JPS612518A - Method of molding shaped article of plastic composite article - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for molding plastic composite shaped articles consisting of fibers dispersed within a matrix of plastic material.

[Conventional technology]

Composite materials consisting of plastics reinforced with continuous fibers such as carbon fibers and boron fibers are used to produce articles with high strength-to-weight ratios and desirable stiffness and durability. Articles made from such composites are increasingly being used in the aerospace industry. One type of composite consists of fibers dispersed in a thermoplastic material such as polyaromatic polyetheretherketone, known as PEEK. The above PEEK is the product name of Pictrex (Vict).
Imperial Chemical Industries PLC (ImperialChem
ical Industries pie). The other type of composite consists of fiber-reinforced thermoset materials, which are widely used in industries such as the aerospace industry. Composites containing thermoplastic raw materials have advantages over composites containing thermoset plastics. This advantage is that the solidification of plastic materials is reversible;
The solid composite body can be deformed into the desired shape by heating the composite to the deformable temperature of the plastic material, followed by a molding and cooling process. This operation can be repeated, so that articles made from the composite can be repaired and the composite material can be recycled and used.

[Problem that the invention seeks to solve]

The extent to which a fiber-plastic composite body deforms at elevated temperatures essentially depends on the arrangement of the normally non-stretchable fibers in the body. Composite materials are usually manufactured as sheets in the form of laminates of continuous fibers. In the above continuous fiber,
The fibers of the layer are woven together and are impregnated with a silastic material, the individual filaments of the fibers being surrounded in contact by a plastic material. When the sheet is deformed by bending and/or stretching at elevated temperatures, the plastic material flows and assumes the new shape of the sheet, and the fibers also need to conform to the new shape. Incomplete conformability of the fibers can lead to poor molding and/or unsatisfactory mechanical properties of the shaped article. Conventional forming methods caused fiber "curl" during compression after deformation, usually on the concave side of the target, and also caused surface delamination when one fiber layer was moved relative to an adjacent layer. .

In the case of fiber-thermoset polymer composites, problems in producing shaped articles containing continuous fibers are reduced when the thermoset polymer is a low viscosity cured resin. This is because resin-impregnated fibers are flexible, non-rigid intermediates that can be easily accommodated in shaping molds. however,
These methods have the drawbacks of long curing cycles and low production efficiency of the molding equipment. However, if the thermoset polymer is not a low viscosity resin but has a fairly high viscosity and imparts tonality to the intermediate composite material to be molded and cured, it is very important to fully mold the reinforced intermediate thermoset product. . Such a case is one in which the thermosetting material is a solid impregnated into a fiber structure by a solution method, after which the solvent is removed.

Such products are rigid, plate-like materials that cannot be processed in a manner that allows the low viscosity resin-thorn fiber composite to conform to the shape of a mold. The present invention provides a method for forming such a plate-like intermediate product. This method also applies to low viscosity resins.
It has the advantage that it can also be applied to textile intermediate products.

[Means for solving problems]

According to one aspect of the present invention, a method of forming a shaped article of a plastic composite material having fibers dispersed in a matrix of thermoformable material comprises: a body of the composite material; and a metal sheet plastically deformable at high temperatures. are in contact with each other on at least one side of said body and are under a temperature at which the sheet deforms plastically and at a temperature at which the plastic body conforms to the shape of the sheet; A method for molding a plastic composite material is provided, in which the sheet is pressed against a surface of the sheet to plastically deform the sheet to shape the main body. The above sheet is covered by British Patent Nos. 1,387,586 and 1
, 445,181, are preferred.

Thermoformable materials are thermoplastic or thermoset materials. In the case of a thermoplastic polymer matrix, this matrix must be at a temperature that allows it to be plastically deformed. In the case of a thermoset matrix having such a viscosity that the composite object is a rigid rigid body at ambient temperature, temperature will reduce the viscosity of the rigid thermoset matrix and the matrix will undergo deformation pressure applied through the metal sheet. It must be able to flow when it is in use. In the case of a fluid thermoset resin matrix, the body is easily deformable at ambient temperature. In the latter case, the invention has advantages in the curing step.

