII) cooling:
after reaching a predetermined time, driving the molding cylinder to contract and
driving the indenter to move up; when a lower surface of the indenter is located
between a cold air pipe and the vacuum pipe, outputting cold air from the cold air
pipe for rapid cooling; and stopping cooling when the temperature reaches 60°C;
(VIII) taking out the blanks:
taking out the carbon fiber reinforced composite material after compression
molding to obtain the processed carbon fiber composite material.
2. The compression molding process of carbon fiber reinforced composite
material according to claim 1, wherein the certain value in the step (III) enables a
vacuum degree in the lower mold cavity to be below 1 KPa.
3. The compression molding process of carbon fiber reinforced composite
material according to claim 1, wherein in the step (V), while the balance rod conducts
slow molding, the balance cylinder group formed by the four communicated adaptive
cylinders always adjusts the indenter adaptively; and the structural design of the
balance cylinder group can also absorb pressure in the blanks.
4. The compression molding process of carbon fiber reinforced composite
material according to claim 1, wherein in the step (V), when starting the balance rod
to make the extension action and driving the indenter to continue to descend slowly,
the speed of the balance rod satisfies: the oil pressure in the balance rod reaches
1OMPa, and the entire adaptive molding action process continues for more than 60s.
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| CN201911015705.X | 2019-10-24 | ||
| CN201911015705.XA CN110920096A (en) | 2019-10-24 | 2019-10-24 | Compression molding process of carbon fiber reinforced composite material |
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| AU2020100834A4 true AU2020100834A4 (en) | 2020-07-02 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114347346A (en) * | 2022-02-11 | 2022-04-15 | 抚顺琥珀泉艺术品有限公司 | Amber tea cup automatic production device and control method |
| US11529772B2 (en) | 2020-09-30 | 2022-12-20 | Shaanxi University Of Science & Technology | Apparatus and method for efficiently preparing multi-directional continuous fiber-reinforced composite material |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113084158A (en) * | 2021-03-30 | 2021-07-09 | 段娜 | Forming method of silver powder sinter cake and powder sinter device |
| CN115056511B (en) * | 2022-05-20 | 2024-02-13 | 中国兵器科学研究院宁波分院 | Casting device for oriented wire reinforced composite material |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2834888Y (en) * | 2005-11-21 | 2006-11-08 | 天津市天锻压力机有限公司 | Hydraulic press with four spot synchronous balance guiding device on pressure head |
| CN101811375B (en) * | 2009-10-29 | 2014-12-31 | 余姚市捷宇机械有限公司 | Full floating self-balanced pressure head for rubbish compressor |
| CN102717518B (en) * | 2012-06-25 | 2015-03-04 | 江苏大学 | Integrated manufacture and testing device and testing method for carbon fiber composite material |
| BR112017015847B1 (en) * | 2015-02-27 | 2022-05-24 | Huntsman Advanced Materials Licensing (Switzerland) Gmbh | Process for preparing a fiber-reinforced composite article |
| CN207972342U (en) * | 2018-02-28 | 2018-10-16 | 爱尔铃克铃尔汽车部件（中国）有限公司 | A kind of float top board mechanism being suitable for high-accuracy injection molding and integrating device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11529772B2 (en) | 2020-09-30 | 2022-12-20 | Shaanxi University Of Science & Technology | Apparatus and method for efficiently preparing multi-directional continuous fiber-reinforced composite material |
| CN114347346A (en) * | 2022-02-11 | 2022-04-15 | 抚顺琥珀泉艺术品有限公司 | Amber tea cup automatic production device and control method |
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