DE102012205284A1 - Producing ceramic molded body useful for producing e.g. gear wheel, comprises e.g. arranging reinforcing fibers in pre-ceramic polymer matrix, molding them, winding obtained film body, and treating disk-shaped molded body with heat - Google Patents

Abstract

Producing ceramic molded body, comprises (a) arranging reinforcing fibers (20) in a pre-ceramic polymer matrix (18), (b) molding the pre-ceramic polymer matrix with the reinforcing fibers to form a film body (10), (c) winding the film body on a winding core (12), (d) fixing an end section of the film body at a position of the wound film body arranged below the film body, (e) separating at least one disk-shaped pre-ceramic molded body from the wound film body, and (f) treating the disc-shaped pre-ceramic molded body with heat. An independent claim is also included for a ceramic molded body, comprising a ceramic matrix, in which reinforcing fibers are arranged, where the ceramic molded body is disk-shaped, and the reinforcing fibers are at least partially oriented in a circular manner.

Description

The present invention relates to a ceramic molding and a method for producing a ceramic molding.

State of the art

Shaped bodies of ceramic materials are known and widely used in a wide range of applications.

From the document EP 1 685 081 B1 For example, metal-ceramic components and methods for their production are known. Such components can be used for example as brake discs and comprise a ceramic phase which is provided with a pore space which is filled with copper substantially. According to this document, a metal-ceramic component can be produced by first producing a porous ceramic preform which has a porosity of about 50% by volume and consists of inert and reactive constituents. The inert components of the precursor are formed of silicon carbide, whereas the reactive constituents are formed of titanium dioxide. The ceramic preform is a sintered body formed by sintering a green body pressed from a powder. The sintered preform is filled or infiltrated in a die casting mold with a melt of a CuAl alloy. Subsequently, the preform infiltrated with the molten metal is subjected to a controlled annealing process. The metal phase remains high-melting copper, which fills a pore space of a ceramic phase.

The document DE 10 2007 009 480 A1 describes a bicycle brake disc rigidly connected to a hub. Such a bicycle brake disc is made entirely of a composite material consisting of silicon infiltrated carbon fiber composite material. The composite material in turn preferably consists of continuous fibers with a phase distribution of greater than 60% carbon (C) and 20 to 30% silicon carbide (SiC). In addition, such a bicycle brake disc is preferably provided with a two-sided friction layer consisting of silicon carbide (SiC).

Disclosure of the invention

• a) Anordnen von Verstärkungsfasern in einer präkeramischen Polymermatrix;
• b) Formen der präkeramischen Polymermatrix mit den Verstärkungsfasern unter Ausbildung eines Folienkörpers;
• c) Aufwickeln des Folienkörpers auf einen Wickelkern;
• d) Fixieren eines Endabschnitts des Folienkörpers an einer darunter angeordneten Lage des aufgewickelten Folienkörpers;
• e) Abtrennen von wenigstens einem scheibenförmigen präkeramischen Formkörper von dem aufgewickelten Folienkörper; und
• f) Behandeln des wenigstens einen scheibenförmigen präkeramischen Formkörpers unter Einwirkung von Wärme.

The present invention is a process for producing a ceramic shaped body, comprising the process steps:

• a) arranging reinforcing fibers in a preceramic polymer matrix;
• b) forming the preceramic polymer matrix with the reinforcing fibers to form a film body;
• c) winding the film body onto a winding core;
• d) fixing an end portion of the film body to an underlying layer of the wound film body;
• e) separating at least one discoid preceramic body from the wound foil body; and
• f) treating the at least one disk-shaped preceramic molding under the action of heat.

In the context of the present invention, a ceramic molding may in particular be a body or a component which has a shape suitable for a desired field of application and which is at least partially formed from a ceramic material or which at least partially comprises a ceramic material.

For the purposes of the present invention, reinforcing fibers may be understood as meaning, in particular, fibers, ie, thin structures in relation to their length, which give the ceramic molded body increased stability and thus reinforce it.

