DE10340561A1 - Aircraft used as rotary-wing aircraft, e.g. helicopter, comprises structural component at risk from impact/explosion which is made of lightweight composite material with rigid, strong support layer and fiber-reinforced elastomer layer - Google Patents

Abstract

Aircraft, especially a rotary-wing aircraft, especially a helicopter, comprises a structural component at risk from impact or explosion which is made of a plate- or shell-like lightweight composite material with at least one first rigid, strong support layer (2) produced from at least one metal material or a composite material, and at least one elastomer layer (4) fixed to the support layer. The elastomer layer is completely penetrated by reinforcing fibers (6) and forms a matrix for the reinforcing fibers. Preferred Features: The support layer comprises an aluminum material. The structural component is a base assembly or a base assembly component of the aircraft, a component of the power plant, a fuel tank arranged in a base element, or a fire-protection element.

Description

TECHNICAL TERRITORY

The invention relates to a plate or cupped Lightweight composite material, an intermediate product for such a lightweight composite material and methods for manufacturing and processing the lightweight composite material. Furthermore, the invention relates to particularly suitable uses for such Lightweight composite material.

STATE OF THE ART

From the DE-OS 38 34 205 A composite material is known, comprising two rigid, tensile carrier layers, which are made of a metal material, namely steel, and an elastomer layer arranged between these carrier layers and firmly connected to the carrier layers. On the inner sides of the carrier layers facing the elastomer layer, these are each provided with a thin layer of a flexible metal mesh material which projects slightly, ie only close to the surface, into the elastomer layer. This metal mesh material forms a type of anchoring which is intended to improve the areal cohesion between the elastomer layer and the respective carrier layer.

A similar composite, however without the aforementioned Metal mesh layer is disclosed in U.S. Patent No. 6,050,208.

Furthermore, so-called Fiber-plastic composite materials known which reinforcing fibers, such as glass, aramid or carbon fibers, boron fibers, ultra-strong Have polyethylene fibers etc., which are in a plastic matrix, such as a polyester or epoxy resin are embedded. Such materials are used in vehicle construction, especially aircraft construction quite common.

Furthermore, fiber-plastic-metal composite materials are known, as are marketed, for aeronautical applications, for example, under the trade name Glare ^® or Arall ^® from. Fokker Aerostructures BV. These materials are plate-shaped composite elements made of sheet metal and fiber-plastic composite panels that are glued together. For example, Glare ^® is a composite of at least two aluminum sheets and a fiber-epoxy composite panel.

Fiber-reinforced plastic materials and fiber-plastic-metal composite materials have opted for Aircraft applications basically proven and have been found recently also increasingly used in the automotive industry. The processing However, such materials are very demanding, and not only because of the necessary equipment and the necessary craft skills, but also due to the sometimes very different or opposing Properties of the individual materials involved in the respective material composite. For the latter reason, the practical application of Composite materials in a component with a view to a desired one practical use of this component is a complex subject. On Composite material, which for a specific application or processing method is favorable, can stand up for another application or processing method other than highly problematic out.

This is in automotive and aircraft engineering, in which composite materials mostly as highly multifunctional Materials are used, of particular importance, because the Composite materials can due to the problem described above, the sum of the desired for an application Usually do not or do not optimally fulfill properties or do not make optimal use of many material properties.

Recent demands on automotive and aircraft structures relate in particular to passive ones Safety, crash safety, heat resistance, heat insulation, durability against general shock and impact loads such as shelling and flying parts, high dynamic strength and damage tolerance, Tightness, corrosion resistance, Weight saving and ultimately one technically possible easy and economical processability. So it would be desirable, to be able to provide a material which if possible fulfills many of these required properties as optimally as possible.

A special and extremely difficult Crash safety poses a problem in aircraft technology Water what what wing aircraft and rotary wing aircraft equally applies. A crash on water can be different than a crash No landing gear or landing gear on firm land - to reduce impact come into effect. Rather, the crash-related loads directly into the fuselage and or wing structure of the aircraft initiated. Consequently, there are extremely high requirements here the for the structure or the structural components of the aircraft used materials and materials. A similar Problems also arise in the event of a crash on mud or deep snow on. It would be therefore desirable that Improve crash behavior by providing suitable materials to be able to.

PRESENTATION THE INVENTION

The invention is based on the object or the technical problem of creating a novel lightweight composite material which has improved multifunctional properties, in particular with regard to crash safety and thus together has dependent factors. Another aspect of the object on which the invention is based is to provide an intermediate product for producing such a lightweight composite material and a particularly suitable method for processing such an intermediate product or such a lightweight composite material. Yet another aspect of the task is to provide particularly suitable uses for such a lightweight composite material.

The aforementioned task is carried out according to a solved first aspect of the invention by a lightweight composite material according to the invention with the features of claim 1.

