DE102013223519A1 - Fiber-plastic composite component and method for producing a fiber-plastic composite component, in particular a body component for a motor vehicle - Google Patents

Abstract

In particular, a method for producing a fiber-plastic composite component according to the present invention comprises the following steps: producing a preform made of an endless fiber impregnated with a plastic matrix material, applying a molding compound of the plastic matrix material or another plastic matrix material and unoriented fibers to the preform, and compressing the preform Preform and the molding compound in a pressing tool.

Description

The present invention relates to a method for producing a fiber-plastic composite component, and in particular to a method for producing a body component for a motor vehicle. Furthermore, the present invention relates to a fiber-reinforced plastic composite component and in particular a body component for a motor vehicle, which is produced by such a method.

Fiber-reinforced plastic composite components are used in larger numbers, for example in the automotive industry or in the aerospace industry. For the industrial production of fiber-reinforced plastic composite components, which are subject to greater rigidity and strength requirements of the component, semi-finished fiber or semi-finished fiber-matrix products, also called prepregs, are used. There are several methods for making fiber composite components from these semi-finished products. In an autoclave process, a fiber-matrix semifinished product is "baked" under pressure and temperature. In a wet pressing process, fiber-matrix semi-finished products are pressed into the component mold. In a resin injection process, a "dry" semi-finished fiber product is impregnated under high pressure with the plastic matrix and brought into the corresponding component shape. Such a method is known as RTM (Resin Transfer Molding).

Moreover, it is known to use fiber-matrix semi-finished products in the form of a mixture of a thermosetting plastic matrix or a thermoplastic matrix and so-called long fibers, which usually have a length of 1 to 50 mm, for producing a fiber-plastic composite component. Such fiber-matrix semi-finished products are further processed in different pressing processes. Such pressing methods are known as SMC (sheet molding compound) and BMC (bulk molding compound). The term PMC (press molding compound) is used here as an umbrella term.

In the case of the SMC and BMC processes, it is generally possible to produce parts with a complex geometry that are generally less bulky than those processes in which a prepreg is processed with continuous fiber.

It is the object of the present invention to provide a method for producing a fiber-plastic composite component, in particular a body component for a motor vehicle, as well as a fiber-plastic composite component produced by the method, which has sufficient rigidity and strength in a complex geometry.

This object is achieved by a method for producing a fiber-reinforced plastic composite component, which has the features of patent claim 1. Furthermore, this object is achieved by a fiber-plastic composite component having the features of claim 9. Advantageous developments of the invention are mentioned in the dependent claims.

• – Herstellen eines mit einem Kunststoffmatrixmaterial imprägnierten Vorformlings aus einer Endlosfaser,
• – Auftragen einer Pressmasse aus dem Kunststoffmatrixmaterial oder einem anderen Kunststoffmatrixmaterial und ungerichteten Fasern auf den Vorformling, und
• – Verpressen des Vorformlings und der Pressmasse in einem Presswerkzeug.

In particular, a method for producing a fiber-plastic composite component according to the present invention comprises the following steps:

• Producing a preform made of an endless fiber impregnated with a plastic matrix material,
• Applying a molding compound of the plastic matrix material or another plastic matrix material and undirected fibers to the preform, and
• - Pressing the preform and the molding compound in a pressing tool.

The fiber-reinforced plastic composite component is preferably a body component for a motor vehicle.

After the production of the fiber-plastic composite component, the preform essentially forms a basic element of the fiber-plastic composite component, and after the production of the fiber-plastic composite component, the pressed mass essentially forms an integrally molded part of the fiber-plastic composite component.

The term "impregnated" means that the fibers of the preform are impregnated with the plastic matrix material. The term plastic matrix material in this context includes not only the plastic material as it is present in the fibrous composite component produced, but also a plastic precursor that reacts in the course of the manufacturing process to the plastic material as it is present in the fiber composite component produced.

Preferably, the molding compound consists of the same plastic matrix material, with which the preform is also impregnated, so that an integral connection of the material of the preform and the material of the molding compound is particularly simple and durable. However, it is also possible for the molding compound to use a different plastic matrix material than the material with which the preform is impregnated. Non-oriented fibers means that they are present in an undefined random orientation in the molding compound. Unoriented fibers may also be referred to as random fibers.

