Cathode part, anode part, supply unit, device for thermal spraying, method for producing a cathode part and / or anode part of this type, method for operating a device for thermal spraying, use of a cathode part, use of an anode part and use of a supply device for powder particles
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-06-16
- Publication Date
- 2026-03-19
AI Technical Summary
Existing thermal spraying devices face inefficiencies in powder particle utilization, energy consumption, and cathode part overheating, leading to reduced performance and increased emissions.
A cathode part with a powder channel and additional cooling channel, designed using additive manufacturing, allows for preheating and efficient powder delivery, while an anode part with integrated channels facilitates compact and efficient plasma generation.
Enhances powder particle utilization, reduces energy consumption, and prevents overheating, resulting in a more efficient and compact thermal spraying process with improved particle delivery and plasma generation.
Smart Images

Figure EP2025066705_19032026_PF_FP_ABST
Abstract
Description
[0001] Cathode part, anode part, feeding device, thermal spraying device, method for manufacturing such a cathode part and / or anode part, method for operating a thermal spraying device, use of a cathode part, use of an anode part and use of a powder particle feeding device
[0002] The invention relates on the one hand to a cathode part for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying.
[0003] The invention relates, on the other hand, to an anode part for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying.
[0004] The invention further relates to a feeding device for supplying powder particles to a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying.
[0005] The invention further relates to a device for thermal spraying of metallic and / or ceramic spray material, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a central axis, with a housing, with a plasma chamber for plasma, with a cathode part for generating an arc, with an anode part for generating an arc, and with a device for introducing powder particles.
[0006] The invention further includes a use of a cathode part.
[0007] The invention also relates to a use of an anode part.
[0008] The invention also relates to the use of a feeding device for powder particles.
[0009] Cathode parts and anode parts of a type for thermal spraying, as well as such a device, are already known from the prior art.
[0010] The invention is based on the objective of providing an improvement or an alternative to the prior art.
[0011] According to a first aspect, the invention solves the problem of a cathode section for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, comprising a base body having a longitudinal axis and a powder channel extending along the longitudinal axis for guiding powder particles from an input side of the cathode section to an output side of the cathode section through the cathode section. Advantageously, the cathode section can have at least one further channel for guiding another medium through the cathode section. Furthermore, it is advantageous that the at least one further channel can be arranged at least partially around the powder channel.
[0012] Because the cathode part has a powder channel, it can be used not only for generating an electric arc, but also for supplying powder particles to the thermal spraying device.
[0013] Advantageously, the powder particles can be preheated as they flow through the cathode section, so that the preheated powder particles can be melted even more efficiently by a plasma located further downstream and / or by a medium heated by the plasma.
[0014] This allows such a device to be built much more compactly and also to be operated more energy-efficiently and / or with lower emissions. Furthermore, a higher utilization rate of powder particles can be achieved. In other words, the amount of powder applied to a substrate can be increased.
[0015] To prevent the cathode part from overheating and wearing out disproportionately during its use in a thermal spraying device, it may be advantageous if the cathode part has an additional channel through which another medium can flow, for example a liquid coolant.
[0016] The additional cooling of the cathode section achieved with this feature allows for thermally stable operation, thus preventing melting during use. However, it should be explicitly noted that a cathode section can also be designed without an additional channel.
[0017] Furthermore, targeted temperature management of the powder particles can be achieved, for example, to avoid the risk of powder particles melting and clumping at the powder channel. The term "longitudinal axis" here preferably describes the central axis extending longitudinally along the base body.
[0018] Along the longitudinal axis or in its direction, the powder particles are also conveyed through the base body of the cathode part.
[0019] The longitudinal axis can also be considered a main axis of rotation of the base body.
[0020] Preferably, the base body or the cathode part is entirely rotationally symmetrical around the longitudinal axis.
[0021] The base body is preferably elongated, preferably cylindrical, whereby the base body can alternatively also have oval, rectangular or similar cross-sectional shapes if this appears advantageous for a particular application.
[0022] Advantageously, the powder channel is designed to be long enough along the longitudinal axis to provide an advantageous acceleration section, especially when using a Laval nozzle area, for the powder particles at the cathode part.
[0023] The powder particles can be introduced axially into a plasma or plasma chamber of the device for thermal spraying via the powder channel, in particular axially along the longitudinal axis of the cathode part.
[0024] To implement the powder channel described here, it is advantageous if the powder channel has an entry opening on the entry side and an exit opening on the exit side.
[0025] In the context of the invention, the term "feed side" describes the side of the base body where, in particular, the powder particles are fed into the cathode section. The feed side specifically includes the front, feed-side end face, and extending from there, an area of approximately one-third of the total length of the cathode section can also be considered part of this feed side, viewed along the longitudinal axis in the direction of powder particle conveyance.
[0026] Accordingly, the term "discharge side" within the meaning of the invention describes the side of the base body from which, in particular, the powder particles are discharged from the cathode section. The discharge side thus comprises the rear, discharge-side end face of the cathode section. Starting from the rear end face, this discharge side can also include an area of approximately one-third of the total length of the cathode section, measured in the opposite conveying direction along the longitudinal axis.
[0027] Since such devices for thermal spraying and their components are already known from the prior art, neither their structural design nor their operating principles will be described in detail here.
[0028] In any case, the present device for thermal spraying relates to the thermal coating of a substrate, i.e., a body to be coated, by means of a spray material. This spray material is supplied to the device in the present case as a powder in the form of powder particles, wherein the powder is melted directly and / or indirectly in the device by means of plasma, then ejected from the device and accelerated in the direction of the substrate.
[0029] Advantageously, the cathode section can be designed as an annular cathode section, i.e., as a ring-shaped cathode extending around a powder channel. Advantageously, the powder channel can be configured to guide a focusing gas. According to a second aspect of the invention, the object is solved by a cathode section for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a base body having a longitudinal axis and at least one channel for guiding a medium through the cathode section, wherein the cathode section is generated at least partially, and in particular completely, by an additive manufacturing process.
[0030] The additive manufacturing process makes it possible to produce the present cathode part with at least one channel, in particular with the powder channel and also with further channels, in a particularly simple and compact manner.
[0031] Additive manufacturing enables the production of comparatively complex geometries that cannot be produced using subtractive manufacturing processes, or only with significantly greater effort. The manufacturing quality achieved with additive manufacturing is particularly independent of geometric complexity, meaning that even complex geometries can be produced with relatively high precision.
[0032] A particular advantage here is that such a cathode component can be manufactured with extreme precision even with the smallest dimensions, especially with extremely delicate channels and channel walls or the like.
[0033] Even intricately angled or multiply curved channels inside the base body can be easily implemented in the cathode section using this method. Furthermore, channels with advantageous internal structures can be created, which can, for example, improve the conveyance of powder particles, cooling media, or the like within the cathode section.
[0034] Furthermore, such a cathode component can be advantageously manufactured even if it is designed cumulatively or alternatively from different materials.
[0035] The term "additive manufacturing process" is also frequently referred to as generative manufacturing process, whereby additive or generative manufacturing processes, in contrast to classic subtractive manufacturing processes such as milling, drilling, turning, EDM or the like, are characterized in particular by the fact that materials can be added or "added" essentially layer by layer in order to manufacture components, such as the present cathode part, in a more compact form.
[0036] Such additive manufacturing processes can preferably eliminate entirely manufacturing processes that are based on joining methods such as welding, soldering, or the like. In particular, different functional areas on the cathode part, especially its geometric configurations, can be produced or formed very easily or even exclusively using an additive manufacturing process, especially functional areas inside the cathode part.
[0037] Various additive manufacturing processes can be used in accordance with the invention, such as 3D printing, 3D laser sintering, or the like. In particular, selective laser melting (SLM) processes are also suitable for use in accordance with the invention. It is advantageous if shapeless or shape-neutral materials are used for manufacturing. Shapeless materials, as defined in the invention, include, for example, liquids, powders, or similar substances, while shape-neutral materials can be in the form of ribbons, wires, or the like.
[0038] Regarding the aforementioned 3D printing process, a distinction can be made between powder bed fusion, free-space fusion and liquid material fusion processes.
[0039] Powder bed processes include selective laser melting (SLM), selective laser sintering (SLS), selective heat sintering (SHS), binder jetting (solidification of powder material using a binder) and electron beam melting (EBM).
[0040] Free-space processes include fused depositing modeling (FDM) or fused filament fabrication (FFF), laminated object modeling (LOM), cladding, wax deposition modeling (WDM), contour crafting, cold injection molding, and electron beam welding (EBW).
[0041] Examples of liquid material processes include stereolithography (SLA) and micro-SLA, digital light processing (DLP) and liquid composite moulding (LCM).
[0042] A more compact design, as described in the invention, can be achieved particularly easily if the manufacturing process involves operating a single production line for a component that is, in particular, monolithic. Preferably, only a single data set is required for manufacturing, containing all the information necessary for producing, in particular, the cathode section. In this way, the production of the cathode section can be largely automated, thus enabling production with reduced labor costs. Advantageously, the cathode section can be designed as a ring cathode section, i.e., as a ring-shaped cathode extending around a channel, in particular a powder channel. Advantageously, one of the channels can be configured to guide a focusing gas.
[0043] The cathode part can be used particularly advantageously in the present case as a feeding device for supplying media into a plasma chamber of the device for thermal spraying, if at least one channel of the cathode part, in particular a powder channel, has a longitudinal extension which is many times longer in the direction of the longitudinal axis than a transverse extension of the at least one channel transverse to the longitudinal axis.
[0044] By means of such an advantageously designed longitudinal extension, the injection of powder particles into a plasma chamber of the thermal spraying device, or into a plasma bubble generated therein, can be carried out even more precisely and efficiently. In particular, the efficiency of the thermal spraying device can be improved as a result. Furthermore, the flow of the powder particles through the plasma bubble can be controlled more precisely, thereby improving the homogeneous heating of the powder particles.
[0045] Since the cathode section is thermally stressed by generating an electric arc, powder particles can be effectively preheated immediately as they pass through the powder channel. This allows a separate powder preheating device upstream of a feeder to be operated with less energy consumption, if required, or even eliminates the need for such an additional powder preheating device altogether, or at least allows it to be designed smaller. While the longitudinal extent describes the clear length of the channel or powder channel, the transverse extent consequently describes the clear diameter of the channel or powder channel.
[0046] The term “by a multiple” describes, within the meaning of the invention, a diameter / length ratio of 1 / 10 or more, preferably 1 / 20 or more and particularly preferably 1 / 50 or more, and / or a diameter / length ratio of 1 / 150 or less, preferably 1 / 100 or less and particularly preferably 1 / 80 or less.
[0047] The shorter the powder channel, the more compact the electrode part.
[0048] A longer powder channel allows for more targeted discharge of the powder from the cathode section and its introduction into the plasma. This, in particular, enables higher injection speeds, allowing the powder particles to be fed into the plasma.
[0049] It is particularly advantageous if the powder channel of the cathode part and the base body are generated together using an additive manufacturing process.
[0050] The additive manufacturing process used here allows the cathode part to be manufactured particularly easily and cost-effectively as a wear part.
[0051] Furthermore, it can be advantageous if at least one channel of the cathode section, in particular a powder channel, has an acceleration section for accelerating powder particles, especially a powder particle-carrier gas mixture. It has been shown that it is structurally advantageous if a corresponding acceleration section is provided directly by means of the cathode section for accelerating and advantageously guiding the powder particles. This eliminates the need for an additional external feeding device for supplying powder particles, comprising, for example, a tubular element or the like.
