Method and apparatus for producing a weld on a workpiece

Abstract

The invention relates to a method for producing a weld (10) on a workpiece (20) by means of a high-energy process beam (30), comprising the following steps: producing (S1) a weld (10) on a workpiece (20) by means of a process beam (30); scanning (S2) the weld (10) by means of a sampling beam (40); determining (S3) at least one reprocessing location (50) at which the weld penetration is below a target weld penetration and / or at which the pore size exceeds a target pore size and / or at which the porosity exceeds a target porosity; reprocessing (S4) the weld (10) at least at one reprocessing location (50) by means of the process beam (30). The invention also comprises a processing device.

Description

Technical Field

[0001] This invention relates to a method and apparatus for generating welds on a workpiece using a high-energy processing beam. Background Technology

[0002] Known methods for producing welds on workpieces include weld penetration control. Weld penetration control specifies the nominal power of the processing beam based on the current weld penetration and the desired weld penetration. The measured weld penetration is determined by measurement points (specifically OCT measurement points).

[0003] To ensure sufficient weld quality, the weld penetration control calculation steps must be performed at a sufficient speed. Only in this way can the performance of the processing beam be adjusted at a sufficient speed to minimize the weld locations where the measured weld penetration does not correspond to the desired weld penetration.

[0004] To achieve this, weld penetration control must be performed on high-performance computing units. Due to their size, these computing units cannot be integrated into the machining apparatus. Furthermore, the input and output data for weld penetration control must be transferred between the machining apparatus and the computing unit in a technically complex manner.

[0005] Even if the computing unit uses a high-performance and therefore expensive graphics board to achieve weld penetration control as quickly as possible, a sufficient number of measurement points (approximately 300) must first be established to calculate the nominal power of the machining beam to determine the current weld penetration. This results in a time delay between adjusting the nominal power of the machining beam and utilizing the machining beam to generate a weld on the workpiece, leading to insufficient weld quality or slow processing speed of the machining device. Summary of the Invention

[0006] Based on existing technology, the purpose of this invention is to achieve improved welds on workpieces.

[0007] According to the invention, this objective is achieved by the method and processing apparatus as defined in the independent or dependent claims and as described herein. Further embodiments can be found in the dependent claims.

[0008] This article describes a method for generating a weld on a workpiece using a high-energy processing beam according to the present invention. The method includes the following steps: generating a weld on the workpiece using a processing beam; scanning the weld using a sampling beam of an optical coherence tomography (OCT); determining at least one reprocessing location, at which the weld penetration is lower than a target weld penetration and / or pore size, and the target pore size and / or porosity exceeds a target porosity; and reprocessing the weld at at least one reprocessing location, particularly at the determined at least one reprocessing location, using the processing beam.

[0009] High quality can be achieved by using the method according to the invention. Even if equipment for determining online weld penetration is available, welding results that might not be achievable by determining online weld penetration alone can be achieved by subsequently identifying the locations requiring rework and precisely reworking those locations. In particular, this takes into account the fact that even if online weld penetration is determined, future readings that could affect the quality of the determination are not available. However, separating the identification of welding and weld penetration in time allows these readings to be considered and used, for example, for notification and fitting. Furthermore, this prevents over-control, especially during the setting time of weld penetration.

[0010] In principle, computationally intensive weld penetration control is also unnecessary. Therefore, expensive computing units, which potentially require expensive graphics boards, will no longer be needed. Furthermore, the data used for calculating weld penetration control no longer needs to be transmitted in real-time from the machining unit to the computing unit and vice versa. Therefore, complex and computationally intensive online calculations for weld penetration control are no longer absolutely necessary.

[0011] By using the method according to the invention, it is more likely to determine the reprocessing location directly and / or offline on the evaluation unit, which can be integrated into the processing apparatus. As a result, production costs incurred when producing welds can be significantly reduced while maintaining sufficient and / or consistent weld quality.

[0012] A workpiece may include at least two parts that are to be welded to each other. A weld can connect the parts of the workpiece to each other.

[0013] A high-energy processing beam can be a laser beam. The laser beam can be pulsed and / or exhibit continuous properties. The high-energy processing beam is aimed at one or more workpieces to perform a machining process, particularly laser beam welding. A processing zone is formed at the area where the high-energy processing beam is incident on the workpiece, and the material of the workpiece in the processing zone melts. As a result, a so-called keyhole may be formed. The keyhole is located within the molten pool and is formed by a vapor chamber generated by the interaction between the processing beam and the workpiece. The processing beam can be generated by a processing apparatus. In particular, the processing beam can be generated by a processing beam source. The processing beam source can be located on and / or in the processing apparatus and / or spaced apart from the processing apparatus.

