Method and system for compensating laser cladding welding for distortion

Abstract

This invention relates to a method for laser cladding welding a functional layer (110) to a workpiece (100), particularly a brake disc, using a main laser beam (51) and a secondary laser beam (52). The method comprises the steps of: laser cladding welding a first workpiece side (120) in an initial configuration, wherein the main laser beam (51) is applied at a main initial power (P1) and the secondary laser beam (52) is applied at a secondary initial power (P2); and laser cladding welding a second workpiece side (130) opposite the first workpiece side (120) in a modified configuration, wherein the secondary laser beam (52) is applied at a secondary modified power (P2, mod) different from the secondary initial power (P2). The invention also relates to a system in which four beam nozzles are connected to each other via a production line.

Description

Technical Field

[0001] The present invention relates to a method for laser cladding welding a functional layer onto a workpiece, particularly a brake disc, using a main laser beam and a secondary laser beam, and a system for laser cladding welding a functional layer onto a workpiece in a manner that compensates for deformation. Background Technology

[0002] Laser cladding welding is used, for example, in repair, coating, and / or joining technologies. There is a distinction between conventional laser cladding welding (laser metal deposition (LMD), direct metal deposition (DMD), or direct energy deposition (DED)) and so-called high-speed laser cladding welding (HS-LMD or ultra-high-speed laser cladding welding (EHLA)). For example, the HS-LMD method is described in publications DE 102011 100 456 A and DE 10 2018 130 798 A1. Furthermore, publication DE 10 2022100 173 A1 discloses an additive manufacturing method in which a first laser beam is emitted from a nozzle unit and a second laser beam is emitted from a separate head and aligned with the workpiece to additively apply powdered building material onto the workpiece.

[0003] Laser cladding welding can be used to apply functional layers to workpieces. Compared to unprocessed workpieces, functional layers typically increase the load-bearing capacity of workpieces processed via laser cladding welding. Functional layers can serve as, for example, wear-resistant layers. The application of functional layers can be based on diffusion processes, fusion and / or melting of the workpiece surface, application of additional material, and subsequent cooling, resulting in a material-locked bond between the matrix structure containing hard material particles and the material surface. Laser cladding welding generates heat on the workpiece, which can lead to workpiece deformation. Deformation may hinder the desired increase in load-bearing capacity. Summary of the Invention

[0004] Based on existing technology, the purpose of this invention is to provide an improved laser cladding welding method and system. This invention particularly aims to minimize or completely compensate for workpiece deformation, especially thermal deformation. This invention also strives to achieve efficient workpiece processing while meeting the highest quality standards.

[0005] This objective is achieved by a method and system having the features of the independent claims. Advantageous improvements are derived from the dependent claims, the description, and the drawings.

[0006] Accordingly, a method is provided for laser cladding welding of a functional layer onto a workpiece, particularly a brake disc, using a main laser beam and a secondary laser beam. The functional layer can be a two-layer structure, consisting of a base adhesion layer and a wear-protective layer disposed thereon. The adhesion layer can be formed of a metallic material, and the wear-protective layer, in addition to the metallic material as the matrix, can contain hard material particles, such as carbides, particularly tungsten carbide and titanium carbide, especially iron-chromium as a binder. In particular, hard material particles made of titanium carbide and iron-chromium enable high-power laser cladding welding without the risk of crack formation. Therefore, particularly high tolerances can be achieved for these hard material particles with varying laser power. Alternatively, the functional layer can be a single layer consisting only of the wear-protective layer. Rotationally symmetric components, such as brake discs, hydraulic cylinders, pressure rollers, or sliding bearings, are particularly suitable as workpieces. The brake disc can have a wheel side with a hub and a hub side opposite to the wheel side. The main laser beam and / or the auxiliary laser beam can have a ring beam and a core beam to achieve a plateau-shaped intensity distribution (“flat-top”) of the laser beam, resulting in a reduced intensity in the core region compared to the edge region. The main and auxiliary laser beams can originate from the same laser source. The main and auxiliary beams can induce multiple process zones for laser cladding welding. These process zones can extend adjacent to each other to ensure a geometrically close arrangement to reduce heat loss between the two laser beams. The main laser beam can interact with powdered admixture material to create a functional layer. The auxiliary laser beam can be used for pre- or post-processing of the process locations processed by the main laser beam. The auxiliary laser beam can be positioned in front of or behind the main laser beam in the feed direction of the beam nozzle relative to the workpiece movement.