For the purposes of the present invention, a preceramic polymer matrix may in particular be a matrix which is formed from or at least partially comprises a polymeric material which can react in a reaction step to form a ceramic material. This can be realized in particular by a thermal treatment, for example by thermal decomposition, wherein the preceramic polymer matrix, for example with exclusion of oxygen, is ceramized and thus forms a ceramic matrix.

In the context of the present invention, a film body may in particular be a body which is designed in the manner of a film and thus has a height which is small with respect to its width or depth. A film body can in particular be flexible, ie bendable.

In the context of the present invention, a winding core may in particular be any body on which a foil-like structure can be wound or rolled up. Preferably, the winding core can be designed tubular or rotationally symmetrical.

In a method described above, reinforcement fibers in the preceramic polymer matrix can thus initially be arranged in method step a). The reinforcing fibers can in particular be homogeneously distributed in the preceramic polymer matrix and do not yet have to assume a preferred orientation. This step can be realized, for example, by the incorporation and mixing of the corresponding reinforcing fibers into the polymer matrix, for example in the form of a suitable polymer melt, for example in an extruder, in a manner known to the person skilled in the art. Alternatively, in the method step a), the polymer can be liquefied by a solvent and thus the reinforcing fibers are incorporated. The solvent can be removed in this embodiment, for example, after extrusion from the polymer matrix. This step can be accelerated, for example thermally or by a particular slight vacuum.

In a next step, according to method step b), the preceramic polymer matrix can be shaped, in particular extruded, with the reinforcing fibers to form a film body. For this purpose, the polymer can be cooled, for example, when using a polymer melt in process step a) before forming, such as an extrusion process, so as to obtain a particularly advantageous moldable mass. By way of example, using a polymer solution or polymer dispersion, molding may be carried out after adjusting a suitable viscosity and the solvent removed after extrusion. On the one hand, a film body can be formed by the shaping or extrusion. This may for example have a thickness in a range of less than or equal to 1 mm. In the film body, the fibers furthermore assume a preferential orientation due to the shaping or extrusion, whereby they can be arranged substantially parallel along the extent of the film body.

The film body obtained in this way can be wound or rolled up in accordance with method step c) onto a suitable winding core. This creates a preceramic material, which is arranged in a freely selectable thickness, which may be about several centimeters, on a core. The winding can preferably be carried out using as large a force as possible or using the largest possible winding tension, but in particular the force or the winding tension is limited such that the fibers do not detach from the matrix or do not separate from the matrix. In this step, the fibers are thus conditionally arranged by the winding process in the winding direction or tangentially or they have after winding on a circular orientation. The fibers may be arranged substantially parallel. Further, a helical orientation may be included in the circular orientation.

When the film body is completely wound on the winding core, the end or the end section of the film body according to method step d) can be fixed to a location of the wound film body arranged underneath or fixed thereto. This creates a stable structure with a stable wound pre-ceramic foil body. The fixing of the film body or its end portion may depend on the exact configuration or on the materials of the film body. For example, when using a preceramic polymer having a thermally initiated crosslinking mechanism, the end region may be fixed by UV radiation, such as using an infrared radiator, or using a preceramic polymer having a UV-initiated crosslinking mechanism, particularly at the end region. It may therefore be advantageous if the preceramic polymer matrix can be exposed to a crosslinking reaction or if it comprises a crosslinking mechanism. In this case, the connection or the cross-linking can in particular be such that, in a further step, a deformation, for example in a die, is possible, as will be explained later. However, the above examples are not intended to be limiting. In principle, the film end region can also be fastened or fixed to the underlying film body layer by adhesions or suitable mechanical aids. It can be seen from the above that an attachment or fixation of the end region, although in particular takes place spatially directly on the underlying layer, but also deeper layers can be influenced or involved.