[0014] Specifically, the sampling beam used for optical tomography measurements can be generated by an optical coherence tomography (OCT) system. Specifically, the sampling beam can be aimed at the workpiece to measure the weld. Specifically, the sampling beam can be used to determine the weld penetration, number of pores and / or pore size, and / or to determine these parameters at defined locations within the weld.

[0015] A well-tested setup provides for coupling a sampling beam into a machining beam and guiding the sampling and machining beams substantially coaxially onto the workpiece via a combined optics device. In this configuration, a sampling device (particularly a sampling scanner) can be used, for example, in the form of an adjustable mirror arrangement, by which the sampling beam can be shifted in two spatial directions in an aiming manner.

[0016] For example, a sampling scanner may have at least one (especially two) movable mirrors by means of which the sampling beam can be shifted in an aiming manner. The sampling scanner may be an acousto-optic modulator (AOM) through which the sampling beam can be shifted. The sampling device may be positioned particularly adjacent to the machining apparatus. A machining scanner that enables the machining beam to be shifted relative to the workpiece may also be provided within the machining apparatus. The machining scanner may allow the machining position on the workpiece to be shifted in at least one or two spatial directions. In some embodiments, the shift may be achieved alternatively or additionally by using the movement of a robot and / or linear axes. The machining apparatus may be particularly equipped with fixed machining optics, especially in the absence of a scanner, and the machining beam may be movable solely by, for example, mechanical shifting of the machining head.

[0017] For example, the processing scanner may have at least one (especially two) movable mirrors by means of which the processing beam can be shifted in an aiming manner. The processing scanner may be an acousto-optic modulator (AOM) through which the processing beam can be shifted in an aiming manner.

[0018] The sampling beam can be coupled to the processing scanner via a sampling scanner, and can be moved along the workpiece in one or two spatial directions by using the sampling scanner and the processing scanner. Furthermore, the sampling device can include an optical coherence tomography (OCT) imager, which can be used to perform measurements based on optical coherence tomography (OCT).

[0019] The weld penetration depth can vary at different locations within the weld. For example, the weld penetration depth can differ at different locations because the composition of the keyhole generated by the processing laser beam during weld formation can vary. Furthermore, the weld penetration depth may vary when using processing beams with different properties and when using workpieces made of different materials. For example, in the case of laser welding via pulsed laser beams and / or continuous laser beams, the weld penetration depth can be measured. Once the processing laser beam enters the workpiece, the weld penetration depth can be measured using a sampling beam. Similarly, the duration / local length of the weld or pulse can be measured, or the number of welds / pulses can be counted.

[0020] Porosity in welds can be caused by the formation of air bubbles that remain in the weld zone. Porosity can occur both internally and on the surface. Porosity can be defined by pore diameter. Porosity can be defined by the number and / or size of pores in the weld and / or a portion of the weld.

[0021] The rework location can be a point in the weld that does not meet weld quality requirements. Specifically, the rework location can be defined where the weld penetration is lower than the target weld penetration. The target weld penetration can be a predetermined value for the entire weld and / or the value distribution of the weld. Alternatively and / or additionally, for example according to DIN EN ISO 5817, the rework location can be defined where the weld porosity exceeds the target porosity. Furthermore, the rework location can alternatively and / or additionally be located where the weld porosity exceeds the target porosity, for example according to DIN EN ISO 5817.

[0022] For efficient processing, weld reprocessing can be selectively (especially specifically) performed at the reprocessing location and / or at multiple reprocessing locations.

[0023] The processing beam can be generated specifically by the processing equipment, and the sampling beam can be generated by the sampling equipment; both the processing equipment and the sampling equipment are components of the processing apparatus. For example, the processing equipment and the sampling equipment can be located within and / or integrated into the processing apparatus. Furthermore, the reprocessing location can be determined in an evaluation device, which is part of and / or integrated into the processing apparatus. Therefore, the processing apparatus can directly calculate the welding process offline.

