Receiving device for receiving a workpiece, laser machining system comprising same, and use of the receiving device and / or of the laser machining system in a laser machining process

Abstract

The present invention relates to a receiving device for receiving a workpiece for a laser machining process performed on the workpiece by means of a laser beam, comprising: a support element for supporting a workpiece; and at least one cooling device for actively cooling the workpiece. The invention also relates to a laser machining system, comprising the receiving device, for carrying out a laser machining process for machining a workpiece by means of a laser beam, and to the use of the receiving device and of the laser machining system.

Description

[0001] Precitec GmbH & Co. KG, Case: PR 975 WO

[0002] Holding device for holding a workpiece, laser processing system with the same, and use of the holding device and / or the laser processing system in a laser processing process

[0003] The present disclosure relates to a holding device for receiving a workpiece, a laser processing system with the holding device, and the use of the holding device and / or the laser processing system in a laser processing method. The holding device particularly includes a cooling device for actively cooling a workpiece.

[0004] Technical background

[0005] To process a workpiece using a laser beam (laser processing or laser machining), a laser processing system is used, which includes a laser processing head for directing the laser beam onto the workpiece. The laser processing head can include beam guidance and beam shaping optics. Furthermore, the laser processing head can include focusing optics for focusing the laser beam onto the workpiece. A laser light source is used to generate the laser beam. The laser beam is guided to the laser processing head by means of an optical fiber.

[0006] The laser processing method can be an additive manufacturing process, such as laser cladding, particularly laser wire cladding. In laser wire cladding, a wire-shaped (cladding) material is melted by means of a laser beam and bonded to at least one workpiece (also referred to as a substrate). This allows, for example, structures to be welded onto the workpiece. Furthermore, multiple workpieces can be welded together using the material. The laser processing head directs the laser beam into a processing area on the workpiece. A wire feeder feeds the wire (also referred to as welding wire) into the processing area. The wire feeder can be located on or within the laser processing head, or even be part of it. In coaxial laser (wire) cladding, the wire is melted by means of one or more coaxially supplied laser beams.

[0007] Laser processing methods, particularly laser cladding, can lead to problems caused by excessive heat input into the workpiece or insufficient heat dissipation. One such problem is the occurrence of undesirable deformations and / or discoloration on the underside or back of the workpiece. Other undesirable consequences include enlarged heat-affected zones or areas on the workpiece with undesirable features. (Precitec GmbH & Co. KG, Case: PR 975 WO)

[0008] Material properties, such as reduced strength, are particularly relevant when the affected areas of the workpiece are part of a visible surface and / or when these areas are subjected to high mechanical stress later on.

[0009] Common methods for cooling a workpiece involve applying a cooling medium, usually water or a gas, directly to the workpiece. However, immersing the workpiece in water or applying water to the workpiece can lead to oxidative effects. For example, a weld contour can be negatively affected. Furthermore, handling the workpiece in the medium is cumbersome. This also results in high consumption of the cooling medium, especially when using gas.

[0010] Summary of the invention

[0011] It is an object of the present invention to provide an improved receiving device for receiving a workpiece for a laser processing process, in particular for laser cladding welding.

[0012] It is particularly an object of the present invention to provide a receiving device for receiving a workpiece, with which problems and / or damage to the workpiece caused by excessive heat input, in particular excessive heat input per unit of time, into the workpiece during the laser processing process are reduced or prevented.

[0013] It is particularly an object of the present invention to provide a receiving device for receiving a workpiece, with which the workpiece can be cooled and / or with which the temperature of the workpiece can be controlled.

[0014] These and other problems apparent to a person skilled in the art from the present disclosure are solved by the subject matter of the independent claims. Advantageous further developments are the subject matter of the respective dependent claims.

[0015] According to a first aspect of the present disclosure, a holding device for receiving at least one workpiece for a laser processing process for processing the workpiece by means of a laser beam, in particular for laser cladding, is specified, wherein the holding device comprises: a support element for placing or receiving the workpiece, and at least one cooling device for actively cooling the workpiece. The support element can also be referred to simply as the "support". The support element holds or carries the workpiece. Precitec GmbH & Co. KG, Case: PR 975 WO

[0016] According to another aspect of the present disclosure, a laser processing system for carrying out a laser processing method for processing a workpiece by means of a laser beam is specified, the laser processing system comprising: a receiving device according to an aspect or embodiment of the present disclosure, and a laser processing device configured to direct the laser beam into at least one predetermined processing area for carrying out the laser processing method.