Although any thermoplastic material can be used as the matrix, the invention is particularly advantageous when using thermostable high B aromatic polymers. Examples of such aromatic molecules include polyarylketones, polyamides, polyesters, dilysulfones, polyethersulfones, polyarylene sulfinodes, thermoplastic polyimides, polyetherimides, and polyamide-imides. Thermosetting resins include epoxy resins and thermostable resins; examples of thermostable resins include vinyl polyester resins, polyimides, especially those derived from bismaleimide, phthalocyanine resins, polystyrylpyridine. , an imide having an acetylene terminal group, and an imide having a nato group as a terminal group.

The method of the present invention is useful in the field when utilized for forming composite bodies in the form of sheets with a thickness of 0.25 to 25 mm. The length and width of the body are determined by the size of the forming or deforming device. 5m x 3m sheets can be produced from commercially available equipment.

Although the method of the invention is particularly useful for forming shaped articles in which the fibers are continuous and extend across the length or width of the sheet, the method is particularly useful for forming shaped articles in which the fibers are short, e.g. It is also useful when the length is 3 mm.

The method described above can be utilized in a variety of ways, with specific examples including British Patent No. 1,461,317 and British Patent Nos.
A molding device such as that described in No. 552,826 can be used.

In a first embodiment, the method described above, when applied to a reinforced body such as a composite plastic sheet containing a laminate of arbitrarily woven, continuously aligned fibers, substantially eliminates the need for deforming the sheet. A shaped article is obtained from a flat composite sheet, which article is curved about at least one axis in the plane of the flat sheet. In this embodiment, the composite sheet is pressed into the female mold or onto the male mold by pressure acting on the metal sheet.

In a second embodiment, the method of the present invention can be used to form strengthen objects from thin-prepreg sheets while simultaneously transforming the laminate of each prepreg sheet into a shaped article. The thin prepreg sheets in this example are stored by stacking the prepreg sheets by selectively orienting the reinforcing fibers to provide quasi-isotropic reinforcement in the plane of the sheet before reinforcing. . Alternatively, the depreg plates can be stored in a woven state to provide one or more woven sheets to be reinforced. Desirable prepreg materials and methods of making such materials are described in EPC Patent Publication No. 56,703. Thermosetting prepreg materials, especially of the plate-like type, can also be used.

In yet another embodiment, the shaped article can be formed into a flat sheet by reinforcing the prepreg material as described in the second embodiment of the invention.

In another aspect, in the case of thermoplastic products, the method of the invention is useful for producing flat sheets with improved reinforcement and surface finish from sheets reinforced between conventional metal plates that do not deform plastically at high temperatures. can also be used. In this method, a plastically deformable metal sheet is used to press and strengthen a flat sheet onto the surface of a hard disc.

In all of these embodiments, at least one sheet of plastically deformable metal is used, and the composite sheet and the laminate of one or more metal sheets are hereinafter referred to as "sand inches." When transforming a body of reinforced composite material into a shaped article with curvature, a single sheet of metal is pressed against the surface of the article at a suitable temperature, during which time the contact between the metal sheet and the body is maintained by a suitable pressure. Retained. This allows the main body to be transformed into a female shape. It is also possible to use two plastically deformable metal sheets, one on one side of the body. When one sheet is not metal, it must be a material that conforms to the shape imparted to the body by plastic deformation of the metal sheet and has adequate thermal stability for the application at the elevated temperatures employed.

If both sheets are plastically deformable metal, there is no need to constantly deform the composite sand inch on the female mold surface. If a female mold is not used, a useful shaped article with a freely blown dome shape can be obtained.

When forming shaped articles having curvature using the method of the present invention, the composite body is held in place by at least one metal sheet to prevent curling of the fibers while conforming the fibers to the new body shape. do. As a result, without compromising the desired mechanical properties of the composite.

A precisely shaped composite body can be obtained.

The body of the plastic composite material is a sheet containing layered fibers arranged in a plane parallel to the metal sheet. The sandwich can be deformed by stretching the metal sheet, and if desired, the metal sheet can be readily plastically deformed at the deformation temperature employed. Preferably, the edges of the composite body are allowed to move freely in a direction parallel to the sheet. Along with the deformation of the sand inch, the fibers of the composite material also deform to conform to the new shape of the object.