[0024] Welds can be scanned simultaneously with weld formation. If the weld is scanned while it is being formed, the scan can be performed behind and / or on the keyhole. Therefore, direct insight into newly formed welds on and / or behind the keyhole can be obtained. Furthermore, scanning the weld while it is being formed allows for faster workpiece machining.

[0025] Alternatively and / or additionally, the determination of the rework location can be performed simultaneously with the weld scanning. This saves time in determining the rework location. Alternatively and / or additionally, the determination of the rework location can be performed after the weld scanning. In this case, all measurement points already exist when determining the rework location. Therefore, the rework location can be determined more accurately.

[0026] Furthermore, rework locations can be determined based on a single measurement point identified during weld scanning by a sampling beam. For example, rework locations can be generated at each measurement point where the weld penetration is below the target weld penetration and / or the pore size and / or porosity exceeds the target pore size and / or target porosity. This ensures high weld quality. In this case, rework locations can be determined based on a single measurement point.

[0027] In some embodiments, the weld penetration depth in the keyhole can be measured during processing, and additional measurements for determining pore size and / or porosity can be performed after processing. Thus, information about weld penetration depth and porosity can be received efficiently. In this case, the weld penetration depth is conveniently measured during the welding process because the measurement in the keyhole can be performed during the welding process. Additional measurements may require different sampling rates and / or may be difficult to perform with sufficient quality during welding. Additional sampling runs as described can be used to receive further information, such as information about porosity.

[0028] To compensate for potential measurement errors and / or inaccuracies and / or ensure that measurement errors and / or inaccuracies are not too severe when determining the rework location, the rework location can also be determined based on multiple measurement points received during weld scanning using a sampling beam. The rework location can be determined, for example, by averaging weld penetration, pore size, and / or porosity, which have already been determined based on multiple measurement points.

[0029] The method may further include at least one of the following steps: determining the nature of the weld at the rework location; determining, at the rework location, the relationship between the nature of the weld at the rework location, the desired nature of the weld, and the laser properties used to generate the processing beam that produces the weld at the rework location; and adjusting the laser properties according to said relationship, particularly at the rework location. Determining the relationship at the rework location and adjusting the laser properties can occur, particularly before and / or after determining at least one rework location, the rework of the weld.

[0030] Therefore, more precise reprocessing can be performed on the reprocessing location. Specifically, when the weld is reprocessed at at least one reprocessing location, the desired properties of the weld at that location can be achieved. The properties of the reprocessing location can be weld penetration, porosity, and / or porosity size. The desired properties of the weld can be the target weld penetration, target porosity, and / or target porosity size, and / or the target weld penetration, target porosity, and / or target porosity size for a specific section of the weld. Laser performance can be predetermined by an analog voltage (particularly a 0 to 10 volt signal). The analog voltage can be the input value of the processing equipment and / or the processing beam source. A linear relationship can exist between the two. The appropriate laser performance for reprocessing the reprocessing location can be determined by multiplying the laser performance that produces the weld by a factor. This factor can be determined by dividing the weld penetration at the reprocessing location by the target weld penetration.

[0031] To ensure high weld quality using a simple method, the method may further include redefining at least one rework location where the weld penetration is lower than the target weld penetration and / or where the porosity exceeds the target porosity and / or where the porosity exceeds the target porosity. Redefining the properties of the rework location can be performed after reworking the weld at that location. For example, the method steps of determining the relationship between the weld properties at the rework location, the desired weld properties, and the laser properties used to generate the processing beam that produces the weld at the rework location, adjusting the laser properties according to said relationship, and reworking the weld at at least one rework location can be performed iteratively until it can be determined in the method step of redefining at least one rework location that there are no more rework locations. Therefore, sufficient weld quality can be ensured with low computational power.

[0032] The method may also include at least one of the following steps: generating a calibration weld by a processing beam; determining the properties of the calibration weld by a sampling beam. Therefore, generating the calibration weld and determining its properties are performed before generating the actual weld. Due to the properties of the calibration weld, the settings of the processing apparatus can be modified to optimize weld generation before weld generation. The orientation of the processing apparatus can, for example, be adapted to the workpiece. Alternatively and / or additionally, the settings of the sampling equipment generating the sampling beam and / or the processing equipment generating the processing beam can also be modified. The properties of the calibration weld may be the weld penetration, porosity, and / or porosity size of the calibration weld.