[0007] This method includes the step of laser cladding welding on a first workpiece side, particularly the wheel side of a brake disc, in an initial configuration, wherein a main laser beam is applied at a main initial power and a secondary laser beam is applied at a secondary initial power. During the processing of the first workpiece side, the main initial power and / or the secondary initial power can be constant. The main initial power can be less than the secondary initial power to induce metallurgical advantages in the bonding of the powdered admixture material to the workpiece. Alternatively, the main initial power can be equal to or greater than the secondary initial power.

[0008] The method also includes a step of laser cladding welding on a second workpiece side opposite to the first workpiece side, particularly the hub side of the brake disc, under a modified configuration, wherein, in this modified configuration, a secondary laser beam is applied with a secondary modified power different from the secondary initial power. The secondary modified power can be at least partially lower than the secondary initial power. Consequently, the molten pool induced on the second workpiece side by the modified configuration can have a lower temperature than the molten pool induced on the first workpiece side by the initial configuration, which reduces workpiece thermal deformation caused by the modified configuration, particularly because the lower molten pool temperature results in less shrinkage. The secondary modified power can also be at least partially higher than the secondary initial power. Consequently, the molten pool induced on the second workpiece side by the modified configuration can have a higher temperature than the molten pool induced on the first workpiece side by the initial configuration, which increases workpiece thermal deformation caused by the modified configuration to compensate for the corresponding workpiece deformation caused by the initial configuration. During the processing of the second workpiece side, the secondary modified power can be constant or variable. The laser cladding welding step on the second workpiece side can be performed using a different beam nozzle than the laser cladding welding step on the first workpiece side. The method disclosed herein is not limited to being performed using the same beam nozzle.

[0009] In this way, deformation-compensating laser cladding welding becomes possible. The workpiece may already be deformed before processing the first workpiece side, and this deformation will be further aggravated by laser cladding welding in the initial configuration. By performing laser cladding welding in a modified configuration, deformation generated during the process and / or deformation that existed before the process can be compensated. The present invention can utilize the characteristic that deformation increases with the power input to the workpiece without incurring a loss in the quality of the functional layer. The sub-laser beam can perform pre-processing or post-processing functions, so that its variation has no effect or only an indirect effect on the quality of the functional layer welded by the main laser beam. However, by changing the power of the sub-laser beam from the sub-initial power to the sub-corrected power, the total power input to the workpiece from the main laser beam and the sub-laser beam can be affected, especially the heat input. Heat input is likely the main cause of deformation, so the variation of the sub-laser beam power has proven to be a suitable parameter for compensating for deformation. Therefore, depending on the sub-corrected power, the shrinkage of the functional layer can be increased or decreased to adjust the deformation of the brake disc.

[0010] In one implementation, the secondary correction power is adjusted according to the deformation of the workpiece in order to suppress that deformation. The secondary correction power can influence the heat input of the secondary laser beam into the workpiece, which, along with knowledge of the component geometry, can be used to compensate for the deformation. The component geometry can be derived from empirical data.

[0011] In addition to or instead of empirical data, in one embodiment, the method may include a step of detecting the workpiece geometry, wherein the sub-correction power is adjusted based on the detected workpiece geometry. The detection can be contact-based or optical, such as using an optically oriented sensor, i.e., a line laser, or performed in a camera-based manner. Taking the detected workpiece geometry into account when adjusting the sub-correction power further helps to minimize workpiece deformation.

[0012] In one implementation, the workpiece geometry is inspected before and / or after laser cladding welding is performed on the first workpiece side in the initial configuration. When inspecting before laser cladding welding on the first workpiece side, deviations from the ideal geometry in the initial state are detected. This improves the geometric tolerance that the method can perform. When inspecting after laser cladding welding on the first workpiece side, deformation caused by the initial configuration is taken into account.

[0013] In one embodiment, the method further includes a step of detecting the workpiece temperature, wherein the secondary correction power is adjusted based on the detected temperature. For example, the temperature inside, in front of, or behind the process zone can be detected using a pyrometer to draw conclusions about the molten pool and the resulting deformation. These conclusions can be incorporated into the determination of the secondary correction power to enable precise deformation compensation in the process. In addition to a pyrometer, a temperature probe can also be used to detect the temperature.