This plate or shell-shaped lightweight composite material comprises at least a first rigid, tensile carrier layer, which is made of at least one metal material, and at least one with this backing layer firmly bonded elastomer layer, which is essentially entirely of reinforcing fibers is interspersed and a matrix for the reinforcing fibers forms. A plate-shaped For the purposes of the invention, material also comprises a strip-shaped material.

The basis of the invention The task is also solved by a lightweight composite material according to the invention with the features of claim 2.

This lightweight composite material comprises at least a first rigid, tensile carrier layer, those made of a composite material, in particular a fiber composite material is produced, and at least one with this carrier layer firmly bonded elastomer layer, which is essentially entirely of reinforcing fibers is interspersed and a matrix for the reinforcing fibers forms.

The (soft) penetrated by the reinforcing fibers The elastomer layer is also briefly referred to below as a fiber-elastomer composite layer be designated.

Stiff and tensile means in With regard to the backing layer, that this is significant compared to the fiber-elastomer composite layer greater stiffness and Has tensile strength, which follows from the exemplary description of the for the backing and the fiber-elastomer composite layer used materials and the arrangement of which will become even clearer. The reinforcing fibers can are in an isotropic, anisotropic or orthotropic arrangement, i.e. for example in the form of unidirectional or multidirectional fiber arrangements, Rovings, fiber mats or nonwovens with an agglomerate of individual fibers (Long or short fibers), laid fabrics, woven fabrics, knitted fabrics etc., or in mixed forms be provided from it. Such fiber structures can be both provide single and multi-layered. As reinforcing fibers preferably come fibers made of glass, carbon, aramid, metal, and also natural fibers (e.g. hemp, flax, jute), or a hybrid from these fibers for use.

“Completely made of reinforcing fibers enforced "means in the above context and in the sense of the invention, that the reinforcing fibers are not only on an outer edge area the elastomer layer, but also in other layer or thickness areas the elastomer layer or preferably in the thickness direction equally distributed are. The fiber content in the elastomer layer is approx. 20 to 80%, preferably 30 to 70%, more preferably 35 to 60%, wherein however, the invention is not limited to these ranges of values.

Aluminum, aluminum alloys, steel alloys, including corrosion-resistant steels, titanium and titanium alloys are preferably used for a carrier layer made of at least one metal material. The carrier layer can also be constructed from a plurality of metallic individual layers. A carrier layer made of a composite material can, for example, be a fiber-plastic composite material, both with a matrix of a thermosetting and thermoplastic material, or a fiber-plastic-metal composite material (e.g. ^Glare® ), which is also a can contain a fine mesh made of a copper material, or a mixture of these.

For the elastomer layer, which is the matrix or elastomer matrix for the reinforcing fibers forms, can in principle any suitable elastomer material can be used, in particular also acrylonitrile butadiene rubber (NBR), acrylate rubber (ACM), Butyl rubber, chloroprene rubber (CR), ethylene propylene rubber (EPDM), fluororubber (FKM), rubber or rubber-like materials, such as natural rubber, also hydrogenated nitrile rubber (HNBR), neoprene, nitrile rubber (NBR), polyurethane elastomers (AU, EU), silicone rubber (VMQ), styrene-butadiene rubber (SBR), as well as thermally processable elastomers (TPE).

The lightweight composite material according to the invention has excellent multifunctional properties, such as a low weight, which makes it suitable for lightweight applications or to achieve weight savings, high dynamic resilience, high residual strength after dynamic stresses and generally a high damage tolerance with a low tendency to crack propagation or lower crack propagation speed after damage. In addition, it has good damping properties, especially with high-frequency vibrations, as well as good shock absorption properties. Furthermore, the lightweight composite material according to the invention has good flexural rigidity and very high extensibility with at the same time low tensile and tensile rigidity of the fiber-elastomer composite layer. The material is especially at a metal support layer in its entirety easily deformable or deformable. However, it also has a high dielectric strength or resistance to general impact and impact loads, such as can occur in a crash, by bombardment, an explosion or by flying parts. Due to a low thermal conductivity in the thickness direction, the material according to the invention has a high heat resistance, a high burn-through resistance and thus good fire protection properties. In addition, it is well heat-insulating, liquid-tight and has good corrosion resistance or resistance. Another positive property of the lightweight composite material according to the invention in the embodiment according to claim 1 is its good cold formability, as will be described in more detail below. However, even in the alternative embodiments according to the invention, it is easy to process or produce and allows technically relatively simple and economical production of high-quality components.

With the lightweight composite material according to the invention a new type of material is thus provided which improved multifunctional properties, especially with regard to crash safety and has passive safety, what in aircraft and automotive engineering is of particular interest. The material according to the invention is also capable of a remarkable variety of aircraft and automotive technology properties almost optimally fulfill and opened thus a number of new applications, as will be explained in more detail below becomes.

