DE102018129162A1 - Process for producing a component from metal or materials from technical ceramics - Google Patents

Abstract

A method for producing a component from materials of technical ceramics or sintered metallurgical materials is proposed, with the following steps: First, a mixture of a binder and a ceramic or sintered metallurgical granulate is produced (100). This mixture must be suitable for the additive manufacturing of a green body from the mixture. If the mixture is available, a green body is produced by means of additive manufacturing (110). This is then isostatically compressed again in the green state or in a fully or partially debindered state or in a slightly sintered state (150). The post-compacted component is then sintered (180). By increasing the density before the actual sintering process (180) and the additional homogenization of the density distribution through isostatic pressing (150), higher sintered densities and significantly improved property values with regard to strength and other parameters can be achieved in the subsequent sintering process.

Description

Field of the Invention

Nowadays, products made from technical ceramics can achieve very good and reproducible strength values and other properties that enable the use of ceramic components in mechanical engineering, medical technology or other areas of application.

Component properties at the upper limit of the values that are possible today can usually be achieved in ceramic components by producing and using ceramic powders with high chemical purity and with a particularly small crystallite size. These powders are processed into a green body with the lowest possible binder content under high pressures. One goal is to maintain a high green density and, due to the low binder content (<5%), to create as few or small pores as possible during the subsequent debinding.

Despite a higher content of organic binders, high-quality components can also be produced using the injection molding process if the pressure during injection molding is correspondingly high.

Processes such as uniaxial pressing or cold isostatic pressing are preferably used to produce such high-quality ceramic components.

With uniaxial pressing, the pressing pressure is only exerted on the body in one direction. Uniaxial pressing requires a lot of tools.

Isostatic pressing is a pressing process in which the pressing pressure acting on the component is the same in all directions. The isostatic process uses an elastic cover around the green body. Depending on the geometry, further processing of this compact by turning or milling is usually necessary. In the case of small batch sizes, mainly cylindrical molds are used as molds for the pressing process, since geometrically optimized molds would require additional mold construction. Due to this mostly rough preform, depending on the geometry of the desired component, a relatively high "machining effort" is required, which leads to corresponding losses of the ceramic powder material used.

Additive manufacturing processes, in particular various 3D printing processes, have been developed for the material classes plastic and metals in recent years until they are ready for series production. With these processes, both customer-specific individual parts (e.g. crowns and bridges made of CrCo alloys in the dental field) and sample parts ("fast prototyping") can be manufactured in one-off production.

For some time now, attempts have been made to establish the 3D printing process for the ceramic material class with a large number of different manufacturing processes. Examples include the lithography process (LCM), the suspension-based process DLP, the thermoplastic printing T3DP, the powder-based process (binder jetting), the selective laser sintering (SLS), the fused filament fabrication process (FFF).

With additive 3D processes for ceramic materials, as with metallic or thermoplastic materials, highly complex structures can be produced that cannot be realized with other production processes.

The bodies made of ceramic materials produced in the 3D printing process have to be further processed by sintering at suitable higher temperatures with a corresponding volume shrinkage. An exception to this are components made of silicon-infiltrated silicon carbide (SiSiC), also called reaction-bonded silicon carbide (RbSiC). These parts no longer experience any significant shrinkage during the actual sintering process, since the pores present after debinding are filled with molten silicon.

The 3D printing of components leads to problems during the subsequent sintering, because on the one hand the high proportion of binder (from 20 - 40% by volume) can only be expelled very slowly and the raw body remaining after debinding has a correspondingly high proportion of pores. Debinding which is too fast can lead to crack formation during this process if the resulting gases from the debinding process cannot be discharged sufficiently quickly from the inside of the component through the molded body to the outside. Due to the high pore content after debinding, the component cannot be sintered during the subsequent sintering or only to a very limited extent to a homogeneous body with a very high density. Sintering densities of> 99% are required to achieve the best possible property values. Typical defects are crack formation due to rapid debinding or low mechanical parameters in the sintered state due to residual porosity. This effect occurs with 3-D printed ceramic components, the greater the wall thickness of the manufactured component.

The mechanical properties in the sintered ceramic final state of the components produced by means of the 3D printing process are below the customary values of high-performance ceramics required and required for a technical application as mechanical components, which are achieved with the conventional production processes mentioned above.