[0014] In one implementation, the secondary correction power varies over time to compensate for nonlinear deformation. Thus, at locations on the component where significant deformation exists, a higher secondary correction power can exist than at another location on the same component at a different time point where less deformation exists. This modeling of the secondary correction power can be particularly advantageous when the component is a two-component component with non-uniform deformation characteristics. The variation in the secondary correction power can be preset or a response to a previously detected state.

[0015] In one embodiment, the workpiece is substantially rotationally symmetric, such as a brake disc, and the secondary correction power increases with increasing radial distance from the workpiece's axis of rotation. This allows for a response to deformation that increases with increasing radial distance.

[0016] In one embodiment, the main laser beam operates at the same primary initial power in both the initial and modified configurations. Thus, the interaction between the powdered admixture and the main laser beam is unaffected by the modified configuration. If the secondary modified power is lower than the secondary initial power, in this embodiment, the total laser power, consisting of the laser powers of the main and secondary beams, is lower in the modified configuration than in the initial configuration. If the secondary modified power is higher than the secondary initial power, in this embodiment, the total laser power is higher in the modified configuration than in the initial configuration. The total laser power varies even when the laser power of the main laser beam is constant.

[0017] In one embodiment, instead of keeping the main laser beam power constant, the total laser power of the main and auxiliary laser beams remains the same in both the initial and modified configurations. This ensures that the change in the main laser beam power in the modified configuration relative to the initial configuration is equal to the difference between the initial and modified auxiliary power. The difference between the initial and modified auxiliary power is directly inversely proportional to the power of the main beam in the corresponding configuration. It is important to note that in this configuration, the auxiliary laser beam can only vary by a certain value, and the main laser beam can also vary by this value without compromising weld quality.

[0018] In one embodiment, the main laser beam and the secondary laser beam originate from the same laser source, wherein the power distribution between the main and secondary laser beams can be steplessly adjusted via a motorized adjustment unit, particularly a motorized wedge beam splitter. The motorized adjustment unit is arranged in the optical path. For example, when the motorized adjustment unit extends to half the original beam, it can cause the main and secondary laser beams to each have the same power. The closer the motorized adjustment unit moves to the edge of the original beam, the greater the difference between the main and secondary beams. Stepless adjustment is particularly suitable for making fine responses to previously detected deformations.

[0019] In one embodiment, after laser cladding welding is performed on the first workpiece side in the initial configuration, the workpiece is rotated about a transverse axis extending orthogonally to the workpiece rotation axis to perform laser cladding welding on the second workpiece side in a modified configuration. Rotation about the transverse axis can be performed using a rotation module. Thus, if the first and second workpiece sides are processed by the same beam nozzle, it is not necessary to move the beam nozzle to opposite sides. If the first and second workpiece sides are processed by different beam nozzles, rotation about the transverse axis allows the beam nozzles to be aligned with each other.

[0020] In one embodiment, a first adhesion layer is applied by laser cladding welding a first workpiece side in an initial configuration, and a second adhesion layer is applied by laser cladding welding a second workpiece side in a modified configuration. The first and / or second adhesion layers may be uniformly composed of a metallic material.

[0021] In one embodiment, the method may further include a step of laser cladding welding on a first workpiece side under a wear configuration, wherein, under this wear configuration, a main laser beam operates at a main wear power and a secondary laser beam operates at a secondary wear power to apply a first wear protection layer onto a first adhesion layer. In addition to the metallic material as a matrix, the first wear protection layer may also contain hard material particles, such as carbides, particularly tungsten carbide and titanium carbide, especially with iron-chromium as a binder. In particular, hard material particles made of titanium carbide and iron-chromium enable high-power laser cladding welding without the risk of crack formation. In one embodiment, the main wear power may be the same as the main initial power. In another embodiment, the main wear power may differ from the main initial power if, for example, detected geometry and / or detected temperature indicate a need for it. In one embodiment, the secondary wear power may be equal to the secondary initial power, or, in another embodiment, the secondary wear power may differ from the secondary initial power if, for example, detected geometry and / or detected temperature indicate a need for it.

