A carbon fiber node fusion type compression molding process

Abstract

The application discloses a kind of carbon fiber node fusion formula moulding forming process, and plain weave carbon cloth is immersed in epoxy resin.Prewarm to 50~60℃ in mould, and smears release agent on forming surface.Multiple layers of plain weave carbon cloth are first laid on the forming surface in mould, then the node joint to be processed is placed in the groove of the forming surface corresponding to the laid plain weave carbon cloth.The node joint is composed of multiple parts.Multiple layers of plain weave carbon cloth are then laid on the node joint to be processed, and the multiple layers of plain weave carbon cloth are trimmed according to the size of the node joint to be processed.A male die is inserted into the interior of the node joint to be processed.The mould fixes and pressurizes the entire node joint to be processed, and the mould is sent into a curing oven.The node joint in the mould is cured in the curing oven at an environment of 120℃ for 2 hours.After that, the temperature in the curing oven is raised to 170℃, and curing is continued for 4 hours.The curing oven is naturally cooled to room temperature, the node joint is demoulded, and the processed node joint is surface treated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of civil engineering light composite structure forming, in particular to a carbon fiber node fusion type mold pressing forming process. BACKGROUND

[0002] The traditional carbon fiber radial beam usually adopts two forming methods. The carbon fiber straight pipe and the metal joint are bonded with each other by structural glue (adhesive); another method adopts carbon fiber skin forming respectively, and then is bonded and solidified with the honeycomb core sandwich through the glue film secondary bonding and solidification forming. The two forming methods both adopt secondary forming, which greatly reduces the stiffness of the carbon fiber radial beam and the connection strength between the metal part and the carbon fiber pipe.

[0003] The truss nodes in the prior art are mostly bonded with two models. Although this bonding forming method is very simple, the strength is very low. And in the subsequent pressing process, it is very likely to produce gaps and buckling. This leads to a low yield rate and unnecessary material waste. When multiple connecting pipes are connected at one point, multiple stress concentrations at one point can easily damage the node. SUMMARY

[0004] The present application provides a carbon fiber node fusion type mold pressing forming process, the node joint is composed of multiple parts, which solves the problem of low node strength and loose connection with the connecting pipe caused by the secondary forming or two model bonding in the prior art.

[0005] The technical scheme adopted by the present application is as follows:

[0006] The present application provides a carbon fiber node fusion type mold pressing forming process, which comprises the following steps:

[0007] Step one: immerse the plain carbon cloth in epoxy resin;

[0008] Step two: preheat the forming surface in the mold to 50-60 DEG C, and apply release agent on the forming surface;

[0009] Step three: lay multiple layers of plain carbon cloth on the forming surface in the mold, then combine the multiple parts of the node joint to be processed, and place the node joint in the corresponding forming surface groove with the plain carbon cloth laid thereon;

[0010] Step four: lay multiple layers of plain carbon cloth on the node joint to be processed, and trim the multiple layers of plain carbon cloth according to the size of the node joint to be processed;

[0011] Step five: insert the male mold into the node joint to be processed;

[0012] Step six: the mold fixes and pressurizes the whole node joint to be processed, and sends the mold into the curing oven; the node joint in the mold is cured for 2 hours under the environment of 120℃ in the curing oven; then the temperature in the curing oven is raised to 170℃, and the node joint in the mold is cured for 4 hours;

[0013] Step seven: the curing oven is naturally cooled to room temperature, the node joint is demolded, and the processed node joint is surface treated.

[0014] Preferably, the mold comprises a first female mold, a second female mold, a third female mold, a fourth female mold, a baffle and a mold base;

[0015] The mold base is provided with a first positioning head and a second positioning head; the first positioning head is inserted into the bottom of the second female mold; the second positioning head is inserted into the bottom of the baffle; the first female mold is connected to the mold base through fastening bolts; the third female mold and the fourth female mold are respectively buckled on the two sides of the second female mold.

[0016] Preferably, the second female mold comprises two abutting first splicing blocks and second splicing blocks.

[0017] Preferably, the node joint comprises a first splicing block, a second splicing block, a third splicing block, a fourth splicing block and a fifth splicing block.

