Method for manufacturing powder metallurgy components comprising drying with a gas stream before sintering

Abstract

The invention relates to a method for manufacturing a powder metallurgy component (21) comprising at least one longitudinally extending channel (22). A powder mixture comprising a metal powder (11) and a binder (12) is prepared and transferred to a processing device (31) comprising a mold (32). A green body (20) is subsequently formed via the mold. The green body (20) is dried by directing a gas flow (G) through the at least one longitudinally extending channel (22), and the dried green body (20) is sintered or oxidized to obtain the final component. The invention also relates to a drying tool (40) having a plurality of nozzles (44) for directing the gas flow into the longitudinal channels of the green body during drying.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a powder-metallurgical component having at least one longitudinally extending channel. In particular, the present invention relates to a method for drying a green body by directing a gas flow along the channel before sintering or oxidizing the green body. Background of the Invention

[0003] When using a wet binder to manufacture powder-metallurgical components, it has been found that slow drying due to water evaporation is not an option, as it is difficult to ensure that the green body retains the desired shape during drying. In particular, uneven drying of the green body can induce tension in the component, resulting in cracking or deformation of the component. This is particularly the case for asymmetric geometries, large components and thin-walled structures.

[0004] Therefore, a controlled acceleration or sometimes deceleration of in-depth drying is required. This is usually done by placing the green body to be dried in a space with a controlled temperature, such as in an oven. However, the use of heat only accelerates evaporation on the outer surface of the green body, i.e., results in uneven drying. In ceramic manufacturing, drying is usually done using microwaves, but this is not suitable for drying parts made of metal powders.

[0005] Therefore, improved methods for manufacturing powder metallurgy components would be advantageous.

[0006] Purpose of the Invention

[0007] It is therefore an object of the present invention to provide a method for producing a powder metallurgical component by means of which the risk of deformation and damage during the drying of the green body prior to sintering or oxidation can be minimized.

[0008] Another object of the present invention is to provide a method for manufacturing a powder metallurgy component, which facilitates the manufacture of more complex component geometries compared to known methods. This is related to the object of providing a method with a lower risk of damage caused by drying, since such damage may be caused by uneven drying of complex geometries, for example complex geometries due to large variations in the wall thickness of the component to be dried.

[0009] Yet another object of the present invention is to provide an alternative to the prior art.

[0010] In particular, an object of the present invention may be seen as providing a method for manufacturing a powder metallurgy component which solves the above-mentioned problems of the prior art. Summary of the invention

[0011] Therefore, the above-mentioned and several other objects are intended to be achieved by a first aspect of the present invention, which provides a method for manufacturing a powder metallurgy component, the component comprising at least one longitudinally extending channel, the method comprising the following steps:

[0012] - preparing a powder mixture comprising metal powder and a binder,

[0013] - transferring the powder mixture to a processing device comprising a mould,

[0014] - forming the powder mixture into a green body by forcing the powder mixture through a die, the die being suitable for forming the component into a shape having the at least one longitudinally extending channel,

[0015] - drying the green body by directing a gas flow through the at least one longitudinally extending channel, and

[0016] - Sintering or oxidizing the dried green body to bind the powders together to form the powder metallurgy component.

[0017] The at least one longitudinally extending channel may be closed along all of its side walls. It may also be open along one of the sides, in which case it may be necessary to close the open side to achieve the necessary guidance of the gas flow for providing drying.

[0018] The processing device may be, for example, an extruder, such as a piston extruder.