[0022] In one embodiment, the method may further include a step of laser cladding welding on the second workpiece side under a modified wear configuration, wherein, under this modified wear configuration, the secondary laser beam operates at a secondary wear-correcting power to apply a second wear-protective layer onto the second adhesion layer. The second wear-protective layer may correspond to the configuration of the first wear-protective layer. In one embodiment, the secondary wear-correcting power may be equal to the secondary correction power. In an alternative embodiment, the secondary wear-correcting power may also differ from the secondary correction power. This further facilitates achieving deformation-free laser cladding welding.

[0023] This disclosure also relates to a system for laser cladding and welding a functional layer onto a workpiece in a deformation-compensating manner. The workpiece and the functional layer can be designed corresponding to the workpiece and functional layer in this method.

[0024] The system has a first beam nozzle designed and configured to process a first workpiece side using a main laser beam with a primary initial power and a secondary laser beam with a secondary initial power to apply a first adhesion layer. This adhesion layer can be formed of a metallic material. The primary initial power of the first beam nozzle can be less than the secondary initial power to provide metallurgical advantages in bonding the powdered admixture to the workpiece. Alternatively, the primary initial power can be equal to or greater than the secondary initial power. The primary and / or secondary laser beams of the first beam nozzle can have an annular beam and a core beam to achieve a plateau-shaped intensity distribution of the laser beam, resulting in a reduced intensity in the core region compared to the edge region. The primary laser beam can interact with the powdered admixture to create a functional layer. The secondary laser beam can be used for pre- or post-processing of the process position processed by the primary laser beam. The secondary laser beam can be positioned in front of or behind the primary laser beam in the feed direction of the beam nozzle relative to the workpiece movement.

[0025] The system also includes a second beam nozzle designed and configured to process a second workpiece side opposite the first workpiece side using a main laser beam and a secondary laser beam having a secondary modified power different from the secondary initial power, in order to apply a second adhesion layer. The second beam nozzle and the second adhesion layer can be designed corresponding to the first beam nozzle and the first adhesion layer. The power of the main laser beam of the second beam nozzle can be equal to the main initial power of the first beam nozzle. The power of the main laser beam of the second beam nozzle can also vary relative to the main initial power. The secondary modified power can be at least partially lower than the secondary initial power. Thus, the molten pool caused by the modified configuration on the second workpiece side can have a lower temperature than the molten pool caused by the initial configuration on the first workpiece side, which reduces workpiece thermal deformation caused by the modified configuration, particularly because the lower molten pool temperature results in less shrinkage. The secondary modified power can also be at least partially higher than the secondary initial power. Thus, the molten pool caused by the modified configuration on the second workpiece side can have a higher temperature than the molten pool caused by the initial configuration on the first workpiece side, which increases workpiece thermal deformation caused by the modified configuration to compensate for the corresponding workpiece deformation caused by the initial configuration. During the machining of the second workpiece side, the secondary correction power can be constant or variable.

[0026] The system also features a third beam nozzle designed and configured to process the first workpiece side using a main laser beam and a secondary wear power different from the secondary correction power, in order to apply a first wear-protective layer. In addition to the metallic material as the matrix, the first wear-protective layer may also contain hard material particles, such as carbides, particularly tungsten carbide and titanium carbide, especially with iron-chromium as a binder. Specifically, hard material particles made of titanium carbide and iron-chromium enable high-power laser cladding welding without the risk of crack formation. The third beam nozzle can be designed corresponding to the first beam nozzle. The secondary wear power can correspond to the secondary initial power. The power of the main laser beam of the third beam nozzle can be the same as or different from the main initial power.

[0027] The system also includes a fourth beam nozzle, designed and configured to process the second workpiece side using a main laser beam and a secondary laser beam with a secondary wear correction power different from the secondary wear power, in order to apply a second wear protection layer. The second wear protection layer may correspond to the first wear protection layer. The fourth beam nozzle may be designed to correspond to the first beam nozzle. The secondary wear correction power may correspond to the secondary correction power. The power of the main laser beam of the fourth beam nozzle may be the same as or different from the main initial power.