In this case, the necessary size of the end section to be fixed can in particular be variably adjustable and, for example, be dependent on the force which exists after the fixation per unit area between the end section and the film body. The lower the adhesive force per unit area, the greater the end section can be selected.

The resulting pre-ceramic film body comprising the preceramic polymer matrix with the reinforcing fibers arranged therein can now be brought into a disk-like form. This may mean in particular that a shape is formed which has a circular or substantially circular circumference and further has a small or smaller thickness in relation to the diameter. For this purpose, according to method step e), at least one disk-shaped preceramic molding can be separated from the wound-up film body. This step can be done for example by cutting or the like. For this purpose, a stiff saw blade can be used, as a particularly high planarity of the disk-shaped preceramic molding is made possible. In process step e), in one embodiment, essentially the final shape of the shaped body to be produced can thus be produced. For example, in this step, a form can be generated which can be fed directly to a later application. In this case, a disk-shaped preceramic molding or a plurality of disk-shaped preceramic molding bodies can be produced.

In order to produce a ceramic shaped body from the disk-shaped preceramic body comprising the preceramic polymer matrix with the reinforcing fibers arranged therein, the at least one disk-shaped preceramic body can be treated in accordance with process step f) under the action of heat. In this process step, which can be carried out, for example, with the exclusion of oxygen and / or at temperatures of greater than 1000 ° C., the preceramic polymer matrix ceramizes to form a ceramic material or to form the ceramic shaped body. In the thermolysis of this process step, it may be preferable to fix the preceramic or disc-shaped moldings from both sides. By such a fixation, it can be prevented that the molded bodies warp in this step or a deformation takes place. A fixation can be realized, for example, by the disc-shaped preceramic molding is placed approximately laterally on a particular porous support such as a graphite substrate, and with a particular porous support element, such as a graphite block is fixed. In this case, a fixation by the weight of the support body take place, but also other, known in the art fixations or entrapment may be possible. As a result, the ceramic shaped body produced can be fed to a corresponding application in a particularly preferred manner without any subsequent treatment.

For example, this method step can lead to a decomposition of the preceramic polymer matrix to form a ceramic, wherein in this method step only a mass loss of less than 20%, in particular less than 10%, can take place. In this case, the weight loss taking place can depend in particular on the preceramic polymers used or can be influenced by them. The achievable bandwidth can be very large. It can also be reduced by a higher fiber content of the loss of mass.

After the temperature treatment according to process step f), the ceramic molded body can be removed from the winding core so as to obtain a body which comprises the ceramic material produced from the preceramic polymer and the reinforcing fibers or which may consist of the aforementioned components.

By the method described above, a ceramic material or a ceramic molded body can be produced in a particularly advantageous manner, which can be used for a variety of applications.

According to the invention, a low porosity can also be achieved without infiltration steps or pure filtration steps of the material, since the material compresses itself during production, in particular during the thermal treatment. In detail can be achieved by winding with the highest possible winding tension that occur after the end of winding or after fixing the end portion of the film body in the winding radial forces in the direction of the winding core. These radial forces, in particular during the thermolysis, can cause the wound film body to self-compact and, without the use of external forces such as hot pressing, result in a material with very low porosity. In particular, a porosity in a range of less than or equal to 5% can be achieved.

It can be possible, in particular by a strong orientation of the fibers, a very high degree of filling of the reinforcing fibers. Thereby, the proportion of ceramic or polymer ceramic can be kept low in the molding, so that the formation of porosity, in particular during the thermal treatment in a manufacturing process for the ceramic molding is largely avoidable.

In addition to a particularly simple and cost-effective implementation of the method according to the invention can be produced by this further a ceramic molding, which may have purely by way of example directly preferred for use as a brake disc properties. As an example, an application for brake sliding of electrically driven bicycles called, at Compared to conventional bicycles, for example, there are higher average speeds and, consequently, higher demands on the brake system.