[0017] According to another aspect of the present disclosure, a laser processing system for laser cladding (i.e., additive manufacturing using a laser beam) on a workpiece is specified, the laser processing system comprising: a

[0018] Laser processing device, configured for directing the laser beam into at least one predetermined processing area on the workpiece; a feeding device, configured for feeding an application material into the processing area; and a receiving device for receiving the workpiece with a support element for placing or receiving the workpiece, wherein the support element is designed as a heat sink.

[0019] According to another aspect of the present disclosure, the use of the receiving device according to an aspect or embodiment of the present disclosure or the laser processing system according to an aspect or embodiment of the present disclosure is specified in a laser processing process, in particular in a laser cladding process.

[0020] According to another aspect of the present disclosure, a laser processing method is specified, comprising: providing a

[0021] Laser processing system according to aspects and embodiments of the present disclosure, placing a workpiece on the support element of the receiving device, and shining a laser beam into at least one predetermined processing area on the workpiece.

[0022] "Integrated in" means that a first element is arranged or formed within a second element. "Under" means that a first element is arranged under a second element, encompassing both situations where the two elements are not in direct contact and situations where the two elements are in direct contact. The same applies to "over," where "on" is synonymous with "over." Precitec GmbH & Co. KG, Case: PR 975 WO

[0023] The cooling device is designed to actively cool the workpiece. It acts as an (active) heat sink, absorbing the heat transferred to the workpiece when the laser beam is directed at it. This eliminates the need for a direct supply of a cooling medium to the workpiece. "Active cooling" means that additional and / or external energy, particularly electrical energy, is used for cooling. For example, the external energy can be used to generate or maintain a flow of a cooling medium. Furthermore, the receiving element and an optional mask of the receiving device can also serve as active and / or passive heat sinks.

[0024] The support element or mounting device is distinct from the base or table of the laser processing system on which the support element and the workpiece rest. The base or table merely serves as a support and connection to the floor and can, in particular, be permanently attached to the floor.

[0025] Aspects and embodiments of the present disclosure may include one or more of the following optional features:

[0026] The workpiece can be flat, a plate, or a sheet. It can be a metallic workpiece. The workpiece can have a thickness of 1 mm to 2 mm, including the limits.

[0027] The support element can be a flat surface and / or a plate. It can be located on a side of the workpiece facing away from the laser beam and / or the processing area. Alternatively, it can be located on the underside of the workpiece, which can also be referred to as the back. The workpiece can rest on a receiving surface of the support element, which can be essentially flat. The receiving surface can form a top surface of the support element and / or face upwards. The support element can be designed as a passive heat sink. It can be solid, specifically a solid piece of metal. This metal piece can include or consist of at least one of the following elements, or an alloy containing one or more of them: copper, aluminum, molybdenum, niobium, tantalum, tungsten, nickel.The support element can be designed as a solid block consisting of a material that includes or is graphite, a graphite modification, or carbon fiber reinforced carbon (CFC).

[0028] The holding device includes at least one cooling device for actively cooling the workpiece. The holding device can have several, in particular two, three or four, cooling devices. Precitec GmbH & Co. KG, Case: PR 975 WO

[0029] The workpiece must have cooling devices. At least one of these cooling devices can be in thermally conductive contact with the support element. At least one of the cooling devices can be integrated into the support element. For example, a first cooling device can be integrated into the support element. By integrating the first cooling device into the support element, heat can be dissipated particularly efficiently from the underside of the workpiece. This effectively prevents deformation or discoloration of the workpiece, especially on its underside.