These considerations apply equally to components made of oxide-ceramic materials and to components made from non-oxide materials. Typical representatives of oxide ceramics include aluminum oxide Al ₂ O ₃ in various degrees of purity, zirconium oxide ZrO ₂ with various stabilizing additives and the mixed materials ATZ (alumina toughened zirconia) or ZTA (zirconia toughened alumina). SSiC (Sintered Silicon Nitride) and Si ₃ N ₄ (Sintered Silicon Nitride) may be mentioned here as representatives of the non-oxide ceramics, each in different degrees of purity and phase modifications as well as with different sintering additives.

In the 3D printing process of ceramic materials, the powdery raw materials must be mixed with various additives in order to enable the respective printing process. The thermoplastic processes T3DP and FFF require particularly high proportions of additives. In the lithography process, due to the low binder content according to the literature, green densities of up to 55% and thus sintered densities of 99.4% are achieved. With other methods, these values are significantly lower.

In all known additive manufacturing processes, the ceramic powder is always brought into the desired shape without pressure or at low pressure. In combination with the high proportion of (mostly organic) additives, the production without external pressure after debinding of the manufactured components leads to a structure with a relatively high pore content and a low green density. These green bodies with a relatively low green density have a relatively high proportion of pores and can subsequently not or only to a very limited extent be processed into a ceramic body with a very high sintered density and very good mechanical properties.

Most other ceramic manufacturing processes (uniaxial pressing, isostatic pressing, high pressure casting, injection molding, etc.) work with high pressures during shaping and the lowest possible proportion of organic binders in order to achieve high sintered densities, a homogeneous and fine crystalline structure and good mechanical properties after the sintering process to reach.

in the 3D Printing processes with ceramic materials are mostly produced filigree and thin-walled components. The components often also have internal structures that cannot be produced by other processes. The wall thicknesses range from 0.5 mm to a maximum of 6 mm.

In contrast to the ceramic components that can already be produced using 3D printing processes, relatively solid components with wall thicknesses over 6 mm are required for many applications. These components are usually relatively solid and are in the size range from 20 x 20 x 20 mm to 300 x 300 x 300 mm. There are no complex internal structures, but the wall thicknesses range from 6 to 35 mm.

State of the art

Such solid ceramic parts are produced in the prior art by isostatic pressing of the raw powder and subsequent processing of the green body on lathes and milling machines. Then debinding and sintering take place with a linear shrinkage of about 20%. In the hard-fired state, grinding is usually still required to achieve the required tolerances and surface qualities. Due to the machining of an isostatically pressed solid body required in such a conventional manufacture of a ceramic machine component, depending on the geometry, up to 80% of the ceramic material has to be removed and disposed of.

In the US 2018/104743 A1 the sintered powder is compressed by controlled pressure waves that are generated by actuators.

In the EP 1 534 461 B1 a 3D object is used to build a metallic object without the addition of a binder. Compaction is achieved when the component is built up in layers by compressing each layer with a pressure roller.

EP 1 292 413 B1 shows an alternative solution for sintered parts with 98-99% of the theoretical maximum density by adding sugar to the sinter powder in connection with a special process.

task

The object of the invention is to provide a method which enables the production of solid components made of metal or materials of technical ceramics with sintered densities above 99%.

solution

This object is solved by the subject matter of the independent claim. Beneficial Developments of the subject matter of the independent claim are characterized in the subclaims. The wording of all claims is hereby incorporated by reference into the content of this description.

The use of the singular is not intended to exclude the majority, which must also apply in the opposite sense, unless the contrary is disclosed.

Individual process steps are described in more detail below. The steps do not necessarily have to be carried out in the order given, and the method to be described can also have further steps not mentioned.

To solve the problem, a method with the following steps is proposed: First, a mixture of a binder and a ceramic or sintered metallurgical powder is produced. This mixture must be suitable for the additive manufacturing of a green body from the mixture. If the mixture is available, a green body is created by means of additive manufacturing. This is then isostatically compressed to achieve a more homogeneous density distribution and a higher green density. The redensification can take place in the green state or in partially or completely debindered or in a slightly sintered state. Then the densified component is sintered.

I.e. In order to achieve the goal of increasing the green density and reducing the porosity after the sintering process, green bodies produced according to the invention are post-compressed using an isostatic pressing process before the sintering process.