[0019] The powder mixture can be in the form of a paste. "Paste" refers to a thick, soft, viscous material made by mixing a liquid with a powder. In other words, a paste is usually composed of a suspension of a granular material in a background fluid. In the context of the present invention, the viscosity of the paste should allow the necessary treatment of the paste during the transfer of the paste from the device for mixing to the processing equipment. Subsequent processing steps should also be considered, that is, the viscosity of the paste should be low enough to allow forming, and should be high enough to ensure that the green body maintains the desired geometry. The viscosity of a given paste can be determined by the equipment and methods designed for this purpose, such as by using a capillary rheometer, which is generally used to measure shear viscosity (shear viscosity, shear viscosity) and other rheological properties. However, since viscosity is related to the hardness of the material, this parameter can also be used to determine whether a given paste is suitable for the manufacturing method. A related measurement method that can be used is the Shore Hardness (ShoreHardness) that can be determined according to ISO 868 / ASTM D2240. Another option is to use a special tool designed for clay; this has been used during the development of the present invention. This tool is similar to a Shore tester, but it has been adjusted to the characteristics of clay; such instruments may also be called clay durometers. Its operating principle is based on the force exerted by the sample material to penetrate the calibrated spring of the instrument when the pin of the tool is pressed into the material to be tested until the pin reaches the support. In this way, a stable force is always applied to the instrument during a stable stroke. It has a scale from 0 to 20 used as a relative hardness reference parameter, as well as a gram scale of the force applied. With this tool, the penetration point is pressed into the paste as the paste comes out of the kneader. Subsequently, the maximum value indicated by the moment when the penetration point is inside the paste is measured. The maximum point is used instead of waiting for it to stabilize, because it will eventually show a much lower value, which may be close to 0, because the penetration point will be forced through the paste. By this method, it has been found that values ​​above 12 Shore are required to obtain satisfactory results, at least for the geometries tested.

[0020] The metal may be any metal that can be used as a powder. A non-exhaustive list of possible metals includes: 316L (316L stainless steel), FeCrAl (iron chromium aluminum alloy), Inconel 625 (Inconel alloy 625), Hastalloy X (Hastelloy alloy X), 17-4PH (17-4PH stainless steel), 430L (430L stainless steel), and 304L (304L stainless steel).

[0021] Binder or binding agent is any material or substance that mechanically or chemically holds or attracts other materials together to form a cohesive unit by adhesion or cohesion. Binders are preferably organic, such as cellulose ethers, agarose or polyoxymethylene. Examples of binders are: methylcellulose, 25 polyethylene oxide, polyvinyl alcohol, sodium carboxymethylcellulose (cellulose gum), alginate, ethyl cellulose and asphalt.

[0022] The powder mixture may also include other ingredients, such as ceramic powders or lubricants. A non-exhaustive list of possible ceramics includes: AlO, SiO, ZiO, alumina, zirconia, boron nitride, cordierite, and silicon nitride.

[0023] The effect of the drying step described is that a more uniform drying of the entire part can be achieved. Research conducted as part of the development leading to the present invention has shown that such a drying step makes it easier to ensure that the part retains its intended shape without deforming or cracking. This is particularly desirable for complex geometries or small wall thicknesses, such as for parts with a large number of longitudinally extending internal channels, which may be separated by thin walls.

[0024] In some embodiments of the invention, the drying step further comprises directing a gas flow along an outer surface of the green body, so that drying also occurs from the outside due to the gas flow.

[0025] In an alternative embodiment, the drying step also includes, for example, covering the outer surface of the green body with a plate, so that the drying is performed only due to the gas flow passing through at least one longitudinally extending channel. Therefore, liquid can be prevented from evaporating from the outer surface. It has been found that at least for some geometric shapes of the manufactured parts, this provides more uniform drying. Whether the selection of covering the outer surface can be used to control the drying process, for example, in order to avoid undesirable deformation or cracking. It may, for example, depend on the geometric shape of the manufactured parts, including the thickness of the wall around the longitudinally extending channel. In addition to the influence on drying, the plate or other elements used to cover the outer surface can provide structural support for the green body during drying. Therefore, the support effect can be used to ensure that the green body maintains the desired shape during drying.

[0026] In some embodiments of the present invention, the following steps are performed before the drying step:

[0027] -Providing a drying tool, the drying tool comprising:

[0028] - a first end comprising or connectable to gas flow generating means, and

[0029] - an opposite second end comprising a plurality of nozzles, each nozzle being in fluid communication with the first end so that gas can flow through each of the nozzles under the action of the gas flow generating means during use of the drying tool,

[0030] - arranging the drying tool relative to the green body such that the nozzle of the drying tool extends into the end region of each of the at least one longitudinally extending channel of the green body,

[0031] - activating said gas flow generating means so that gas flows into each of said at least one longitudinally extending channel.