[0028] The system's four beam nozzles are interconnected via a production line, specifically directly connected to each other, to enable deformation-compensating laser cladding welding without relying on manual operator interaction. The production line can be a conveyor belt mechanism connecting the four beam nozzles. The conveyor belt mechanism may have rotating modules between the respective beam nozzles, designed and configured to rotate the workpiece along a transverse axis between the respective beam nozzles. The conveyor belt mechanism may also have a geometry detector designed and configured to detect workpiece deformation, wherein the secondary correction power and / or secondary wear correction power are adjusted based on the detected deformation. The geometry detector can be a contact sensor, an optical sensor, or a camera. The conveyor belt mechanism may also have a temperature detector designed and configured to detect the workpiece temperature, wherein the secondary correction power and / or secondary wear correction power are adjusted based on the detected temperature. The temperature detector can be a pyrometer or a temperature probe.

[0029] The system enables laser cladding welding with compensation for deformation. Laser cladding welding using secondary correction power via a second beam nozzle and laser cladding welding using secondary wear correction power via a fourth beam nozzle can compensate for deformation generated during the process and / or deformation that existed prior to the process. In particular, based on the production line, no manual intervention by operators is required.

[0030] Brief description of the attached figures Preferred embodiments of the invention will be explained in more detail below with reference to the accompanying drawings. Wherein: Figure 1 A schematic view of the laser beam nozzle during laser cladding welding is shown; Figure 2 A system having a first beam nozzle and a second beam nozzle is shown, which process the workpiece from different sides; Figure 3 This shows the relationship between laser power on the horizontal axis and functional layer quality on the vertical axis; Figure 4 The diagram illustrates the deformation of the brake disc after the coating is applied to each side; and Figure 5 The system shown has four beam nozzles and one production line. Detailed Implementation

[0031] The embodiments are described below with reference to the accompanying drawings. Here, the same, similar, or functionally equivalent elements in different drawings are given the same reference numerals.

[0032] Figure 1 A beam nozzle 1 for laser cladding welding along a feed direction 2 is shown. Feed direction 2 is the direction of movement of the beam nozzle 1 relative to the workpiece 100. This direction can be generated by the movement of the workpiece 100, particularly rotational movement, by the movement of the beam nozzle 1, or by the superposition of the movements of the workpiece 100 and the beam nozzle 1. The feed direction 2 and the associated feed motion can be constant throughout the process. Alternatively, the feed direction and the associated feed motion can vary with the corresponding process stage. The workpiece 100 can be a rotationally symmetric workpiece, such as a brake disc, hydraulic cylinder, pressure roller, or sliding bearing. A functional layer 110 is applied to the workpiece 100 by means of laser cladding welding. The workpiece 100 has a first workpiece side 120, such as a wheel side, and a second workpiece side 130, such as a hub side.

[0033] The main laser beam 51 and the secondary laser beam 52 are emitted from the optical channel. Therefore, the beam nozzle 1 is a bifocal nozzle. The nozzle orifice 3 of the beam nozzle 1 includes a powder unit 4, which may, for example, have multiple ejector guides, each capable of housing a powder ejector. Alternatively, the powder unit 4 may have a powder annular gap channel. Powdered admixture 140 is directed onto the workpiece 100 via the powder unit 4. The laser beams 51 and 52 heat the workpiece 100, forming a molten pool 150 on the material surface. Furthermore, the laser beams 51 and 52 heat the powdered admixture 140, which is particularly composed of hard material particles, such as carbides and matrix materials. For this purpose, the laser beams 51 and 52 may have reduced core strength. Once the molten pool 150 cools, a weld-coated functional layer 110 is formed, which may, for example, include an adhesion layer and a wear-resistant layer. The weld-coated functional layer 110 strengthens the material surface and improves its load-bearing capacity. The beam nozzle 1 can also be adapted to guide process protection gas 160 in the radial outer section to shield the process zone and prevent oxidation.

[0034] Figure 2 a and Figure 2 Figure b shows a beam nozzle 1 that moves relative to the workpiece surface along the feed direction 2 to form a functional layer 110 on the workpiece 100. The beam nozzle 1 processes the workpiece 100 using a main laser beam 51 and a secondary laser beam 52. The workpiece 100 may be a brake disc. The brake disc has a rotation axis 170 corresponding to the rotation axis of the brake disc. The rotation axis 170 is orthogonal to the transverse plane. A transverse axis 180 extends in the transverse plane. Between processing on the first workpiece side 120 and processing on the second workpiece side 130, the workpiece 100 may be rotated about the transverse axis 180. Thus, the respective beam nozzles performing processing have the same orientation when processing the first workpiece side 120 and the second workpiece side 130. Alternatively, the workpiece 100 may not rotate between processing on the first workpiece side 120 and processing on the second workpiece side 130; instead, the beam nozzle performing processing may be moved to the other workpiece side.

