TWI814253B - A method of reshaping a carbon fiber product - Google Patents

Abstract

The present invention reveals a method of reshaping a carbon fiber product with the steps comprising of: forming a continuous carbon fiber product by apply a series process of heating, pressing, cooling and solidification on a continuous carbon fiber prepreg which impregnated in a thermoplastic resin, wherein, the continuous carbon fiber product can be made with a solid tube, a sheet or a hollow tube shape; providing a compress and a heating temperature to an area of the continuous carbon fiber product, and the thermoplastic resin of the area can be melted by the heating and the area can be bend to from a curve shape.

Description

Secondary processing and forming method of carbon fiber products

A processing and forming method, especially a secondary processing and forming method of carbon fiber products.

Carbon fiber has become a popular application material in various fields because of its high temperature resistance, high tensile strength, corrosion resistance, impact resistance, electrical and thermal conductivity, small size and light weight. In order to improve the rigidity and strength of a carbon fiber product, most current manufacturing processes use multiple layers of carbon fiber material impregnated with a thermosetting resin, and through a pressure and a heating temperature given by a mold or a hot press, the carbon fiber material is Multiple layers of carbon fiber materials are cured and formed.

However, if the above-mentioned process is to produce strip-shaped or tubular carbon fiber products with a curved structure, the mold preparation must be designed separately to match the curved structure. Not only is the cost high, but the finished product cannot achieve the desired appearance level. As well as structural strength, not to mention the complexity of the mold design when making tubular carbon fiber products with curved structures is not practical for mass production. This limits the scope and field of carbon fiber applications. In view of this, developing a method that can produce the carbon fiber products with a curved structure is a problem that relevant industries are eager to overcome.

In order to develop a method that can produce the carbon fiber product with a curved structure, the present invention provides a secondary processing and forming method of the carbon fiber product, the steps of which include: A continuous carbon fiber material impregnated in a thermoplastic resin is heated, pressed, and cooled to solidify to form a continuous carbon fiber product; Applying a pressure and a heating temperature to an area to be bent of the continuous carbon fiber product causes the thermoplastic resin in the area to be bent to melt and soften, and the pressure should be applied to bend the product to form a curved structure.

Wherein, the continuous carbon fiber product is in the shape of a solid column, a plate or a hollow tube.

Wherein, the continuous carbon fiber product uses a winding or pultrusion process to form the solid columnar continuous carbon fiber product.

The continuous carbon fiber material is laid on a mold or wrapped around a mandrel. After heating and pressing and removing the mold and the mandrel, the continuous carbon fiber product is formed corresponding to the mold or the mandrel.

Among them, the thermoplastic resin can be selected from polyoxymethylene (POM), acrylonitrile-butadiene-styrene (ABS), polyphenylene sulfide (PPS), polysulfone (PSU), polyethersulfone (PES), Polyetheretherketone (PEEK), aromatic polyester liquid crystal polymer (LCP), polyetherimide (PEI), polyamideimide (PAI), polyacetal (POM), nylon (PA), Polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphenylene ether (PPE), styrene acrylic glue acrylonitrile (ASA), polyphenylene ether Ethylene (PS), polymethyl methacrylate (PMMA), styrene copolymer (MS), cellulose acetate (CA), thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), styrenic elastomer (TPS), nylon 12, elastomer (PAE), polytetrafluoroethylene (PTFE), vinylon (vinylon), polypropylene (PP), polyethylene (PE), ethylene/vinyl acetate copolymer (EVA) or A type of polyvinyl chloride (PVC)

Further, the heating temperature is provided on the circumferential surface of the bending area of the continuous carbon fiber product, so that the bending area can be locally annularly heated; two clamping arms are clamped at both ends of the bending area and move At least one clamping arm allows the continuous carbon fiber product to form the curved structure, and is finally cooled and solidified.

Further, the bending area of the continuous carbon fiber product is placed between a mold and a pressing element, and the heating temperature is given to the continuous carbon fiber product at the same time, wherein the mold faces one side of the continuous carbon fiber product. It includes a curvature; the pressing element gives the pressure to the area to be bent toward the mold, so that the area to be bent leans toward the mold and concavely forms the curved structure according to the arc, and is finally cooled and solidified.

Further, when the hollow tubular continuous carbon fiber product is bent, a bending mandrel is placed adjacent to the area to be bent.

Further, a reinforcing structure is formed on one surface of the bent continuous carbon fiber product.

Further, heating and pressure are used to make the continuous carbon fiber material adhere to the continuous carbon fiber product, so that the thickness of at least a part of the tube wall of the continuous carbon fiber product is increased to form the reinforcing structure.

Further, the reinforcing structure is a silicone or a rubber formed on the surface of the continuous carbon fiber product.