[0032] Examples of possible designs of such drying tools will be described in conjunction with the accompanying drawings.Such drying tools would be particularly advantageous for drying green bodies having multiple longitudinally extending channels, as such geometries would otherwise be more difficult to dry uniformly.

[0033] In an alternative embodiment of the invention in which the green body has a plurality of longitudinally extending channels, the method may include using a drying tool as described above, but the step of arranging the drying tool relative to the green body is performed in such a way that the nozzle of the drying tool extends into the end region of at least some (such as most) of the plurality of longitudinally extending channels of the green body.

[0034] "Majority" preferably means more than 50%, such as more than 70%, such as more than 90%.

[0035] By using the described drying tool and extending the nozzle into each or most of the plurality of longitudinally extending channels, uniform drying of the entire volume can be ensured. In addition, the shape and size of the nozzle can be designed so that the nozzle provides structural support for the part of the wall of the at least one longitudinally extending channel that comes into contact with the tool, thereby preventing its deformation. This has the advantage that the green body remains unchanged and the gas flow is not hindered as in a deformed (such as collapsed) longitudinally extending channel.

[0036] In some embodiments of the present invention, a plurality of nozzles of the drying tool are arranged over the entire cross section of the green body to be dried, thereby ensuring uniform drying of the entire component.

[0037] The nozzle may be shaped and sized such that it provides structural support to the portion of the wall of the at least one longitudinally extending channel that comes into contact with the tool, thereby preventing deformation thereof.

[0038] An alternative to using such a drying tool including a nozzle can be to use a drying tool with a connection end, which is used to guide the gas flow into at least one longitudinally extending channel. Such a drying tool should preferably have at least one seal or gasket, which is placed to engage with the open end of the green body or the at least one longitudinally extending channel, so that the gas is therefore guided into the channel. However, the scope of the claim covers any suitable method of guiding the gas through the at least one longitudinally extending channel. It can be provided by blasting or suction action. The flow generating device can be any type of device suitable for providing a gas flow. It can be, for example, a gas fan (gas fan, exhaust fan), a vacuum pump, a reverse fan (reverse fan) or a compressor. The gas flow generating device can be a component of the drying tool, or it can also be an external device connected to the drying tool.

[0039] An auxiliary tool may be arranged at an end of the green body opposite to the end where the drying tool is arranged, the auxiliary tool being adapted to support the at least one longitudinally extending channel during drying, thereby preventing undesired deformation of the green body.

[0040] "Support" preferably means that the auxiliary means supports part of the inner surface of the at least one channel and thereby prevents deformation thereof (such as collapse). The support should preferably be performed without significantly restricting the gas flow.

[0041] The length of the drying step may be a predetermined period of time, or may be determined by measuring the humidity of the gas that has flowed through the green body. It will depend on parameters including the material, geometry and size of the green body. Which measures to use may be determined experimentally, possibly with the aid of computer simulations.

[0042] In some embodiments of the present invention, a component is manufactured having a plurality of longitudinally extending internal channels, such as having a honeycomb structure.

[0043] The gas used for drying may have a higher or lower temperature than the surrounding air, and / or the gas may have a higher or lower humidity than the surrounding air. The gas may be, for example, air. Drying may also be controlled by varying the speed of the gas stream.

[0044] In any of the embodiments described above, a debinding step may be performed before the sintering or oxidation step, the debinding step typically comprising heating the green body to a temperature at which at least some (such as all) of the binder is burned off. This debinding step is typically performed after the drying step. Debinding refers to the process of removing the binder from the green body to ensure that there is no residual carbon in the part during sintering. This debinding is typically accomplished by heating the green body to a temperature between 200 degrees Celsius and 750 degrees Celsius and allowing the binder to burn off. Different binders require different debinding temperatures. In embodiments using methylcellulose, debinding is typically accomplished in an oxidizing atmosphere (typically air), but if the final part is not damaged by the additional carbon content, debinding can also be partially accomplished in the same atmosphere as the sintering atmosphere. In order to ensure that the debonded green body can still be handled, it may be necessary to slightly oxidize the powder together; these oxides will be removed during the sintering process.