[0030] The holding device can include at least one mask for laser processing, in particular for the application of a material. The mask can be configured to fix the workpiece to the support element. The mask can be configured for heat dissipation and / or to increase the contour accuracy of the laser processing. The mask can be arranged on the top side of the workpiece. The mask can serve as a mold for laser processing. For example, in laser cladding, the mask can be configured as a mold for applying a material and / or for structures to be formed on the workpiece from the material. The mask can surround the material to be applied to or already applied to the workpiece to achieve dimensional stability of the material or the structures. The mask can thus be used to stabilize the shape of the material or structures.The mask must be set up with structures formed from the material applied to the workpiece. It can be designed as a grid.

[0031] The mask can enclose at least one processing area and / or serve as a mask for forming structures by laser cladding. The processing area can be located on the top side of the workpiece. The mask can include at least one recess, preferably a through-hole, corresponding to the at least one processing area, e.g., for directing the laser beam into the processing area. An inner contour of the recess can partially or completely correspond to a structure to be formed in the at least one processing area by the laser processing method.

[0032] The mask can be designed as a passive heat sink. The mask can be solid. In particular, the mask can be designed as a solid piece of metal. The metal piece can include or consist of at least one of the following elements or an alloy with one or more of the following elements: copper, aluminum, molybdenum, niobium, tantalum, tungsten, nickel. The mask can be designed as a solid block consisting of a material that includes or is carbon fiber reinforced carbon (CFC). Alternatively, at least one cooling device can be integrated into the mask. For example, a second cooling device can be integrated into the mask.

[0033] The holding device can further comprise at least one heat sink. The heat sink can be flat and / or plate-shaped. The holding device can comprise several heat sinks, for example, two heat sinks. At least one of the at least one heat sink can be arranged below the support element and / or below the workpiece. At least one of the at least one heat sink can be in thermally conductive contact with the support element or thermally connected to the support element. At least one of the at least one heat sink can be arranged above or on the workpiece and / or above or on the mask. At least one of the at least one heat sink can be in thermally conductive contact with the mask or thermally connected to the mask. For example, a first heat sink can be arranged below the support element. Furthermore, a second heat sink can be arranged above the mask.At least one of the cooling devices can be integrated into the heat sink. For example, a third cooling device can be integrated into the first heat sink and a fourth cooling device into the second heat sink. The support element can be thermally connected to the first heat sink, and / or the mask can be thermally connected to the second heat sink.

[0034] The heat sink can be solid, especially a solid piece of metal. Alternatively, at least one cooling device can be integrated into the heat sink.

[0035] The support element and / or the mask and / or the at least one heat sink may be made of metal or a metal alloy, or may comprise metal or a metal alloy.

[0036] The support element and / or the mask and / or the at least one heat sink may include or consist of at least one of the following elements or an alloy with one or more of the following elements: copper, aluminum, molybdenum, niobium, tantalum, tungsten, nickel.

[0037] The mounting element and / or the mask and / or the at least one heat sink may comprise or consist of a non-metal, graphite, carbon material or ceramic material.

[0038] The material of the support element and / or the mask and / or the at least one heat sink, in particular the ceramic material, can have a thermal conductivity of 50 W / (mK) or greater, preferably 100 W / (mK) or greater, and particularly preferably 150 W / (mK) or 180 W / (mK). The material of the support element and / or the mask and / or the at least one heat sink, in particular the ceramic material, can be silicon carbide or aluminum nitride.

[0039] The receiving device may further include a thermally conductive layer. The thermally conductive layer may be arranged on the workpiece and / or the support element and / or the mask and / or the heat sink. The thermally conductive layer may be arranged between the workpiece and the support element and / or the mask. The thermally conductive layer may serve to improve heat transfer from the workpiece to the support element or the mask. The thermally conductive layer may comprise thermal paste and / or thermally conductive adhesive tape and / or a thermal pad.

[0040] The support element can be in direct contact with the workpiece. For example, the receiving surface of the support element and the underside of the workpiece and / or the side of the workpiece facing away from the laser beam can be in direct contact with each other. Alternatively, a first heat-conducting layer can be arranged between the support element and the workpiece.

[0041] The mask can be in direct contact with the workpiece. For example, a side of the mask facing away from the laser beam and / or a laser processing device can be in direct contact with a top surface of the workpiece and / or the side of the workpiece where the processing area is located and / or onto which the laser beam is directed. Alternatively, a second heat-conducting layer can be arranged between the support element and the workpiece.