[0033] Additionally, the method may include at least one of the following steps: determining the relationship between the properties of the calibrated weld, the desired properties of the weld, and the laser performance used to generate the processing beam that produces the calibrated weld; adjusting the laser performance according to the relationship of the calibrated weld; and as a result, achieving the desired properties of the weld when it is produced. Specifically, the laser performance is determined based on the calibrated weld according to the relationship before weld production. The calibrated weld may form part of a later-produced weld, or it may illustrate the entire process of a later-produced weld.

[0034] Therefore, welds can be produced more precisely. The desired properties of the weld can be the target weld penetration, target number of pores and / or target pore size, and / or the target weld penetration, target number of pores and / or target pore size of a section of the weld.

[0035] Laser performance can be predetermined by an analog voltage (specifically a 0 to 10 volt signal). The analog voltage can be an input value from the processing equipment and / or the processing beam source.

[0036] The relationship between the two can be linear. The appropriate laser performance for producing the weld can be determined by multiplying the laser performance that produces the calibration weld by a factor. As an example, this factor can be determined by dividing the weld penetration depth in the calibration weld and / or a specific area and / or portion of the calibration weld by the target weld penetration depth.

[0037] The present invention also includes a processing apparatus, particularly a laser processing head for generating welds on a workpiece using a processing beam, configured to implement the method according to the invention. The processing apparatus includes a processing device comprising a processing beam source configured to generate the processing beam. The processing apparatus also includes a sampling device configured to scan the weld using the sampling beam. The processing apparatus further includes a focusing device and an evaluation device, the focusing device being configured to project and / or focus the processing beam and / or the sampling beam onto the workpiece, and the evaluation device being configured to determine at least one reprocessing location on the weld based on the scanning by the sampling device.

[0038] The sampling device can be positioned adjacent to the processing equipment and / or integrated into the housing with the processing equipment. A processing scanner that enables the processing beam to be displaced relative to the workpiece can be provided in the processing equipment. The processing scanner can allow the processing position on the workpiece to be displaced in at least one or two spatial directions. For example, the processing scanner can have at least one (especially two) movable mirrors by means of which the processing beam can be displaced in an aiming manner.

[0039] The sampling device may include a sampling scanner. The sampling beam may be coupled to the processing scanner via the sampling scanner and may be moved along the workpiece in one or both spatial directions by using the sampling scanner and the processing scanner.

[0040] In addition, the sampling device may include an optical coherence tomography (OCT) system, which can be used to perform measurements based on optical coherence tomography (OCT).

[0041] Focusing devices may include focusing lenses, particularly F-θ lenses.

[0042] An optical coherence tomography (OCT) imager can be configured to generate a sampling beam and a reference beam. The OCT imager may also include a sampling arm and a reference arm, wherein the sampling beam in the sampling arm is optically guided, and the reference beam in the reference arm is optically guided. The OCT imager may also include a sampling unit configured to perform OCT measurements by interfering the sampling beam and the reference beam to generate measurement data.

[0043] In particular, it should be noted that all features and properties described with respect to the apparatus and process can be applied by analogy to the method according to the invention, and are applicable and considered disclosed in the sense of the invention. Conversely, this means that structural features, i.e., features of the apparatus mentioned with respect to the method, can also be considered, claimed, and considered disclosed within the scope of the apparatus claims. Attached Figure Description

[0044] The invention will then be described by way of example with reference to the accompanying drawings. The drawings, description, and claims together contain a number of features. Those skilled in the art will also readily consider these features individually and reasonably combine them within the scope of the claims.

[0045] In the attached diagram: Figure 1 This is a schematic diagram of the processing apparatus according to the present invention; Figure 2 This is a sequence diagram of an embodiment of the method according to the present invention; Figure 3 This is a sequence diagram of another embodiment of the method according to the present invention; Figure 4 This is a sequence diagram of another embodiment of the method according to the present invention; Figure 5 This is a sequence diagram of another embodiment of the method according to the present invention; Figure 6 This is a sequence diagram of another embodiment of the method according to the present invention; Figure 7 It is the relationship between the weld penetration depth generated by producing the weld and the target weld penetration depth; Figure 8 It is the relationship between the weld penetration depth generated by reprocessing the weld and the target weld penetration depth; Figure 9 It is the relationship between the weld penetration depth generated by producing a calibration weld and the target weld penetration depth; Figure 10 This is the relationship between the weld penetration depth generated by producing a calibration weld and the target weld penetration depth; and Figure 11 It is the relationship between the weld penetration depth generated by reprocessing the weld and the target weld penetration depth. Detailed Implementation

[0046] Figure 1 A processing apparatus 100, a processing device 60, a sampling device 70, and an evaluation device 80 are shown for generating a weld 10 on a workpiece 20 using a high-energy processing beam 30.