The secondary processing and forming method of carbon fiber products provided by the present invention has low cost and simple steps. Since the continuous carbon fiber product is made of the carbon fiber prepreg sheet impregnated with the thermoplastic resin, the continuous carbon fiber product can be processed The reprocessing process also overcomes the need to make costly molds one by one for strip-shaped, plate-shaped or tube-shaped carbon fiber products with curved structures in the traditional process, and achieves the practicality of mass production, which helps to expand the carbon fiber production and application.

Please refer to Figure 1, which is a secondary processing and forming method of carbon fiber products provided by the present invention. The steps include:

Step S1, the first forming of a continuous carbon fiber product: a plurality of continuous carbon fiber materials are sequentially heated, pressurized, and cooled and solidified to form a continuous carbon fiber product. The shape of the continuous carbon fiber product is not limited. The continuous carbon fiber It is a solid column, a plate or a hollow tube. The manufacturing methods of heating, pressing, cooling and solidifying include pultrusion, continuous extrusion, etc. The continuous carbon fiber material can be formed by impregnating a carbon fiber fabric with a thermoplastic resin, and the thermoplastic resin can be selected from polyoxymethylene (POM), acrylonitrile-butadiene-styrene (ABS), Polyphenylene sulfide (PPS), polystyrene (PSU), polyether sulfide (PES), polyetheretherketone (PEEK), aromatic polyester liquid crystal polymer (LCP), polyetherimide (PEI), polyether Amidoimide (PAI), polyacetal (POM), nylon (PA), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET) ), polyphenylene ether (PPE), styrene acrylic glue acrylonitrile (ASA), polystyrene (PS), polymethyl methacrylate (PMMA), styrene copolymer (MS), cellulose acetate (CA) , thermoplastic polyurethane (TPU), thermoplastic polyester elastomer (TPEE), styrenic elastomer (TPS), nylon 12, elastomer (PAE), polytetrafluoroethylene (PTFE), vinylon (vinylon), polypropylene (PP), polyethylene (PE), ethylene/vinyl acetate copolymer (EVA) and polyvinyl chloride (PVC).

When the continuous carbon fiber product is in the shape of a continuous plate, it can be formed by a rolling process so that the continuous carbon fiber material forms the continuous carbon fiber product.

When the continuous carbon fiber product is in a solid columnar shape, it can be formed using a winding or pultrusion process so that the continuous carbon fiber material forms the continuous carbon fiber product.

Furthermore, when the continuous carbon fiber product is in the shape of a hollow tube, the continuous carbon fiber material can be laid in a mold space formed in a mold or wrapped around a mandrel, and heated and pressurized and combined with the mold space. The mold and the mandrel are separated, so that the continuous carbon fiber product is formed corresponding to the mold or the mandrel.

Step S2, secondary processing to form a curved structure: applying a pressing force and a heating temperature locally to an area to be bent on the surface of the continuous carbon fiber product, so that the continuous carbon fiber product forms the curved structure, wherein the heating temperature can cause the continuous carbon fiber product to form the curved structure. The thermoplastic resin in at least one area of the surface of the continuous carbon fiber product is melted and softened, so that the continuous carbon fiber product can be bent and formed in response to the pressure. The heating temperature can be induction heating or infrared heating. In this embodiment, a pipe bending machine or a plate bending machine can be used to provide the simultaneous shift of the pressing force and the heating temperature, and bend the continuous carbon fiber product.

In the first embodiment of the present invention, the pipe bending machine provides the heating temperature on a circumferential surface of the area to be bent of the columnar or tubular continuous carbon fiber product, so that the area to be bent can be locally heated. At the same time, the pipe bending machine provides two clamping arms for clamping at both ends of the bending area. When the heating temperature rises to the plastic state, at least one of the clamping arms is moved so that the continuous carbon fiber product The curved structure is formed and finally cooled and solidified.

When the continuous carbon fiber product is in a tubular shape, a bending mandrel can be placed in the continuous carbon fiber product adjacent to both ends of the bending area to ensure that the continuous carbon fiber product can form the bending structure in the bending area, or it can Prevent the tubular continuous carbon fiber product from deforming when bending. More preferably, the clamping arm position corresponds to the bending mandrel. In this way, the clamping arm can effectively prevent the continuous carbon fiber product from deforming when bending. The continuous carbon fiber product is damaged and deformed.

In the second embodiment of the present invention, when the continuous carbon fiber product is in a plate shape, the continuous carbon fiber product is placed in a bending machine so that the area to be bent of the continuous carbon fiber product can be positioned on the bending machine Between a mold and a pressing element, the heating temperature is given to the area to be bent at the same time, wherein one side of the mold toward the continuous carbon fiber includes a curvature. The pressing element of the bending machine gives the pressure to the bending area toward the mold, so that the bending area abuts against the mold and concavely forms the curved structure according to the arc, and is finally cooled and solidified.