[0042] At least one of the at least one heat sinks, in particular the first heat sink, can be arranged on a side of the support element and / or the workpiece that faces away from the incident laser beam and / or the processing area and / or the laser processing device. The first heat sink can be in direct contact with the support element. Alternatively, a third heat-conducting layer can be arranged between the first heat sink and the support element.

[0043] At least one of the at least one heat sinks, in particular the second heat sink, can be arranged on a side of the mask and / or the workpiece facing the incident laser beam and / or the laser processing device. The second heat sink can be in direct contact with the mask. Alternatively, a fourth thermally conductive layer can be arranged between the second heat sink and the mask. Precitec GmbH & Co. KG, Case: PR 975 WO

[0044] The advantage of using a mask or heat sink with a cooling device on the workpiece surface is that heat dissipation from the workpiece also occurs on the top surface. This significantly reduces the heat-affected zone, particularly during laser cladding. Furthermore, the mask increases the contour accuracy of the structure applied to the workpiece.

[0045] The receiving device can therefore comprise at least one thermally conductive layer, in particular one of the first to fourth thermally conductive layers. The at least one thermally conductive layer can comprise a thermally conductive compound. In particular, the at least one thermally conductive layer can comprise a thermal paste and / or a thermal pad. The thermally conductive layer can improve heat conduction between the corresponding elements in order to improve heat dissipation from the workpiece.

[0046] The cooling device can have one or more channels for guiding a cooling medium. Alternatively or additionally, the cooling device can have one or more cooling fins around which the cooling medium flows. The cooling medium can be a fluid, in particular a gas or a liquid. The cooling medium can be air, water, or gaseous or liquid nitrogen. The cooling fin(s) can be integral and / or formed in one piece with the support element and / or the mask and / or the heat sink. This means that the cooling device, in the form of the cooling fin(s), is integrated into the respective element. The channel(s) can be formed in the support element and / or in the mask and / or in the heat sink. A channel is a guide device that is sealed for the cooling medium. Accordingly, the cooling fin(s) can be considered a guide device that is open for the cooling medium.The flow of the cooling medium around the cooling fins or along an inner wall of the channels dissipates the heat from the corresponding element to cool the workpiece.

[0047] The receiving device and / or the laser processing system may further include a drive unit for generating and maintaining the flow of the cooling medium. The drive unit may be powered by an external energy source. The drive unit may comprise a pump, a compressor, or a fan. The cooling device channels and the drive unit may form part of a closed cooling medium circuit.

[0048] For example, the cooling device can include cooling fins, and the drive unit can be designed as a fan. The fan can generate an airflow directed at and around the cooling fins. This allows the cooling device to dissipate heat energy from the workpiece. Precitec GmbH & Co. KG, Case: PR 975 WO

[0049] In another example, the cooling device can include channels for a coolant, and the drive unit can be designed as a pump. The pump can be connected to the channels via lines from the receiving device, and the pump and the channels can each be part of a closed cooling circuit. This allows heat energy to be dissipated from the workpiece by means of the cooling device.

[0050] The laser processing device can be a laser processing head. The laser processing system can include a feeder for supplying a material to be processed, for example in the form of a wire, into the processing area. The laser processing head can provide a coaxial shielding gas supply.

[0051] The laser processing device and / or the holding device may include a control device configured to control the cooling device and / or the drive unit in order to regulate the temperature of the workpiece and / or the holding device, in particular the support element and / or the cooling device, i.e., to set it to a predetermined temperature value. This allows the temperature of the support element and / or the workpiece to be stabilized.

[0052] The holding device may include a clamping device. The workpiece can be attached to the support element and / or the mask by means of at least the clamping device, for example, a clamping device. For example, the workpiece can be clamped between the support element and the mask.

[0053] The laser processing method can be at least one of the following: laser welding, laser cutting, laser wire welding, laser wire cladding, laser soldering, laser hardening, or an additive manufacturing process.

[0054] The laser processing method can be an additive manufacturing process and / or laser cladding.