[0045] A second aspect of the invention relates to a drying tool for drying a green body before sintering or oxidation during the manufacture of a powder metallurgy component, the drying tool comprising:

[0046] - a first end comprising or connectable to gas flow generating means, and

[0047] - an opposite second end comprising a plurality of nozzles, each nozzle being in fluid communication with the first end so that gas can flow through each of the nozzles under the action of the gas flow generating means during use of the drying tool, and

[0048] - said drying means are suitable for drying a part obtained by the method according to the first aspect of the invention.

[0049] In such a drying tool, a plurality of nozzles may be arranged in a predetermined pattern, such as in a regular pattern of aligned rows and columns. They may, for example, be arranged to match the pattern formed by the mutual positions of the longitudinally extending channels of the component manufactured by the method according to the first aspect of the invention as described above. In some embodiments, there are at least three rows of nozzles, each row comprising at least three nozzles.

[0050] The drying tool according to the invention may comprise a plurality of fluid channels, each extending between the first end and the nozzle. Thus, when the drying tool is used in the method according to the first aspect of the invention, it may help to achieve a uniform gas flow through all longitudinally extending channels. Thus, it may be easier to ensure uniform drying of the component, thereby avoiding or minimizing the risk of deformation and cracking due to drying.

[0051] At least some of the nozzles may comprise a closure mechanism for closing the respective nozzle so that no gas flows through the respective nozzle during use of the drying tool. The mutual position of at least some of the nozzles may be adjustable. By means of a drying tool having one or both of these two features, it is achieved that a given drying tool may be adapted to dry components having different geometries and sizes and comprising different numbers of longitudinally extending channels.

[0052] The first and second aspects of the present invention may be combined. These and other aspects of the present invention will become apparent from the embodiments described hereinafter and will be elucidated with reference to the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The method for manufacturing a powder metallurgy component according to the present invention will now be described in more detail with reference to the accompanying drawings. These drawings show one way of implementing the invention and should not be interpreted as limiting to other possible embodiments falling within the scope of the appended claims.

[0054] Figure 1 A method for producing a powder metallurgy component according to a first aspect of the invention is schematically shown. Figure 1 a shows the following steps: preparing a powder mixture; transferring it to a processing device; and forming a green body. Figure 1 b shows how the gas flow is directed through the internal channels of a green body having an outer surface covered by a plate. Figure 1 c shows sintering.

[0055] Figure 2 An example of a component having a plurality of longitudinally extending internal channels arranged in a regular pattern is schematically shown.

[0056] FIG. 3 schematically shows an embodiment of a drying tool according to a second aspect of the present invention. Figure 3a is a side view, Figure 3b is a three-dimensional partial view of the second end including the nozzle.

[0057] Figure 4 It is shown how the drying tool in FIG. 3 can be arranged such that the nozzles engage with the end sections of the channels of the green body during drying.

[0058] Figure 5 yes Figure 4 Cross-sectional view of the drying tool in FIG.

[0059] Figure 6 Figures 3 to 4 show schematically Figure 5 In the drying tool, some nozzles are closed by plugs.

[0060] Figure 7A drying tool is schematically shown in which the relative position of the nozzles can be adjusted.

[0061] Figure 8 The drying step is schematically shown, wherein auxiliary tools are used to support the green body.

[0062] FIG. 9 shows experimental results of tests performed during the development of the present invention. DETAILED DESCRIPTION

[0063] Figure 1 A method for manufacturing a powder metallurgy component according to a first embodiment of the present invention is schematically shown. Figure 1 As shown in a, a powder mixture is prepared by mixing at least a metal powder 11 and a binder 12. The powder mixture may include other ingredients, such as ceramic powder or a lubricant. The powder mixture is then transferred to a processing device 31 including a mold 32; it may be, for example, an extruder, such as a piston extruder. By forcing the powder mixture through the mold 32, the powder mixture is formed into a green body 20. This step is accomplished by applying a pressure P (as schematically indicated by the arrow in the accompanying drawing). The mold 32 is designed so that it is suitable for forming the component 21 into a shape having at least one longitudinally extending channel 22. In Figure 1 In the example, the part has only one channel, but parts with multiple channels can be produced by a similar method using another mold.