• - Durch die Erhöhung der Dichte vor dem eigentlichen Sinterprozess sowie die durch das isostatische Pressen zusätzlich erfolgende Homogenisierung der Dichteverteilung lassen sich im anschließenden Sinterprozess höhere Sinterdichten und deutlich verbesserte Eigenschaftswerte bezüglich Festigkeit und weiterer Parameter erreichen. Dies gilt im Besonderen für die (Biege-bruch-)Festigkeit und daraus resultierende Werte wie z.B. die Temperaturschockbeständigkeit.
• - Die additive Fertigung ermöglicht eine sehr exakte und materialsparende Herstellung des Grünkörpers. Durch die additive Fertigung wird eine endkonturnahe Herstellung des Rohkörpers möglich und entsprechend weniger Material verbraucht.
• - Durch das zusätzliche Nachverdichten vor dem Sinterprozess werden die Werkstoffeigenschaften der Bauteile verbessert.
• - Das bei konventioneller Herstellung nötige spanende Abtragen von bis zu 80% des Materials wird vermieden.
• - Im Stand der Technik sind die mechanischen Kennwerte von mittels 3D-Druck Verfahren hergestellter Keramik-Bauteile schlechter als die Werte von konventionell gefertigten Keramik-Bauteilen. Dies ist unter anderem auf eine größere Porosität zurückzuführen. Diesem Nachteil wird durch die erfindungsgemäße Weiterbehandlung der in additiver Fertigung hergestellten Grünkörper abgeholfen.
• - Durch den Einsatz des isostatischen Pressverfahrens entfällt die aufwändige Herstellung von spezifischen Presswerkzeugen für uniaxiales Pressen.

The process offers a number of advantages:

• - By increasing the density before the actual sintering process and the homogenization of the density distribution, which is additionally achieved by isostatic pressing, higher sintered densities and significantly improved property values with regard to strength and other parameters can be achieved in the subsequent sintering process. This applies in particular to the (flexural strength) and the resulting values such as the resistance to temperature shock.
• - The additive manufacturing enables a very precise and material-saving production of the green body. The additive manufacturing enables a near-net-shape production of the raw body and accordingly less material is used.
• - The additional material densification before the sintering process improves the material properties of the components.
• - The machining removal of up to 80% of the material required in conventional production is avoided.
• - In the prior art, the mechanical characteristics of ceramic components produced by means of 3D printing processes are worse than the values of conventionally manufactured ceramic components. This is due, among other things, to greater porosity. This disadvantage is remedied by the further treatment according to the invention of the green bodies produced in additive manufacturing.
• - The use of the isostatic pressing process eliminates the time-consuming production of specific pressing tools for uniaxial pressing.

With the method according to the invention, components can be produced efficiently from materials of technical ceramics or sintered metals. These include e.g. Valve body, valve cone seat rings, valve balls, wear protection sleeves or the like for process control.

Isostatic pressing is preferably carried out in the form of nasostatic pressing. In order to protect the body produced in an additive process during the recompression from the penetration of the liquid pressure medium during the nasostatic pressing, it is preferably coated with an elastic sleeve in a watertight manner before the nasostatic pressing.

This can be done in a particularly simple manner by means of a plastic sleeve that is evacuated. Commercial vacuuming methods are available for this purpose, by means of which the green body can be welded in a film in a watertight manner. The vacuum process is widely used in food technology, but can also be used for technical objects.

If the component to be manufactured is ring-shaped or tubular, the elastic sleeve must be designed as a double-walled hose.

Alternatively, the green body produced in an additive process can be coated with an expandable lacquer prior to isostatic pressing. Elastic paints based on plastics (e.g. polyurethane-based paints) are particularly suitable for this. The difficult assembly of elastic (usually reusable) sleeves can then be omitted. Such painting can be done in a simple immersion process.

To prevent the varnish from carbonizing or burning during sintering and producing soot and smoke, which could affect the component, the varnish is preferably removed before sintering. This is preferably done by chemical dissolving.

To improve the homogeneity and density of the component, the green body is preferably at least partially debinded after the additive manufacturing and before the isostatic post-compression. The binder is preferably removed almost completely.

In order to further increase the homogeneity and density of the component, the component can be deblocked a second time and further after compression, but before sintering.

Before sintering, this varnish will be removed again by pyrolysis or by means of a solvent. Depending on the type of paint used, water or organic solvents are suitable as solvents. The varnish is preferably removed by thermal treatment between 20 ° C and 650 ° C. In principle, this process corresponds to the "debinding" of the plasticizer / binder of the ceramic green body that has already been carried out. Debinding must, however, be carried out much more slowly, since the resulting gases have to escape from the component through very small pore channels, while the coating is only on the surface.