[0035] Figure 2 A illustrates the steps of laser cladding welding on the first workpiece side 120 in an initial configuration. In the initial configuration, the main laser beam 51 is applied with a main initial power P1, and the secondary laser beam 52 is applied with a secondary initial power P2. The initial configuration is selected to ensure the corresponding quality of the functional layer 110. The main initial power P1 and / or the secondary initial power P2 can be constant during the processing of the first workpiece side 120. The main initial power P1 can be less than the secondary initial power P2 to cause metallurgical advantages in the bonding between the powdered additive material 140 and the workpiece 100. Alternatively, the main initial power P1 can be equal to or greater than the secondary initial power P2.

[0036] Figure 2 b illustrates the steps of laser cladding welding on the second workpiece side 130 under a modified configuration. In the modified configuration, the secondary laser beam 52 is applied with a secondary modified power P2,mod, different from the secondary initial power P2. The secondary modified power P2,mod can be at least partially lower than the secondary initial power P2. Consequently, the molten pool 150 induced on the second workpiece side 130 by the modified configuration can have a lower temperature than the molten pool previously induced on the first workpiece side 120 by the initial configuration, which reduces the thermal deformation of the workpiece 100 caused by the modified configuration, particularly because the lower molten pool temperature results in less shrinkage. The secondary modified power P2,mod can also be at least partially higher than the secondary initial power P2. Consequently, the molten pool 150 induced on the second workpiece side 130 by the modified configuration can have a higher temperature than the molten pool induced on the first workpiece side 120 by the initial configuration, which increases the thermal deformation of the workpiece 100 caused by the modified configuration to compensate for the corresponding deformation of the workpiece 100 caused by the initial configuration. During the machining of the second workpiece side 130, the secondary correction power P2,mod can be constant or variable. Figure 2 The beam nozzles in a and 2b can be the same component or different beam nozzles.

[0037] Figure 3 Two graphs are shown, illustrating the different process windows depending on the type of beam nozzle used. The total laser power P, i.e., the sum of the laser powers of the main laser beam 51 and the secondary laser beam 52, is plotted on the horizontal axis. The quality Q of functional layer 110 is plotted on the vertical axis. At the threshold Q... This ensures that the functional layer 110 has a sufficiently high quality. Figure 3 a shows the power spectrum ΔP1, within which conventional beam nozzles, i.e., single-focal nozzles that guide a single laser beam, ensure that the functional layer has sufficiently high quality. Figure 3 b shows the power spectrum ΔP2, within which the bifocal nozzles guiding the main laser beam 51 and the secondary laser beam 52 ensure a sufficiently high quality for the functional layer. Power spectrum ΔP2 is significantly larger than power spectrum ΔP1. This invention utilizes this relationship, namely, varying the total laser power P according to the corresponding process stage and the respective workpiece side being processed, in order to compensate for deformation on the one hand, and on the other hand, not fall below the functional layer quality threshold Q. .

[0038] Figure 4 The machining of the brake disc is illustrated schematically. The left column shows the brake disc in its initial state before laser cladding welding. Figure 4In the first embodiment, the brake disc is not deformed in its initial state. In another embodiment, not shown, the brake disc is deformed in its initial state. The middle section shows the brake disc after laser cladding welding of the first workpiece side 120 in its initial configuration. Figure 4 a and Figure 4 In step b, the initial power P1 of the main laser beam 51 and the initial power P2 of the secondary laser beam 52 are applied to the first workpiece side 120, causing uniform deformation. Figure 4 In c, the underlying brake disc is a dual-component brake disc, which, for example, has a hub made of aluminum and friction surfaces made of cast iron. This composition leads to nonlinear deformation, such as... Figure 4 As shown in the middle of c. The dashed lines indicate the brake disc in its undeformed state to illustrate the deformation caused by laser cladding welding. The deformation shown is highly simplified and not presented to scale. The primary initial power P1 and the secondary initial power P2 can each be constant during processing on the first workpiece side 120. The values ​​of the corresponding powers P1 and P2 can be variably adjusted. The primary initial power P1 can be less than the secondary initial power P2 to provide metallurgical advantages in the bonding between the powdered additive material 140 and the workpiece 100. Alternatively, the primary initial power P1 can be equal to or greater than the secondary initial power P2.