[0064] Figure 1 b schematically shows the step of drying the green body 20 by directing a gas flow G through the longitudinally extending channel 22. In the embodiment shown, the outer surface of the green body 20 is covered by a plate 39 so that drying occurs only due to the gas flow G passing through the longitudinally extending channel 22. The gas may have a higher or lower temperature than the surrounding air, and / or the gas may have a higher or lower humidity than the surrounding air. The gas is typically air, but other gases may also be used. Figure 1 b It can be seen that, in addition to ensuring that no water evaporation from the outer surface occurs, the cover sheet also provides structural support for the green body during drying.

[0065] The length of the drying step may be a predetermined time period determined, for example, by experiment. It may also be determined from measurements of the humidity of the gas that has flowed through the green body 20 during the drying process.

[0066] After drying, the final component 21 is obtained by sintering the dried green body, such as Figure 1c is schematically shown. This can be done, for example, in a reducing atmosphere, in a vacuum, or in an inert atmosphere. Sintering is typically performed in a furnace 34 at a temperature of 950 degrees Celsius to 1430 degrees Celsius. As explained in more detail above, a debinding step may occur before the sintering or oxidation step, the debinding step typically comprising heating the green body 20 to a temperature that burns off at least a portion (such as all) of the binder.

[0067] Figure 2 An example of a component 21 is shown schematically, which has a plurality of longitudinally extending internal channels 22 arranged in a regular pattern and separated by walls 23. If a properly designed mold 32 is used, such a component can be formed by combining Figure 1 The method is described for manufacturing.

[0068] FIG. 3 schematically shows an embodiment of a drying tool 40 for drying the green body 20 prior to sintering or oxidation. Figure 3a 4 is a side view showing a drying tool 40 having a first end 41 and an opposite second end 42, wherein the first end includes or can be connected to a gas flow generating device 43, and the second end includes a plurality of nozzles 44. The nozzles 44 are in fluid communication with the first end 41 so that gas can flow through each nozzle 44 under the action of the gas flow generating device 43 during use of the drying tool 40. Figure 3b 4 is a three-dimensional partial view of the second end 42 including nozzles 44. In the embodiment shown, the nozzles 44 are arranged in a regular pattern of aligned rows and columns. In the embodiment shown, the nozzles 44 have two different shapes, but the nozzles can be all the same, or there can be more nozzles of different shapes and sizes.

[0069] Figure 4 3 shows how the drying tool 40 can be arranged so that during drying the nozzle 44 engages with, such as extends into, an end section of the longitudinally extending channel 22 of the green body 20. By comparison Figure 2 3, it can be seen that the arrangement of the nozzle 44 of the drying tool 40 of FIG. 3 is similar to Figure 2 The arrangement of the internal channels 22 of the components in the drying tool 40 is matched. However, when this is not the case, the drying tool 40 can still be used, which will be shown below. It must be ensured that the nozzles 44 do not damage the green body 20. When the nozzles 44 have been arranged, the gas flow generation device 43 is actuated so that the gas flow enters each longitudinally extending channel 22. At the same time, the extension of the nozzles 44 into each internal channel 22 means that these nozzles provide uniform drying and support the wall 23. Both measures minimize possible deformation and damage to the green body 20.

[0070] Figure 5 yes Figure 44 is a cross-sectional view of a drying tool 40 in FIG. It shows that the drying tool 40 comprises a plurality of fluid channels 45, wherein each fluid channel extends between the first end 41 and the nozzle 44. Thus, a more uniform distribution of gas in all nozzles 44 can be achieved compared to embodiments in which the middle section of the drying tool 40 is an open space or has a smaller number of fluid channels 45. However, such embodiments will also be covered by this protection scope.