1. a) die Außenkanten des Bauteils können Radien aufweisen;
2. b) die Folien sind dick genug und ausreichend dehnungsfähig, um an Kanten geschlossen zu bleiben;
3. c) der dehnungsfähige Lack wird ausreichend dick aufgetragen;
4. d) der Lackauftrag erfolgt an den Kanten dicker; oder
5. e) es werden eine zweite Schicht Lack aufgetragen oder zwei elastische Hüllen übereinander eingesetzt.

Es ist auch denkbar, die Lage des Bauteils in der vakuumierten und verschweißten Folie derart zu optimieren, dass möglichst keine Ecken in die Folie ragen.The following measures can be taken to prevent the welded film or lacquer from tearing at the edges of the component during isostatic pressing:

1. a) the outer edges of the component can have radii;
2. b) the films are thick enough and stretchable enough to remain closed at the edges;
3. c) the stretchable varnish is applied sufficiently thick;
4. d) the paint is applied thicker at the edges; or
5. e) a second layer of lacquer is applied or two elastic covers are used one above the other.

It is also conceivable to optimize the position of the component in the vacuum-sealed and welded film in such a way that as far as possible no corners protrude into the film.

When the ceramic green body is heated, the organic binders are driven out or oxidized and driven out in the range between room temperature and about 600 ° C. The component does not change its external shape, but is made easier by the escape of the substances. This reduces the macroscopic density of the body and creates a pore volume. The actual sintering process begins through liquid phase formation or solid-state diffusion only at a higher temperature (depending on the material) of around 800 - 1,000 ° C. During this sintering process, the entire body becomes smaller (ceramic shrinkage) and the pore volume is reduced. The macroscopically measurable density of the body increases. If one stops this sintering process shortly after the onset of shrinkage, one speaks of sintering.
When debinding and sintering, the ceramic component always has a state in which organic binder components have been completely expelled, but there is still no firm ceramic bond. Nevertheless, the component does not fall apart in the firing process.

The object is also achieved by a component which was produced using the method described and which has a pore fraction of less than 1% of the volume after sintering.

If the coating remains at least partially on the component, the remaining coating can enable or improve a function of the component, in particular due to a hydrophilic or oleophilic or electrically conductive or electrically insulating property of the coating.

The method described is suitable, among other things. for the production of wear protection sleeves, valve seat rings, valve bodies or valve housing parts.

Further details and features emerge from the following description of preferred exemplary embodiments in conjunction with the figures. The respective features can be implemented individually or in combination with one another. The possibilities for solving the task are not limited to the exemplary embodiments. For example, range specifications always include all - not mentioned - intermediate values and all conceivable subintervals.

• 1A einen Ablaufplan des vorgeschlagenen Verfahrens;
• 1B einen Ablaufplan des vorgeschlagenen Verfahrens;
• 2 eine Verschleißschutzhülse;
• 3 einen Sitzring für eine Kugel;
• 4 eine Kugelumlaufhülse; und
• 5 eine Verschleißschutzhülse.

An embodiment of the method according to the invention is shown schematically in the figures. In detail shows:

• 1A a flowchart of the proposed procedure;
• 1B a flowchart of the proposed procedure;
• 2nd a wear protection sleeve;
• 3rd a seat ring for a ball;
• 4th a recirculating ball sleeve; and
• 5 a wear protection sleeve.

The 1A and 2 B show two preferred processes of the proposed method for producing a component from, for example, a technical ceramic.

In step 100 a mixture of a binder and a ceramic or sintered metallurgical granulate is produced.

• - Filamente oder Pellets für Extrusionsverfahren
• - Pulver für Schmelzverfahren
• - Resin (Harz) & Wachs für Druckverfahren mit flüssigen Materialien

Als Binder zur Herstellung des jeweiligen Vormaterial für die verschiedenen 3D-Druck Verfahren werden unter anderem folgende Polymere und Thermoplaste verwendet:

• - ABS (Acrylnitril-Butadien-Styrol)
• - PLA (Polyactide - polyactid acid) - Polymilchsäure
• - Nylon (Polyamid)
• - PC (Polycarbonat)
• - PP (Polypropylen)
• - PVA (Polyvinylalkohol)
• - TPE (Thermoplastische Elastomere)
• - XT-Copolyester

Die Liste ist nicht vollständig, andere Polymere und Thermoplaste sind ebenfalls möglich.Depending on the process used, different processing forms of the ceramic raw material and the binder system are required for "3D printing":

• - Filaments or pellets for extrusion processes
• - Powder for melting processes
• - Resin (resin) & wax for printing processes with liquid materials

The following polymers and thermoplastics are used as binders for the production of the respective primary material for the various 3D printing processes:

• - ABS (acrylonitrile butadiene styrene)
• - PLA (polyactide - polyactid acid) - polylactic acid
• - nylon (polyamide)
• - PC (polycarbonate)
• - PP (polypropylene)
• - PVA (polyvinyl alcohol)
• - TPE (thermoplastic elastomers)
• - XT copolyester

The list is not exhaustive, other polymers and thermoplastics are also possible.