[0052] The acceleration section can be longer than the base body extending between the input-side end face of the cathode part and the output-side end face of the cathode part if the powder channel of the cathode part has a tube section that projects beyond the base body on the input side.
[0053] Advantageously, the pipe section and the base body are generated together using an additive manufacturing process.
[0054] Furthermore, it is advantageous if the cathode part has a ring element on its discharge side, which is particularly securely arranged on the base body.
[0055] The discharge side can be designed to be particularly advantageous for interaction with an electric arc if the ring element is designed as a ring cathode part.
[0056] To be particularly well-suited to the requirements of interacting with an electric arc, and / or to exhibit advantageous electrical conductivity, and / or to enable lower overall costs for the cathode section, it is further advantageous if the base body of the cathode section and the ring element of the cathode section are made of different materials. For example, this additional ring element is designed with regard to its material properties to interact with an electric arc, which is advantageous for generating plasma.
[0057] While the base body of the cathode part is advantageously made of copper or an alloy thereof, for example to have good thermal conductivity and / or electrical conductivity, the ring element can be made of a different material, in particular a material with good wear properties.
[0058] According to a preferred embodiment, the ring element can be manufactured and / or applied using an additive manufacturing process.
[0059] In particular, the stability of the cathode part can be advantageously increased if the ring element is made of wool frame or a wool frame alloy.
[0060] For example, the wofram alloy may include wofram lanthanum oxide, wofram cerium oxide, wofram thorium oxide, or the like.
[0061] Depending on the application, the ring element can be of varying thickness.
[0062] Dimensions for the ring element have proven particularly suitable when the ring element has a wall thickness of 0.5 mm or more, preferably 1.5 mm or more, and especially preferably 3 mm or more. Such wall thicknesses are particularly suitable for lower power ranges of the cathode section.
[0063] For higher-performance cathode components, however, larger wall thicknesses appear more suitable. In order to keep the material costs of the cathode component low, it is advantageous if the ring element has a wall thickness of 5 mm or less, preferably 4 mm or less, and particularly preferably 3.5 mm or less.
[0064] The term "wall thickness" here describes the thickness of the ring element orthogonal to the flat side of the ring element, i.e. in the direction of the longitudinal axis of the cathode part.
[0065] The present cathode part can be realized particularly advantageously if the ring part and the base body are generated together using an additive manufacturing process.
[0066] For particularly good heat management at the cathode section, it is advantageous if the cathode section has a cooling channel with a supply and a return, each of which has a connection for connecting to a primary cooling device, each of which is arranged in an area of the cathode section facing the input side.
[0067] The connections of the cooling channel are very easily accessible on the cathode part in the area of the entry side.
[0068] The connections can be located on the end face at the entry side. Preferably, the connections are arranged on the outer surface of the base body, so that the installation space on the entry-side end face of the cathode part is preferably available solely for the powder channel and a corresponding sealing periphery.
[0069] Advantageously, the cooling channel is designed for a flow rate of cooling medium of approximately at least 5 1 / min and up to approximately 60 1 / min at pressures between 1 bar and approximately 20 bar, so that a sufficiently large cooling capacity can be covered at the cathode part for most required power ranges.
[0070] Therefore, it is advantageous if the cooling channel has a cross-sectional area of 2 mm². 2 or more, preferably 4 mm 2 or more and especially preferably of 10 mm 2 or more.
[0071] Furthermore, the cooling channel advantageously has a cross-sectional area of 25 mm². 2 or more, preferably 50 mm 2 or more and especially preferably of 75 mm 2 or more.
[0072] A smaller cross-section or a smaller cross-sectional area of the cooling channel is particularly suitable for lower-performance cathode components, which therefore also require lower cooling capacities.
[0073] Larger cross-sections, on the other hand, are preferentially suited for more robust cathode sections. As a first approximation, it can be assumed that the required cooling capacity of a plasma torch is about one-third of the total power of the plasma torch, so that the above values for the cross-sectional area of the cooling channel can enable temperature-stable operation of a plasma torch.
[0074] In order to equip even extremely powerful thermal spraying devices with the cathode part according to the invention, it is sufficient if the cross-sectional area has a maximum size of 100 mm². 2 exhibits .
[0075] Therefore, a cross-sectional area of 75 mm² is usually sufficient for the cooling channel. 2 or less, preferably 50 mm 2 or less and especially preferably of 25 mm 2 or less. In order to ensure sufficient stability of the cathode section, for example with regard to high pressures, temperatures, temperature fluctuations, etc., it is advantageous if a wall is arranged between the flow and the return, which has a wall thickness of 0.3 mm or more, preferably 0.8 mm or more, and particularly preferably 1.2 mm or more.
[0076] For example, good heat transfer from the cathode part to a cooling medium circulating in the cooling channel can be achieved if a wall is arranged between the flow and the return, which has a wall thickness of 5 mm or less, preferably 4 mm or less and particularly preferably 3 mm or less.
[0077] Particularly advantageous in terms of the ratio of good stability and heat conduction through the wall can be achieved on the cathode part if the wall thickness is in a range greater than or equal to 2 mm and less than or equal to 3 mm.
[0078] Furthermore, it is advantageous if the cathode part has another channel for guiding another medium from the input side to the output side through the cathode part, wherein the second, other channel is preferably arranged concentrically around the powder channel.
[0079] The other channel can, for example, be used to guide a bundle medium through the cathode section and supply it at the discharge side. This reduces the risk of critical divergence of powder particles exiting at the discharge side, ensuring that these powder particles are fed to the plasma and / or plasma chamber in the most compact form possible. While the cooling channel provides primary cooling to the cathode section, the other channel can also be used for secondary cooling of the cathode section while the bundle medium is being guided through it.
[0080] The bundle medium is preferably an inert gas, such as argon, nitrogen or similar, in order to avoid undesirable reactions with the melted powder particles or, in particular, with the plasma as much as possible.
[0081] In order for the bundled gas to be able to leave the cathode section in the immediate vicinity of the powder channel discharge opening and not be directed back towards the input side, as is the case with the cooling medium with respect to the cooling channel, it is advantageous if the other channel on the discharge side of the cathode section has an outlet opening for the medium to exit the cathode section.
[0082] The outlet opening of the other channel can be designed differently. Preferably, the outlet opening is designed as an annular nozzle, which is arranged concentrically around the discharge opening of the powder channel.
[0083] The outlet opening can extend particularly close to the powder channel if the outlet opening is arranged radially further inside a ring element which is located on the discharge side of the cathode part.
[0084] If a cooling channel of the cathode section and / or another channel of the cathode section each has at least one additional guiding element for directing the respective medium, the media can be guided more precisely through the respective channel. For example, the respective medium can be guided particularly evenly through the respective channel by means of the additional guiding element.
[0085] For example, the flow of a medium through a channel can be slowed down by means of the additional guiding element, for example to keep a cooling medium in contact with the wall of the cathode part for a longer period of time.
[0086] If necessary, powder particles guided through the powder channel can be bundled more precisely to enable a further improved feed to the plasma and / or the plasma chamber.
[0087] If the at least one additional guiding element has a wall thickness of 0.1 mm or more, preferably 1 mm or more and particularly preferably 2 mm or more, it can be designed to be sufficiently stable to withstand higher operating pressures or the like.
[0088] If the at least one additional guiding element has a wall thickness of 5 mm or less, preferably 4 mm or less and particularly preferably 3 mm or less, it occupies as little space as possible within the respective channel, so that as much cross-sectional area as possible can be obtained for conveying a medium in the respective channel, thereby optimizing the associated pressure losses.
[0089] If necessary, several such guide elements can be arranged one behind the other in a channel.
[0090] Very good effects on the channel can be achieved with the guiding element if it has a length of approximately 10 mm. To achieve sufficiently good effects, it is advantageous if the at least one additional guiding element has a length of 2 mm or more along the longitudinal axis of the base body, preferably 4 mm or more, and particularly preferably 6 mm or more.
[0091] It is also advantageous if the at least one additional guide element along the longitudinal axis of the base body has a length of 20 mm or less, preferably 16 mm or less and particularly preferably 12 mm or less.
[0092] With such a length, even several guide elements can still be arranged one behind the other in a channel, including guide elements of different designs, in order to achieve different effects in a single channel if necessary.
[0093] The guiding elements can be implemented in a wide variety of geometries.
[0094] It has been shown that the respective medium can be guided particularly advantageously through the corresponding channel if the at least one additional guiding element for imparting a swirling motion to the respective medium comprises a guide vane part or several guide vane parts.
[0095] The respective medium can, for example, be subjected to a swirling motion particularly easily if at least one additional guiding element has a helical structure.
[0096] The at least one additional guide element can be advantageously designed if the helical structure has a pitch of 1 mm or more along the longitudinal axis of the cathode portion, preferably 5 mm or more, and particularly preferably 15 mm. Here, "pitch" is defined analogously to a thread pitch as a longitudinal extent per helix revolution. In other words, a pitch of 20 mm means that a helical cooling channel completes exactly one turn along a longitudinal extent of 20 mm in the longitudinal direction of the cathode portion.
[0097] In order to ensure that the effects caused by the helical structure do not have a counterproductive effect on the respective medium, it is advantageous if the helical structure has a slope of 50 mm or less along the longitudinal axis of the cathode part, preferably 40 mm or less and particularly preferably 30 mm or less.
[0098] A slope of 20 mm is particularly advantageous.
[0099] The at least one additional guiding element can have an additional stabilizing effect on the cathode part if the at least one additional guiding element includes a support structure of the cathode part.
[0100] Such a supporting structure can be constructed in different ways, for example as ribs or the like.
[0101] The at least one additional guide element can be loosely inserted into the cooling channel and / or into the further channel, in particular inserted thereafter.
[0102] If, however, the at least one additional guide element is generated together with the cathode part by means of an additive manufacturing process, the at least one additional guide element and the cathode element can be manufactured together particularly advantageously and, in accordance with the invention, also monolithically. In particular, the at least one additional guide element can support or stabilize the cathode part on the channel particularly well.
[0103] Furthermore, it is advantageous if the cathode part has an outer diameter of 5 mm or more, preferably 10 mm or more and particularly preferably 15 mm or more.
[0104] By using such outer diameters, the cathode part can be provided with sufficient mass to easily and reliably accommodate at least one channel, and preferably two or more channels, in the base body without critically weakening the structural integrity of the base body or the cathode part.
[0105] The cathode part can be provided in a sufficiently compact form if the cathode part has an outer diameter of 30 mm or less, preferably 25 mm or less and particularly preferably 20 mm or less.
[0106] If the cathode part has at least one seat on its outer surface for a mounting element to hold the cathode part securely on a housing of the thermal spraying device, the cathode part can be arranged on the device particularly easily.
[0107] In this context in particular, the cathode part can be generated very easily if the seat is generated using an additive manufacturing process.
[0108] Overall, the cathode part can be advantageously manufactured if the cathode part, in particular the base body thereof, and / or at least one channel thereof, in particular the powder channel, the fluid channel, and / or the ring element thereof, are formed monolithically, in particular as a single monolithic block.
[0109] According to a third aspect, the object of the invention is to provide an anode part for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a base body having a longitudinal axis, with a main channel extending along the longitudinal axis and with at least one further channel for guiding a further medium through the anode part, wherein the at least one further channel is arranged at least partially around the main channel, and wherein the main channel of the base body alone provides, in particular completely provides, a receiving area for at least partially receiving a cathode part within the anode part and a plasma chamber area for generating plasma within the anode part.