[0071] Some of the nozzles 44 may include a closure mechanism 46 for closing the corresponding nozzle 44 so that no gas flows through the corresponding nozzle during use of the tool. Examples of such embodiments are described in Figure 6 Schematically shown in FIG, wherein nozzles 44 located in the upper and lower rows of a drying tool 40 are shown as being closed using a closing mechanism 46, such as a removable plug. This may be appropriate, for example, if the drying tool 40 is used to dry a green body 20 having a smaller cross-section or a green body 20 having an outer region without an inner passage.

[0072] Figure 7 A drying tool 40 is schematically shown, wherein the nozzles 44 are in the form of flexible tubes, so that the mutual position of the nozzles 44 can be adjusted. Thus, the drying tool 40 can be used for green bodies 20 of different geometries. In some embodiments of the drying tool 40 with such adjustable nozzles 44, at least some of the nozzles 44 may include rigid end sections (not shown) adapted to support the walls 23 of the longitudinally extending channels 22 and thereby prevent them from deforming during drying as described above.

[0073] Figure 8 It is schematically shown how an auxiliary tool 47 can be arranged at the end of the green body 20 opposite to the end at which the drying tool 40 is arranged. The auxiliary tool 47 serves to support the longitudinally extending channel 22 during drying. Figure 8 In the drawing, this is schematically shown as small pins 48 protruding from the end surface of the auxiliary tool 47 so that these small pins 48 can extend into the longitudinally extending channels 22 of the green body 20 being dried.

[0074] Figure 9 shows the results of some tests carried out to investigate the effects of using a drying tool according to the invention. All six components are made of the same material and are extruded to have Figure 2 These experiments were repeated three times, Figure 9a , Figure 9b , Fig.9cThe lower part in the figure was left to dry without any forced air flow, and the upper part was dried by directing air through the internal channels using the drying tool according to the invention. The results clearly show how the use of the drying tool and the method according to the invention can be used to stabilize the part during drying and thereby prevent its undesired deformation.

[0075] Although the present invention has been described in conjunction with specific embodiments, it should not be interpreted in any way as being limited to the examples presented. The scope of the present invention is defined by the appended claim set. In the context of the claims, the terms "comprise" or "include" do not exclude other possible elements or steps. Furthermore, references to references such as "a" or "an" should not be interpreted as excluding the plural. The use of reference signs in the claims with respect to elements shown in the drawings should also not be interpreted as limiting the scope of the present invention. Furthermore, the various features mentioned in different claims may be advantageously combined, and the mention of these features in different claims does not exclude that a combination of features is impossible and disadvantageous.

Claims

1. A drying tool (40) for drying a green body (20) before sintering or oxidation during the manufacture of a powder metallurgy component (21), the drying tool (40) comprising: - a first end (41) comprising or connectable to gas flow generating means (43), and - an opposite second end (42) comprising a plurality of nozzles (44), each of said nozzles being in fluid communication with said first end (41) so that gas can flow through each of said nozzles (44) under the action of said gas flow generating means (43) during use of said drying tool (40), and in, - the drying tool (40) is suitable for drying the component (21), and The nozzle is shaped and sized such that it provides structural support to a portion of the wall of the at least one longitudinally extending channel that contacts the tool, thereby preventing deformation thereof.

2. The drying tool (40) according to claim 1, wherein: The plurality of nozzles (44) are arranged in a predetermined pattern.

3. The drying tool (40) according to claim 2, wherein: The plurality of nozzles (44) are arranged in a regular pattern of aligned rows and columns.

4. The drying tool (40) according to any one of claims 1 to 3, comprising a plurality of fluid channels (22), each of the fluid channels extending between the first end (41) and a nozzle (44).

5. The drying tool (40) according to any one of claims 1 to 3, wherein: At least some of the nozzles (44) include a closing mechanism (46) for closing the corresponding nozzle (44) so ​​that no gas flows through the corresponding nozzle during use of the drying tool (40).

6. The drying tool (40) according to any one of claims 1 to 3, wherein: The relative positions of at least some of the nozzles (44) are adjustable.