[0055] The laser processing method can include shining the laser beam onto the workpiece and / or shining the laser beam into at least one predefined processing area. The at least one processing area can define a region on the workpiece into which the laser beam is or is to be shone to melt material. The material can be the material of the workpiece itself. Here, the laser processing method can be laser welding or laser cutting. (Precitec GmbH & Co. KG, Case: PR 975 WO)

[0056] “Workpiece” can mean that the machining area is adjacent to the workpiece or that the machining area includes part of the workpiece.

[0057] Furthermore, the laser processing method can include feeding the material to be deposited, particularly as wire, into the defined processing area. The at least one processing area can define a region adjacent to the workpiece into which the laser beam is or is intended to be directed, melting the material to deposit. This allows structures to be formed on the workpiece. A processing area can define an extent, particularly a horizontal extent of a structure. In this case, the laser processing method can be an additive manufacturing process, in particular laser brazing, laser cladding, or laser wire cladding.

[0058] The laser processing method can be used to apply, in particular weld, structures, especially cylindrical structures, to the workpiece with a diameter of 1 mm to 5 mm and / or a height of 2 mm to 15 mm, in particular 2 mm to 10 mm or 5 mm to 15 mm and / or with a wall thickness of 1 mm to 3 mm using a laser beam.

[0059] The laser processing method can also be used to apply, in particular weld, a coating material to the workpiece using a laser beam. The coating material used and / or the workpiece can comprise or consist of one of the following materials: titanium, aluminum, a titanium-aluminum alloy, an aluminum alloy, in particular an aluminum alloy of the 5000, 6000 or 70000 series, or a titanium-aluminum alloy.

[0060] The laser processing system according to aspects and embodiments of the present disclosure is configured and can be used to perform a laser processing method. The laser processing method according to aspects and embodiments can be carried out by the laser processing system according to aspects and embodiments.

[0061] Brief description of the characters

[0062] The present disclosure is described in detail below with reference to figures. The figures depict: Precitec GmbH & Co. KG, Case: PR 975 WO

[0063] Fig. 1 shows a laser processing system with a workpiece holding device in a schematic view according to embodiments of the present disclosure;

[0064] Fig. 2a-c shows a receiving device for a workpiece in a schematic view according to embodiments of the present disclosure;

[0065] Fig. 3a-c shows a workpiece holding device in a schematic view according to embodiments of the present disclosure; and

[0066] Fig. 4a, b shows a receiving device for a workpiece in a schematic view according to embodiments of the present disclosure.

[0067] Detailed description

[0068] Unless otherwise noted, the same reference numerals are used for identical and equivalent elements in the following text. Redundant descriptions of recurring features are avoided. The various embodiments and features of the figures described below are expressly combinable and should not be understood as complete embodiments.

[0069] In the following figures, a "horizontal" direction refers to a direction in an x-y plane of a Cartesian coordinate system, and a vertical direction refers to a direction parallel to a z-axis of the Cartesian coordinate system. Terms such as "above," "over," "on," "below," "top," and "bottom" are (relative) indications of the vertical direction.

[0070] Fig. 1 shows a laser processing system with a workpiece holding device in a schematic view according to embodiments of the present disclosure.

[0071] The laser processing system 10 is configured for processing a workpiece 16 using a laser beam 18. The laser processing system 10 is configured for carrying out a laser processing method according to embodiments of the present disclosure.

[0072] The laser processing system 10 comprises a laser processing device 12, which is configured, for example, as a laser processing head. The laser processing system 10 also comprises a laser source 14. The laser source 14 generates a laser beam and directs the laser beam to the laser processing device 12 (Precitec GmbH & Co. KG, Case: PR 975 WO) via an optical fiber 15. The laser processing device 12 directs the laser beam 18 onto the workpiece 16. The laser processing device 12 includes beam guiding optics and beam shaping optics (not shown). Furthermore, the laser processing device 12 may include focusing optics for focusing the laser beam 18 onto the workpiece 16.

[0073] The laser processing system 10 is configured to direct the laser beam 18 into at least one processing area 20. In the case of laser welding or laser cutting, the processing area 20 can cut the top surface of the workpiece 16, i.e., it also extends partially into the workpiece 16. This melts the material of the workpiece 16, thereby welding or cutting the workpiece 16.