The present invention is particularly useful when molding shaped articles having non-uniform thickness that are difficult or impossible to strengthen or deform using rigid flat platens or mating dies. Using a plastically deformable metal sheet, the sheet conforms to and presses against the irregular surface of the object. In this case, the other side of the body is pressed against a hard flat surface or a male or female surface.

The molding method of the present invention can be applied to a flat body of composite material, but it can also be applied to a body of composite material that already has a curved part. When forming the body into a complex shape, particularly when the body has curvature about one or more axes, the extent to which the sandwich is deformed from its flattened state varies considerably depending on the various positions of the sandwich. If the sandwich initially has a suitable curvature, the difference in deformation in that region can be significantly reduced.

The molding method of the present invention can be applied to a single continuous body of composite material, as well as bodies made from laminated thin sheets of composite material. The above molding method is also applicable to composite bodies initially manufactured from separate pieces of fiber-plastic composite material. These pieces are cut and/or bent or folded using the technique of "origami" to form the body into the desired initial shape. This method can be used with a suitably shaped mold to mold the composite body into a somewhat arbitrary shape. For example, a composite tube with a circular, oval or other cross-sectional shape may be prepared by applying a curved sheet of fiber-plastic composite material as a layer to the inner surface of a tubular mold, with an inflatable airtight metal diaphragm that fits the mold. , i.e. zfl
A sheet that can be deformed as a J-son is formed by providing it inside a composite layer. When heat is applied to the thus formed laminate and air pressure is applied inside the parison, the parison expands with plastic deformation and presses the composite material inside the mold to form a tube.

When manufacturing a composite body from one or more pieces, each moon is strengthened together during deformation.

The method of the present invention combines members that are not plastically deformed or strengthened into a composite body while pressing the sheet against the body.
It can also be used for For example, it may be desirable to provide a surface of the shaped composite body with upstanding brackets or webs having flanges that are recessed into the composite body. Such members are housed in slots or grooves suitably formed in the surface of the mold that abuts the compact, extend into the composite body, and are secured within the body during molding of the shaped body.

The pre-strengthened member is fitted into a slot in the mold surface and held under pressure applied by the tool as the shaped body is formed.

Under these circumstances, it is desirable to produce all shaped composite articles having edges that are reliably controlled in shape and position. This is the case, for example, when molding a composite material into a curved sheet with holes of a predetermined size and shape at predetermined locations. Such control is achieved by providing a raised portion on the surface of the deformable sheet, which raised portion is in contact with the opposing surface of the opposing deformable sheet or with the opposing surface of the mold abutting the composite body; As a result, the composite cannot penetrate into the area delimited by the raised portion during the deformation process. Instead of providing a raised portion on the deformable sheet, the raised portion can be provided on the mold surface when the deformable sheet does not separate the composite body from the mold surface. The raised portion forms a hole in the shaped composite body or delimits the outer peripheral edge of the body itself. When the sand inch has deformable sheets on both sides of the composite, the raised portions of one sheet extend through corresponding holes in the opposing sheet.

The temperature at which the sandwich deforms depends on the nature of the plastic material used. In the case of thermoplastic materials, the temperature must be high enough to plastically deform the thermoplastic material and to satisfactorily bond the fibers after deformation. For PEEK, deformation temperatures of 340-420°C are used. However, it is possible to deform the sandwich at temperatures below the melting point of the thermoplastic material. For semi-crystalline thermoplastic materials such as PEEK, the lowest usable temperature is usually determined by the recrystallization behavior of the material.

The sandwich is deformed by a fluid pressure difference, such as a gas pressure, by the application of mechanical pressure, or a combination thereof. When a pressure difference is applied to one side of a sandwich with two metal sheets, but not to the other side, the metal sheet that is furthest from the point of pressure application ensures that the gas trapped within the sandwich is Can be perforated to allow escape.