The method described makes it possible to provide a fiber-reinforced plastic composite component which has a more complex geometry than a wet-pressing method of a preform an endless fiber or with a related to the prior art RTM (Resin Transfer Molding) method would be possible.

The fiber-reinforced plastic composite component is preferably a component with an essentially flat, in particular three-dimensional, extension. The component may in particular have a plurality of surfaces which are arranged at an angle to one another.

According to a preferred development, the step of pressing the preform and the molding compound takes place in such a way that the molding compound penetrates into the preform and further penetrates into at least one additional recess or into a plurality of additional recesses in the molding tool.

The recess may be formed such that the depression, in cooperation with the molding compound and the pressing step, forms a molding element, for example a reinforcing element, in particular a rib, and / or a connecting element for the positive connection of a liner element to the fiber-plastic composite component.

This makes it possible with a simple method with a few steps to form very effective Anformelement as reinforcements / stiffening and / or fasteners on the fiber-plastic composite component integrally with the fiber-plastic composite component.

According to a further preferred development, the insert element is inserted into the pressing tool prior to the step of pressing the preform and the molding compound, wherein this step is optionally performed before the step applying a molding compound, so that in the step of pressing the preform and the molding compound, the insert element positively can be surrounded by the molding compound.

The insert element can be formed, for example, from a plastic, a fiber-reinforced plastic composite material or a metallic material. In particular, the insert element may have a connection device for attaching attachments. This connecting device may for example have a thread, so that attachments can be screwed to the fiber-plastic composite component. However, the insert element may additionally or alternatively have a stiffening or strength-increasing function for the fiber-reinforced plastic composite component.

According to a preferred development of the method according to the invention, the preform is produced from an endless fiber already impregnated with the plastic matrix material. Alternatively, first a dry semi-finished product, d. H. a fiber only semi-finished product which does not have a plastic matrix material from which the continuous fiber is made. Such a semi-finished product may be a woven fabric, a knitted fabric, a knitted fabric or a scrim. In a subsequent step, the dry semifinished product is then impregnated with the plastic matrix material and thus forms the preform, which is then pressed together with the molding compound in the pressing tool.

Preferably, the preform is produced in a winding process.

In the winding process, only one type of fiber, i. H. a fiber material, are used. Alternatively, for example, two or more different types of fibers may be used. Also in another processing of continuous filaments, only one type of fiber or multiple types of fibers can be used.

As a result, the different advantageous properties of different types of fibers can be used.

The plastic matrix material may be a thermoset material. In the case of thermoset materials, in particular the above-mentioned plastic precursors can be used. Examples of such a thermosetting material are epoxy resin, phenolic resin, vinyl ester resin and / or polyurethane resin. Alternatively, the plastic matrix material may also be a thermoplastic material. Examples of such a thermoplastic material are polypropylene, polyethylene, polyphenylene ether, polyphenylene sulfide and polyphthalamide.

According to a development of the present invention, the continuous fibers of the preform may be carbon fibers, glass fibers, aramid fibers, polypropylene fibers, polyethylene fibers and / or natural fibers. When multiple types of fibers are combined, a combination of carbon fiber and polypropylene fiber or a combination of carbon fiber and polyethylene fiber is advantageous. For the undirected fibers of the molding compound, basically the same fibers as in the preform can be used. But it is also possible to use other fibers. Preferred fibers for the molding compound are carbon fibers, glass fibers, aramid fibers and / or natural fibers. The fibers of the molding compound are advantageously long fibers having a length of 1 mm to 50 mm. A preferred fiber length for the molding compound is 20 mm to 50 mm. But it can also be used short fibers with a length up to 1 mm.

The present invention further relates to a fiber-plastic composite component produced by a method as described above. The fiber-reinforced plastic composite component may in particular be a body component for a motor vehicle. The fiber-reinforced plastic composite component is preferably an integral, preferably one-piece, body flap carrier component.

The present invention furthermore relates to a fiber-plastic composite component which has a base element which is formed substantially from an endless fiber plastic composite material on which at least one molding element is formed, wherein the molding element is formed from a short and / or long fiber plastic composite.