More preferred and advantageous Design features of the lightweight composite material according to the invention are subject to the dependent Expectations 2 to 7.

According to another aspect the object underlying the invention is achieved by an intermediate product according to the invention with the features of claim 8.

This intermediate to manufacture of a lightweight composite material according to claim 2, comprising: at least a prepreg layer and / or at least one unbound reinforcing fiber layer for the at least one first rigid, tensile composite support layer; and at least one with the prepreg layer or the unbound Reinforcing fiber layer bonded elastomer layer that is essentially entirely of reinforcing fibers is enforced.

Prepreg is generally already used factory-impregnated with special resin or impregnated Scrim and fabric. Under an unbound reinforcing fiber layer is a fiber layer in the sense of the invention, e.g. in the form of a fleece, of a tissue or the like (see above) to understand that not yet is provided with a matrix material (e.g. resin). The unbound reinforcing fiber layer is therefore quite flexible. Both the prepreg layer and the unbound reinforcing fiber layer can in addition to the pure reinforcing fibers in principle other additional components such as a network structure made of thin copper wire or the like. Furthermore, the prepreg layer or the unbound reinforcing fiber layer form-fitting and / or by means of a suitable adhesive, adhesive (including adhesive films), or the like connected to the fiber-elastomer composite layer his. These connections can both flat, entire area as only locally or punctually executed his. moreover can in the intermediate according to the invention the prepreg layer or the unbound reinforcing fiber layer and the Fiber-elastomer composite layer initially a relatively loose composite form, which however represents a unit, and only in a later processing step be firmly connected.

The intermediate product according to the invention is on simple and effective way to process or edit, as will be described in more detail below, and allows it, the lightweight composite material according to the invention rational and economical way to manufacture, including three-dimensional Shapes and components are realizable.

According to another aspect the above-mentioned underlying the invention. Task solved by an inventive method with the features of claim 9.

This method for producing a three-dimensionally shaped lightweight composite material according to claim 2 by means of an intermediate product according to claim 8, which is provided with at least one unbound reinforcing fiber layer for the at least one first rigid, tensile composite support layer comprises the following steps, but not necessarily in the given Sequence: deformation of the unbound reinforcing fiber layer by the application of force; and as a result elastic deformation of the at least one elastomer layer which is substantially completely penetrated by reinforcing fibers, the reinforcing fibers embedded in the elastomer matrix adopting a changed fiber course which essentially follows the elastic deformation due to the elastic deformation; Applying a resinous plastic material to the unbound reinforcing fiber layer (this can be done manually or by machine, for example in an injection or nozzle application process); Curing the applied resin-like plastic material, whereby a stretch-resistant, tensile carrier layer is formed from a hardened, solid fiber-plastic composite; and maintaining the elastic deformation of the elastomer layer and the changed fiber course of its reinforcing fibers by means of the hardened, firm fiber-plastic composite.

In addition, that of the invention underlying above Task solved by a procedure with the features of claim 10.

This method of making a three-dimensionally shaped lightweight composite material according to claim 2 means of an intermediate according to claim 8, which with at least one Prepreg layer for the at least one first rigid, tensile composite support layer is provided, includes the following steps, but not necessarily in the given order: deforming the prepreg layer, preferably under the influence of heat, by force; and thereby elastic deformation of the at least one, essentially complete of reinforcing fibers interspersed elastomer layer; being the one in the elastomer matrix embedded reinforcement fibers through the elasticity of the elastomer matrix essentially one of the elastic deformation following, changed Accept fiber orientation; Harden the at least one prepreg layer under the action of heat; and maintain the elastic deformation of the elastomer layer and the modified Fiber course of the reinforcing fibers by means of the deformed and hardened prepreg layer. Especially when Cold shaping of the prepreg layer must be ensured that the Degree of deformation selected in this way is that the reinforcing fibers do not detach the prepreg layer from its matrix material. in the In case of deformation under the influence of heat in contrast, the matrix material of the prepreg becomes plastic, so here larger deformations carried out can be. Naturally it should also be noted that the reinforcing fibers of the elastomer layer do not detach from the elastomer matrix.

Both in the method according to claim 9 and claim 10 can be deformed by the weight of the intermediate product (e.g. by inserting the intermediate product in a simple lamination form) or by targeted exercise of an outer, flat or linear Force on a predetermined area of the intermediate product (e.g. by vacuum pressing or pressing with Stamp and die). Deformation can be done with the help be carried out by at least one auxiliary tool which has the desired surface shape one from the intermediate or the resulting composite material reproduces the component to be produced. Furthermore, tools can be used to achieve this an improved surface quality of the lightweight composite material become.