[0074] In the case of laser cladding, at least one processing area 20 can adjoin the top surface of the workpiece 16 from above; it is thus arranged adjacent to the workpiece 16. For laser cladding, the laser processing system 10 includes a feeding device 22 for feeding the cladding material 24, in particular in the form of a wire, also called welding wire, into the processing area 20. In the processing area 20, the cladding material 24 is melted by the laser beam 18, deposited onto the workpiece 16, and bonds with the workpiece 16 or the previously deposited cladding material 24. This allows structures to be formed on the workpiece 16.

[0075] To position the workpiece 16 for the laser processing process, the laser processing system 10 includes a holding device 26 for receiving the workpiece 16. The holding device 26 comprises a support element 28, for example, a plate, and a cooling device 30 for actively cooling the workpiece 16. The workpiece 16 can be attached to the support element 28. Fig. 1 and the following figures show the workpiece 16 and the support element 28 in a cross-sectional view. As shown, the cooling device 30 is integrated into the support element 28, wherein the cooling device 30 is designed as several channels in the support element 28. The channels can, for example, extend horizontally through the support element 28. However, the present invention is not limited to this.

[0076] The support element 28 is arranged below the workpiece 16. The support element 28 is located on a side of the workpiece 16 that faces away from the processing area 20 or the incident laser beam 18. This side forms the underside of the workpiece 16.

[0077] The channels serve to guide a flow of cooling medium through the support element 28. Water, for example, can be used as the cooling medium. For generating the cooling medium - Precitec GmbH & Co. KG, Case: PR 975 WO

[0078] Stroms provides a drive unit 32. The drive unit 32 is designed, for example, as a pump. The drive unit 32 can be connected to the cooling device 30 or the channels by means of supply and discharge lines 34 to form a closed coolant circuit. Other elements of the coolant circuit, such as a heat exchanger for the cooling medium, are not shown in Fig. 1.

[0079] The laser processing system can further comprise a control device 36. The control device 36 can be configured to control the laser source 14, the laser processing device 12, and the feeder 22 to perform the laser processing process. Furthermore, the control device 36 can control the drive unit 32 to, for example, regulate the pressure, flow rate, or other parameters of the cooling medium or the cooling medium flow. The laser processing system 10 can also have one or more temperature measuring devices (not shown) on the workpiece 16 and / or on the support element 28. The control device 14 can receive temperature readings from the temperature measuring device and, based on these readings, control the drive unit 32. The control device 36 can thus be configured to control the drive unit 32 to regulate the temperature of the support element 28 and / or the temperature of the workpiece 16.to set to a predetermined temperature value.

[0080] According to embodiments, workpiece 16 is a metallic workpiece and comprises, for example, aluminum or titanium or an alloy with at least one of these elements. Furthermore, workpiece 16 is designed as a plate.

[0081] Figs. 2a-c show a receiving device 26 for a workpiece in a schematic cross-sectional view according to embodiments of the present disclosure.

[0082] In Fig. 2a, the receiving device 26 comprises the support element 28, which is arranged below the workpiece 16. A (first) cooling device 30a is integrated into the support element 28. The first cooling device 30a is formed in the form of channels in the support element 28. The channels run essentially in a horizontal direction, with several connected channels forming a (continuous) channel.

[0083] In Fig. 2b, the receiving device 26 additionally includes a mask 38, which is arranged on the workpiece 16, compared to Fig. 2b. The mask 38 is also designed as a plate and includes recesses 37a-c in the form of through holes. The recesses 37a-c each surround a machining area 20a-c. The mask 38 improves heat dissipation from the workpiece 16. Precitec GmbH & Co. KG, Case: PR 975 WO

[0084] The mask 38 is arranged above the workpiece 16. In particular, the mask 38 is arranged on a side of the workpiece 16 that faces the processing area 20 or the incident laser beam 18. This side can form the top surface of the workpiece 16.

[0085] The recesses 37a-c serve to allow the laser beam 18, with the mask 38 placed on the workpiece 16, to be directed into the processing area 20a-c, and, if necessary, to allow the deposit material 24 to be introduced into the processing area 20a-c. Furthermore, the inner contour of the recesses 37a-c corresponds to a structure to be formed in the respective processing area 20a-c (see Fig. 2c). This allows the recesses 37a-c to serve as a mold for the molten deposit material 24 and to improve the shaping of the structures to be formed.