The base member may also be referred to as the main body since it forms the majority of the fiber-plastic composite component. The basic element forms the basic structure of the fiber-reinforced plastic composite component.

The molding element can preferably be a reinforcing element and / or a connecting element for the positive connection of a liner element to the base element.

The insert element is preferably an amplifying device and / or a connecting device for connecting a further component or for connecting the fiber-plastic composite component to a further component.

The fiber-reinforced plastic composite component can in particular be a body component, for example a body flap carrier component, in particular an integral, one-piece carrier and / or frame component of a motor vehicle door for a motor vehicle. In particular, the body flap support member may have a function determining the rigidity and strength of the body flap.

In the case that the fiber-plastic composite component is a body flap support component, the base element may form a door frame and / or a door inner panel and / or a window sill and / or a mirror triangle and / or a window frame. Furthermore, the shaping element can form a rib for reinforcing the base element. Alternatively or additionally, the molding element can be a connecting element for the positive connection of a Einlegerelements as a hinge reinforcement and / or Einlegerelements as a lock reinforcement and / or a Einlegerelements for connecting a side impact beam and / or a Einlegerelements for connecting a Türaussenhautverstärkung and / or Einlegerelements in the form of a Be window frame.

As a result, a number of parts for a body clamp carrier component can be significantly reduced.

As the plastic matrix for the base member, the materials described above with respect to the continuous fiber plastic matrix may be used. Likewise, the above-mentioned materials for continuous fibers can be used. In addition, the plastic matrix used for the molding element (s) may be the plastic matrix described above with respect to the long fiber plastic matrix. Likewise, the above-mentioned long fiber materials can be used.

The described features of the developments of the method according to the invention and the fiber-reinforced plastic composite component according to the invention can as far as possible be combined with each other as desired.

Below is a brief description of the figures.

1 FIG. 12 is a schematic perspective view of an open crimping tool before crimping a preform and a molding compound according to a first embodiment of the present invention. FIG.

2 FIG. 13 is a schematic perspective view of a part of the open die according to the first embodiment of the present invention. FIG.

3 is a schematic perspective view of the part of the closed pressing tool of 2 according to the first embodiment of the present invention.

4 is a schematic, sectional side view of an open pressing tool according to a second embodiment of the present invention.

5 is a schematic, sectional side view of the closed pressing tool of 4 according to the second embodiment of the present invention.

6 is a schematic, sectional side view of a fiber-plastic composite component, which, as in 4 to 5 is produced, according to the second embodiment of the present invention.

7 FIG. 12 is a schematic side perspective view of a vehicle side door support member according to a third embodiment of the present invention. FIG.

8th is a schematic, sectional detail view of the Kraftfahrzeugseitentürträgerbauteils along the plane AAA in 7 according to the third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be explained with reference to the figures.

First of all, referring to the 1 to 3 a method for producing a fiber-plastic composite component according to a first embodiment described.

1 shows a schematic perspective view of an open pressing tool with a lower part 7 and a top 9 , On the lower part 7 is a preform 3 placed. The preform 3 is preferably produced in a winding process from an impregnated continuous carbon fiber. On the preform 3 are in several places additional molding compound elements 5 applied or angordnet. The molding compound elements 5 , which are intended for molding elements according to the present invention, consist of a mixture of plastic matrix material and long fibers. The long fibers are preferably made of carbon. Furthermore, in 1 to see that the preform 3 a section 11 or an opening 11 having. That in the 1 shown left molding compound element 5 and that in the 1 shown right molding compound element 5 should each form reinforcing elements as stiffening ribs. The middle molding compound element 5 is annular and is intended as a connecting element for the positive connection of a in the 1 serve not shown insert element. The insert element is in this case before the closing of the press tool at the space provided within the annular molding compound element 5 positioned. The Einlegerlement may for example be formed of metal, which serves as a connection element and / or reinforcing element. As a connection element, it may have fastening holes and / or fastening projections. As a reinforcing element, it locally increases a strength and / or rigidity of the fiber-reinforced plastic composite component produced by the method according to the invention.

When closing the pressing tool penetrates the molding compound 5 in dedicated wells 91 , in the 2 and 3 are shown in the upper part 9 of the pressing tool.

In 2 is a partial section of the open pressing tool with the lower part 7 and the top 9 shown. The top 9 has the wells 91 on.