The previously described method according to the invention enable it in a simple and effective manner, from the intermediate according to the invention to produce three-dimensionally shaped components. The elastic state of deformation the fiber-elastomer composite layer is completed by the Composite backing layer (i.e. the hardened Prepreg layer or in the hardened plastic material matrix embedded reinforcing fiber layer) "frozen" and stabilized. This can be done through the natural relaxation of the elastic deformed elastomer material are supported. Become the pure Deformation steps are omitted, so are flat, plate or strip-shaped lightweight composite materials according to the invention manufacture.

According to another aspect of Invention is the above Task solved by a procedure with the features of claim 11.

This method for processing a lightweight composite material according to one or more of claims 1 and 3 to 8, with a rigid, tensile support layer, which is made of at least one metal material, a thermoplastic or a thermoplastic fiber composite material, comprises the following steps, but not necessarily in the given order:
Plastic deformation of the at least one carrier layer and thereby elastic deformation of the at least one elastomer layer, which is substantially completely penetrated by reinforcing fibers, the reinforcing fibers embedded in the elastomer matrix adopting a changed fiber course due to the elasticity of the elastomer matrix, essentially following the elastic deformation; and maintaining the elastic deformation of the elastomer layer and the changed fiber course of the reinforcing fibers by means of the plastically deformed carrier layer.

When deforming the carrier layer care must be taken that the degree of deformation is selected such that the resulting deformation of the fiber-elastomer composite layer their reinforcing fibers do not detach from the elastomer matrix.

The plastic deformation of the carrier layer and thus the entire lightweight composite material according to the invention through a suitable forming step, such as printing forms, Train pressure forming, train forming, bending forming, shear forming, in particular also forming with a stamp and die or a molding process, stretch drawing, Deep drawing including Vacuum forming (positive and negative processes), beads, etc., realized become. With a carrier layer made of a thermoplastic or a thermoplastic fiber composite material is the plastic deformation of the carrier layer and thus the entire Lightweight composite material expediently under suitable the effect of heat carried out.

If, on the other hand, the carrier layer is made of a metal material, the plastic deformation of the carrier layer and thus the deformation of the entire lightweight composite material is preferably cold (cold forming). The effect of heat is also conceivable here as an option. Cold forming is easy with most metal materials feasible, with only titanium restrictions; Titanium can, however, be deformed superplastically, which, however, requires a not inconsiderable amount of heat and is therefore only conceivable for very thin titanium layers with regard to the processing of the material according to the invention. In the case of hot forming, it must always be ensured that the elastomer material of the fiber-elastomer composite layer is not thermally damaged.

With the method according to the invention according to claim 11 it is therefore possible the lightweight composite material according to the invention similar in its entirety like a conventional metal material or thermoplastic material to form, but especially also to form cold. Such techniques have so far not been possible with fiber composite materials. With the inventive method high-quality three-dimensional components and structures manufacture particularly easily, effectively and economically.

A preferred further advantageous embodiment the method of claim 9, 10 and 11 is the subject of the dependent claim 12th

The basis of the invention, the above task is performed according to a solved another aspect by uses as defined in claims 13 to 15.

Accordingly, a use according to the invention a lightweight composite material provided in particular according to one or more of claims 1 to 7 for a shock and / or structural component that is prone to impact and / or explosion or one Component of a missile, an aircraft, spacecraft or land vehicle or an engine for such Vehicles.

Under "impact and / or impact and / or explosion hazard" Components, structures and components are within the meaning of the invention to understand those in a practical use of the missile or Air or land vehicle with a high load due to crash, accident, flying parts (e.g. in the event of engine failure), shelling, the effects of explosive devices etc. may be exposed. at such components and structures are, for example around skin elements of spacecraft, that are at risk from space debris (radoms, pylons, Antenna fairings, other external accessories, engine shrouds and other engine turkeys, especially of turbines, tanks, Cockpit fairings, explosion-proof aircraft containers, bumpers, shock-catching Front and rear structures of automobiles, such as bonnets and trunk lid, etc.

Another use according to the invention a lightweight composite material according to one or more of claims 1 to 7 is for a floor assembly or floor assembly component of an aircraft, especially a rotary wing aircraft, especially a helicopter. Considering the The problems described at the outset and the advantages of the lightweight composite material according to the invention can significantly improve the crash behavior of the aircraft be, because the lightweight composite material according to the invention unfolds its crash-resistant properties when used particularly good.

As an example it should be mentioned that in the case of a helicopter, the tank usually arranged in the base assembly of the helicopter cell and ergo in the event of a hard emergency landing or a crash, in particular on water, particularly at risk is. Here the bursting of the tank must be prevented as far as possible become. equally However, water should also penetrate the cell or soil structure of the helicopter prevented become. Here are the positive properties of the lightweight composite material according to the invention full to carry and the crash behavior and safety of the helicopter can by the use according to the invention be significantly improved.