[0086] In Fig. 2c, the mask 38 additionally includes a second cooling device 30b, also in the form of channels formed in the mask 38. Furthermore, Fig. 2c shows that structures have already been formed in the recesses 20b and 20c, but not yet in the recess 20a.

[0087] In Figures 2a-c, the mask 38 and the support element 28 are in direct contact with the workpiece 16. The upper surface of the support element 28 touches the underside of the workpiece 16, and the underside of the mask 38 touches the upper surface of the workpiece 16. According to embodiments, a thermally conductive layer can be arranged between the workpiece 16 and the support element 28. The thermally conductive layer can, for example, comprise a thermal paste or at least a thermal pad.

[0088] Figs. 3a-c show a receiving device for a workpiece in a schematic cross-sectional view according to embodiments of the present disclosure.

[0089] In Figs. 3a-c, the receiving device 26 further comprises a (first) heat sink 40. The heat sink 40 is arranged below the receiving element 28. According to embodiments not shown, a second heat sink can be arranged on the mask 38.

[0090] Fig. 3a is based on Fig. 2a, i.e., the receiving device 26 comprises the support element 28, the (first) cooling device 30a, which is integrated into the support element 28, and the heat sink 40. In Fig. 3b, the receiving device 26, compared to Fig. 3a, further comprises the mask 38, into which the second cooling device 30b is integrated. In Fig. 3c, Precitec GmbH & Co. KG, Case: PR 975 WO

[0091] The receiving device 26 also includes a third cooling device 30c, which is integrated into the heat sink 40 in the form of channels.

[0092] However, the present disclosure is not limited to the fact that a cooling device must be integrated into the receiving element 28.

[0093] Figs. 4a, b show a receiving device for a workpiece in a schematic view according to further embodiments of the present disclosure.

[0094] Fig. 4a shows a receiving device 26 with a receiving element 28, the heat sink 40 and a mask 38. A cooling device is (only) integrated into the heat sink 40 in the form of the third cooling device 30c.

[0095] Fig. 4b shows a receiving device 26 with a receiving element 28 and a mask 38. A cooling device is (only) integrated in the mask 38 in the form of the second cooling device 30b.

[0096] According to embodiments, the workpiece 16 and the structures formed on it can be made of aluminum or an aluminum alloy. The support element 28 and the mask 38 can be made of copper or a copper alloy. The heat sink 40 can be made of aluminum or an aluminum alloy. When the workpiece 16 and the mask 38 are made of different materials, it is ensured that the structures applied to the workpiece 16 do not bond with the mask 38, or that contact between the mask 38 and the molten coating material 24 is prevented.

[0097] The idea underlying the invention can be described as follows, without all features and elements described below having to be part of all embodiments, because the invention is defined by the subject matter of the independent claims:

[0098] The workpiece is placed on a support (workpiece carrier) designed as a heat sink and made of a material with high thermal conductivity. This heat sink can be made of copper or aluminum, for example, but non-metallic materials with high thermal conductivity are also conceivable, such as graphite or silicon carbide. This support is actively cooled, for example, by circulating a cooling medium (e.g., water) through integrated cooling channels. Alternatively, the support can be placed on an actively cooled heat sink. Precitec GmbH & Co. KG, Case: PR 975 WO

[0099] Furthermore, it has proven particularly advantageous in weld overlay processes to equip the workpiece carrier with an additional mask that can fully or partially conform to the outer contour of the structure to be welded and, in particular, facilitates additional heat dissipation. For this reason, it is also advantageous to make this mask from a material with high thermal conductivity. This mask can also be actively cooled or thermally connected to an actively cooled heat sink. The advantage of using such a mask is that heat dissipation also occurs on the top surface of the workpiece, thereby reducing the heat-affected zone during the weld overlay process. Additionally, thermally conductive pastes or pads can be used to improve the thermal connection between the workpiece and the workpiece carrier, as well as between the workpiece and the mask.