[0047] The sampling device 70 shows an optical coherence tomography (OCT) imager 170 that generates a sampling beam 40 and receives measurement points on the workpiece 20, particularly on and / or within the weld 10, via the sampling beam 40. The path of the sampling beam 40 can be predetermined, in particular, by a control device (not shown) and / or an evaluation device 80. The sampling beam 40 can be collimated by a sampling beam collimating lens 150 and can be deflected towards the processing device 60 by a sampling scanner 140. Specifically, the sampling scanner 140 can be configured to shift the sampling beam 40 in one and / or two spatial directions. For this purpose, the sampling scanner 140 can include two movable mirrors, each capable of corresponding shift in one spatial direction.

[0048] The processing apparatus 60 specifically includes a processing scanner 120, a partially transparent reflector 130 for coupling a sampling beam 40 to the processing beam, and a focusing lens 110. The processing scanner 120 can be configured to move the processing beam 30 in one and / or two spatial directions. For this purpose, the processing scanner 120 may include two movable reflectors, each capable of a corresponding displacement in one spatial direction. In this case, the sampling beam 40 can be coupled to the processing beam 30, such that the sampling beam 40 can also be displaced by the processing scanner 120. Therefore, the sampling beam 40 can be displaced by both the sampling scanner 140 and the processing scanner 120, while the processing beam 30 can be displaced by the processing scanner 120. By using this arrangement, the sampling beam 40 can be deflected relative to the processing beam 30.

[0049] For example, the sampling beam 40 is coupled into the processing apparatus 60 via a partially transparent reflector 130 and is subsequently deflected by the processing scanner 120. The sampling beam 40 is then guided onto the workpiece 20, for example, via a focusing lens 110 (particularly an F-θ lens). The sampling apparatus 70, particularly the coherence tomography imager 170, can be specifically configured to scan the weld 10 on the workpiece 20 by adjusting the sampling scanner 140 and / or the processing scanner 120.

[0050] The processing apparatus 60 may include a processing beam source 65 that generates a processing beam 30. In some embodiments, the processing beam 30 is collimated by a processing beam collimating lens 160. Subsequently, the processing beam 30 is guided and / or focused onto the workpiece 20, particularly through a partially transparent reflector 130, a processing scanner 120, and a focusing lens 110. Figure 1 The processing beam source 65 is shown only schematically in the diagram. The processing beam source 65 can be connected to... Figure 1 The components shown are spatially separated. The processing beam 30 can be coupled to the optical input port of a processing head, which includes the aforementioned lens and / or scanner. Similarly, the optical coherence tomography (OCT) imager 170, or at least its interferometer and / or its reference arm, can be located outside the processing head. The sampling beam 40 is then fed to the processing head, for example, via the sampling arm fiber. Therefore, it should be understood that... Figure 1 The arrangement of the components is merely to visualize the functional principles.

[0051] The machining beam 30 is specifically guided onto the workpiece 20 along the machining path. In particular, by adjusting the machining scanner 120, it can be ensured that the machining beam 30 follows the machining path. The adjustment of the first machining scanner 120 can be predetermined by the machining equipment 60 (especially by the control device).

[0052] The evaluation device 80 can adjust the laser performance of the processing device 60 (especially the processing beam source 65) to generate the processing beam 30 based on the measurement points of the coherence tomography imager 170. Specifically, the evaluation device can send a 0 to 10 volt signal to the processing beam source 65, through which the laser performance can be predetermined, and the processing device 60 (especially the processing beam source 65) uses the laser performance to generate the processing beam 30.

[0053] Figure 2 and Figure 3Sequence diagrams of different embodiments of the method for generating welds on a workpiece using a high-energy processing beam according to the present invention are shown. The method includes step S1, “generating a weld,” wherein a weld is generated on the workpiece by a processing beam. The method further includes step S2, “scanning the weld,” wherein the weld is scanned by a sampling beam. In step S2, “scanning the weld,” measurement points can be determined on the weld. The method further includes step S3, “determining reprocessing locations,” wherein reprocessing locations are determined based on measurement points determined in step S2 where the weld penetration is lower than the target weld penetration and / or the pore size exceeds the target pore size and / or the porosity exceeds the target porosity. Furthermore, the method includes step S4, “reprocessing the weld at at least one reprocessing location,” wherein the weld is reprocessed at at least one reprocessing location by a processing beam.