Opposite the wells 91 is on the preform 3 a predetermined amount of molding compound 5 applied.

When closing the pressing tool while the molding compound 5 on the one hand in the preform 3 on the other hand, the material differs into the recesses 91 out. According to this basic principle, a wide variety of moldings, such as the reinforcing elements mentioned, for example reinforcing ribs, can be formed on a fiber-plastic composite component. In 3 is the closed pressing tool of 2 shown, with the molding compound 5 the cavity of the wells 91 fills.

When opening the pressing tool, the resulting plastic fiber composite component with long fibers reinforced, the wells 91 corresponding reinforcing ribs.

For connection of the insert element not shown not shown wells are provided. These recesses are provided such that the molding compound 5 when closing the pressing tool is positively pressed around edges of the insert element.

The preform 3 According to the first embodiment forms after the manufacturing process of the fiber-plastic composite component, a base element made of continuous fiber plastic composite material according to the present invention. The molding compound elements 5 Forming elements according to the invention form a long fiber plastic composite material - on the one hand reinforcing elements in the form of ribs and on the other elements for positive connection of the insert element.

Preferably, according to the first embodiment, long fibers in a range of 20 to 50 mm are used. The length of the continuous fibers exceeds a multiple of the length of the long fibers and have a usual length for a winding process. The continuous fibers are preferably carbon fibers. The long fibers are also preferably carbon fibers, which may originate, for example, from a recycling process of fiber-reinforced plastic composite components. But there are also any other types of fibers conceivable, which are mentioned above in the general description of the invention. As plastic matrix materials, all the materials mentioned above in the general description of the invention are also conceivable.

With reference to the 4 to 6 the principle of the method according to the present invention to a second embodiment is explained in addition, in particular to differences from the first embodiment is a description of commonalities with the first embodiment partially omitted.

In 4 is a sectional side view of an open pressing tool with a lower part 7 and a top 9 shown. In the second embodiment are sections with molding compound 5 , in other words pressed mass elements 5 from a mixture of long fibers and a plastic matrix material, on an underside of a preform 3 applied. The preform 3 As with the first embodiment, it consists of an endless fiber impregnated with a plastic matrix. When closing the pressing tool, as in 5 is shown, the molding compound 5 in intended for them wells 71 in the lower part 7 pressed the pressing tool. At the same time becomes an edge of the preform 3 reversed or reshaped.

At the in 4 and 5 The process shown results in a fiber-reinforced plastic composite component 1 , this in 6 shown with folded down edges (the directional reference refers only to the illustration in the figure) folded edges, in other words with a downwardly facing flange, the edges with long fiber reinforced ribs 103 supported or reinforced. The original preform 3 forms in the finished fiber composite component 1 according to the second embodiment, a basic element 101 from an endless fiber plastic composite material, which has a flat, three-dimensional basic structure of the fiber-reinforced plastic composite component 1 pretends while the ribs 103 Forming elements according to the invention, in particular reinforcing elements, form from a long-fiber plastic composite material. The basic element 101 and the ribs 103 are integrally connected to each other and form the one-piece fiber-reinforced plastic composite component 1 ,

The following is a third embodiment of the present invention with reference to FIG 7 and 8th described. While referring to the 1 to 6 Essentially, a method for producing a schematically greatly simplified or an abstract fiber-plastic composite component according to the first and the second exemplary embodiment is described below, with reference to FIG 7 and 8th a fiber-plastic composite component in the form of a motor vehicle door frame component 1 according to the third embodiment, wherein for similar or comparable elements the same reference numerals are used as in the previously described embodiments.

In 7 is a perspective side view of the motor vehicle door frame component 1 according to the second embodiment of the present invention. The vehicle door frame component 1 can with reference to 1 to 6 described, inventive method be prepared.