[0018] One side of the fifth splicing block is connected to the fourth splicing block; the other side of the fifth splicing block is connected to the second splicing block; the other side of the second splicing block is connected to the first splicing block and the third splicing block; the side surface of the fourth splicing block is connected to the first splicing block and the third splicing block; the first splicing block is connected to the third splicing block.

[0019] Preferably, the node joint comprises a plurality of splicing pipes.

[0020] Preferably, the thickness of 1 layer of plain carbon cloth is 0.3mm.

[0021] Preferably, 4 layers of plain carbon cloth are laid on the forming surface in the mold; 4 layers of plain carbon cloth are laid on the node joint.

[0022] Preferably, the mold and the male mold are made of stainless steel.

[0023] Beneficial effects:

[0024] 1. The node joint comprises a plurality of parts, which can avoid damage caused by multi-directional stress concentration in one point, and better fit the surface of the connecting pipe, thereby increasing the fitting degree.

[0025] 2. The mold includes a first female mold, a second female mold, a third female mold, a fourth female mold, a baffle, and a mold base. Multiple molds apply forces in multiple directions to the joint to be processed, thereby improving the pressure curing effect.

[0026] 3. The second female mold consists of two parts: a first splicing block and a second splicing block. This design allows for quick and easy demolding of the cured joint. Attached Figure Description

[0027] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This application provides a schematic diagram of the main view of a node joint in a carbon fiber node fusion molding process.

[0029] Figure 2 An equiaxed side view of the node joint in a carbon fiber node fusion molding process provided in this application;

[0030] Figure 3 A schematic diagram of a mold used in a carbon fiber node fusion compression molding process provided in this application;

[0031] Figure 4 An isometric side view of the second female mold in a carbon fiber node fusion compression molding process provided in this application;

[0032] Figure 5 A schematic diagram of the third female mold in a carbon fiber node fusion compression molding process provided in this application;

[0033] Figure 6 A schematic diagram of the fourth female mold in a carbon fiber node fusion compression molding process provided in this application;

[0034] Figure 7 A schematic diagram of the first female mold in a carbon fiber node fusion compression molding process provided in this application;

[0035] Figure 8 A schematic diagram of the mold base in a carbon fiber node fusion compression molding process provided in this application;

[0036] Figure 9 A flowchart of a carbon fiber node fusion compression molding process provided in this application.

[0037] [Explanation of Labels in the Attached Image]

[0038] 1-Node connector, 11-First splicing block, 12-Second splicing block, 13-Third splicing block, 14-Fourth splicing block, 15-Fifth splicing block;

[0039] 2-Mold, 21-First female mold, 22-Second female mold, 221-First splicing block, 222-Second splicing block, 23-Third female mold, 24-Fourth female mold, 25-Baffle, 26-Mold base, 261-First positioning head, 262-Second positioning head

[0040] 3-Positive mold. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0042] Example 1:

[0043] This application provides a carbon fiber node fusion compression molding process, including the following steps:

[0044] Step 1: Impregnate the plain-weave carbon cloth with epoxy resin. The plain-weave carbon cloth used is T700-3K carbon cloth, with a thickness of 0.3mm. The epoxy resin used is E51 epoxy resin, with the addition of low molecular weight polyamide and SiO2.

[0045] Step 2: Preheat the molding surface inside mold 2 to 50℃~60℃, and evenly apply mold release agent to the molding surface. Before performing Step 2, the molding surface of mold 2 can be cleaned with acetone. Acetone can reduce or even remove residues on the molding surface that could affect subsequent work.

[0046] Step 3: First, lay the multi-layer plain carbon cloth on the molding surface of the mold 2, and manually press it to make the plain carbon cloth adhere tightly to the molding surface of the mold 2. Then, preliminarily assemble the multiple parts of the node joint 1 to be processed together with epoxy resin. Next, grind the ends of the node joint 1 to be processed and place it in the groove of the molding surface on which the plain carbon cloth is laid. Align the position and press the node joint 1 and the plain carbon cloth firmly downwards.