Another use according to the invention a lightweight composite material according to one or more of claims 1 to 8 is for a fire protection element is provided. The advantages of this use also result from those already discussed in detail at the beginning positive properties of the lightweight composite material according to the invention.

Preferred embodiments of the invention with further design details are below with reference on the attached drawings described in more detail and explained.

SHORT DESCRIPTION THE DRAWINGS

It shows:

1 a schematic cross-sectional view of a lightweight composite material according to the invention according to a first embodiment;

2 a schematic cross-sectional view of a lightweight composite material according to the invention according to a second embodiment;

3 a schematic cross-sectional view of a lightweight composite material according to the invention according to a third embodiment;

4 is a schematic cross-sectional view of an intermediate product according to the invention for producing a lightweight composite material according to the invention; and

5 is a schematic, greatly simplified and partially sectioned front view of a helicopter, which is equipped with structural components that are made of the lightweight composite material according to the invention, as an example of an inventive use of the lightweight composite material.

PRESENTATION OF PREFERRED EMBODIMENTS

In the description below and in the figures are the same to avoid repetition Parts and components also marked with the same reference symbols, unless further differentiation is required.

The 1 shows a schematic cross-sectional view of a lightweight composite material according to the invention according to a first embodiment. In its basic version, this plate-shaped or strip-shaped lightweight composite material comprises a first stretch-resistant, tensile carrier layer 2 made of a metal material (here: an aluminum alloy) and one with this carrier layer 2 firmly connected elastomer layer 4 that are essentially entirely of reinforcing fibers 6 is interspersed and a matrix for the reinforcing fibers 6 forms. As an alternative to the metal material described above, the carrier layer 2 but also be made from a composite material, such as an epoxy-aramid fiber composite, a fiber-plastic-metal composite, or the like.

The reinforcement fibers 6 interspersed elastomer layer 4 is also briefly referred to below as a fiber-elastomer composite layer 8th be designated. As an elastomer material for the fiber-elastomer composite layer 8th In the present example, acrylonitrile butadiene rubber (NBR) is used as reinforcing fibers 6 Glass fibers are used here, which, as indicated in the drawing, refer to the thickness and the longitudinal and transverse extension of the elastomer layer 4 essentially even in the elastomer layer 4 are distributed.

The backing layer 2 has a thickness of approx. 0.3 mm and the fiber-elastomer composite layer 8th a thickness of 0.7 mm. The fiber content in the fiber-elastomer composite layer 8th is approximately 55%. Basically, the fiber content in the fiber-elastomer composite layer 8th depending on the embodiment and production method in a range of about 20 to 80%, preferably 30 to 70%, more preferably 35 to 60%, the invention being not restricted to these value ranges.

In the 2 is a schematic cross-sectional view of a lightweight composite material according to the invention according to a second embodiment. This lightweight composite material has compared to the in 1 shown basic form a further, ie second rigid, tensile carrier layer 2 (also made of an aluminum alloy), and the fiber-elastomer composite layer 8th is between the first and second carrier layers 2 . 2 arranged and firmly connected to these layers. This results in a sandwich-like structure of the lightweight composite material. Although with this variant both carrier layers 2 . 2 are made of an aluminum alloy, it should be noted that the respective carrier layers 2 . 2 can in principle also be made of different materials, for example a carrier layer made of aluminum and the other made of another metal material or an epoxy-glass fiber composite or the like. The thickness of the support layers 2 . 2 in this embodiment is approximately 0.25 mm and the thickness of the fiber-elastomer composite layer 8th 1.5 mm.

3 shows a schematic cross-sectional view of a lightweight composite material according to the invention according to a third embodiment, which has a plurality of alternating carrier layers 2 and fiber-elastomer composite layers 8th has (the reinforcing fibers of the fiber-elastomer composite layers 8th are in the drawing 3 not shown separately for the sake of clarity). With a variant of this type, increased burn-through resistance and dielectric strength can be achieved, for example, with a small material thickness. The backing layers 2 have a uniform thickness of approx. 0.2 mm and the fiber-elastomer composite layers 8th uniformly a thickness of approx. 0.4 mm. The thicknesses of the respective carrier layers 2 and fiber-elastomer composite layers 8th can also differ from one another within the lightweight composite material according to the invention.

The previously explained lightweight composite materials according to the invention are for example in the form of plate or strip-shaped semi-finished products for the Manufacture of structural components provided. Under a plate or stripe shape are not just flat structures in the sense of the invention, but for example, curved ones or to understand corrugated sheet-like shapes. In addition, the lightweight composite materials according to the invention in principle also in the form of semi-finished products with open or closed cross-sectional shapes or in the form of a lightweight composite material Component available stand.