A ceramic molded body produced by a method as described above may have a low specific gravity of, for example, less than or equal to 2 g / cm ³ . As a result, substantial weight savings are possible, for example, when replacing conventional metallic brake discs. In addition, a possible decrease in the braking effect, which is also called fading, can be prevented, for example, with metallic brake disks. Also, a softening of the brake discs, which under certain circumstances can lead to a complete loss of braking force, can be counteracted.

Furthermore, as described above ceramic molded body can have a good corrosion resistance and further by a high wear resistance, high surface hardness, low abrasion and a good fracture toughness particularly high stability or a particularly long life. This can be further improved by the fact that due to a very high softening temperature, even at high temperatures, no deformation occurs. In addition to a long service life, this effect can also have a positive effect on the brake result in the case of the use of the ceramic molded body as a brake disk with regard to retarding braking, for example when driving uphill.

In addition, a ceramic molded body produced by a method according to the invention can have a good heat transfer, which is realized by a high thermal conductivity. This can be particularly high, for example, if carbon fibers or carbon-based fibers are used by way of example as reinforcing fiber. As a result, heat generated by a braking process can also be diverted particularly well when used as a brake disc, which can improve the brake result after multiple braking and / or continuous braking, for example, in comparison to conventional metallic brake discs.

The aforementioned advantages are only mentioned as examples with respect to a use of the ceramic molding as a brake disk. These advantages can also make use of a shaped article produced according to the invention particularly suitable for other fields of application.

Within the scope of one embodiment, the preceramic polymer matrix used may in particular be polycarbosilanes, polysilazanes and / or polysiloxanes or mixtures thereof. Such polymeric matrices are particularly easy to process in said process. In particular, such polymers are readily formable, such as extrudable, and can be cut well into a stable discoid preceramic body. In addition, the following ceramics, which are selected from the group consisting of silicon carbide, silicon carbonitride, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride and / or silicon nitride, can be produced in particular from the abovementioned polymers or mixtures of the abovementioned polymers. Such ceramics are characterized by a particularly high stability and longevity even at high temperatures.

Within the scope of a further embodiment, silicon carbide fibers, quartz fibers, basalt fibers, carbon fibers, carbon nanotubes, aluminum oxide fibers, zirconium oxide fibers and / or silicon nitride fibers or mixtures thereof can be used as reinforcing fibers. Such reinforcing fibers are good to produce as long fibers and also allow particularly preferred properties of the ceramic molded body produced, in particular a high stability even at high temperatures.

In the context of a further embodiment, the reinforcing fibers may have a length of greater than or equal to 1 cm. In this embodiment, in particular long fibers are used as reinforcing fibers. These can be aligned particularly advantageously, for example along the winding direction or in a circular or spiral orientation. As a result, it is possible to produce a ceramic body with a particularly ordered structure, which allows precisely defined properties which are particularly preferred in terms of stability.

As part of a further embodiment, a hollow shaft can be used as a winding core. This can in particular have a light weight and is therefore easy to handle. In addition, the resulting components can then be used particularly easily and with only a few steps, for example as a brake disc or as a gear.

• g) Formen des scheibenförmigen präkeramischen Formkörpers in einer Matrize, insbesondere unter Einwirkung von Druck.

Within the scope of a further embodiment, the method may comprise the further method step:

• g) forming the disc-shaped preceramic body in a die, in particular under the action of pressure.

In this embodiment, in particular a ceramic molded body can be generated, which has a disc-shaped structure, which does not have a strictly circular circumference, but rather, for example, at its periphery or at its side regions may be formed in a suitable manner. Such a structure is considered in the sense of the invention as substantially disc-shaped. For this purpose, step g) may preferably be carried out after the step of separating at least one discoid preceramic molding according to process step e) and before the tempering according to process step f).

In this case, a molding can be carried out, for example, by placing the disk-shaped preceramic molding or bodies in a die which has a corresponding shape. In particular, by pressing the preceramic molding can be brought into the desired shape.