[0047] like Figures 1-2 As shown, the node connector 1 includes a first splicing block 11, a second splicing block 12, a third splicing block 13, a fourth splicing block 14, and a fifth splicing block 15;

[0048] The fifth splicing block 15 is connected to the fourth splicing block 14 on one side via epoxy resin; the fifth splicing block 15 is connected to the second splicing block 12 on the other side via epoxy resin; the second splicing block 12 is connected to the first splicing block 11 and the third splicing block 13 on the other side via epoxy resin; the fourth splicing block 14 is connected to the first splicing block 11 and the third splicing block 13 on one side via epoxy resin; the first splicing block 11 is connected to the third splicing block 13 via epoxy resin.

[0049] Furthermore, the mold 2 is as follows Figures 3-8 The mold includes a first female mold 21, a second female mold 22, a third female mold 23, a fourth female mold 24, a baffle 25, and a mold base 26.

[0050] The first female mold 21, the second female mold 22, the third female mold 23, and the fourth female mold 24 are all provided with mold grooves.

[0051] The mold base 26 is provided with a first positioning head 261 and a second positioning head 262; the first positioning head 261 is inserted into the bottom of the second female mold 22; the second positioning head 262 is inserted into the bottom of the baffle 25; the first female mold 21 is connected to the mold base 26 by fastening bolts; the third female mold 23 and the fourth female mold 24 are respectively fastened to both sides of the second female mold 22.

[0052] Furthermore, the second female mold 22 includes two abutting first splicing blocks 221 and a second splicing block 222. This design facilitates subsequent demolding of the finished product.

[0053] Step 4: Lay multiple layers of plain carbon fiber cloth on the node joint 1 to be processed, completely covering the node joint 1, and trim the multiple layers of plain carbon fiber cloth according to the size of the node joint 1 to be processed; manually press the plain carbon fiber cloth to the node joint 1.

[0054] In the first embodiment of this application, the multi-layer plain-weave carbon cloth used in steps three and four is four layers. Four layers of plain-weave carbon cloth improve stability and load-bearing capacity while minimizing excessive thickness.

[0055] Step 5: Insert the male mold 3 into the node joint 1 to be processed; to prevent the node joint 1 from splitting due to the compression of the mold 2.

[0056] Step Six: Place the second female mold 22 entirely onto the first positioning head 261 on the mold base 26. Press the third female mold 23 and the fourth female mold 24 onto the node joint 1 according to their spatial alignment, ensuring a tight fit between the third female mold 23 and the fourth female mold 24 and the node joint 1. Place baffles 25 on the second positioning heads 262 near both ends on the top surface of the mold base 26. The baffles 25 are used to position and protect the second female mold 22, the third female mold 23, and the fourth female mold 24. Then, fasten the first female mold 21 onto the mold base 26 and the node joint 1. Install bolts between the first female mold 21 and the mold base 26, and apply pressure by tightening the bolts. Place the mold 2 into the curing oven; the node joint 1 in the mold 2 is cured at 120°C for 2 hours in the curing oven; then the temperature in the curing oven is increased to 170°C, and the node joint 1 in the mold 2 is cured for 4 hours.

[0057] Step 7: After the curing oven has cooled to room temperature naturally, demold the node joint 1 and perform surface treatment on the processed node joint 1.

[0058] Furthermore, both the mold 2 and the male mold 3 are made of stainless steel.

[0059] In the first embodiment, the positions of the first female mold 21, the second female mold 22, the third female mold 23, and the fourth female mold 24 correspond to the positions of the first splicing block 11, the second splicing block 12, the third splicing block 13, the fourth splicing block 14, and the fifth splicing block 15.

[0060] The second female mold 22 corresponds to the first splicing block 11 and the third splicing block 13; the third female mold 23 corresponds to the second splicing block 12; the fourth female mold 24 corresponds to the fourth splicing block 14; and the first female mold 21 corresponds to the fifth splicing block 15.

[0061] During pressure curing, the first female mold 21, the second female mold 22, the third female mold 23, and the fourth female mold 24 can apply forces in different directions to the entire joint 1, and can also apply pressure to the first splicing block 11, the second splicing block 12, the third splicing block 13, the fourth splicing block 14, and the fifth splicing block 15 in separate zones. This avoids the problem of warping and misfitting during pressure curing, and also makes the heating and pressure application of the joint 1 more uniform, resulting in better quality of the finished product.