Alternatively, the space between the two sheets can be evacuated to remove gas. Furthermore, as long as a vacuum is maintained between the two sheets while the sandwich is being deformed (the term vacuum as used here refers to a pressure less than the ambient pressure), this This maintains reinforcement on the plastic-fiber composite in addition to the reinforcement resulting from stretching the metal sheet. After deformation, in the case of thermoplastic materials, the sandwich is cooled and the deformed composite body is "fixed" in the correct shape. In the case of thermoset materials, the sandwich usually needs to be kept at an elevated temperature after the deformation operation in order to fully cure the resin. The deformation pressurization operation is continued after deformation and during at least the first stage of cooling or hardening, so that the body is maintained under pressure during cooling, thereby preventing possible delamination of the composite body during cooling. avoid.

Cooling of the composite body after molding occurs while the molded body is still in the mold or molding machine. Otherwise, the body, still in contact with the sheet or sheets, is removed from the mold or machine while still hot and allowed to cool rapidly. In this case, it is possible to control the cooling rate of the molded composite body by controlling the ambient temperature, and cooling under such control can be utilized to control the mechanical properties of the molded composite body. be able to.

These properties depend, for example, on the relative proportions of crystalline and amorphous materials in the plastic material, which proportions can be adjusted by controlled cooling.

In one possible method of forming a shaped article, the composite material to be formed is placed between two deformable sheets, and these two sheets are mated around the circumference by a rigid air-tight frame, so that the frame and sheet are joined together. to form inclusion bodies. The frame is provided with one or more holes that are connected by conduits to a vacuum source. The sheets and the composite between the seeds are placed in a mold or mold and deformed, while a vacuum is maintained between the sheets. After molding, the encapsulation body is removed from the molding machine or mold and cooled, during which time the vacuum state within the encapsulation body is maintained. In this case, the vacuum conditions have a consolidation effect during the forming and cooling stages.

During deformation of the sandwich, there is usually some degree of slippage between the composite and metal sheets, so a lubricant is applied to the inside surfaces of the sheets to facilitate this sliding. After the sand inch has cooled, the sheet is removed to obtain a shaped article of fiber-plastic composite.

Prior to assembly of the sandwich, a release agent can be applied to the inside surface of the metal sheet to facilitate sheet removal. However, the method of the invention can be applied to the production of shaped fiber-plastic bodies bonded to metal sheets on one or both sides, in which case one or both sheets remain attached to the body after cooling. Become. In this case, an adhesive, rather than a release agent, is applied to the appropriate metal sheet during assembly of the sandwich, allowing for a firm bonding of the shape to the sheet.

The plastic composite to be formed into a certain shape is either in direct contact with the plastically deformable sheet or sheets during deformation, or the composite is made of a material that deforms together with this composite and the deformable sheets. separated by yet another sheet of . This further sheet can be permanently attached to the plastic composite before or during deformation. The further sheet may, for example, consist of an unfilled polymeric film which is used to improve the surface finish of the shaped article or for other purposes. It is also possible to integrate sheets or films of unfilled plastic material into the body of the composite material.

A particular advantage of using the present invention with thermoset materials is that even if the thermoset material is not fully cured,
This means that the deformable sheet or sheets can retain the shape of the deformable body. This is particularly advantageous for low viscosity resin systems. This is because the time required to hold the shaped article in the mold is reduced and the molding equipment can be used more efficiently. Final curing of the shaped article can therefore be performed on the cured metal support in an oven at a suitable temperature.

〔Example〕

Hereinafter, a method for molding a shaped body of a fiber-plastic composite will be described as an example with reference to the accompanying drawings.

In FIG. 1, a sheet of fiber-thermoplastic composite material 1 is sandwiched between sheets 2 and 3 of Supral J superplastic aluminum alloy. The composite material is sold by Inyreal Chemical Industries plc under the trade name APC-1 and consists of a layer of carbon fibers bonded to a matrix of polyaromatic 2-reatheretherketone. Sheets 2 and 3 are sheet 1
, and a coating of lubricant is applied to the inner surfaces of sheets 1 and 2.3. A coating of adhesive or release agent is likewise applied to the inner surfaces of sheet 1 and sheet 2.3, if desired. The edges of the metal sheet 2.3 extend beyond the edges of the sheet 1, the latter edges being free and unconstrained.