Claims

Precitec GmbH & Co. KG, Case: PR 975 WO Claims 1. Receiving device (26) for receiving a workpiece (16) for laser processing of the workpiece (16) by means of a laser beam (18), comprising: at least one support element (28) for placing the workpiece (16); and at least one cooling device (30a-c) for actively cooling the workpiece (16).

2. Receiving device according to claim 1, further comprising at least one mask (38) for improving heat dissipation from a top surface of the workpiece (16).

3. Receiving device according to one of the preceding claims, wherein at least one of the at least one cooling device (30a-c) is integrated in the support element (28); and / or at least one of the at least one cooling device (30a-c) is integrated in the mask (38); or wherein the support element (28) and / or the mask (38) is solid and / or designed as a passive heat sink.

4. Receiving device according to one of the preceding claims, wherein the support element (28) and / or the mask (38) is made of metal or a metal alloy, and / or wherein the support element (28) and / or the mask (38) comprises a metal or a metal alloy, and / or wherein the support element (28) and / or the mask (38) comprises or consists of at least one of the following elements or an alloy with one or more of the following elements: copper, aluminum, molybdenum, niobium, tantalum, tungsten, nickel.

5. Receiving device according to one of the preceding claims, wherein the support element (28) and / or the mask (38) comprises or consists of a non-metal, graphite, a carbon material or a ceramic material, and wherein the ceramic material is silicon carbide or aluminum nitride and / or has a thermal conductivity of 50 W / (mK) or greater than 50 W / (mK), preferably 100 W / (mK), particularly preferably 150 W / (mK) or 180 W / (mK).

6. Receiving device according to one of the preceding claims, further comprising a heat sink (40) arranged under the support element (28) and in which at least one of the at least one cooling device (30a-c) is integrated. Precitec GmbH & Co. KG, Case: PR 975 WO 7. Receiving device according to one of the preceding claims, wherein a heat-conducting layer is arranged between the workpiece (16) and the support element (28) and / or between the workpiece (16) and the mask.

8. Receiving device according to one of the preceding claims, wherein the at least one cooling device (30a-c) has one or more channels for guiding a cooling medium, and / or wherein the at least one cooling device (30a-c) comprises one or more cooling fins for flowing through the cooling medium.

9. Receiving device according to claim 8, further comprising a drive unit for generating and / or maintaining a flow of the cooling medium.

10. Receiving device according to one of the preceding claims, further comprising a control device (36) which is configured to set a temperature of the workpiece (16) and / or a temperature of the support element (28) to a predetermined temperature value.

11. Laser processing system (10) for laser processing of a workpiece (16) by means of a laser beam (18), comprising: a receiving device (26) according to one of the preceding claims, and a laser processing device (12), configured to direct the laser beam (16) into at least one processing area (20a-c) on the workpiece (16).

12. Laser processing system (10) according to claim 11, which is set up for laser cladding and further comprises: a feeding device for feeding a cladding material into the processing area (20a-c).

13. Use of the receiving device according to one of claims 1-10 or of the laser processing system according to claim 11 or 12 in a laser processing method, wherein the laser processing method is at least one of the following: laser welding, laser cutting, laser wire welding, laser wire cladding, laser brazing, laser hardening, or an additive manufacturing process.

14. Use of the receiving device according to one of claims 1-10 or of the laser processing system according to claim 11 or 12 in an additive manufacturing process using a laser beam for applying, in particular welding, structures, in particular Precitec GmbH & Co. KG, Case: PR 975 WO cylindrical structures, on which the workpiece has a diameter of 1 mm to 5 mm and / or a height of 2 mm to 15 mm, in particular 2 mm to 10 mm or 5 mm to 15 mm and / or a wall thickness of 1 mm to 3 mm.

15. Use of the receiving device according to one of claims 1-10 or of the laser processing system according to claim 11 or 12 in a laser cladding method for applying a coating material to the workpiece by means of the laser beam, wherein the coating material used and / or the workpiece comprises or consists of one of the following materials: titanium, aluminum, an alloy with titanium and aluminum, an aluminum alloy, in particular an aluminum alloy of the 5000 series, the 6000 series or the 70000 series, a titanium-aluminum alloy.

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