7. A method for manufacturing a powder metallurgy component (21) using a drying tool (40) according to any one of the preceding claims 1 to 6, the component (21) comprising at least one longitudinally extending channel (22), the method comprising the following steps: - preparing a powder mixture comprising a metal powder (11) and a binder (12), - transferring the powder mixture to a processing device (31) comprising a mold (32), - forming the powder mixture into a green body (20) by forcing the powder mixture through a die (32) suitable for forming the component (21) into a shape having the at least one longitudinally extending channel (22), - drying the green body (20) by directing a gas flow (G) through the at least one longitudinally extending channel (22), and - Sintering or oxidizing the dried green body (20) to bind the powder (11) together to form the powder metallurgy component (21).

8. The method according to claim 7, wherein: The drying step further comprises directing a gas flow (G) along the outer surface of the green body (20), so that the drying is also performed from the outside due to the gas flow (G).

9. The method according to claim 7, wherein: The drying step further comprises covering the outer surface of said green body (20) so that said drying occurs solely due to said gas flow (G) passing through said at least one longitudinally extending channel (22).

10. The method according to any one of claims 7 to 9, wherein: The following steps are performed before the drying step: - providing a drying tool (40), said drying tool comprising: - a first end (41) comprising or connectable to gas flow generating means (43), and - an opposite second end (42) comprising a plurality of nozzles (44), each of said nozzles being in fluid communication with said first end (41) so that gas can flow through each of said nozzles (44) under the action of said gas flow generating means (43) during use of said drying tool (40), - arranging the drying tool (40) relative to the green body (20) such that a nozzle (44) of the drying tool (40) extends into the end region of each of the at least one longitudinally extending channel (22) of the green body (20), and - activating the gas flow generating means (43) so that gas flows into each of the at least one longitudinally extending channel (22).

11. The method according to any one of claims 7 to 9, wherein: The green body has a plurality of longitudinally extending channels, and wherein the following steps are performed before the drying step: - providing a drying tool (40), said drying tool comprising: - a first end (41) comprising or connectable to gas flow generating means (43), and - an opposite second end (42) comprising a plurality of nozzles (44), each of said nozzles being in fluid communication with said first end (41) so that gas can flow through each of said nozzles (44) under the action of said gas flow generating means (43) during use of said drying tool (40), - arranging the drying tool (40) relative to the green body (20) such that the nozzle (44) of the drying tool (40) extends into the end region of most of the plurality of longitudinally extending channels (22) of the green body (20), and - activating the gas flow generating means (43) so that gas flows into the majority of the plurality of longitudinally extending channels (22).

12. The method according to claim 10, wherein: The plurality of nozzles of the drying tool (40) are arranged over the entire cross section of the green body (20) to be dried.

13. The method according to claim 10, wherein: The nozzle is shaped and sized such that it provides structural support to a portion of the wall of the at least one longitudinally extending channel that contacts the tool, thereby preventing deformation thereof.

14. The method according to claim 10, wherein: An auxiliary tool (47) is arranged at the end of the green body (20) opposite to the end where the drying tool (40) is arranged, the auxiliary tool (47) being suitable for supporting the at least one longitudinally extending channel (22) during drying.

15. The method according to any one of claims 7 to 9, wherein: The length of the drying step is a predetermined period of time.

16. The method according to any one of claims 7 to 9, wherein: The length of the drying step is determined by measuring the humidity of the gas that has flowed through the green body (20).

17. The method according to any one of claims 7 to 9, wherein: The produced component (21) has a plurality of longitudinally extending internal passages (22).

18. The method according to claim 17, wherein: The manufactured component (21) has a honeycomb structure.

19. The method according to any one of claims 7 to 9, wherein: The gas has a higher or lower temperature than the surrounding air, and / or wherein the gas has a higher or lower humidity than the surrounding air.

20. The method according to any one of claims 7 to 9, wherein: A debinding step is performed prior to the sintering or oxidation step.

21. The method according to claim 20, wherein: The debinding step includes heating the green body (20) to a temperature that burns off at least some of the binder (12).

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