[0110] Optionally, the main channel of the base body forms a Laval nozzle-like area for accelerating powder particle-loaded plasma within the anode section and subsequently venting powder particle-loaded plasma.
[0111] A "Laval nozzle-like region" is understood to be a region that is designed in a manner comparable to a Laval nozzle, whereby a Laval nozzle-like region may be functionally adapted to gas-dynamic characteristics of the plasma gas.
[0112] Because the main channel of the anode section houses the receiving area for the cathode section, the plasma chamber for the plasma, and the Laval nozzle-like area for the accelerated ejection of powder-particle-laden plasma from the anode section, the anode section is extremely compact despite this number of different functional areas. This allows the powder particles introduced into the main channel to pass directly from the receiving area into the plasma chamber and then into the Laval nozzle-like area, enabling the powder particles to be melted particularly efficiently within the plasma and ejected directly into the environment as a plasma-powder particle mixture from the anode section.
[0113] This is achieved in particular by the fact that all areas, i.e. the recording area, the plasma chamber area and the Laval nozzle-like area, are directly adjacent to each other and thus each merge directly into the other.
[0114] More precisely, the recording area and the plasma chamber area share a common interface or transition area.
[0115] Furthermore, the plasma chamber area and the Laval nozzle-like area share a common, further interface or a common, further transition area.
[0116] Here, the interface or transition area of the intake area and the plasma chamber area is located in front of the further interface of the plasma chamber area and the Laval nozzle-like area, viewed in the direction of flow along the longitudinal axis.
[0117] The interface and the further interface, or the transition region and the further transition region, are separated and spaced apart solely by the plasma chamber region.
[0118] The interface and the further interface are preferably arranged parallel to each other, allowing for a geometrically simple design of the anode section. Preferably, the interface and the further interface are of the same size or differ only negligibly in their base areas, enabling a cylindrical design of the plasma chamber region.
[0119] In this case, the receiving area has a receiving chamber for at least partially receiving a part of the cathode.
[0120] The plasma chamber area features a plasma chamber in which a plasma is not only generated or ignited, but also enclosed to a limited extent, in particular as a plasma bubble.
[0121] It is particularly advantageous if the plasma chamber area is designed as a mixing chamber for mixing powder particles and plasma, so that the passage of the plasma by the powder particles can be achieved and / or ensured.
[0122] The Laval nozzle-like area features a Laval nozzle, by means of which plasma loaded with powder particles can be jetted out of the anode section and applied directly to a substrate.
[0123] In the present case, the receiving area, the plasma chamber area and the Laval nozzle-like area all have a common central axis, which is preferably the central longitudinal axis of the anode part.
[0124] Preferably, the receiving area, the plasma chamber area and the Laval nozzle-like area are designed to be rotationally symmetrical with respect to this longitudinal axis of the anode part.
[0125] Advantageously, a cathode part can be arranged centrally directly in front of the plasma chamber of the anode part, so that powder particles, which are discharged by a correspondingly constructed cathode part, in particular by the cathode part described here, can be introduced directly into the plasma chamber and in particular into the plasma, preferably centrally there.
[0126] The main channel extends from a receiving side of the anode part to a nozzle side of the anode part.
[0127] In the context of the invention, the term "receiving side" describes the side of the base body on which, in particular, a cathode part is inserted and placed into the anode part.
[0128] The receiving side includes in particular the front end face of the anode part and from there an area of about one third of the total length of the anode part can also be attributed to this receiving side, viewed in the direction of conveyance of the powder particles along the longitudinal axis.
[0129] Accordingly, the term "nozzle side" within the meaning of the invention describes that side of the anode body from which, in particular, the plasma enriched with powder particles is jetted out of the anode part. The nozzle side thus comprises the rear end face of the anode part. Starting from the rear end face, this nozzle side can also include an area of approximately one-third of the total length of the anode part, measured in the opposite direction of flow along the longitudinal axis.
[0130] In any case, the proposed anode section allows different functional areas of a thermal spraying device to be arranged compactly in the smallest possible space, such as, in particular, a receiving chamber for receiving a cathode section in the anode section, a plasma chamber for igniting and maintaining plasma in the anode section, and a Laval nozzle for optimal acceleration and optimally accelerated ejection of plasma loaded with powder particles.
[0131] According to a fourth aspect, the invention solves an anode part for a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, comprising a base body having a longitudinal axis, a receiving side having a receiving area for at least partially receiving a cathode part, a nozzle side having a nozzle area for dispensing plasma, in particular plasma loaded with powder particles, a channel-like plasma chamber area for generating plasma, which is arranged between the receiving side and the nozzle side, and at least one channel for guiding at least one medium through the cathode part, wherein the anode part is at least partially generated by means of an additive manufacturing process, in particular is generated completely by means of an additive manufacturing process.
[0132] The additive manufacturing process makes it possible to produce the present anode part with its different functional areas and at least one channel in a particularly simple and compact way.
[0133] A particular advantage here is that such an anode component can be manufactured with extreme precision even with the smallest dimensions, especially with extremely delicate channels and channel walls or the like.
[0134] Even intricately angled or multiply curved channels can be easily implemented on the anode section using this method. Furthermore, channels with advantageous internal structures can be created.
[0135] Furthermore, such an anode component can be advantageously manufactured even if it is made cumulatively or alternatively from different materials.
[0136] The channel-like plasma chamber area can be regarded as a branch of the anode part associated with a cathode, especially if the anode part is designed in such a way that it can be used in an active connection with several cathodes simultaneously, particularly in active connection with a three-cathode plasma burner.
[0137] In other words, an anode section is also proposed here, which can be designed to be used in conjunction with multiple cathodes. In particular, an anode section of a three-cathode plasma burner can be considered, which can have several, especially three, channel-like plasma chamber regions.
[0138] The anode section can be designed even more simply and built more compactly if the receiving area is set up to receive exactly one single cathode section, in particular an axial triple-cathode burner section.
[0139] Advantageously, this single cathode section can be positioned precisely centrally in front of the plasma chamber by the proposed design of the anode section, so that powder particles guided through the cathode section can be introduced preferably centrally into the plasma chamber, and in particular into the plasma ignited in the plasma chamber, as soon as the powder particles exit the cathode section. If the anode section has an inlet opening for introducing plasma gas to generate plasma, and the receiving area includes this inlet opening, the anode section can still be designed very simply despite the functional extension.
[0140] The entry opening can be designed as the main opening on the inlet side of the anode section.
[0141] Alternatively, the functionality of the anode part can be advantageously extended cumulatively, preferably with the same design, if the anode part has an inlet opening for introducing powder particles to generate powder particle-loaded plasma, wherein the receiving area of the anode part includes this inlet opening.
[0142] The entry opening can be designed as the main opening on the inlet side of the anode section.
[0143] Therefore, the insertion opening and the entry opening can both be designed by means of this one main opening, with the receiving area encompassing this main opening.
[0144] Furthermore, it is advantageous if the insertion opening and / or the injection opening are arranged in front of the plasma chamber area of the anode part.
[0145] This allows both plasma media for generating plasma and particle powder to be introduced upstream of the plasma chamber into the anode section, so that they can then preferably enter the plasma chamber together.
[0146] It is advantageous if the intake area extends in a funnel shape and / or tangently to the plasma chamber area. This allows not only the entry and injection openings to extend advantageously to the plasma chamber, thus facilitating the supply of the relevant media to the plasma chamber, but also enables a cathode section to be positioned centrally directly in front of the plasma chamber.
[0147] Furthermore, it can be advantageous if the receiving area is designed such that the plasma gas develops a rotational component in interaction with the receiving area, in particular a rotational component about an axis extending substantially in one flow direction of the plasma gas, and / or the plasma gas already flows into the receiving area with a rotational component. This can be particularly advantageous for certain material compositions of the plasma gas.
[0148] According to a first advantageous embodiment, the inlet opening and / or the feed opening is arranged axially in front of the plasma chamber area of the anode section. This can be a particularly advantageous design, especially for three-cathode plasma burners.
[0149] According to a second variant, the injection opening and / or the injection opening is arranged in front of the plasma chamber area of the anode part in such a way that injection from the cathode can occur radially with respect to the longitudinal axis of the base body of the anode part and / or injection from the cathode with respect to the longitudinal axis of the base body of the anode part can have a radial component.
[0150] According to a third variant, the injection opening and / or the entry opening is arranged in the anode part and in front of the plasma chamber area of the anode part, wherein injection from the cathode can take place radially with respect to the longitudinal axis of the base body of the anode part and / or injection from the cathode with respect to the longitudinal axis of the base body of the anode part can have a radial component.
[0151] According to a fourth variant, the insertion opening and / or the entry opening is arranged behind the anode part.
[0152] This can be implemented particularly well if the insertion opening and the entry opening are identical.
[0153] If the insertion opening and the entry opening are identical, the anode part can be manufactured even more easily.
[0154] Furthermore, it is advantageous if the recording area is cylindrical on one section facing the recording side and conical on another section facing the plasma chamber area.
[0155] The cylindrical shape of the section allows the anode part to be geometrically advantageous and stable on the receiving side, making it easier to connect the anode part to other components, for example to a complementarily designed receiving seat of the device for thermal spraying.
[0156] Media can be advantageously supplied to the plasma chamber via the cylindrical section.
[0157] The present anode section can be particularly well used as a nozzle for venting plasma loaded with powder particles if the nozzle area features a Laval nozzle section for more efficient acceleration and venting of the powder-particle-loaded plasma. A Laval nozzle section is understood to be a component with a Laval nozzle-like area.
[0158] Therefore, a device for thermal spraying can be built significantly more easily using the present anode part.
[0159] The Laval nozzle-like area can be integrated into the anode part in a particularly advantageous way if the Laval nozzle part is arranged at the smallest inner diameter of the anode part, in particular of its main channel.
[0160] This allows a typical Laval nozzle contour to be created within the anode section.
[0161] The proposed anode part can process a sufficiently large quantity of powder particles if the anode part has an inner diameter of 5 mm or more on the nozzle side, preferably 6 mm or more and particularly preferably 8 mm or more.
[0162] For the particularly efficient operation of a device for thermal spraying, an inner diameter of 8 mm has proven to be particularly advantageous.
[0163] Furthermore, an inner diameter of the anode part on the nozzle side of 10 mm or more has proven advantageous, preferably 15 mm or more and particularly preferably 20 mm or more.
[0164] Even the most powerful thermal spraying devices can be advantageously equipped with the present anode part if the anode part has an inner diameter of 120 mm or less on the nozzle side, preferably 80 mm or less and particularly preferably 40 mm or less.
[0165] Furthermore, the anode part advantageously has an inner diameter of 20 mm or less on the nozzle side, preferably 15 mm or less and particularly preferably 10 mm or less.
[0166] For the purpose of accommodating a cathode section or for realizing the individual functional areas, the anode section can be designed to be sufficiently voluminous if the anode section has an outer diameter of 10 mm or more, preferably 20 mm or more and particularly preferably 40 mm or more.
[0167] With an outer diameter of 300 mm or less, preferably 150 mm or less and particularly preferably 60 mm or less, the anode part can still be made sufficiently massive to withstand thermal stresses.
[0168] An outer diameter of 50 mm is particularly advantageous.
[0169] If the anode part has a total length of 20 mm or more, preferably 40 mm or more and particularly preferably 60 mm or more, the individual functional areas described above can be sufficiently long or large.