This in 7 shown motor vehicle door frame component 1 has a main body or main body 101 from an endless fiber reinforced plastic, ie an endless fiber composite material. The main body 101 has a section in the middle 11 on. Further, on the body 101 ribs at certain designated points 103 for reinforcement and stiffening of the essentially three-dimensional, flat basic body 101 of the vehicle door frame component 1 intended. Ribs 103 , the forming elements, in particular reinforcing elements, according to the present invention, consist of a reinforced with long fibers plastic, ie a long fiber plastic composite material. In particular, the ribs run 103 in a direction transverse to adjacent, obliquely extending surfaces (analogous to the ribs 103 of the second embodiment), so that the surfaces are stiffened to each other. Furthermore, the vehicle door frame component has 1 a depositor element 13 to which door hinges can be attached and which may also be referred to as hinge reinforcement. The insert element 13 is made of a metallic material, such as steel. The insert element 13 is about formations 105 , the Anformelemente, in particular fasteners, according to the present invention, form-fitting manner to the body 101 attached or with the main body 101 connected. The formations 105 exist as well as the ribs 103 made of a plastic reinforced with long fibers. In addition, the motor vehicle door frame component has 1 a mirror triangle 15 on which a side mirror can be attached, as well as a window railing 17 on. The mirror triangle 15 can be reinforced with a Anformungelement invention of a reinforced with long fibers plastic.

In 8th is a sectional detail view of 7 shown. In particular, the shows 8th a section along an indicated by dashed lines xy -plane AAA in 7 , An xy plane is a plane parallel to a vehicle longitudinal direction and a vehicle transverse direction in an installed state of the vehicle door frame member 1 in a motor vehicle.

8th shows a portion of the vehicle door frame component 1 in which the deposit element 13 is arranged. In particular, it is shown that the insert element 13 on the body 101 abuts and by the formations 105 positively with the body 101 connected is. The formations 105 engage around an end edge of the insert element 13 , In particular, the moldings 105 the entire end edge 14 of the insert element 13 encircling or the end edge 14 only partially encompass. There may also be holes in the insert element over which the insert 13 alternatively or additionally by means of the formations 105 , which penetrate the holes, form-fitting to the body 101 are attached.

In the third embodiment, the materials may be used, which are already mentioned in relation to the first embodiment.

The vehicle door frame component 1 according to the third embodiment has no window frame. Alternatively, a window frame may be part of the body 101 be. In a further alternative, a window frame made of a suitable material as insert element can form-fit with the base body 101 be connected. Such a complex component according to the third embodiment, is usually in the conventional sheet metal construction only from many different items that are joined together in many stages for joining, with a required in a motor vehicle body strength and rigidity represented. This in 7 shown motor vehicle door frame component 1 In contrast, it can be produced in a single joining step. Furthermore, the fiber-reinforced plastic composite construction according to the invention allows a low weight of the component with the required strength and rigidity.

If such a motor vehicle door frame component were to be produced only in a conventional wet pressing method or an RTM method, additional reinforcing element and attachments to be subsequently attached would be necessary, for which further joining steps are required.

If the motor vehicle door frame component were to be produced only with a BMC or SMC method, overall the stiffness and strength could not be achieved as in the case of the component according to the invention due to the shorter fibers.

Claims (16)