In the 4 a schematic cross-sectional view of an intermediate product according to the invention is shown, which can be used to produce a lightweight composite material according to the invention. This intermediate product comprises two unbound reinforcement fiber layers 10 For two rigid, tensile composite carrier layers of the lightweight composite material to be produced from the intermediate product, as well as one with the unbound reinforcing fiber layers 10 connected elastomer layer 4 that are essentially entirely of reinforcing fibers 6 is interspersed (fiber-elastomer composite layer 8th ). Instead of the unbound reinforcing fiber layers 10 In a further embodiment (not shown) of the intermediate product, prepreg layers can also be provided.

It will now be a first example of a procedure ren to produce a three-dimensionally shaped lightweight composite material from an intermediate 4 to be discribed. This method is preferably suitable for manual production.

A web of the intermediate product, which is cut to a desired dimension, is placed in a concave fabric, the intermediate product largely adapting to the inner contour of the mold due to its own weight. In this process, the outer, unbound reinforcing fiber layers 10 (please refer 4 ) deformed by external force (here: by the pure weight of the intermediate product itself). At the same time, the fiber-elastomer composite layer 8th elastically deformed. The reinforcing fibers follow 6 the fiber-elastomer composite layer 8th due to the elasticity of the elastomer matrix, its elastic deformation and assume a changed fiber course, that is to say the contour of the laid shape. Then the first unbound reinforcing fiber layer is placed on top of the lay-up 10 an epoxy resin is applied and the first unbound reinforcing fiber layer 10 soaked with it. Because of the fiber-elastomer composite layer 8th the epoxy resin cannot enter the second unbound reinforcing fiber layer in the lay-up 10 penetrate. By placing a film on the impregnated first unbound reinforcing fiber layer 10 and evacuating the laid mold, the intermediate product is pressed firmly against the contour of the mold. Then the applied epoxy resin is allowed to harden. The resulting molded part is already largely stable and is removed from the fabric. Then the second unbound reinforcing fiber layer 10 in an analogous manner with epoxy resin and the epoxy resin cured.

With the help of the unbound reinforcing fiber layers 10 . 10 applied and cured epoxy resin form two rigid, tensile carrier layers made of a cured, solid fiber-epoxy composite.

The elastic deformation of the elastomer layer or fiber-elastomer composite layer achieved in the process described above 8th and the changed fiber course of their reinforcing fibers 6 is maintained by means of the hardened, solid fiber-plastic composite of the carrier layers. The result is a three-dimensionally shaped component made of a lightweight composite material according to the invention.

In a second example of a method according to the invention for producing a three-dimensionally shaped lightweight composite material from an intermediate product 4 For example, the intermediate product can be machined on both sides by means of suitable application devices (ie on the unbound reinforcing fiber layers 10 . 10 be provided with resin. Provided that the intermediate product is not deformed further, but is brought into a flat state, it is possible in this way to produce plate or strip-shaped lightweight composite materials. In the present case, however, the prepared and resin-coated intermediate product is wound on a mandrel with a round cross section. Here, the unbound, but already provided with resin reinforcing fiber layers 10 deformed, wherein the effects already explained in the previous example occur with regard to the fiber-elastomer composite layer and its reinforcing fibers. After the resin has hardened, a shell-shaped or tubular component is produced from a lightweight composite material according to the invention.

In a third example of a method according to the invention for producing a three-dimensionally shaped lightweight composite material an intermediate product is used in which instead of unbound Layers of reinforcing fibers prepared prepreg layers are available. Because the prepreg layers are already provided with a resin, can be applied separately of resin are eliminated. The steps of deforming the prepreg layers and the fiber-elastomer composite layer can for example be analog to which the two method variants described above are carried out. The Harden the prepreg layers take place under the influence of heat, for example in the autoclave. The effects that occur or are achieved the same as in the previous embodiments. In the preparation of More complex three-dimensional component shapes are recommended, too to deform the prepreg layers under the influence of heat, since the prepreg layers are plastic at a suitable temperature or show some plastic properties.

A method according to the invention for processing a lightweight composite material according to the invention will now be described, as described in 2 is shown. As already mentioned, this material has two outer carrier layers 2 . 2 Made of an aluminum alloy with the fiber-elastomer composite layer 8th are glued. It is assumed that the lightweight composite material is provided in the form of a flat, plate-shaped semi-finished product. For processing, this semi-finished product is deformed by means of a stamp and a die, which are part of a pressing device, not shown. More precisely, the action of the stamp and the matrix make the two carrier layers 2 . 2 plastically deformed. This deforms the between the two carrier layers 2 . 2 arranged fiber-elastomer composite layer 8th elastic, ie it follows the deformation of the carrier layers 2 . 2 , which again in the elastomer matrix (elastomer layer 4 ) embedded reinforcement fibers 6 due to the elasticity of the elastomer matrix, a modified fiber course essentially follows the elastic deformation men. The elastic deformation of the elastomer layer caused 4 and the changed fiber course of their reinforcing fibers 6 are made by means of the plastically deformed carrier layers 2 . 2 and maintain any relaxation of the deformed elastomer matrix.