[0054] like Figure 2 As shown, steps S1 to S4 can be executed sequentially, one after another. Alternatively, steps S1 to S3 can be executed at least partially in parallel with each other, as shown below. Figure 3 As shown. For example, the measurement points determined in step S2 can be continuously sent to step S3. Alternatively, steps S1 and S2, or steps S2 and S3, can be executed in parallel with each other.

[0055] exist Figures 4 to 8 In other embodiments of the method according to the invention shown, steps S1 to S4 are illustrated sequentially, one after another. However, as Figure 3 As shown, at least steps S1 to S3 can be executed in parallel with each other. Figures 4 to 8 In the embodiments shown, steps S1 and S2 or steps S2 and S3 may also be performed in parallel with each other.

[0056] Figure 4 A sequence diagram of another embodiment of the method according to the present invention is shown. Figure 2 and Figure 3 Compared to the embodiments shown, Figure 4 The illustrated embodiment further includes step S5, “determining the relationship at the reprocessing location”, and step S6, “adjusting laser performance”.

[0057] In step S5, the relationship between the properties of the weld at the rework location, the desired properties of the weld, and the laser properties used to generate the processing beam that produces the weld at the rework location is determined. These properties may be the weld penetration depth, pore size, and / or porosity, and / or may be located within a defined portion and / or section of the weld. The desired properties may be the target weld penetration depth, target pore size, and / or target porosity, and / or may be located within a defined portion and / or section of the weld.

[0058] In step S6, the laser performance is adjusted according to the relationship. For example, the laser performance is adjusted at the reprocessing location. The laser performance can be adjusted at different reprocessing locations according to different relationships.

[0059] Therefore, steps S5 and S6 ensure accurate reprocessing of the weld at the reprocessing location. Figure 4 As shown, steps S5, S6, and S4 can be performed sequentially and / or at least partially in parallel with each other. For example, steps S6 and S4 can begin after step S5 determines the relationship at the reprocessing location.

[0060] Figure 5 A sequence diagram of another embodiment of the method according to the present invention is shown. Figure 4 Compared to the embodiments shown, Figure 5 The illustrated embodiment further includes an additional step S3', which is performed after step S4 to check the quality of the reprocessing. If at least one reprocessing location is identified in the re-executed step S3', steps S5, S6, and S4 can be executed again. Otherwise, the method is terminated.

[0061] Figure 6 A sequence diagram of another embodiment of the method according to the present invention is shown. Figure 2 and Figure 3 Compared to the embodiments shown, Figure 6 The illustrated embodiment further includes steps S10 "generating a calibration weld", S11 "determining the nature of the calibration weld", S12 "determining a relationship based on the calibration weld", and S13 "adjusting laser performance based on the relationship according to the calibration weld".

[0062] In step S10, a calibration weld is generated by processing a beam.

[0063] Subsequently, in step S11, the properties of the calibrated weld are determined by sampling beams. These properties may be the weld penetration, pore size, porosity, and / or orientation, and / or may be located in a defined portion and / or section of the weld.

[0064] In step S12, the relationship of the calibration weld is determined. This involves determining the relationship between the properties of the calibration weld, the desired properties of the weld, and the laser performance used to generate the processing beam that produces the calibration weld. The desired properties may be the target weld penetration, target pore size, and / or target porosity of the weld, and / or may be located within a defined portion and / or section of the weld. In step S13, the laser performance is adjusted according to the relationship of the calibration weld. Therefore, in the subsequent step S1, a weld with reduced reprocessing locations can be produced.

[0065] exist Figure 6In embodiments of the method shown, steps S12 and S13 may be omitted. For example, the orientation of the processing apparatus and / or processing equipment may be adjusted for the workpiece based on step S11 before performing step S1. Figure 6 The embodiments of the method shown, and therefore at least one of steps S10 to S13, can be combined with Figure 3 , Figure 4 or Figure 5 Each combination in the embodiments shown.