Method for producing a fiber-reinforced plastic composite component ( 1 ), in particular a body component for a motor vehicle, comprising the steps of: - producing a preform impregnated with a plastic matrix material ( 3 ) of an endless fiber, - application of a molding compound ( 5 ) of the plastic matrix material or other plastic matrix material and non-directional fibers on the preform ( 3 ), and - pressing the preform ( 3 ) and the molding compound ( 5 ) in a pressing tool ( 7 . 9 ). Method according to claim 1, wherein the step of pressing takes place in such a way that the molding compound ( 5 ) in the preform ( 3 ) and into a depression ( 71 . 91 ) in the pressing tool ( 7 . 9 ) penetrates. Method according to claim 2, wherein the recess ( 71 . 91 ) in cooperation with the molding compound ( 5 ) and the pressing step, a molding element ( 103 . 105 ), for example a reinforcing element, in particular a rib ( 103 ), and / or a connecting element ( 105 ) for the positive connection of a Einlegerelements ( 13 ) to the fiber-plastic composite component ( 1 ) trains. Method according to claim 3, wherein before the step of pressing the insert element ( 13 ) in the pressing tool ( 7 . 9 ) is inserted, which in the crimping step form-fitting manner of the molding compound ( 5 ) is surrounded. Method according to one of the claims 1 to 4, wherein the preform ( 3 ) is produced from a continuous fiber already impregnated with the plastic matrix material and / or a dry semi-finished product, in particular a woven fabric, a knitted fabric, a knitted fabric or a scrim, consisting of the continuous fiber is produced and this is impregnated in a subsequent step with the plastic matrix material. Method according to one of claims 1 to 5, wherein the preform ( 3 ) is produced in a winding process, wherein only one type of fiber or at least two different types of fibers are used. Method according to one of claims 1 to 6, wherein the plastic matrix material of the preform ( 3 ) and / or the molding compound ( 5 ) is a thermosetting material, in particular based on epoxy resin, phenolic resin, vinyl ester resin and / or polyurethane resin, or a thermoplastic material, in particular based on polypropylene, polyethylene, polyphenylene ether, polyphenylene sulfide and / or polyphthalamide. Method according to one of claims 1 to 6, wherein the continuous fibers of the preform ( 3 ) Carbon fibers, glass fibers, aramid fibers, polypropylene fibers, polyethylene fibers and / or natural fibers, and / or wherein the non-directional fibers of the molding compound ( 5 ) Carbon fibers, glass fibers, aramid fibers and / or natural fibers whose Length especially in a long fiber area, preferably 20 mm to 50 mm fiber length, is. A fiber-reinforced plastic composite component which is produced by a method according to one of the claims 1 to 8, wherein the fiber-plastic composite component is a body component for a motor vehicle, in particular an integral, in particular one-piece, body flap carrier component ( 1 ), which is formed by an integral composite of the preform element ( 101 ) of a continuous fiber plastic composite and formed from the molding compound Anformelement ( 103 . 105 ) is formed from short and / or long fiber plastic composite. Fiber-reinforced plastic composite component according to claim 9, wherein the molding element comprises a reinforcing element for reinforcing the base element and / or a connecting element ( 105 ) for the positive connection of a Einlegerelements ( 13 ) to the basic element ( 101 ). A fiber-reinforced plastic composite component according to claim 11, wherein the body flap support component is an integral, one-piece support and / or frame component of a motor vehicle door, wherein the basic element ( 101 ) forms a door frame and / or a door inner panel and / or a window sill and / or a mirror triangle and / or a window frame, and / or wherein the molding element is a rib ( 103 ) to reinforce the primitive ( 101 ), and / or wherein the molding element is a connecting element ( 105 ) for the positive connection of a Einlegerelements ( 13 ) as a hinge reinforcement and / or a Einlegerelements as a lock reinforcement and / or a Einlegerelements for connecting a side impact beam and / or a Einlegerelements for connecting a door skin reinforcement and / or a Einlegerelements in the form of a window frame. Fiber-reinforced plastic composite component, in particular a body component for a motor vehicle, having a basic element ( 101 ) formed of a continuous fiber plastic composite, wherein at the base element ( 101 ) at least one molding element ( 103 . 105 ) is integrally formed, wherein the molding element ( 103 . 105 ) is formed from a short and / or long fiber plastic composite material. Fiber-reinforced plastic composite component according to claim 12, wherein the molding element is a reinforcing element ( 103 ) and / or a connecting element ( 105 ) for the positive connection of a Einlegerelements ( 13 ) to the basic element ( 101 ). Fiber-reinforced plastic component according to claim 13, wherein the insert element ( 13 ) is an amplifying device and / or a connection device for connecting a further component. Fiber-plastic composite component according to one of the claims 12 to 14, wherein the body component is an integral, in particular one-piece, body flap support component ( 1 ) is. A fiber-reinforced plastic composite component according to claim 15, wherein the body flap support component is an integral, one-piece support and / or frame component of a motor vehicle door, wherein the basic element ( 101 ) forms a door frame and / or a door inner panel and / or a window sill and / or a mirror triangle and / or a window frame, and / or wherein the molding element is a rib ( 103 ) to reinforce the primitive ( 101 ), and / or wherein the molding element is a connecting element ( 105 ) for the positive connection of a Einlegerelements ( 13 ) as a hinge reinforcement and / or a Einlegerelements as a lock reinforcement and / or a Einlegerelements for connecting a side impact beam and / or a Einlegerelements for connecting a door skin reinforcement and / or a Einlegerelements in the form of a window frame.

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