[0170] The present anode part can still be provided in a sufficiently compact form if the anode part has a total length of 150 mm or less, preferably 120 mm or less and particularly preferably 100 mm or less.
[0171] The overall length of the anode section can be selected, in particular, depending on the power or voltage of the thermal spraying device. A total length of 80 mm has proven to be particularly advantageous.
[0172] Furthermore, it is advantageous if the anode part has an anode cooling channel with a supply and a return, wherein the supply and the return each have a connection for connecting to a primary cooling device, which are each arranged in a region of the anode part facing away from the nozzle side.
[0173] The anode cooling channel enables very good cooling management of the present anode section.
[0174] The connections of the anode cooling channel are subject to less thermal stress in the area facing away from the nozzle side.
[0175] The connections can be located on the end face at the entry point. Preferably, the connections are arranged on the outer surface of the base body, so that the installation space on the receiving end face of the anode part is preferably available solely for the main channel and a corresponding sealing periphery.
[0176] Advantageously, the anode cooling channel is designed for a flow rate of cooling medium of approximately at least 5 1 / min and up to approximately 60 1 / min at pressures between 1 bar and approximately 20 bar, so that a sufficiently large cooling capacity can be covered at the anode part for most power ranges.
[0177] Good accessibility to the connections on the anode section can be ensured if each connection is located at least 20 mm away from the receiving side (receiving end face of the anode section) on the outer surface of the anode section's base body. This distance also ensures that the anode section can be easily mounted to another compatible component on its receiving side.
[0178] Sufficient stability of the anode section, for example with regard to high pressures, temperatures, temperature fluctuations, etc., can be well ensured if a wall is arranged between the anode feed and the anode return, which has a wall thickness of 0.3 mm or more, preferably 0.8 mm or more, and particularly preferably 1.2 mm or more.
[0179] Good thermal conductivity to a cooling medium can be achieved if the wall has a wall thickness of 10 mm or less, preferably 8 mm or less and particularly preferably 4 mm or less.
[0180] A wall thickness of 2 mm has proven to be particularly advantageous in order to achieve a particularly good ratio between stability and heat transfer capacity.
[0181] It is also advantageous if at least the anode lead-in has at least a partially ring-shaped contour along the longitudinal axis, which is optionally adapted to the contour of the nozzle area, in particular the Laval nozzle part.
[0182] The ring-shaped contour allows heat to be dissipated particularly well, especially from the nozzle chamber.
[0183] Heat dissipation can be further improved if the contour of the anode feed is adapted to or corresponds to the contour of the nozzle area or the Laval nozzle section. A similarly favorable situation exists with regard to the plasma chamber area, but also with regard to the receiving area, although the latter is not subjected to as high a thermal load as the plasma chamber area or the nozzle area.
[0184] The anode section can be designed even more advantageously if the anode cooling channel has a cross-section of 2 mm. 2 or more, preferably 4 mm 2 or more and especially preferably of 10 mm 2 or more.
[0185] A smaller cross-section of the anode cooling channel is particularly well-suited for lower-powered anode components. Generally, less cooling capacity is required.
[0186] Larger cross-sections, such as 100 mm 2, however, are particularly suitable for more robust anode sections.
[0187] Therefore, a cross-section of 75 mm for the anode cooling channel is usually sufficient. 2 or less, preferably 50 mm 2 or less and especially preferably of 25 mm 2 or less.
[0188] Another advantageous embodiment of the anode part provides that the anode part has another anode channel for guiding another medium, in particular a protective gas (inert gas), from an anode jacket surface to the nozzle side through the anode part, wherein the further anode channel is arranged concentrically around the nozzle area of the anode part.
[0189] This additional medium can also be used to cool the anode section. Preferably, the additional medium is used to "protect" the emitted plasma when it exits the anode section. Preferably, the additional medium is a so-called "shroud gas," in other words, a surrounding gas.
[0190] To minimize the reaction between the emitted plasma loaded with powder particles and the surrounding medium, it is advantageous to use an inert gas.
[0191] In order to enclose or encapsulate the plasma emitted from the anode section as completely as possible with the additional medium, it is advantageous if the additional anode channel on the nozzle side of the anode section has at least one annular gap opening or several annular gap openings for releasing the additional medium from the anode section.
[0192] If a distance of 0.2 mm or more, preferably 2 mm or more and particularly preferably 4 mm or more, is arranged between the at least one annular gap opening of the further anode channel and a nozzle opening of the nozzle area, the further medium can protect the emitted plasma from the surrounding atmosphere as far as possible immediately after it exits the anode part.
[0193] If the distance in this respect is 25 mm or less, preferably 15 mm or less and particularly preferably 8 mm or less, the anode part can still be manufactured with a sufficiently small circumference.
[0194] A sufficiently large output volume of further medium can be ensured at the anode section if at least one annular gap opening of the further anode channel has a total outlet area of 2 mm². 2 or more, preferably 6 mm 2 or more and especially preferably of 12 mm2 or more. Good compactness of the anode section can still be ensured if at least one annular gap opening has a total exit area of 50 mm². 2 or less, preferably 30 mm 2 or less and especially preferably of 20 mm 2 or less.
[0195] In summary, it can be said that both the cathode part and the anode part can be advantageously provided if the cathode part and / or the anode part are generated to 90% or more by means of an additive manufacturing process, preferably to 95% or more and particularly preferably entirely.
[0196] The cathode part and / or the anode part can be manufactured relatively cheaply if the cathode part and / or the anode part is made of copper or a copper alloy, in particular a copper-based alloy, especially to 90% or more, preferably to 95% or more and particularly preferably entirely.
[0197] In any case, it is particularly advantageous if the respective basic body, including its different functional areas, is monolithic, especially as a single monolithic block.
[0198] According to a fifth aspect, the object of the invention is also achieved by an arrangement consisting of a single cathode part and / or a single anode part, in which, for the axial injection of powder particles into a plasma, the single cathode part with its powder channel is arranged axially in front of a plasma chamber of the single anode part, wherein the single cathode part and the single anode part are arranged axially aligned with each other. This specific arrangement of the cathode part aligned in front of the anode part makes it possible to introduce or inject powder particles into the plasma chamber in front of the anode part, viewed in the direction of flow.
[0199] This has the advantage that the powder particles can remain within the plasma or a plasma bubble spreading in the plasma space of the anode part for as long as possible, allowing the powder particles to be exposed to the plasma heat much more intensively.
[0200] This allows a thermal spraying device to be operated much more energy-efficiently.
[0201] In this way, it can be achieved that the device can melt significantly more powder particles per unit of time using the plasma at the same temperature.
[0202] This arrangement can be particularly advantageously implemented with the cathode section and / or the anode section described here.
[0203] With a suitable design, the cathode and anode sections can be advantageously positioned and held relative to each other. For example, retaining elements, particularly in the form of electrical insulators, can be arranged on the receiving side of the anode section, enabling fixed positioning between the anode and cathode sections, so that the cathode section can be arranged, in particular axially in front of the plasma chamber of the anode section.
[0204] These retaining elements can also be monolithically formed together with the base body, provided they are electrically insulating. Alternatively, or possibly cumulatively, it is advantageous if the single cathode part and the single anode part are arranged relative to each other on a common central axis by means of at least one connecting element, in particular at least partially concentrically.
[0205] This external connecting part allows the cathode and anode sections to remain structurally simple.
[0206] The common central axis of the arrangement is preferably defined by the longitudinal axes of the cathode part and the anode part.
[0207] Advantageously, both the cathode part and the anode part have corresponding bearing surfaces in order to be reliably connected to the connecting part.
[0208] The connecting part can, for example, comprise a component of a device for thermal spraying, such as a housing area of the device.
[0209] The connecting part can advantageously be designed to be electrically insulating.
[0210] The connecting part can be designed particularly advantageously if the at least one connecting part has a plasma gas distributor ring element and / or a connecting sleeve part with a first bearing seat for supporting the cathode part and a second bearing seat for supporting the anode part.
[0211] The first and second bearing seats are arranged axially one behind the other on the at least one connecting part, for example with respect to the common central axis of the arrangement. According to a sixth aspect of the invention, the present problem also solves a feeding device for supplying powder particles to a device for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a base body and with a discharge side having a discharge opening for discharging the powder particles, wherein an additional ring element for generating an electric arc is arranged on the discharge side of the base body, wherein the additional ring element is made of a material that is different from the base body material.
[0212] Advantageously, the proposed feeding device can also be used as an electrode part, in particular as a cathode part.
[0213] The ring element on the feed device enables the latter to provide an arc for generating plasma in a more targeted and therefore trouble-free manner, even if the feed device is made of a less suitable material.
[0214] The proposed feeding device allows a thermal spraying apparatus to be implemented in a significantly more compact form than is currently common, provided that this apparatus requires both a cathode section and a powder feeding device.
[0215] The ring element is particularly well suited to generating an electric arc in accordance with the invention if the ring element is made of wool frame or a wool frame alloy.
[0216] Such a ring element in any case offers improved wear and / or heat protection at the feeding device. The wolfram alloy can, for example, comprise wolfram-lanthanum oxide, wolfram-cerium oxide, wolfram-thorium oxide, or the like.
[0217] If the ring element is arranged concentrically around the discharge opening for the discharge of the powder particles, the ring element can be integrated into the feeding device very easily in terms of construction.
[0218] In any case, it is advantageous if the feed device is arranged within a cathode section for generating an electric arc. This makes the implementation of the feed device particularly simple from a structural point of view.
[0219] Preferably, the feeding device is tubular and at least partially or completely integrated into the electrode part, in particular the cathode part, for example as a cylindrically designed tube part, in order to create a flow-technically advantageous powder channel.
[0220] Powder particles can be particularly advantageously fed into a plasma at the thermal spraying device if the powder particles are injected into the plasma in an area of a foot region of a formed plasma bubble.
[0221] The term “foot area” describes, within the meaning of the invention, the area in which a plasma gas ignited by means of an arc generated between the cathode part and an anode part spreads out in the plasma chamber, for example as a plasma bubble.
[0222] Therefore, it is advantageous if the feed device or a pipe section for guiding powder particles is arranged centrally in the electrode section or cathode section. This allows the powder particles to be introduced centrally into the plasma if the electrode section is positioned centrally in front of a plasma chamber for a plasma gas.
[0223] It should also be mentioned at this point that the feeding device can be further advantageously developed by means of features of the cathode section described here.
[0224] Therefore, it is advantageous if the feeding device includes a cathode section according to one of the features described here in this regard.
[0225] According to a seventh aspect of the invention, the problem is solved by a device for thermally spraying metallic and / or ceramic materials, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, comprising a central axis, a housing, a plasma chamber for plasma, a cathode part for generating an arc, an anode part for generating an arc, and a device for feeding powder particles into the plasma chamber, wherein the device is characterized in that the cathode part includes the device for feeding powder particles.
[0226] If the generation of an electric arc at or in the plasma chamber and the feeding of powder particles into the plasma chamber are realized on a single component or assembly, the device can not only be built much more compactly, but can also be operated significantly more energy-efficiently.
[0227] To generate the arc at or within the plasma chamber, the cathode and anode sections are arranged relative to each other in such a way that an arc can be initiated between them. Advantageously, the anode section encompasses the plasma chamber at least partially, preferably completely, so that the design of the present device can be even more compact.
[0228] The powder particles can distribute themselves particularly homogeneously and thus advantageously in the plasma if the anode part encompasses the plasma chamber, with the feeding device being arranged centrally in front of the plasma chamber.