In this embodiment, in particular gears can be produced by the method according to the invention. In this case, in particular, a mold or die can be used, which forms the preceramic molding such that it has tooth flanks or teeth on its circumference. Therefore, in this embodiment, in particular conventional gears replace, which are often made of metal or plastic.

Also with respect to gears, the advantages of the invention make particularly advantageous noticeable. In detail, the desired gear can be produced in a simple manner and with few manufacturing steps, which can save production costs and thus costs. For example, the annealed shaped bodies can be used directly as gears without substantial further aftertreatment and without the provision of infiltration steps, for example.

By virtue of the method according to the invention, the reinforcing fibers in the shaped body, for example in the form of a toothed wheel, can be oriented in such a way that they are always oriented in the direction of force in the mechanically particularly stressed areas, the tooth flanks. This is particularly possible because in a method described above, the fibers do not align in the flow direction during the shaping or pressing process, ie substantially radially during the entkonturnahen shaping according to step g), but aligned during molding largely perpendicular to the flow direction of the polymeric matrix stay. This may be the case in particular if the fibers have a length that is greater than the width of the tooth flanks or long fibers are used as fibers. As a result, an orientation of the fibers, which are already present in tangential form prior to shaping in accordance with step g), is made possible in the case of shaping, in particular, of toothed wheels in the teeth parallel to the tooth flanks. As a result, the reinforcing fibers can absorb the forces occurring in a later operation particularly well, which can lead to a particularly good stability of the gears thus produced.

In addition, due to the high crevice toughness and the high hardness or stability, for example, the ceramic shaped bodies produced according to the invention have a good operational stability even at high temperatures, and furthermore a significant weight saving is possible.

For example, ceramic molded bodies produced according to this embodiment can be used as toothed wheels in transmissions, for example, of electric motors, which can be designed in particular for a long service life. Exemplary applications include power tools, electric bicycles, or electric vehicles.

With regard to further advantages and technical features of the method according to the invention, reference is hereby explicitly made to the explanations in connection with the shaped body according to the invention, the use according to the invention, the figures and to the description of the figures.

The invention further relates to a ceramic molded body comprising a ceramic matrix, are arranged in the reinforcing fibers, wherein the shaped body is configured disc-shaped and the reinforcing fibers are at least partially aligned in a circle. Such a shaped body can be produced in particular by the method described above. It has a particularly high long-term stability even at elevated temperatures and can be exposed to high loads in a wide variety of applications. For example, a shaped body according to the invention can be used as a brake disk or as a toothed wheel. In particular, as a gear, the reinforcing fibers are present in the interior of the molding in a circular shape, whereas they can be present at the periphery, in particular along the tooth flanks, substantially parallel to these.

In one embodiment, the ceramic matrix may be selected from the group consisting of silicon carbide, silicon carbonitride, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride and / or silicon nitride or mixtures thereof. This can be realized in particular by the choice of a suitable preceramic polymer or by the choice of a plurality of preceramic polymers. Reinforcing fibers may be selected from the group consisting of silicon carbide fibers, quartz fibers, basalt fibers, carbon fibers, carbon nanotubes, alumina fibers, zirconia fibers and / or silicon nitride fibers, or mixtures thereof. A shaped body with such constituents can be produced particularly simply by the method according to the invention and furthermore has particularly good stability properties and weight properties even at high temperatures.

Within the scope of a further embodiment, the reinforcing fibers can be present in an amount of greater than or equal to 1% by volume to less than or equal to 40% by volume. In particular, with such a high degree of filling, the proportion of ceramic or polymer ceramic can be kept low in the molding, so that the formation of porosity, in particular during the thermal treatment in a manufacturing process for the ceramic molding is largely avoidable. This refinement can thus lead to improved properties, in particular with regard to heat transport and the stability behavior.

With regard to further advantages and technical features of the shaped body according to the invention, reference is hereby explicitly made to the explanations in connection with the method according to the invention, the use according to the invention, the figures and the description of the figures.