For deformation, the sandwich is placed in contact with a forming tool, heated to a temperature above 340° C., and deformed. One example of a forming tool is shown schematically in FIG. When using this tool, the heated planar sandwich is placed in the female mold 4 and its edges are clamped to the edges 5 of the mold by conventional clamping means. Liquid pressure, such as air pressure, is then applied in the direction indicated by the arrows so that the sandwich is conformally deformed to the shape indicated by the continuous line.

The sheet 2 adjacent to the mold surface is perforated to allow the gas present in the sheet 1 to escape, and the mold is also provided with perforations to allow the gas to escape from the spatial region between the sheet 2 and the female mold surface. , a gas vent hole (not shown) is provided. Alternatively, the space area between the non-perforated sheets 2, 3 can be evacuated. To avoid delamination, air pressure is maintained until the sandwich is sufficiently cooled.

Molds can take a variety of shapes to form articles of a variety of shapes. One form of mold for forming a square curve is shown in FIG. The deformation caused by this mold is the second
This is done in the same way as the mold shown.

Another modification method is schematically illustrated in FIGS. 4 and 5. In this case, the sandwich, which has been tightened at the edge 6 and heated to a temperature exceeding 340°C, is "plugged"
Deformed by the mechanical force applied to tool 7, the sandwich inch is deformed as shown in FIG. next,
Air pressure is applied to the opposite side of the sandwich, as indicated by the arrows in FIG. 5, to further deform the sandwich and conform to the shape of the plug. In this embodiment, the metal sheet in contact with the plug is perforated to allow gas to escape. Alternatively, the space area between the non-perforated sheets 2 and 3 can be evacuated.

The plug tool remains in place and air pressure is maintained while the sand inch is cooled to a temperature that does not cause delamination.

The method shown in FIGS. 4 and 5 can be carried out by a "bubbling" step shown in FIG. 6, in which air pressure is first applied to the surface of the sheet 3; The sheet 2 is not in contact with the mold and the edges of the sandwich are clamped. Thereafter, as shown in FIG. 4, the male mold is inserted into the created "bubble" and air pressure is applied to the sheet 2, as shown in FIG.

In this method, the sandwich is completely deformed by air pressure and there is no need to apply any deforming forces to the tool 7. Since air pressure is applied to both sides of the sand inch, neither sheets 2 nor 3 should be perforated.

The above operations can be performed using currently used forming equipment for deforming metal sheets. Instead of applying fluid pressure K,
The sandwich is deformed by applied force using a solid die. A variety of shapes can be formed for the article, including double curvatures, i.e. curvatures of two or more axes in the plane of the first intersecting flat sheet. Some items have

The method described above can be used for attaching shaped articles of composite material to either or both sides of the metal sheet used in the deformation process, or even for attaching nothing at all. The above method can be used to manufacture articles from metal sheets adhered to a composite body at only one point on the surface of the article. An example of such an article is shown in FIG. The article comprises a metal sheet deformed as described above, having a patch IC and strip 11 of composite material adhered to the inner surface at i locations. This article can be created by the method described above using a sand inch in which each part of sheets 2 and 3 is separated by sheet 1.

FIG. 8 shows a method of fabricating a tubular shaped body TW of a fiber-plastic composite. Tubular mold 1 consisting of a pair of half molds
2 is incorporated and used, and the above half mold is assembled into 13 by a known method.
The mold is integrally clamped. Each month of fiber-plastic presoreg sheet is placed inside the mold,
A layer 14 is produced adjacent to its inner surface. The prepregs may be integrated by known techniques such as circular braiding or by the use of partial annular members. A flattable, plastically deformable metal nozzle 15 is then inserted inside the layer 14, the integral member is heated at the temperature required for plastic deformation of the norijon and prepreg layer, and air pressure is applied to the nozzle. ? 'l) Press the layer 14 into the mold wall. Once layer 14 has solidified into a rigid tube shape, the temperature of the integral member is lowered, the parison is deflated, and the mold is opened to remove the tube. The mold 12 can have a circular, oval or other cross-sectional shape according to the desired cross-sectional shape of the composite tube.

FIG. 9 illustrates a method for assembling upstanding members, in this case brackets, on the surface of the composite body.

The bracket is made of the same material as the composite body.