In step 110 a green body is then made additively from the mixture. At this stage, the green body often has about 50 +/- 15% of the maximum achievable density of the ceramic end material.

In step 120 the binder is wholly or partly removed from the green body by pyrolysis or another process. When the ceramic green body is heated, the organic binders are driven out or oxidized and driven out in the range between room temperature and about 600 ° C. The component does not change its external shape, but is made easier by the escape of the substances. This reduces the macroscopic density of the body and creates a pore volume. The actual sintering process begins through liquid phase formation or solid-state diffusion only at a higher temperature (depending on the material) of around 800 - 1,000 ° C. During this sintering process, the entire body becomes smaller (ceramic shrinkage) and the pore volume is reduced. The macroscopically measurable density of the body increases. If one stops this sintering process shortly after the onset of shrinkage, one speaks of sintering.
When debinding and sintering, the ceramic component always has a state in which organic binder components have been completely expelled, but there is still no firm ceramic bond. Nevertheless, the component does not fall apart in the firing process.

In step 130 the green body is sintered slightly in order to stabilize it further. Whether a thermal process step is required between the production of the green body by one of the various additive processes and the post-compression of the component by isostatic pressing and how far the body should be debinded or even sintered depends on the type of 3D printing process chosen and the residual porosity still present in the green body and the type of binder and plasticizer system used. You cannot specify a fixed number for a residual volume share of binder here. The redensification takes place in the green state or in partially or completely debindered or in a slightly sintered state.

In step 140 respectively. 145 the green body is packed or coated watertight. This can be done by vacuuming 145 in a suitable plastic film (made of PE or PP or other plastics) or by immersion 140 in a suitable varnish. This coating is intended to prevent the hydraulic fluid from penetrating into the pores. This is typically done using varnishes based on elastic plastic that shows no cracking, such as varnishes based on polyurethane. The stretchable varnish is applied sufficiently thick. The paint is applied thicker at the edges, which prevents the paint layer from tearing open during subsequent isostatic compaction. The thicker application of paint on unbroken edges is set automatically if the application of paint is carried out in the dipping process. This coating process also enables the isostatic pressing of bodies with finer inner contours or (transverse) bores.

In step 150 this is followed by a cold, nasostatic pressing of the green body with a hydraulic fluid. After pressing, the green body usually has a density of approximately 55 +/- 15% of the maximum achievable density of the ceramic end material.

In step 160 the waterproof covering is removed. This can be done by using a coating or a varnish by pyrolysis or by means of a solvent, with vacuumed blanks the covering can be removed mechanically.

In step 170 the green body is further released. This is done either by pyrolysis or by means of a solvent.

In step 180 the green body is finally sintered. The component should preferably have a density of more than 98% of the maximum achievable density of the ceramic end material.

In step 190 If necessary, the surfaces are subsequently finished, for example by grinding, sandblasting or machining.

• 2 eine Verschleißschutzhülse;
• 3 einen Sitzring für eine Kugel;
• 4 eine Kugelumlaufhülse; und
• 5 eine Verschleißschutzhülse.

The 2nd to 7 show examples of components that can be produced with the proposed method. The parts are relatively thick-walled, and their production with conventional machining would result in considerable material losses due to the shape. In detail shows:

• 2nd a wear protection sleeve;
• 3rd a seat ring for a ball;
• 4th a recirculating ball sleeve; and
• 5 a wear protection sleeve.

glossary

additive manufacturing

Additive manufacturing, also popularly known as 3D printing, refers to processes for manufacturing components by means of point or layered construction. The production takes place on the basis of computer-aided models of the components made of formless (liquids, gels / pastes, powder etc.) or form-neutral (band, wire, sheet) material by means of chemical and / or physical processes.

binder

Binder or binder are substances that adhere added solids with a fine degree of division (e.g. powder). Binders are usually added to the fillers to be joined in liquid or pasty form. Both substances are mixed intensively so that they are distributed evenly and all particles of the filler are evenly wetted with the binder.

FFD (Fused Feedstock Deposition) process

The main difference from the FFF process is that instead of filaments, granules are used as the raw material. This means that commercially available raw materials from the injection molding sector can be used.