[0039] The right column shows the brake disc after laser cladding welding on the second workpiece side 130. Figure 4 In step a, the configuration used for machining the second workpiece side 130 corresponds to the initial configuration. Accordingly, in Figure 4 In the case shown in diagram a, the brake disc deforms after laser cladding welding is performed on the second workpiece side. According to this disclosure, this can be remedied by applying a modified configuration to the second workpiece side 130, such as... Figure 4 As shown in b. Because the secondary correction power P2,mod deviates from the secondary initial power P2, it allows for targeted influence on deformation. After laser cladding welding on the second workpiece side 130, the brake disc correspondingly exhibits no deformation or almost no deformation. To suppress... Figure 4 The nonlinear deformation of the dual-component brake disc in c, in Figure 4 In case c, the secondary correction power P2,mod is modulated. The secondary correction power P2,mod in the radially inner region where the brake disc deformation is smaller is lower than the secondary correction power in the radially outer region where the brake disc deformation is larger. Therefore, the nonlinear deformation of the workpiece 100 can be responded to by the modulated secondary correction power, so as to finally obtain a component that is at least approximately deformation-free, such as… Figure 4 c is shown in the right column.

[0040] Figure 5A system with a first beam nozzle 1100, a second beam nozzle 1200, a third beam nozzle 1300, and a fourth beam nozzle 1400 is shown, these beam nozzles being connected to each other via a production line 1500. The four beam nozzles 1100-1400 can be designed to be structurally identical to each other. The first beam nozzle 1100 can process a first workpiece side 120 in an initial configuration, for example, with the first workpiece side 120 facing upwards, in order to apply a first adhesion layer to the first workpiece side 120. Between the first beam nozzle 1100 and the second beam nozzle 1200, the workpiece 100 can be rotated 180° about a transverse axis 180, such that, for example, the second workpiece side 130 faces upwards; thereafter, the second beam nozzle 1200 processes the second workpiece side 130 with a secondary correction power different from the secondary initial power, in order to apply a second adhesion layer. Since the second beam nozzle 1200 processes the workpiece 100 with the secondary correction power, the deformation caused by the first beam nozzle 1100 can be compensated for. Between the second beam nozzle 1200 and the third beam nozzle 1300, the workpiece 100 can be rotated 180° again about the transverse axis, so that, for example, the first workpiece side 120 is facing upwards again. Now, the third beam nozzle 1300 can apply the first wear protection layer to the first workpiece side 120 with the first adhesion layer at a secondary wear power different from the secondary correction power. After the third beam nozzle 1300, the workpiece 100 can be rotated 180° again about the transverse axis 180, so that, for example, the second workpiece side 130 is facing upwards again. In this way, the second wear protection layer can be applied to the second workpiece side 130 with the second adhesion layer at a secondary wear correction power different from the secondary wear power. Since the fourth beam nozzle 1400 processes the workpiece 100 at the secondary wear correction power, the deformation caused by the third beam nozzle 1300 can be compensated again. Therefore, the part 100 leaves the production line 1500 in a double-layered and deformation-free manner.

[0041] Production line 1500 may be a conveyor belt mechanism. The conveyor belt mechanism may have a rotating module between the respective beam nozzles 1100-1400, designed and configured to rotate the workpiece along a transverse axis 180 between the respective beam nozzles 1100-1400. The conveyor belt mechanism may also have a geometry detector designed and configured to detect deformation of the workpiece 100, wherein the secondary correction power and / or secondary wear correction power are adjusted based on the detected deformation. The geometry detector may be a contact sensor, an optical sensor, or a camera. The conveyor belt mechanism may also have a temperature detector designed and configured to detect the temperature of the workpiece 100, wherein the secondary correction power and / or secondary wear correction power are adjusted based on the detected temperature. The temperature detector may be a pyrometer or a temperature probe.

[0042] Where applicable, all individual features shown in the embodiments may be combined and / or interchanged with each other without departing from the scope of the invention.