Step S3, forming a reinforcing structure: further, the bent continuous carbon fiber product can be reinforced by heating and pressing the continuous carbon fiber material. For example, the continuous carbon fiber product is attached to at least part of the surface of the continuous carbon fiber product along the length direction with heat and pressure to form the reinforcing structure, so that the thickness of the tube wall of at least part of the continuous carbon fiber product is increased, thereby strengthening the overall structure of the continuous carbon fiber product. intensity.

Furthermore, the reinforcing structure is not limited to being attached to the continuous carbon fiber product. The reinforcing structure may be a silicone or a rubber formed on the surface of the bent continuous carbon fiber product, wherein the silicone or the rubber The rubber can be formed on the surface of the continuous carbon fiber product by coating or being immersed in a tank to enhance the bending resistance of the continuous carbon fiber product.

In another embodiment provided by the present invention, a fiber winding technology can also be used to form the reinforcing structure on the surface of the continuous carbon fiber product. The fiber winding technology can wrap a carbon fiber pre-impregnated in the thermoplastic resin around the outer periphery of the continuous carbon fiber product and form a structure with multiple layers by continuously providing a winding temperature and a coating pressure during winding. The application of the fiber allows the carbon fibers between each layer to be welded into one body, and finally increases the overall structural strength of the continuous carbon fiber product after cooling and solidification.

The secondary processing and forming method of carbon fiber products provided by the present invention provides a brand-new manufacturing method of thermoplastic carbon fiber materials. The manufacturing of carbon fiber products is mainly divided into two stages. In the first stage, semi-finished products are continuously manufactured in large quantities and then completed in specific areas according to needs. The workpiece is finally formed, which can greatly reduce the production cost and the steps are simple and can be automated; the method of the present invention allows the continuous carbon fiber material to be reprocessed, overcoming the problem of strips, plates or tubes with curved structures in the traditional process. The carbon fiber products need to be produced one by one with different molds, which leads to high cost. However, it is practical to produce them in large quantities, which helps to expand the production and application of carbon fiber.

without

Figure 1 is a schematic diagram of the steps of the preferred embodiment of the present invention.

Claims (5)

A method for secondary processing and forming of carbon fiber products, the steps of which include: forming a continuous carbon fiber product by heating, pressurizing, and cooling and solidifying a plate-shaped continuous carbon fiber material impregnated in a thermoplastic resin; A pressure and a heating temperature are given to a region to be bent, so that the thermoplastic resin in the region to be bent melts and softens, and is bent according to the pressure to form a curved structure; and a heating and pressure is used to make the bent structure Another continuous carbon fiber material is attached to one surface of the continuous carbon fiber product, so that the thickness of at least a part of the continuous carbon fiber product is increased to form a reinforcing structure. The secondary processing and forming method of carbon fiber products as described in claim 2, wherein: the heating temperature is provided on a circumferential surface of the area to be bent of the continuous carbon fiber product, so that the area to be bent can be locally heated; two clamps The holding arms are clamped at both ends of the area to be bent, and at least one of the holding arms is moved so that the continuous carbon fiber product forms the curved structure, and is finally cooled and solidified. The secondary processing and forming method of carbon fiber products as described in claim 2, wherein: the bending area of the continuous carbon fiber product is placed between a mold and a pressing element, and the heating temperature is given to the continuous carbon fiber product at the same time , wherein one side of the mold toward the continuous carbon fiber product includes an arc; the pressing element gives the area to be bent the pressure toward the mold, so that the area to be bent leans toward the mold and is concavely formed according to the arc. The structure is bent and finally cooled to solidify. The secondary processing and forming method of carbon fiber products as described in any one of claims 1 to 3, uses a fiber winding technology to wind a carbon fiber pre-impregnated in the thermoplastic resin around the outer periphery of the continuous carbon fiber product, and forms There are multiple layers of this reinforcing structure. As for the secondary processing and forming method of carbon fiber products described in claim 4, the thermoplastic resin can be selected from the group consisting of polyoxymethylene (POM), acrylonitrile-butadiene-styrene (ABS), polyphenylene sulfide (PPS), Polyethylene (PSU), polyetheretherketone (PES), polyetheretherketone (PEEK), aromatic polyester liquid crystal polymer (LCP), polyetherimide (PEI), polyamideimide (PAI) , polyacetal (POM), nylon (PA), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphenylene ether (PPE) , styrene acrylic glue acrylonitrile (ASA), polystyrene (PS), polymethyl methacrylate (PMMA), styrene copolymer (MS), cellulose acetate (CA), thermoplastic polyurethane (TPU), thermoplastic Polyester elastomer (TPEE), styrenic elastomer (TPS), nylon 12, elastomer (PAE), polytetrafluoroethylene (PTFE), vinylon (vinylon), polypropylene (PP), polyethylene (PE) ), ethylene/vinyl acetate copolymer (EVA) and polyvinyl chloride (PVC).