The procedure explained above is basically also for processing lightweight composite materials according to the invention suitable that over a or several carrier layers made of a thermoplastic or a thermoplastic fiber composite material feature. The plastic deformation of the carrier layer then takes place under Heat, which ensures easier deformability of the carrier layer.

Insofar as a lightweight composite material according to the invention is used in the processes explained in the context of the present description, in which the material with reinforcing fibers 6 interspersed elastomer layer 4 has a thermoplastic elastomer material, then the fiber-elastomer composite layer is preferably plastically deformed under the action of heat and then cooled. Cooling can be carried out actively with the aid of suitable coolants or passively by cooling the elastomer material itself. The deformation of the elastomer layer and the changed fiber course of its reinforcing fibers are then maintained not only by the carrier layers but also by the plastically deformed and cooled thermoplastic elastomer material itself.

The lightweight composite material according to the invention is preferred for a fire protection element and / or a shock and / or impact and / or explosion endangered Structural component or a component of a missile, an air, space or Land vehicle or an engine used for such vehicles. It is particularly suitable for a floor assembly or floor assembly component of an aircraft.

5 shows as a concrete example of use a schematic, greatly simplified and partially sectioned front view of a helicopter 12 , The cell 14 of the helicopter 12 is in their floor area where there is a fuel tank 16 is, made to a substantial extent from the lightweight composite material according to the invention. In the present case, the floor area comprises a double-walled floor element 18 , which comprises the lightweight composite material according to the invention.

The invention is not based on the above Embodiments, which is only the general explanation of the core idea of the Serve invention limited. Rather, within the scope of protection, the lightweight composite material according to the invention can also other than those specifically described above embodiments accept. The lightweight composite material can in particular have features that are a combination of the Features of the respective main claims and all or only a few Individual characteristics of the associated under claims represent. Both the backing layer as well as the fiber-elastomer composite layer of the lightweight composite material according to the invention can contain further additives which have the properties of the material according to the invention additionally influence. At the joint between a carrier layer and the fiber-elastomer composite layer or an adjoining area can Means to improve the flat Cohesion between the support layer and the fiber-elastomer composite layer be provided (e.g. in the form of adhesives, adhesives, anchors etc.).

Furthermore, the lightweight composite material according to the invention in addition to the thickness information for the carrier layer given above purely by way of example a thickness in a range from 0.1 mm to greater than 1.5 mm, in particular 0.2 mm to greater than 1 mm, and for the fiber-elastomer composite layer has a thickness of 0.2 mm to greater than 10 mm, in particular 0.8 mm to 6 mm, preferred. The total thickness of the lightweight composite can therefore, depending on the application and embodiment, between a fraction one millimeter to a few centimeters, whereby from weight reasons an overall thickness in the millimeter range is preferred.

Reference signs in the claims, the The description and the drawings serve only for a better understanding of the Invention and are not intended to limit the scope.

Designate it:

2

Carrier layer (s)

4

elastomer layer

6

Reinforcing fibers in 4

8th

Fiber-elastomer composite layer (s) 4 and 6

10

unbound Reinforcing fiber layer (s)

12

helicopter

14

cell

16

fuel tank

18

floor element

Claims (15)