The present invention furthermore relates to the use of a method according to the invention and / or of a ceramic molding according to the invention for producing a brake disk or a toothed wheel. For example, a method according to the invention can be used to produce brake disks for electrically driven bicycles. Furthermore, the method according to the invention can be used to produce gears, in particular for transmissions of electric motors. These are particularly long-term stability even at high temperatures and can thereby weight savings compared with conventional brake discs or gears, which are based on metallic components, for example.

With regard to further advantages and technical features of the use according to the invention, reference is hereby explicitly made to the explanations in connection with the shaped body according to the invention, the method according to the invention, the figures and the description of the figures.

With regard to further advantages, reference is made to the above statements regarding the method according to the invention and the shaped body according to the invention.

Drawings and examples

Further advantages and advantageous embodiments of the subject invention are illustrated by the drawings and explained in the following description. It should be noted that the drawings have only descriptive character and are not intended to limit the invention in any way. Show it

1a a schematic view of a winding core obliquely from above with attached film body;

1b a schematic view of a winding core obliquely from above with largely wound film body;

1c a schematic view of a winding core from the side with fully wound film body;

2 a schematic view obliquely from the side showing a winding core with fully wound film body;

3 a schematic view obliquely from the side of a disk-shaped molding;

4 a die before and after the molding of the molding; and

5 an enlarged partial view of 4 ,

In 1 is shown part of the method according to the invention. According to 1 becomes a film body 10 on a winding core 12 , such as a hollow shaft, wound up. For this purpose, the winding core in the direction of the arrow 14 be rotated.

The film body 10 is producible by reinforcing fibers 20 in a preceramic polymer matrix 18 are arranged and the preceramic polymer matrix 18 with the reinforcing fibers 20 under formation of a film body 10 shaped, in particular extruded be. As preceramic polymer matrix 18 For example, polycarbosilanes, polysilazanes and / or polysiloxanes can be used. Alternatively or additionally, as reinforcing fibers 20 Silicon carbide fibers, quartz fibers, basalt fibers, carbon fibers, carbon nanotubes, alumina fibers, zirconia fibers and / or silicon nitride fibers. Furthermore, the reinforcing fibers 20 have a length greater than or equal 1 cm, but it is not excluded in the context of the present invention that as reinforcing fibers 20 Short fibers with a length of less than or equal to 1 cm or endless fibers can be used.

1a) shows the beginning of winding when the film body 10 not yet wound up but only at the hub 12 can be fixed, such as by gluing, mechanical aids or other, the skilled person basically known measures, and 1b) further shows a state in which the film body 10 largely on the winding core 12 is wound up, so that on the winding core 12 a tube is formed from the extruded and wound material in which the reinforcing fibers 20 are aligned substantially circular. Further shows 1c) a state in which an end portion 11 of the film body 10 to an underlying layer of the wound film body 10 is fixed, as is the arrow 15 in 1b) should represent.

2 shows a view obliquely from the side of a completely on a winding core 12 rolled or wound and fixed film body 10 ,

Based on the process state according to 1c) respectively 2 , At least one disc-shaped preceramic molding 16 from the wound-up film body 10 be separated. A separated disk-shaped preceramic molding 16 is in 3 shown. This preceramic molding 16 can be subsequently treated under the action of heat to form a ceramic shaped body. Depending on the preceramic polymer matrix used, the ceramic molding body may comprise a ceramic matrix which is selected from the group consisting of silicon carbide, silicon carbonitride, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride and / or silicon nitride.

A ceramic shaped body produced in this way thus comprises a polymer ceramic-based fiber-reinforced material as a ceramic matrix in which reinforcing fibers 20 are arranged, wherein the ceramic molded body is configured at least partially disc-shaped and the reinforcing fibers 20 are aligned at least partially circular. This shaped body can be used, for example, as a brake disk. For this, the ceramic material of the winding core 12 be separated.