The mold is separated by gaps 19 into three parts 16, 17 and 1
8, and a rising arm of a bracket 20 made of a fiber-plastic composite sheet is inserted into this gap. A layer of fiber-plastic composite is placed on the mold surface and surrounds each portion of the bracket extending above the mold surface, and a sheet of "Spraul" alloy 2
2 is placed in contact with the composite. When heat and pressure are applied to the alloy sheet, the layer 21 of composite material is deformed and solidified, while mold sections 16 and 18 are pressed against section 17, compressing the arms 20 of the bracket. Upon releasing the pressure from the sheet 21, the molds are separated from each other and the arms 20 are removed from the mold.

The method shown in FIGS. 10 and 11 is the same as that in FIG. However, with this method,
The seat 3 is provided with external and internal raised portions 31, 32, and the seat 2 is provided with holes or quadrants 33.34 opposite the raised portions. The raised portions are dimensioned to fit within the holes or recesses when the sheets 2 and 3 are mated. As shown in FIG. 10, a layer of fiber-plastic composite is disposed between the sheets and, upon application of pressure, the outer raised portion 31 is located a short distance externally from the composite layer and the inner raised portion 32. forms holes in the composite sheet. As shown in FIG. 11, when a deforming pressure is applied to sheet 2, sheets 2 and 3 move together and the raised portion of sheet 3 is inserted into the hole in sheet 2. During this operation, the compressed layer 1 is pressed against the sides of the raised section, so that the sides of this raised section form the entire edge of the shaped sheet of composite.

to be accomplished. The outer part 31 forms the outer edge of the sheet 1 and the inner part 32 forms a hole in the sheet 1.

By providing suitably arranged raised portions using this method, a sheet with any number of holes having a desired shape is produced, the sheet having a desired outer circumferential shape, and having this shape. is determined by the outer portion 31. The outer raised portion forms a continuous barrier around the edge of the sheet 1 and delimits the entire circumference of the sheet.

In the case of a method similar to FIGS. 10 and 11, sheet 3
has equivalent rises, but sheet 2 has a continuous surface without holes. In this case, the rising portion is sheet 2
0 surface, but is not inserted, and the 10th
The shape of the molded sheet is determined in the same manner as in the modified example shown in FIGS. This modification is applicable to a sandwich consisting of only one sheet, in which case the raised portion on sheet 3 contacts the surface of the mold instead of sheet 2.

FIG. 12 illustrates a method of forming a composite article in which the composite material is subjected to a vacuum during deformation to remove trapped gases. In this method, the sandwich consisting of composite layer 1 and sheets 2 and 3 is integrated as in FIG. 1 and surrounded by a rigid airtight frame 41. The frame 41 engages around the entire periphery of the sheets 2 and 3 to form an airtight area. Frame 41 has at least one hole 42 in communication with the end of conduit 43. conduit 4
The other end of 3 is connected to a known vacuum pump (not shown). After assembly as shown in FIG. 12, the hermetic region is evacuated through conduit 43, the assembly is heated to the deformation temperature and deformed by the pressure applied to the sheet 2. , during which time a vacuum is maintained in the hermetic region to remove the gas present between the sheets 2 and 3. The assembly is then cooled, the vacuum released and the frame 41
Remove.

[Brief explanation of drawings]

FIG. 1 shows the overall construction of a sandwich comprising a sheet of fiber-thermoplastic composite between two metal sheets. FIG. 2 schematically shows how the sandwich 4 of FIG. 1 can be modified. FIG. 3 is a diagram schematically showing a deformation method similar to FIG. 2. 4 and 5 schematically illustrate another method of deforming the sheet of FIG. 1. FIG. 6 shows a modification of the method of FIGS. 4 and 5. FIG. 7 shows an article obtained using the above method. FIG. 8 is a diagram schematically showing a method of cutting a tubular composite article. FIG. 9 is a diagram schematically illustrating a method of manufacturing a composite article having an upright member. FIGS. 10 and 11 are diagrams schematically illustrating another method of deforming a composite material. FIG. 12 is a diagram schematically showing still another method of molding a composite material. 1... Composite material sheet, 2.3... Metal sheet, 4
...Female mold, 7. Plug tool, 12. Tubular mold, 14. Layer, 15. Metal parison. Engraving of the following margin drawings (no changes in content) FIG, 3 FIG, 6 FIG, 10 FIG, 11 FIG, 12 Procedural amendment (method) July 16, 1985