[0043] List of reference numerals

Claims

1. A method for laser cladding welding a functional layer (110) to a workpiece (100), particularly a brake disc, using a main laser beam (51) and a secondary laser beam (52), the method comprising the steps of: - Laser cladding welding is performed on the first workpiece side (120) under an initial configuration, in which the main laser beam (51) is applied with a main initial power (P1) and the secondary laser beam (52) is applied with a secondary initial power (P2); - Laser cladding welding is performed on the second workpiece side (130) opposite to the first workpiece side (120) in a modified configuration, wherein the secondary laser beam (52) is applied with a secondary modified power (P2,mod) that is different from the secondary initial power (P2).

2. The method according to claim 1, wherein The secondary correction power (P2,mod) is adjusted according to the deformation of the workpiece (100) in order to suppress the deformation.

3. The method according to any one of the preceding claims further includes the step of: Detecting the geometry of the workpiece, wherein, The secondary correction power (P2,mod) is adjusted based on the detected workpiece geometry.

4. The method according to claim 3, wherein The detection of the workpiece geometry is performed before and / or after the laser cladding welding performed on the first workpiece side (120) under the initial configuration.

5. The method according to any one of the preceding claims further includes the step of: The temperature of the workpiece is detected, wherein, The secondary correction power (P2,mod) is adjusted based on the detected temperature.

6. The method according to any one of the preceding claims, wherein, The secondary correction power (P2,mod) changes over time to compensate for nonlinear deformation.

7. The method of claim 6, wherein The workpiece (100) is substantially rotationally symmetric, and the secondary correction power (P2,mod) increases with the radial distance from the axis of rotation of the workpiece (100).

8. The method according to any one of the preceding claims, wherein, The main laser beam (51) operates at the same main initial power (P1) in both the initial configuration and the modified configuration.

9. The method according to any one of claims 1 to 7, wherein, The total laser power of the main laser beam (51) and the secondary laser beam (52) remains the same under the initial configuration and the modified configuration, such that the change in power of the main laser beam (51) under the modified configuration relative to the initial configuration is equal to the difference between the secondary initial power (P2) and the secondary modified power (P2,mod).

10. The method according to any one of the preceding claims, wherein, The main laser beam (51) and the secondary laser beam (52) originate from the same laser source, wherein the power distribution between the main laser beam (51) and the secondary laser beam (52) can be steplessly adjusted via a motorized adjustment unit, particularly a motorized wedge beam splitter.

11. The method according to any one of the preceding claims, wherein, After the laser cladding welding is performed on the first workpiece side (120) under the initial configuration, the workpiece (100) is rotated about a transverse axis (180) extending orthogonally to the rotation axis (170) of the workpiece (100) so as to perform laser cladding welding on the second workpiece side (130) under the modified configuration.

12. The method according to any one of the preceding claims, wherein, The first adhesion layer is applied by laser cladding welding performed on the first workpiece side (120) under the initial configuration; and The second adhesion layer is applied by laser cladding welding performed on the second workpiece side (130) under the modified configuration; It also includes the following steps: - Laser cladding welding is performed on the first workpiece side (120) under wear configuration, wherein the main laser beam (51) operates at the main wear power and the secondary laser beam (52) operates at the secondary wear power to apply a first wear protection layer on the first adhesion layer; - Laser cladding welding is performed on the second workpiece side (130) under a modified wear configuration, wherein the sub-laser beam (52) operates at a sub-wear-corrected power to apply a second wear protection layer on the second adhesion layer.

13. A system for laser cladding welding a functional layer (110) onto a workpiece (100) in a deformation-compensating manner, comprising: - A first beam nozzle (1100) is designed and configured to process a first workpiece side (120) by means of a main laser beam having a main initial power (P1) and a secondary laser beam having a secondary initial power (P2) in order to apply a first adhesion layer; - A second beam nozzle (1200) is designed and configured to process a second workpiece side (130) opposite to the first workpiece side (120) by means of a main laser beam and a secondary laser beam having a secondary modified power different from the secondary initial power (P2) in order to apply a second adhesion layer. - A third beam nozzle (1300) is designed and configured to process the first workpiece side (120) by means of a main laser beam and a secondary wear power having a power different from the secondary correction power, so as to apply a first wear protection layer; - A fourth beam nozzle (1400) is designed and configured to process the second workpiece side (130) by means of a main laser beam and a secondary laser beam having a secondary wear correction power different from the secondary wear power, so as to apply a second wear protection layer; in, The four beam nozzles (1100, 1200, 1300, 1400) are connected to each other via a production line (1500) to enable laser cladding welding that compensates for deformation.

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