[0229] This design can be achieved with minimal construction effort if the feeding device is arranged centrally or in the middle of the cathode part.
[0230] A central or centric injection of powder particles through the cathode part and into the plasma can be implemented particularly simply in the present device if the longitudinal axes of the plasma chamber, the cathode part, the anode part and the feeding device are aligned with each other.
[0231] Advantageously, these longitudinal axes are arranged to coincide with the central axis of the device, in particular the housing of the device, whereby powder particles and plasma can be advantageously brought into interaction with each other.
[0232] This also allows the cathode section with the feeding device and the anode section with the plasma chamber to be advantageously arranged in a straight line behind each other.
[0233] It is advantageous if the cathode part and the anode part are arranged in such a way that the powder particles introduced through the cathode part into the anode part are added axially in front of or at the entrance of the plasma chamber to the plasma generated in the plasma chamber.
[0234] Furthermore, it is advantageous if a discharge side of the cathode part, at which powder particles are brought out of the cathode part and into the plasma chamber of the anode part, is arranged to project at least partially into the anode part, wherein the discharge side of the cathode part is arranged centrally in front of the plasma chamber.
[0235] Such an arrangement allows powder articles to be injected directly from the cathode part into the plasma chamber, so that the device can also be designed to be very short.
[0236] If the discharge side of the cathode part at least partially limits the entrance of the plasma chamber, not only can a plasma foot be initiated at the entrance of the plasma chamber, but the powder particles can also be introduced into the plasma in the immediate vicinity of this plasma foot.
[0237] To generate the arc at the entrance of the plasma chamber, it is particularly advantageous if the discharge side of the cathode part has a ring element for generating an arc in interaction with the anode part.
[0238] This allows the discharge side to be used for introducing powder particles into the anode part on the one hand, and for generating a wear-resistant arc in interaction with the anode part on the other.
[0239] The ring element can not only form a more secure area of the cathode part, but can also simultaneously provide guiding functions for different media into the plasma chamber of the device, if the ring element forms an inner boundary for a channel carrying a plasma gas and an outer boundary for a channel carrying an inert gas.
[0240] The device can be built even more compactly if a receiving side of the anode part, on which the cathode part is arranged, has an inner wall area that tapers in the axial direction and a discharge side of the cathode part has an outer wall area that tapers in the axial direction, wherein the tapered outer wall area of the cathode part is arranged at least partially congruent with the tapered inner wall area of the anode part.
[0241] In the present case, the cathode part and the anode part can be arranged relative to each other in accordance with the invention if the device has exactly one single cathode part and / or exactly one single anode part.
[0242] In particular, a discharge opening of a powder channel of a device for feeding powder particles via the cathode part can be placed centrally in the anode part and in front of its plasma chamber if the device has only one cathode part which is exactly assigned to the anode part.
[0243] It is particularly advantageous if the one cathode part is not only assigned to exactly one plasma chamber of the one anode part, but also to exactly one Laval nozzle part of this anode part, so that the number of components or component groups used in the device can be reduced overall.
[0244] This is particularly advantageous because these components are usually wear parts that can be replaced easily and cost-effectively. The cathode and anode sections can be mounted differently within the device, for example, in separate housing sections.
[0245] It is advantageous if the device has a retaining element for holding the cathode part, wherein the retaining element surrounds the cathode part in a ring shape.
[0246] This allows, for example, a particularly simple and good centering of the cathode part on the central axis of the device, which appears to be easily controllable even with large temperature fluctuations.
[0247] Preferably, the retaining element is arranged in the front half of the cathode part, so that the retaining element can immediately limit the receiving area for the cathode part on the anode part.
[0248] It is particularly advantageous if the mounting element includes a plasma distributor ring element which, together with the cathode part, defines a working space of the device axially in front of and / or at the receiving area of the anode part.
[0249] The term "working space" here describes a space which is spatially limited by the plasma distributor ring element, the cathode part and the anode part.
[0250] If necessary, this working space can also comprise only the receiving space of the anode part, depending on the design of the device.
[0251] For this purpose, it is advantageous if the cathode part and the anode part are arranged at least partially overlapping each other on the centerline of the device, with the anode part being arranged radially further outwards than the cathode part. If the cathode part and the mounting element are jointly generated using an additive manufacturing process, the device for thermal spraying can be made even simpler in terms of construction, particularly if the mounting element is designed as a plasma distributor ring element.
[0252] The device can be further simplified in terms of design if the cathode part, the anode part, and the mounting element, in particular designed in the form of a plasma distributor ring element, are manufactured as a single component group using an additive manufacturing process, wherein the mounting element between the cathode part and the anode part is made at least partially of an insulator material in order to avoid an unwanted short circuit in the component group.
[0253] The device can be used in a variety of ways if it is configured to accelerate the powder-loaded plasma to 80 m / s or more, preferably to 200 m / s or more and particularly preferably to 500 m / s or more, and / or to accelerate the powder-loaded plasma to 1100 m / s or less, preferably to 800 m / s or less and particularly preferably to 700 m / s or less.
[0254] According to an eighth aspect, the problem also solves a method for manufacturing a cathode part and / or an anode part of a device for the thermal spraying of metallic and / or ceramic materials, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, in which the cathode part and / or the anode part are additively generated. Because the cathode part or the anode part is additively generated, it is possible to manufacture such often wear-intensive components cost-effectively, especially within the framework of largely automated series production.
[0255] Furthermore, it is particularly advantageous that additive manufacturing makes it possible to create even the most complex geometries, especially inside the cathode or anode section, for example additional structures for better conductivity of media, even in angled or curved channels with small diameters, as already described in detail above.
[0256] To avoid repetition, further specifications are referred to the features already described in detail above, from which further process variants can be derived.
[0257] In contrast to conventional subtractive manufacturing processes, the present device for thermal spraying can be provided in a particularly complex yet extremely compact manner using the additive manufacturing process.
[0258] According to a ninth aspect, the problem is also solved by a method for operating a device for the thermal spraying of metallic and / or ceramic materials, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, in which powder particles are fed into a plasma, in which the powder particles are at least partially melted by means of the plasma, and in which the powder-loaded plasma is accelerated onto a substrate, wherein the powder particles are introduced into the plasma through a cathode section. If the powder particles are introduced into the plasma through the cathode section, a structurally particularly simple introduction of the powder particles into the plasma is achieved.
[0259] In particular, this makes it possible to introduce powder particles into the area of a plasma foot, which is created at an arc generated by the cathode part and from which a plasma bubble spreads into the plasma chamber.
[0260] This allows the powder particles to be accelerated forward by the plasma for as long as possible, especially at maximum heat in the plasma chamber, whereby a particularly intimate and long heat transfer from the plasma to the powder particles can be achieved, which allows the powder particles to be melted even more advantageously.
[0261] Therefore, it is advantageous if powder particles are fed into the plasma at a foot region of the plasma.
[0262] By introducing powder particles through the cathode section, it is possible to introduce the powder particles into the plasma at the earliest possible time in a structurally uncomplicated manner.
[0263] An earlier introduction of powder particles into the plasma can be advantageously achieved if powder particles are introduced into the plasma gas before or at the plasma chamber.
[0264] This can involve unignited plasma gas, plasma gas that is just beginning to ignite, or plasma gas that is already partially ignited, particularly at the entrance of the plasma chamber. For example, powder particles and plasma gas for the plasma can be introduced together into the anode section at the receiving side of the anode section in front of the plasma chamber.
[0265] In any case, this allows powder particles to be fed into the plasma at a location opposite the nozzle outlet opening of the plasma.
[0266] A particularly preferred method variant provides that powder-loaded plasma flows through the plasma chamber and through a Laval nozzle-like region before the powder-loaded plasma exits from a nozzle outlet opening of the Laval nozzle-like region into the environment of the device.
[0267] This allows the powder particles to be heated by the plasma for as long as possible and to be carried and accelerated by the plasma for as long as possible.
[0268] It should also be noted that the described methods can be further supplemented by additional technical features described here, in particular by features of the cathode section, the anode section and / or the device, in order to further develop the methods advantageously, or to be able to represent or formulate the method specifications even more precisely.
[0269] According to a tenth aspect, the object of the invention is also solved by the use of a cathode part for injecting powder particles into plasma.
[0270] This allows the cathode part not only to functionally interact with an anode part to provide an arc for igniting plasma gas, but according to the invention the cathode part can also interact with powder particles to supply these powder particles to a plasma chamber, preferably directly at a plasma foot region.
[0271] Advantageously, the cathode part can therefore take on an additional function in a device for thermal spraying, which ultimately allows this device to be significantly further developed.
[0272] According to an eleventh aspect, the object of the invention is also solved by using an anode part as a dispersing part for dispersing powder particles and plasma gas or plasma, in particular as a Laval nozzle part for accelerating and ejecting plasma loaded with powder particles.
[0273] The mixing chamber section of the anode section allows for very effective mixing of powder particles with plasma gas. If the mixing chamber section also includes a plasma chamber in which plasma gas is ignited to form plasma, powder particles can be mixed with plasma there as well, either cumulatively or alternatively.
[0274] By means of the Laval nozzle part of the same anode part, the plasma loaded with powder particles can be accelerated particularly well in a structurally compact manner and thereby jetted out of the anode part at a correspondingly high speed, preferably with further acceleration.
[0275] In any case, it is advantageous that the anode part according to the invention comprises at least a mixing chamber part, preferably including a plasma chamber, as well as a Laval nozzle part.
[0276] According to a twelfth aspect of the invention, the problem is also solved by using a powder particle feeding device to generate an electric arc for plasma formation. It should be noted that, within the scope of this patent application, indefinite articles and indefinite numerical expressions such as "one...", "two...", etc., are generally to be understood as minimum specifications, i.e., "at least one...", "at least two...", etc., unless it is clear from the context or the specific text of a particular passage that only "exactly one...", "exactly two...", etc., is meant there.
[0277] It should be noted here that, within the context of the present patent application, the term "in particular" is always to be understood as introducing an optional, preferred feature. The term is not to be understood as "namely" or "indeed".
[0278] Further advantages, details and features of the invention will also become apparent from the exemplary examples explained below.
[0279] Components which are at least essentially identical in their function in the individual figures may be marked with the same reference symbols, whereby the components do not have to be referenced and explained in all figures.
[0280] The drawing shows:
[0281] Figure 1: schematically a sectional view of a cathode part with a powder channel for guiding powder particles through the cathode part;
[0282] Figure 2: schematically a sectional view of an anode part with a receiving area for at least partially receiving the cathode part, with a plasma chamber area and with a nozzle area; and Figure 3: schematically an arrangement of the cathode part shown in Figure 1 and the anode part shown in Figure 2 on a device for thermally spraying plasma-carried powder particles onto a substrate.
[0283] Figures 1 to 3 show essential components of a device 1 for thermal plasma spraying (see Figure 3) of metallic or ceramic material onto a substrate 2, which is not shown in detail here. These components include, in particular, a cathode part 100 (see Figure 1) and an anode part 200 (see Figure 3), which are arranged to interact with each other according to the arrangement 300 shown in Figure 3.
[0284] The cathode part 100 shown in Figure 1 has an elongated base body 102.
[0285] The basic body 102 defines a mean longitudinal axis 104 of the cathode part 100, which in this respect forms the central axis (not again referred to) of the cathode part 100.
[0286] The cathode part 100 is generated using an additive manufacturing process, which makes it advantageously designable, even from different materials in monolithic construction.