Claims (1)

[Claims] 1. A method for molding a shaped article of a plastic composite comprising fibers dispersed in a matrix of thermoformable material,
contacting at least one surface of the body of the composite with a metal sheet that is plastically deformable at high temperatures, at a temperature at which the sheet is plastically deformable and at a temperature at which the body conforms to the shape of the sheet; A method for molding a shaped article of a plastic composite, the method comprising the steps of: pressing a sheet against the surface of the body while plastically deforming the sheet to shape the body. 2. The method of claim 1, wherein the thermoformable material is thermoplastic. 3. The method of claim 1, wherein the thermoformable material is thermosetting. 4. The method according to claim 1, 2 or 3, wherein the main body of the composite comprises a sheet having a thickness of 0.25 to 25 mm. 5. The main body of the composite consists of a preformed reinforced plastic sheet containing laminated fibers, and when the metal sheet is pressed onto the main body, the composite sheet is rotated about at least one axis in the plane of the composite sheet itself. 5. A method according to any one of claims 1 to 4, which is curved. 6. The body of the composite consists of an assembly of prepreg sheets, and the prepreg sheets are reinforced together when pressing the metal sheet onto the body. The method described in section. 7. The method according to any one of claims 1 to 6, wherein the metal sheet is superplastic. 8. Claims 1 to 7, in which a body is arranged between the metal sheet and another sheet of deformable material, and both sheets and the body are deformed when pressing the metal sheet against itself. The method described in any one of the above. 9. The method according to claim 8, wherein the other sheet is perforated to allow gas trapped between the sheets to escape. 10. The method according to claim 8, wherein the space between the metal sheet and the other sheet is evacuated to remove gas between the sheets. 11. The periphery of the sheet is matched by a rigid airtight frame to form an enclosure surrounding the main body, the frame has a hole, and a means for creating a vacuum inside the enclosure is connected to this hole, so that the inside of the enclosure is 11. The method of claim 10, wherein the metal sheet is pressed against the body while applying a vacuum to the enclosure and maintaining the vacuum within the enclosure. 12. The method of claim 11, wherein after deformation of the sheet and body, a vacuum is maintained within the enclosure while allowing the body to cool. 13. The method according to any one of claims 1 to 12, wherein the metal sheet comprises an inflatable diaphragm or a parison. 14. Any one of claims 1 to 13, wherein at least one member to be attached to the main body is arranged in contact with the main body, and is attached to the main body to shape the main body when the sheet is plastically deformed. The method described in paragraph (1). 15. When placing the main body between the metal sheet and the mold surface and pressing the metal sheet against the main body and pressing the main body against the mold surface,
Claims 1 to 7 that transform the metal sheet
The method described in any one of the preceding paragraphs. 16. A hole is provided in the mold surface, a member to be attached to the main body is arranged in the hole, and the member is attached to the main body when the main body is pressed against the mold surface.Claim 15 Method described. 17. The metal sheet has at least one raised portion extending into or around the body when the sheet is pressed against the body, the raised portion extending in a direction transverse to the sheet. 17. A method according to any one of claims 1 to 16, for defining edges of a shaped article. 18. A body is disposed between the metal sheet and another deformable sheet having holes opposite the raised portion;
18. The method of claim 17, wherein the raised portion is inserted into the hole when pressing the metal sheet onto the body. 19. According to any one of claims 1 to 18, wherein the main body is composed of a plurality of separate pieces of the composite, and the pieces are integrated into one body when pressing the sheet against the main body. Method described. 20. The method according to any one of claims 1 to 19, wherein a lubricant is applied between the surface of the metal sheet and the main body. 21. interposing a layer of material between the metal sheet and the body;
20. A method according to any one of claims 1 to 19, wherein the layer of material is adhered to the shaped article when pressing the sheet against the body. 22. According to any one of claims 1 to 19, wherein an adhesive is applied between the surface of the metal sheet and the main body, and the sheet adheres to the main body when pressed against the main body. Method described.