Plate or shell-shaped lightweight composite material, comprising at least a first rigid, tensile carrier layer ( 2 ), which is made of at least one metal material, and at least one with this carrier layer ( 2 ) firmly connected elastomer layer ( 4 ), which is essentially entirely made of reinforcing fibers ( 6 ) is interspersed and a matrix for the reinforcing fibers ( 6 ) forms. Lightweight composite material, comprising min at least a first rigid, tensile carrier layer ( 2 ), which is made of a composite material, and at least one with this carrier layer ( 2 ) firmly connected elastomer layer ( 4 ), which is essentially entirely made of reinforcing fibers ( 6 ) is interspersed and a matrix for the reinforcing fibers ( 6 ) forms. Lightweight composite material according to claim 1 or 2, characterized in that it further comprises at least one second rigid, tensile carrier layer ( 2 ), and the at least one, essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ) between the two carrier layers ( 2 . 2 ) arranged and firmly connected to them. Lightweight composite material according to one or more of the preceding claims, characterized in that it comprises a plurality of alternating, rigid, tensile support layers ( 2 ) and essentially entirely of reinforcing fibers ( 6 ) interspersed with elastomer layers ( 4 ) having. Lightweight composite material according to one or more of the preceding claims, characterized in that the reinforcing fibers ( 6 ) which the elastomer layer ( 4 ) essentially fully enforce, based on the thickness and length and length of the elastomer layer ( 4 ) essentially uniform in the elastomer layer ( 4 ) are distributed. Lightweight composite material according to one or more of the preceding claims, characterized in that the at least one first, rigid, tensile carrier layer made of at least one metal material ( 2 ) comprises an aluminum material. Lightweight composite material according to one or more of the preceding claims, characterized in that the rigid, tensile carrier layer ( 2 ) has a thickness of 0.1 mm to greater than 1.5 mm, in particular 0.2 mm to greater than 1 mm, and that of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ) has a thickness of 0.2 mm to greater than 10 mm, in particular 0.8 mm to 6 mm. Intermediate product for producing a lightweight composite material according to claim 2, comprising at least one prepreg layer and / or at least one unbound reinforcing fiber layer ( 10 ) for the at least one first rigid, tensile composite support layer ( 2 ), and at least one with the prepreg layer or the at least one unbound reinforcing fiber layer ( 10 ) connected elastomer layer ( 4 ), which is essentially entirely made of reinforcing fibers ( 6 ) is enforced. Method for producing a three-dimensionally shaped lightweight composite material according to claim 2 by means of an intermediate product according to claim 8, which with at least one unbound reinforcing fiber layer ( 10 ) for the at least one first rigid and tensile composite support layer ( 2 ) is provided, comprising the following steps: deforming the unbound reinforcing fiber layer ( 10 ) by the action of force, and thereby - elastic deformation of the at least one, essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ), the reinforcing fibers embedded in the elastomer matrix ( 6 ) assume, due to the elasticity of the elastomer matrix, a changed fiber course which essentially follows the elastic deformation, - application of a resin-like plastic material to the unbound reinforcing fiber layer ( 10 ), - hardening of the applied resin-like plastic material, resulting in a rigid, tensile carrier layer ( 2 ) from a hardened, solid fiber-plastic composite, and maintaining the elastic deformation of the elastomer layer ( 4 ) and the changed fiber course of their reinforcing fibers ( 6 ) by means of the hardened, solid fiber-plastic composite. A method for producing a three-dimensionally shaped lightweight composite material according to claim 2 by means of an intermediate product according to claim 8, which with at least one prepreg layer for the at least one first rigid and tensile composite support layer ( 2 ) is provided, comprising the following steps: - deformation of the prepreg layer by the action of force, preferably with additional heat, and thereby - elastic deformation of the at least one, essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ), the reinforcing fibers embedded in the elastomer matrix ( 6 ) assume an altered fiber course essentially following the elastic deformation due to the elasticity of the elastomer matrix, - curing of the at least one prepreg layer under the action of heat, thereby resulting in a rigid, tensile carrier layer ( 2 ) from the hardened prepreg layer, and - maintaining the elastic deformation of the elastomer layer ( 4 ) and the changed fiber course of their reinforcing fibers ( 6 ) by means of the deformed and hardened prepreg layer. Process for processing a lightweight composite material according to one or more of claims 1 and 3 to 7, with a rigid and tensile carrier layer ( 2 ), which is made of at least one metal material, a thermoplastic or a thermoplastic fiber composite material, comprising the following steps: - plastic deformation of the at least one carrier layer ( 2 ), and thereby - elastic deformation of the at least one, essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ), the reinforcing fibers embedded in the elastomer matrix ( 6 ) assume a changed fiber course essentially following the elastic deformation due to the elasticity of the elastomer matrix, and - maintaining the elastic deformation of the elastomer layer ( 4 ) and the changed fiber course of their reinforcing fibers ( 6 ) by means of the at least one plastically deformed carrier layer ( 2 ). The method of claim 9, 10 or 11, with a substantially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ) made of a thermoplastic elastomer material, characterized in that - the essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ) plastically deformed under the influence of heat and then cooled, and - maintaining the deformation of the essentially completely of reinforcing fibers ( 6 ) penetrated elastomer layer ( 4 ) and the changed fiber course of their reinforcing fibers ( 6 ) additionally takes place through the plastically deformed and again cooled thermoplastic elastomer material. Use of a lightweight composite material according to one or more of claims 1 to 7 for a structural component or component of a missile, an aircraft, which is subject to impact and / or impact and / or explosion. 12 ), a spacecraft or land vehicle, or an engine for such vehicles. Use of a lightweight composite material according to one or more of claims 1 to 7 for a floor assembly or floor assembly component ( 18 ) of an aircraft ( 12 ). Use of a lightweight composite material after one or more of the claims 1 to 7 as a fire protection element.