[0287] The cathode section 100 has a powder channel 106 through which powder particles 108, or more precisely a powder particle-gas mixture, can be guided through the cathode section 100. The powder particles 108, or rather the corresponding powder particle-carrier gas mixture, is a medium that can advantageously be guided through the cathode section 100.
[0288] The powder channel 106 extends with its longitudinal extent 106A along the longitudinal axis 104 from an inlet side 110 of the cathode part 100 to an outlet side 112 of the cathode part 100, whereby the powder particles 108 are guided from the inlet side 110 to the outlet side 112, along the longitudinal axis 104 of the cathode part 100 and in particular in the working direction 4 (see Figure 3) of the device 1.
[0289] In this embodiment, the powder channel 106 is designed to be many times longer in terms of its longitudinal extent 106A than in terms of its transverse extent 106B.
[0290] The powder channel 106 ends at the discharge side 112 with a discharge opening 106C .
[0291] The entry side 110 extends from the entry-side end face 110A of the cathode part 100 in the working direction 4. The entry side 110 comprises approximately one third of the total length 114 of the cathode part 100.
[0292] The discharge side 112 extends accordingly from the discharge-side end face 112A of the cathode part 100 in the opposite direction to the working direction 4. The discharge side 112 also comprises approximately one-third of the total length 114 of the cathode part 100, measured from the discharge-side end face 112A.
[0293] The cathode part 100 is predominantly conical on its discharge side 112, while otherwise it is cylindrical.
[0294] The powder channel 106 is formed on the base body 102 as a tube part 116, wherein the tube part 116 in this embodiment extends beyond the entry-side end face 110A.
[0295] In this embodiment, the cathode part 100 has at least one further channel 120, namely a cooling channel 122 for conveying a cooling medium and another channel 124 for conveying a bundle medium.
[0296] The cooling channel 122 has a supply line 122A and a return line 122B, each of which has a connection 122C and 122D respectively, in order to connect the cooling channel 122 to a primary cooling device of the apparatus 1 which is not shown here.
[0297] The two terminals 122C and 122D are each located in one area of the cathode part 100 facing the input-side end face 110A.
[0298] Both terminal 122C and terminal 122D are located on the outer shell surface 100A of the cathode part 100.
[0299] The outer surface 100A has a cylindrical area 100B and a conical area 100C, wherein a bearing seat 100D for a retaining element 5 (see Figure 3) for holding the cathode part 100 is provided on the cylindrical area 100B.
[0300] The cathode part 100 has an outer diameter 100D of 15 mm in the cylindrical area 100B.
[0301] The connection 122C of the supply line 122A is located closer to the input-side end face 110A than the connection 122D of the return line 122B, which is located between the connection 122C and the discharge side 112 on the base body 102.
[0302] This means that the supply line 122A is longer than the return line 122B.
[0303] In this exemplary embodiment, the cooling channel 122 has a cross-sectional area (not specified) of 60 mm². 2 The flow 122A and the return 122B are separated from each other by a wall (not explicitly shown) of 4 mm, which ensures good stability of the base body 102.
[0304] The forward flow 122A is located radially further inwards on the base body 102 than the return flow 122B. In other words, this means that the forward flow 122A is located closer to the longitudinal axis 104 and thus closer to the powder channel 106 than the return flow 122B, which runs closer to the outer surface 100A.
[0305] The return 122B follows the outer contour of the cathode part 100 or of the base body 102 thereof.
[0306] As a result, the cooling channel 122 is bent at least once in the direction of the longitudinal axis 104 at the predominantly conical discharge side 112 with respect to its return 122B, in order to be able to follow the conicity of the cathode part 100 in the area of the discharge side 112.
[0307] At the discharge side 112 of the cathode part 100, the cooling channel 122 has a cross-sectional expansion 126 in order to ensure increased cooling capacity there.
[0308] The cross-sectional expansion 126 connects the flow 122A and the return 122B to each other by means of an elongated ring cavity 122E.
[0309] The elongated annular cavity 122E is arranged in the base body 102 and can, in particular, improve the cooling of the ring element 130, to which the elongated annular cavity 122E directly abuts. The other channel 124 lies between the powder channel 108 and the cooling channel 122 and concentrically surrounds the powder channel 108.
[0310] Therefore, in this embodiment, the other channel 124 is designed as a ring channel (not referred to again) on the cathode part 100.
[0311] The other channel 124 runs continuously from a front channel opening 124A on the inlet side 110 or on the corresponding front end face 110A of the cathode part 100 to a rear channel opening 124B, which is located on the outlet side 112 of the cathode part 100, more precisely on the outlet-side end face 112A.
[0312] The front channel opening 124A is therefore located at a height between the radially outermost connections 122C, 122D and the powder channel 106.
[0313] The rear channel opening 124B of the other channel 124 lies between the powder channel 106 and an additional ring element 130 generated on the discharge side 112.
[0314] This ring element 130 essentially assumes the function of a cathode ring element (not referred to again) on which an arc 6 (see Figure 3) can mainly and preferably establish itself between the cathode part 100 and the anode part 200.
[0315] In this exemplary embodiment, the ring element 130 consists of a material different from the rest of the base body 102 of the cathode part 100, such as wool, which makes the ring element 130 more thermally stable and also more wear-resistant than the rest of the cathode part 100. The channels 120, such as the powder channel 106, the cooling channel 122, or the other channel 124, can be equipped with an additional guide element 134 (shown schematically only as an example with regard to the cooling channel 122) in order to facilitate the passage of the respective medium through the respective channel 106, 122, or 124.
[0316] For example, the additional guide element 134 can comprise one or more guide vane parts (not shown) to impart a swirl motion to the respective medium in addition to the axial motion in the working direction 4, while the medium flows in the direction of the longitudinal axis 104 through the corresponding channel 106, 122 or 124.
[0317] The additional guiding element 134 can comprise a helical structure.
[0318] Furthermore, the additional guiding element 134 with the helical structure, the guiding vane part or the like can also immediately embody a support structure (not shown and described separately) in the respective channel 106, 122 or 124, thereby positively influencing the structural integrity of the cathode part 100.
[0319] For this purpose, the additional guiding element 134 is designed as a physical unit with the basic body 102 of the cathode part.
[0320] Alternatively, the additional guide element 134 can also be fixed but loosely inserted and arranged within the respective channel 106, 122 or 124, for example as an articulated spring element.
[0321] Overall, the cathode part 100 shown and explained in this exemplary embodiment is generated in its entirety as a monolithic block 140. It should be further explained here that the base body 102 described above, with the powder channel 106 located therein and, in particular, with the tube part 116, can be considered a feeding device by means of which powder particles 108 can be introduced or injected into a plasma 8 (see Figure 3; shown only schematically) of the device 1.
[0322] According to the illustration in Figure 2, the anode part 200 is now shown in more detail.
[0323] The anode part 200 has a base body 202, by means of which a central longitudinal axis 204 of the anode part 200 is defined. This longitudinal axis 204 thus forms the central axis (not again referred to) of the anode part 200.
[0324] The anode part 200 is also generated using an additive manufacturing process, which also makes it advantageously possible to design this anode part 200, even from different materials in monolithic construction.
[0325] The anode part 200 has a centrally arranged main channel 206 and at least one further channel 208, namely in this embodiment a radially further outward placed anode cooling channel 210 and another radially further outward located channel 212.
[0326] The main channel 206 runs from a receiving side 214 of the anode part 200 to a nozzle side 216 of the anode part 200 .
[0327] The receiving side 214 extends from the receiving-side end face 214A of the anode part 200 in the working direction 4 of the device. The receiving side 214 comprises approximately one-third of the total length 218 of the anode part 200.
[0328] Accordingly, the nozzle side 216 extends from the nozzle-side end face 216A of the cathode part 100 in the opposite direction of operation 4. The nozzle side 216 also comprises approximately one-third of the total length 218 of the anode part 200, measured from the nozzle-side end face 216A.
[0329] The total length 218 is 90 mm in this example.
[0330] The anode part 200 has a receiving area 220 with a receiving chamber 220A for at least partially receiving a cathode part 100 within the anode part 200.
[0331] Furthermore, the anode part 200 has a plasma chamber area 222 with a cylindrical plasma chamber 222A for generating and maintaining plasma 8 within the anode part 200.
[0332] In addition, the anode part 200 also has a Laval nozzle-like area 226 with a Laval nozzle part 226A for accelerating powder particle 108 loaded plasma 8 within the anode part 200 and subsequently nozzleing out this powder particle 108 loaded plasma 8 .
[0333] In terms of construction, these three essential functional areas – recording area 220 with the recording chamber 220A, plasma chamber area 222 with the plasma chamber 222A and Laval nozzle-like area 226 with the Laval nozzle part 226A – are designed solely through the main channel 206 of the anode part 200.
[0334] Here, the receiving chamber 222A and the plasma chamber 222A merge directly into one another at an interface 231A. The plasma chamber 222A and the Laval nozzle part 226A merge into one another at a further interface 231B.
[0335] Preferably, no other areas or components are arranged between the receiving chamber 222A and the plasma chamber 222A on the one hand, and between the plasma chamber 222A and the Laval nozzle part 226A on the other.
[0336] The recording area 220 is designed to record exactly one single cathode part 100.
[0337] In particular, the receiving area 220 is cylindrical in one section 220B facing the receiving side 214 and conical in another section 220C facing the plasma chamber area 222.
[0338] By providing that the receiving area 220 of the anode part 200 is designed so that, in proper use, the cathode part 100 is at least partially arranged therein, the receiving area 220 advantageously also forms an entry opening 228 for the entry of powder particles 108.
[0339] Since the intake area 220 is also used to supply plasma gas to generate plasma 8 into the plasma chamber 222A, the intake area 220 also forms an inlet opening 230 for introducing the plasma gas into the plasma chamber 222A.
[0340] The Laval nozzle part 226A can be generated particularly advantageously within the main channel 206 if the Laval nozzle part 226A is arranged at the smallest inner diameter 232 of the anode part 200. In this exemplary embodiment, the anode part 200 has an inner diameter 234 of 8 mm at its nozzle side 216 with respect to the nozzle opening 226B of the main channel.
[0341] Furthermore, the anode part 200 has a maximum outer diameter of 236 of 50 mm.
[0342] The aforementioned anode cooling channel 210 has a supply line 210A and a return line 210B, wherein a supply line connection 210C is provided for the supply line 210A and a return line connection 210D for the return line 210B on the shell surface 200A of the anode part 200.
[0343] At least the inlet 210A of the anode cooling channel 210 is adapted to the design of the main channel 206.
[0344] The flow 210A and the return flow 210B merge into each other in a ring cavity 210E generated in the base body 202.
[0345] The annular cavity 210E is formed on the nozzle side 216, which allows for particularly good cooling effects to be achieved there.
[0346] The other anode channel 212 has a channel connection 212A also located on the jacket surface 200A for introducing protective gas, which exits again from the other anode channel 212 at the nozzle-side end face 216A, namely from an annular gap opening 212B.
[0347] The annular gap opening 212B is spaced a few millimeters apart from the nozzle opening 226B by a distance of 240.
[0348] According to Figure 3, an arrangement 300 consisting of the single cathode part 100 and a single anode part 200 is shown on the device 1, wherein the cathode part 100 is oriented centrally relative to the anode part 200.
[0349] This means that the longitudinal axes 104 and 204 of cathode part 100 and anode part 200 are aligned with each other and, in particular, run identically with the central axis 12 of the device 1. This also means that the powder channel 106 of the feed device is arranged centrally in front of the plasma chamber 222A.