[0062] Example 2:

[0063] Unlike the features described above, the node joint 1 includes multiple splicing pipes. All other features are the same.

[0064] The node joint 1 in this embodiment is composed of multiple independent sleeves connected together. The male mold 3 is inserted and placed into the mold 2. Then, it is heated and pressurized for curing, softening the material of the node joint 1, and then reassembled and shaped to finally obtain the finished node joint 1.

[0065] In both Embodiments 1 and 2 of this application, the heat curing process involves softening the joint 1 to ensure thorough bonding of all parts, followed by further fixation using epoxy resin-impregnated plain-weave carbon cloth, ultimately resulting in the finished product. This application features a simple process, stable product quality, and finished products with excellent geometric precision and mechanical properties.

[0066] This method is more convenient during the preparation period before production and reduces the workload of staff.

[0067] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A carbon fiber node fusion molding process, characterized in that, Includes the following steps: Step 1: Impregnate the plain-weave carbon cloth with epoxy resin; Step 2: Preheat the molding surface inside the mold (2) to 50℃~60℃, and apply a release agent to the molding surface; Step 3: First, lay the multi-layer plain carbon cloth on the molding surface in the mold (2), then combine the multiple parts of the node joint (1) to be processed together, and place the node joint (1) in the groove of the molding surface on which the plain carbon cloth is laid. Step 4: Lay multiple layers of plain carbon cloth on the node joint (1) to be processed, and trim the multiple layers of plain carbon cloth according to the size of the node joint (1) to be processed. Step 5: Insert the male mold (3) into the node joint (1) to be processed; Step 6: The mold (2) fixes and pressurizes the entire node joint (1) to be processed, and sends the mold (2) into the curing oven; the node joint (1) in the mold (2) is cured in the curing oven at 120°C for 2 hours; then the temperature in the curing oven is raised to 170°C, and the node joint (1) in the mold (2) is cured for 4 hours; Step 7: After the curing oven has cooled to room temperature, demold the node joint (1) and perform surface treatment on the processed node joint (1); The node connector (1) includes a first splicing block (11), a second splicing block (12), a third splicing block (13), a fourth splicing block (14), and a fifth splicing block (15). The fifth splicing block (15) is connected to the fourth splicing block (14) on one side; the fifth splicing block (15) is connected to the second splicing block (12) on the other side; the second splicing block (12) is connected to the first splicing block (11) and the third splicing block (13) on the other side; the fourth splicing block (14) is connected to the first splicing block (11) and the third splicing block (13) on the side; the first splicing block (11) is connected to the third splicing block (13).

2. The carbon fiber node fusion molding process according to claim 1, characterized in that, The mold (2) includes a first female mold (21), a second female mold (22), a third female mold (23), a fourth female mold (24), a baffle (25), and a mold base (26); The mold base (26) is provided with a first positioning head (261) and a second positioning head (262); the first positioning head (261) is inserted into the bottom of the second female mold (22); the second positioning head (262) is inserted into the bottom of the baffle (25); the first female mold (21) is connected to the mold base (26) by fastening bolts; the third female mold (23) and the fourth female mold (24) are respectively fastened to both sides of the second female mold (22).

3. The carbon fiber node fusion molding process according to claim 2, characterized in that, The second female mold (22) includes two abutting first splicing blocks (221) and a second splicing block (222).

4. The carbon fiber node fusion molding process according to claim 1, characterized in that, The node joint (1) includes multiple splicing pipes.

5. The carbon fiber node fusion molding process according to claim 1, characterized in that, The thickness of one layer of plain weave carbon cloth is 0.3mm.

6. The carbon fiber node fusion molding process according to claim 1, characterized in that, Four layers of plain carbon cloth are laid on the molding surface inside the mold (2); four layers of plain carbon cloth are laid on the node joint (1).

7. The carbon fiber node fusion molding process according to claim 1, characterized in that, Both the mold (2) and the male mold (3) are made of stainless steel.

Images