Fused filament fabrication

Fused Filament Fabrication, or FFF for short, is a 3D printing process that uses an endless filament made of a thermoplastic material. A large spool feeds it through a movable, heated printer extruder head. Melted material is pressed out of the nozzle of the print head and placed on the growing workpiece. The head is moved under computer control to define the printing form. Typically, the head moves in layers, moving in two dimensions to deposit one horizontal plane at a time, before moving up slightly to start a new disk. In the FFF process, ceramic or sintered metallurgical powder has to be introduced into a filament beforehand. By inserting it into a plasticizing filament, almost all ceramic materials can be processed. Relatively simple and inexpensive printing machines can be used.

Green body

In the manufacture of sintered workpieces, a green body or green body is an unsintered blank that can still be processed. For example, it is powder bonded with binders. The green bodies are dimensioned in such a way that they almost get their final shape through the shrinkage when burning.

Isostatic post-compression or pressing

Isostatic post-compression is a pressing process in which the pressing pressure acting on the component is the same in all directions. This method is well suited for small parts with high isotropy and uniform compression, and is also favorable for demanding prototypes and production in small series.

Nasostatic post-compression or pressing

Nasostatic post-compression is isostatic post-compression, in which the pressure is transmitted through a liquid, preferably through water. The form enveloping the compact is completely immersed in the pressure medium (e.g. water) immersed and removed from the print medium for demolding.

D- extrusion process

In the 3D extrusion process, the plastic ceramic mass is pressed through an extruder through a 3D movable nozzle.

cited literature

cited patent literature

• US 2018/104743 A1
• EP 1 534 461 B1
• EP 1 292 413 B1

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included 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.

Patent literature cited

• US 2018104743 A1 [0020, 0066]
• EP 1534461 B1 [0021, 0066]
• EP 1292413 B1 [0022, 0066]

Claims (15)

Method for producing a component from metal or materials from technical ceramics with the following steps: 1.1 producing (100) a mixture of a binder and a ceramic or sintered metallurgical granulate; 1.2 additive manufacturing (110) of a green body from the mixture; 1.3 isostatic redensification (150) of the green body; and 1.4 Sintering (180) of the green body which is post-compressed isostatically. Method according to the preceding claim, characterized in that 2.1 nassostatic post-compression is used for the isostatic post-compression (150); and 2.2 that the green body is encased in a watertight manner with an elastic sleeve before the nasostatic post-compression (150). Method according to the preceding claim, characterized in that 3.1 the elastic cover is a plastic cover; and 3.2 that the plastic casing is evacuated before the nasostatic post-compression (150). Method according to the preceding claim, characterized in that the elastic sleeve is designed as a double-walled hose for annular or tubular components. Procedure according to Claim 1 or 2nd , characterized by painting (140) the green body before the isostatic pressing (150) with an elastic paint. Method according to the preceding claim, characterized by removing (160) the lacquer before sintering. Method according to one of the preceding claims, characterized by at least partial debinding (120) of the green body after the additive manufacturing (110) and before the isostatic post-compression (150). Method according to one of the preceding claims, characterized by debinding (170) of the green body before sintering. Method according to one of the two preceding claims, characterized in that the debinding (120, 170) is carried out by pyrolysis or by means of a solvent. Procedure according to one of the Claims 2 to 9 , characterized , 10.1 that the component is manufactured additively such that edges of the component have radii; and / or 10.2 that the varnish or the elastic casing is thick enough and sufficiently stretchable to remain closed on edges during the naso-static re-compaction (150); and / or 10.3 that the paint application (140) is thicker at the edges than on the surfaces of the at least partially debindered green body; and / or 10.4 that two layers of lacquer or two elastic covers are used one above the other. Method according to one of the preceding claims, characterized in that the green body is sintered (130) before the isostatic post-compression (150). Method according to one of the preceding claims, characterized in that the additive manufacturing (110) takes place in the fused filament fabrication method. Component manufactured according to one of the preceding claims, characterized in that after sintering the proportion of pores in the component is less than 1% of the volume. Component manufactured according to Claim 5 , 8th , 9 , 10th or 11 , characterized in that the coating remains at least partially on the component and the remaining coating enables or improves the function of the component, in particular by a hydrophilic or oleophilic or electrically conductive or electrically insulating property of the coating. Component manufactured according to one of the preceding method claims, characterized in that the component is a wear protection sleeve or a valve seat ring or a valve body or a valve housing part.

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