[0350] The cathode part 100 and the anode part 200 remain in position relative to each other by means of a connecting part 302 of the arrangement 300.
[0351] The connecting part 302 comprises a plasma gas distributor ring element 302A and a connecting sleeve part 302B, the latter having a first bearing seat 304 for supporting the cathode part 100 and a second bearing seat 306 for supporting the anode part 200.
[0352] The bearing seats 304 and 306 are arranged axially one behind the other on the connecting sleeve part 302B.
[0353] The connecting part 302 can advantageously be used to implement the retaining element 5 for holding the cathode part 100 on the device 1.
[0354] The device 1 thus set up for thermally spraying metallic and / or ceramic material onto the substrate 2, such as the plasma 8 loaded with powder particles 108, can be built in a particularly simple way and can also be operated extremely efficiently.
[0355] The device 1 further comprises a housing 14, which may include as a mounting element 5 in particular the described connecting sleeve part 302B, wherein the device 1 is of a particularly simple design, since the cathode part 100 immediately includes the device for feeding powder particles 108 into the plasma chamber 222A of the anode part 200.
[0356] Here, the discharge side 112 of the cathode section 100 limits the inlet of the plasma chamber 222A at least partially.
[0357] The connecting part 302 or components thereof define a working space 1A of the device 1 between the cathode part 100 and the anode part 200, in particular at the receiving side 214 of the anode part 200.
[0358] The device makes it possible to introduce powder particles 108 through the cathode part 100 into the plasma 8.
[0359] The powder particles 108 can be introduced into the plasma 8 at a foot region 8A of the plasma 8.
[0360] In any case, the powder particles 108 can be fed into a plasma gas in front of or at the plasma chamber 222A.
[0361] The powder-loaded plasma 8 flows through the plasma chamber 222A and then through the Laval nozzle-like section 226 before exiting the nozzle outlet opening 226B of the Laval nozzle-like section 226 into the environment 15 of the device 1. Reference numeral list
[0362] 1 Device for thermal plasma spraying
[0363] 1A workroom
[0364] 2 Substrat
[0365] 4 Working direction
[0366] 5 Mounting element
[0367] 6 arcs
[0368] 8 Plasma
[0369] 8A Foot area
[0370] 12 Central axis
[0371] 14 cases
[0372] 15 surroundings
[0373] 100 Cathode section
[0374] 100A shell area
[0375] 100B cylindrical area
[0376] 100C conical area
[0377] 100D seat or bearing seat
[0378] 100E outer diameter
[0379] 102 Basic bodies
[0380] 104 Longitudinal axis
[0381] 106 Powder channel
[0382] 106A Longitudinal extent
[0383] 106B Transverse extension
[0384] 106C Discharge opening
[0385] 108 powder particles
[0386] 110 entry page
[0387] 110A entry-side (front) end face
[0388] 112 Exit page
[0389] 112A discharge side (rear) end face
[0390] 114 Total length
[0391] 116 Pipe section
[0392] 120 at least one more channel
[0393] 122 Cooling channel 122A Supply
[0394] 122B Return
[0395] 122C Flow connection
[0396] 122D Return connection
[0397] 122E elongated ring cavity
[0398] 124 other channel or inert gas-conducting channel
[0399] 124A front channel opening
[0400] 124B rear channel opening or outlet opening
[0401] 126 Cross-sectional expansion
[0402] 130 ring element
[0403] 134 additional guide element
[0404] 200 anode section
[0405] 200A shell area
[0406] 202 Basic body
[0407] 204 Longitudinal axis
[0408] 206 Main Channel
[0409] 208 at least one more channel
[0410] 210 Anode cooling channel
[0411] 210A Lead
[0412] 210B Return
[0413] 210C Flow connection
[0414] 210D Return connection
[0415] 210E Ring cavity
[0416] 212 other channel
[0417] 212A Channel connection
[0418] 212B Annular gap opening
[0419] 214 Recording page
[0420] 214A receiving-side end face
[0421] 216 Nozzle side
[0422] 216A nozzle-side end face
[0423] 218 Total length
[0424] 220 recording area
[0425] 220A Recording Chamber
[0426] 220B cylindrical section 220C conical section
[0427] 222 Plasma chamber area
[0428] 222A Plasma Chamber
[0429] 222B Entrance
[0430] 226 Laval nozzle-like area or nozzle area
[0431] 226A Laval nozzle part
[0432] 226B Nozzle opening
[0433] 228 Entry opening
[0434] 230 Inlet opening or plasma gas-carrying channel
[0435] 231A first interface
[0436] 231B further boundary surface
[0437] 232 smallest inner diameter
[0438] 234 Inner diameter at the nozzle-side end face
[0439] 236 outer diameter
[0440] 240 distance
[0441] 300 arrangement
[0442] 302 Connecting part
[0443] 302A Plasma gas distributor ring element
[0444] 302B outer connecting sleeve part
[0445] 304 first warehouse location
[0446] 306 second warehouse location
Claims
Patent claims 1. Cathode part (100) for a device (1) for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a base body (102) having a longitudinal axis (104) , with a powder channel (106) extending along the longitudinal axis (104) for guiding powder particles (108) from an input side (110) of the cathode part (100) to an output side (112) of the cathode part (100) through the cathode part (100).
2. Cathode part (100) for a device (1) for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a base body (102) having a longitudinal axis (104) , with at least one channel (106, 120, 122, 124) for guiding a medium through the cathode part (100), characterized in that the cathode part (100) is at least partially generated by means of an additive manufacturing process.
3. Cathode part (100) according to claim 1 or 2, characterized in that the cathode part has at least one further channel (120, 122, 124) for guiding a further medium through the cathode part (100), in particular the at least one further channel (120, 122, 124) is arranged at least partially around the powder channel (106).
4. Cathode part (100) according to claims 1 to 3, characterized in that at least one channel (106, 120, 122, 124) of the cathode part (100), in particular a powder channel (106), has a longitudinal extension (106A) which is formed in the direction of the longitudinal axis (104) several times longer than a transverse extension (106B) of the at least one channel (106, 120, 122, 124) transverse to the longitudinal axis (104).
5. Cathode part (100) according to one of claims 1 to 4, characterized in that at least one channel (106) of the cathode part (100), in particular a powder channel (106), has an acceleration section for accelerating powder particles (108), in particular a powder particle-carrier gas mixture.
6. Cathode part (100) according to one of claims 1 to 5, characterized in that the cathode part (100) has a ring element (130) on its discharge side (112), which is in particular arranged in a way that is snugly attached to the base body (102).
7. Cathode part (100) according to claim 6, characterized in that the ring element (130) is made of tungsten or a tungsten alloy.
8. Cathode part (100) according to claim 6 or 7, characterized in that the ring element (130) has a wall thickness of 0.5 mm or more, preferably 1.5 mm or more and particularly preferably 3 mm or more, and / or has a wall thickness of 5 mm or less, preferably 4 mm or less and particularly preferably 3.5 mm or less.
9. Cathode part (100) according to one of claims 1 to 8, characterized in that the cathode part (100) has a cooling channel (122) with a supply (122A) and with a return (122B), each of which has a connection (122C, 122D) for connecting to a primary cooling device, each of which is arranged in a region of the cathode part (100) facing the input side (110).
10. Cathode part (100) according to claim 9, characterized in that the cooling channel (122) has a cross-sectional area of 2 mm² 2 or more, preferably 4 mm 2 or more and especially preferably of 10 mm 2 or more, and / or a cross-sectional area of 75 mm² 2 or less, preferably 50 mm 2 or less and especially preferably of 25 mm 2 or less.
11. Cathode part (100) according to claim 9 or 10, characterized in that a wall is arranged between the feed (122A) and the return (122B) which has a wall thickness of 0.3 mm or more, preferably 0.8 mm or more and particularly preferably 1.2 mm or more, and / or has a wall thickness of 5 mm or less, preferably 4 mm or less and particularly preferably 3 mm or less.
12. Cathode part (100) according to one of claims 1 to 11, characterized in that the cathode part (100) has another channel (124) for guiding a further medium from the input side (110) to the discharge side (112) through the cathode part (100), in particular the other channel (124) is arranged concentrically around the powder channel (106).
13. Cathode part (100) according to claim 12, characterized in that the other channel (124) has an outlet opening (124B) on the discharge side (112) of the cathode part (100) for the medium to exit from the cathode part (100).
14. Cathode part (100) according to claim 13, characterized in that the outlet opening (124B) is arranged radially further inside a ring element (130) which is arranged on the discharge side (112) of the cathode part (100).
15. Cathode part (100) according to one of claims 1 to 14, characterized in that a cooling channel (122) of the cathode part (100) and / or another channel (124) of the cathode part (100) each has at least one additional guiding element (134) for guiding the respective medium.
16. Cathode part (100) according to claim 15, characterized in that the at least one additional guide element (134) has a wall thickness of 0.1 mm or more, preferably 1 mm or more and particularly preferably 2 mm or more, and / or has a wall thickness of 5 mm or less, preferably 4 mm or less and particularly preferably 3 mm or less.
17. Cathode part (100) according to claim 15 or 16, characterized in that the at least one additional guide element (134) along the longitudinal axis (104) of the base body (102) has a length of 2 mm or more, preferably 4 mm or more and particularly preferably 6 mm or more, and / or has a length of 20 mm or less, preferably 16 mm or less and particularly preferably 12 mm or less.
18. Cathode part (100) according to one of claims 15 to 17, characterized in that the at least one additional guide element (134) for applying a swirling motion to the respective medium comprises a guide vane part or several guide vane parts.
19. Cathode part (100) according to one of claims 15 to 18, characterized in that the at least one additional guiding element (134) has a helical structure.
20. Cathode part (100) according to claim 19, characterized in that the helical structure along the longitudinal axis (104) of the cathode part (100) has a pitch of 1 mm or more, preferably 5 mm or more and particularly preferably 15 mm, and / or has a pitch of 50 mm or less, preferably 40 mm or less and particularly preferably 30 mm or less.
21. Cathode part (100) according to one of claims 15 to 20, characterized in that the at least one additional guiding element comprises a support structure of the cathode part (100).
22. Cathode part (100) according to one of claims 1 to 21, characterized in that the cathode part (100) has an outer diameter (100E) of 5 mm or more, preferably of 10 mm or more and particularly preferably of 15 mm or more, and / or has an outside diameter (100E) of 30 mm or less, preferably 25 mm or less and particularly preferably 20 mm or less.
23. Cathode part (100) according to one of claims 1 to 22, characterized in that the cathode part (100) has at least one seat (100D) on its outer surface (100A) for a retaining element (5) for holding the cathode part (100) in a fixed position on a housing (14) of the device (1) for thermal spraying, wherein in particular the seat (100D) is generated by means of an additive manufacturing process.
24. Cathode part (100) according to one of claims 1 to 23, characterized in that the cathode part (100), in particular the base body (102) thereof, and / or at least one channel (106, 120, 122, 124) thereof, in particular the powder channel (106), the fluid channel (122, 124), and / or the ring element (130) thereof, are formed monolithically, in particular as a single monolithic block.