The disc-shaped ceramic molded body may have a thickness of, for example, greater than or equal to 2 mm to less than or equal to 20 mm, for example for use as a gear wheel. For use as a brake disc, for example, a thickness of greater than or equal to 3 mm may be advantageous.

In particular, when using the ceramic molding as a brake disc holes can be introduced into these, preferably before the temperature treatment. This step can be realized for example by drilling, milling, punching, laser cutting. Subsequently, the perforated disk-shaped body can be subjected to a temperature treatment.

In 4 a further optional process step is shown. This includes molding the discoid preceramic body 16 in a mold 22 , in particular under the action of pressure. Show 4a an empty stencil 22 and 4b) a matrix with inserted preceramic disc-shaped molding 16 , In this are the reinforcing fibers 20 in the polymer matrix 18 in particular completely circular or substantially circular.

4c) shows the shaped body 16 in the mold 22 after a molding. In 4c) or in 5 , which an enlarged view of the molding according to 4c represents, it can be seen that the reinforcing fibers 20 in interior, so at least partially, are aligned in a circle. The reinforcing fibers 20 are not interwoven in this area, but in the polymer matrix 18 aligned in parallel. Along the circumference are the reinforcing fibers 20 however, along the in the matrix 22 shaped tooth edges 24 aligned.

In this embodiment, the method according to the invention can thus be suitable, for example, for producing gears, for example for electric motors.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1685081 B1 [0003]
• DE 102007009480 A1 [0004]

Claims (10)

A method for producing a ceramic shaped body, comprising the method steps: a) arranging reinforcing fibers ( 20 ) in a preceramic polymer matrix ( 18 ); b) shaping the preceramic polymer matrix ( 18 ) with the reinforcing fibers ( 20 ) to form a film body ( 10 ); c) winding up the film body ( 10 ) on a winding core ( 12 ); d) fixing an end section ( 11 ) of the film body ( 10 ) at an underlying layer of the wound film body ( 10 ); e) separating at least one disk-shaped preceramic molding ( 16 ) of the wound film body ( 10 ); and f) treating the at least one discoid preceramic body ( 16 ) under the influence of heat. Process according to claim 1, wherein as preceramic polymer matrix ( 18 ) Polycarbosilanes, polysilazanes and / or polysiloxanes or mixtures of the aforementioned materials can be used. Method according to one of claims 1 or 2, wherein as reinforcing fibers ( 20 ) Silicon carbide fibers, quartz fibers, basalt fibers, carbon fibers, carbon nanotubes, alumina fibers, zirconia fibers and / or silicon nitride fibers, or mixtures thereof. Method according to one of claims 1 to 3, wherein the reinforcing fibers ( 20 ) have a length greater than or equal to 1cm. Method according to one of claims 1 to 4, wherein as a winding core ( 12 ) a hollow shaft is used. Method according to one of claims 1 to 5, comprising the further process step: g) molding the discoid preceramic body ( 16 ) in a die ( 22 ), in particular under the action of pressure. Ceramic molded body comprising a ceramic matrix in which reinforcing fibers ( 20 ) are arranged, wherein the shaped body is configured disk-shaped and the reinforcing fibers ( 20 ) are aligned at least partially circular. Shaped body according to claim 7, wherein the ceramic matrix is selected from the group consisting of silicon carbide, silicon carbonitride, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride and / or silicon nitride or mixtures thereof, and / or wherein the reinforcing fibers ( 20 ) are selected from the group consisting of silicon carbide fibers, quartz fibers, basalt fibers, carbon fibers, carbon nanotubes, alumina fibers, zirconia fibers and / or silicon nitride fibers, or mixtures thereof. Shaped body according to claim 7 or 8, wherein the reinforcing fibers ( 20 ) are present in an amount of greater than or equal to 1% by volume to less than or equal to 40% by volume. Use of a method according to one of claims 1 to 6 and / or of a ceramic shaped body according to one of claims 7 to 9 for producing a brake disc or a toothed wheel.

Images