25. Anode section (200) for a device (1) for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, comprising a base body (202) having a longitudinal axis (204) and a main channel (206) extending along the longitudinal axis (204) and with at least one further channel (208) for guiding a further medium through the anode section (200), wherein the at least one further channel (208) is arranged at least partially around the main channel (206), and wherein the main channel (206) of the base body (202) alone provides a receiving area (220) for at least partially receiving a cathode section (100) within the anode section (200) and a plasma chamber area (222) for generating plasma (8) within the anode section (200), in particular entirely designed, in particular the main channel (206) of the base body (202) forms a Laval nozzle-like area (226) for Acceleration of powder particle (108) loaded plasma (8) within the anode part (200) and subsequent jetting of powder particle (108) loaded plasma (8).
26. Anode part (200) for a device (1) for thermal spraying, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, comprising a base body (202) having a longitudinal axis (204), a receiving side (214) having a receiving area (220) for at least partially receiving a cathode part (100), a nozzle side (216), in particular having a Laval nozzle-like area (226) for spraying plasma (8), in particular plasma (8) loaded with powder particles (108), a channel-like plasma chamber area (222) for generating plasma (8), which is arranged between the receiving side (214) and the nozzle side (216), and at least one channel (206, 208, 210, 212) for Guiding at least one medium through the anode part (200), characterized in that the anode part (200) is at least partially generated by means of an additive manufacturing process.
27. Anode part (200) according to claim 25 or 26, characterized in that the receiving area (220) is configured to receive exactly one single cathode part (100), in particular an axial three-cathode burner part.
28. Anode part (200) according to one of claims 25 to 27, characterized in that the anode part (200) has an introduction opening (230) for introducing plasma gas for generating plasma (8), wherein the receiving area (220) comprises this introduction opening (230).
29. Anode part (200) according to one of claims 25 to 28, characterized in that the anode part (200) has an inlet opening (228) for introducing powder particles (108) to generate has powder particle loaded plasma (8), wherein the receiving area (220) of the anode part (200) includes this entry aperture (228).
30. Anode part (200) according to claim 28 or 29, characterized in that the insertion opening (230) and / or the entry opening (228) are arranged in front of the plasma chamber area (222) of the anode part (200).
31. Anode part (200) according to one of claims 28 to 30, characterized in that the insertion opening (230) and the entry opening (228) are identical.
32. Anode part (200) according to one of claims 25 to 31, characterized in that the receiving area (220) is cylindrical on a section (220B) facing the receiving side and conical on a further section (220C) facing the plasma chamber area.
33. Anode part (200) according to one of claims 25 to 32, characterized in that the nozzle area (226) has a Laval nozzle part (226A) for more favorable acceleration and ejection of plasma (8) loaded with powder particles (108).
34. Anode part (200) according to claim 33, characterized in that the Laval nozzle part (226A) is arranged at the smallest inner diameter (232) of the anode part (200), in particular of the main channel (206) thereof.
35. Anode part (200) according to one of claims 25 to 34, characterized in that the anode part (200) has an inner diameter (234) of 5 mm or more at the nozzle side (216), preferably 6 mm or more and particularly preferably 8 mm or more, and / or has an inner diameter (234) of 120 mm or less, preferably 80 mm or less and particularly preferably 40 mm or less.
36. Anode part (200) according to one of claims 25 to 35, characterized in that the anode part (200) has an outer diameter (236) of 10 mm or more, preferably of 20 mm or more and particularly preferably of 40 mm or more, and / or has an outer diameter (236) of 300 mm or less, preferably of 150 mm or less and particularly preferably of 60 mm or less.
37. Anode part (200) according to one of claims 25 to 36, characterized in that the anode part (200) has a total length (218) of 20 mm or more, preferably 40 mm or more and particularly preferably 60 mm or more, and / or has a total length (218) of 150 mm or less, preferably 120 mm or less and particularly preferably 100 mm or less.
38. Anode part (200) according to one of claims 25 to 37, characterized by an anode cooling channel (210) with a supply (210A) and with a return (210B), wherein the supply (210A) and the return (210B) each have a connection (210C, 210D) for connecting to a primary cooling device, which are each arranged in a region of the anode part (200) facing away from the nozzle side (216).
39. Anode part (200) according to claim 38, characterized in that a wall is arranged between the forward (210A) and the return (210B) which has a wall thickness of 0.3 mm or more, preferably 0.8 mm or more and particularly preferably 1.2 mm or more, and / or has a wall thickness of 10 mm or less, preferably 8 mm or less and particularly preferably 4 mm or less.
40. Anode part (200) according to claim 38 or 39, characterized in that at least the lead-in (210A) has an at least partially annular contour along the longitudinal axis (204), which is optionally adapted to the contour of the nozzle area (226), in particular the Laval nozzle part (226A).
41. Anode part (200) according to one of claims 38 to 40, characterized in that the anode cooling channel (210) has a cross-section of 2 mm 2 or more, preferably 4 mm 2 or more and especially preferably of 10 mm 2 or more, and / or a cross-section of 75 mm 2 or less, preferably 50 mm 2 or less and especially preferably of 25 mm 2 or less.
42. Anode part (200) according to one of claims 25 to 41, characterized in that the anode part (200) has another anode channel (212) for guiding a further medium, in particular a protective gas, from an anode jacket surface (200A) to the nozzle side (216) through the anode part (200), wherein the other anode channel (212) is arranged concentrically around the nozzle area (226) of the anode part (200).
43. Anode part (200) according to claim 42, characterized in that the other anode channel (212) on the nozzle side (216) of the anode part (200) has at least one annular gap opening (212B) or several annular gap openings (212B) for releasing the further medium from the anode part (200).
44. Anode part (200) according to claim 43, characterized in that a distance (240) of 0.2 mm or more is arranged between the at least one annular gap opening (212B) of the other anode channel (212) and a nozzle opening (226B) of the nozzle area (226), preferably 2 mm or more and particularly preferably 4 mm or more, and / or a distance (240) of 25 mm or less is arranged, preferably 15 mm or less and particularly preferably 8 mm or less.
45. Anode part (200) according to claim 43 or 44, characterized in that the at least one annular gap opening (212B) of the other anode channel (212) has a total exit area of 2 mm 2 or more, preferably 6 mm 2 or more and especially preferably of 12 mm 2 or more, and / or a total outlet area of 50 mm 2 or less, preferably from 30 mm 2 or less and especially preferably of 20 mm2 or less.
46. Arrangement (300) comprising a single cathode part (100), in particular a cathode part (100) according to any one of claims 1 to 24, and / or a single anode part (200), in particular an anode part (200) according to any one of claims 25 to 45, wherein, for the axial injection of powder particles (108) into a plasma (8), the single cathode part (100) with its powder channel (106) is arranged axially in front of a plasma chamber (222A) of the single anode part (200), wherein the single cathode part (100) and the single anode part (220) are arranged axially aligned with each other.
47. Arrangement (300) according to claim 46, characterized in that the single cathode part (100) and the single anode part (200) are arranged relative to each other by means of at least one connecting part (302) on a common central axis (12), in particular at least partially concentric relative to each other.
48. Device (1) for thermal spraying of metallic and / or ceramic spray material, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, with a central axis (12), with a housing, with a plasma chamber for plasma (8), with a cathode part (100) for generating an electric arc (6), in particular according to one of claims 1 to 24, in particular with an anode part (200) for generating an electric arc (6), in particular according to one of claims 25 to 45, and with a device for supplying powder particles (108) into the plasma chamber (222A), characterized in that the cathode part (100) comprises the device for supplying powder particles (108).
49. Device (1) according to claim 48, characterized in that the anode part (200) comprises the plasma chamber (222A), wherein The feeding device is arranged centrally in front of the plasma chamber (222A).
50. Device (1) according to claim 48 or 49, characterized in that the longitudinal axes (104, 204) of the plasma chamber (222A) , the cathode part (100) , the anode part (200) and the feeding device are arranged in alignment with each other.
51. Device (1) according to one of claims 48 to 50, characterized in that a discharge side (112) of the cathode part (100), at which powder particles (108) are discharged from the cathode part (100) and brought into the plasma chamber of the anode part (200), is arranged to project at least partially into the anode part (200), wherein the discharge side (112) of the cathode part (100) is arranged centrally in front of the plasma chamber (222A).
52. Device (1) according to claim 51, characterized in that the discharge side (112) of the cathode part (100) at least partially limits the inlet (222B) of the plasma chamber (222A).
53. Device (1) according to claim 51 or 52, characterized in that the discharge side (112) of the cathode part (100) has a ring element (130) for generating an electric arc (6) in interaction with the anode part (200).
54. Device (1) according to claim 53, characterized in that the ring element (130) forms an inner boundary for a channel (230) carrying a plasma gas and an outer boundary for a channel (124) carrying an inert gas.
55. Device (1) according to one of claims 48 to 54, characterized in that a receiving side (214) of the anode part (200) on which the cathode part (100) is arranged has an inner wall region tapering in the axial direction and a discharge side (112) of the cathode part (100) has a surface tapering in the axial direction having an axially tapered outer wall area, wherein the tapered outer wall area of the cathode part (100) is arranged at least partially congruent with the tapered inner wall area of the anode part (200).
56. Device (1) according to one of claims 48 to 55, characterized in that the device (1) has exactly one single cathode part (100) and / or exactly one single anode part (200).
57. Device (1) according to one of claims 48 to 56, characterized in that the device (1) has a retaining element (5) for holding the cathode part (100), wherein the retaining element (5) surrounds the cathode part (100) in a ring shape.
58. Device (1) according to claim 57, characterized in that the retaining element (5) comprises a plasma gas distributor ring element (302A) which, together with the cathode part (100) a working space (1A) of the device (1) axially in front of and / or at the receiving area of the anode part (200).
59. Device (1) according to one of claims 48 to 58, characterized in that the device (1) is configured to accelerate the powder-loaded plasma (8) to 80 m / s or more, preferably to 200 m / s or more and particularly preferably to 500 m / s or more, and / or to accelerate the powder-loaded plasma (8) to 1100 m / s or less, preferably to 800 m / s or less and particularly preferably to 700 m / s or less.
60. Method for manufacturing a cathode part (100) and / or an anode part (200) of a device (1) for thermal spraying of metallic and / or ceramic spray material, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, in particular a cathode part (100) according to one of claims 1 to 24. and / or an anode part (200) according to one of claims 25 to 45, wherein the cathode part (100) and / or the anode part (200) are additively generated.
61. Method for operating a device (1) for thermal spraying of metallic and / or ceramic spray material, in particular for atmospheric plasma spraying and / or protective gas plasma spraying and / or vacuum plasma spraying, in which powder particles (108) are supplied to a plasma (8), in which the powder particles (108) are at least partially melted by means of the plasma (8), and in which the powder-loaded plasma (8) is accelerated onto a substrate (2), characterized in that the powder particles (108) are introduced into the plasma (8) through a cathode part (100).
62. Method according to claim 61, characterized in that powder particles (108) are supplied to the plasma (8) at a foot region (8A) of the plasma.
63. Method according to claim 61 or 62, characterized in that powder particles (108) are supplied to a plasma gas upstream of or at the plasma chamber (222A).
64. Method according to claims 61 to 63, characterized in that powder-loaded plasma (8) flows through the plasma chamber (222A) and through a Laval nozzle-like area (226) before the powder-loaded plasma (8) exits from a nozzle outlet opening (226B) of the Laval nozzle-like area (226) into the environment (15) of the device (1).
65. Use of a cathode part (100) for injecting powder particles (108) into plasma (8) .
66. Use of an anode part (200) as a dispersing part for dispersing powder particles (108) and plasma gas or plasma (8), in particular as a Laval nozzle part (226A) for accelerating and ejecting plasma (8) loaded with powder particles (108).
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