[0066] Figure 7 and Figure 8 The weld penetration is shown after different method steps in an embodiment of the method for producing a weld according to the present invention. Figure 7 The relationship between the weld penetration depth (solid line) along the x-axis of the workpiece and the target weld penetration depth (horizontal dashed line) is shown. Weld penetration depth can be achieved by creating a weld. Figure 7 As shown, the target weld penetration depth cannot be achieved across the entire x-axis of the workpiece. Figure 7 The rework position 50 (between the two vertical dashed lines) is also shown where the weld penetration is lower than the target weld penetration.

[0067] Figure 8 The relationship between the weld penetration depth (solid line) and the target weld penetration depth (horizontal dashed line) along the x-axis of the workpiece is shown. Weld penetration depth can be achieved by reworking the weld at the rework location. Preferably, the weld is selectively and specifically reworked only at the rework location, and the entire weld corresponds to the target weld penetration depth after rework, such as... Figure 8 As shown.

[0068] Figure 9 , Figure 10 and Figure 11 The following diagram illustrates the weld penetration depth after different method steps in an embodiment of the method for producing a weld according to the present invention. Figure 9 The relationship between the weld penetration depth (solid line) along the x-axis of the workpiece and the target weld penetration depth (horizontal dashed line) is shown. Weld penetration depth can be generated by creating a calibration weld. Figure 9 As shown, the target weld penetration depth cannot be achieved in one pass along the entire x-axis of the workpiece. Based on weld calibration and Figure 9 The relationships shown can be used to adjust the laser performance to generate the processing beam. Figure 10 The relationship between the weld penetration depth (solid line) along the x-axis of the workpiece and the target weld penetration depth (horizontal dashed line) is also shown. Weld penetration depth can be achieved by creating a weld. For example... Figure 10 As shown, the target weld penetration cannot be achieved along the entire x-axis of the workpiece. This means that the entire x-axis of the weld must be re-machined, thus creating a re-machining area. Figure 11The relationship between the weld penetration depth (solid line) along the x-axis of the workpiece and the target weld penetration depth (horizontal dashed line) is shown. Weld penetration depth can be achieved by re-machining the weld at the re-machining location. Preferably, the entire weld re-machining corresponds to the target weld penetration depth, such as... Figure 11 As shown.

[0069] In some embodiments, special selection may be made Figures 9 to 11 The process illustrated reliably, efficiently, and with high quality achieves the desired target weld penetration depth, and in particular, without unexpected full penetration and / or over-penetration. To achieve this, insufficient properties are initially selected for the processing bundle to produce the profile. Typically, an excessively deep weld penetration can be actively selected to validate the parameters chosen to achieve full penetration, thereby determining which parameters lead to full penetration. This can at least serve as a reference and can result in a progressively deeper weld effectively approaching the ideal value without full penetration. Alternatively or additionally, micrographs of the resulting weld can be generated.

[0070] By using the method according to the invention, computationally intensive weld penetration control is no longer required. Therefore, expensive computing units, which potentially require graphics boards that cannot be directly integrated into the processing equipment due to their size, are no longer needed. Furthermore, the data used for calculating weld penetration control no longer needs to be transmitted from the processing unit to the computing unit and vice versa. Therefore, the complex and computationally intensive online calculations for weld penetration control are no longer necessary.

[0071] High quality can be achieved by using the method according to the invention. Even if equipment for determining online weld penetration is available, welding results that might not be achievable by determining online weld penetration alone can be achieved by subsequently identifying the locations requiring rework and precisely reworking those locations. In particular, this takes into account the fact that even if online weld penetration is determined, future readings that could affect the quality of the determination are not available. However, separating the identification of welding and weld penetration in time allows these readings to be considered and used, for example, for notification and fitting. Furthermore, this prevents over-control, especially during the setting time of weld penetration.

[0072] In principle, computationally intensive weld penetration control is also unnecessary. Therefore, expensive computing units, which potentially require expensive graphics boards, will no longer be needed. Furthermore, the data used for calculating weld penetration control no longer needs to be transmitted in real-time from the machining unit to the computing unit and vice versa. Therefore, complex and computationally intensive online calculations for weld penetration control are no longer absolutely necessary.

[0073] By using the method according to the invention, it is more likely to determine the reprocessing location directly and / or offline on the evaluation unit, which can be integrated into the processing apparatus. As a result, production costs incurred when producing welds can be significantly reduced while maintaining sufficient and / or consistent weld quality.

[0074] List of reference numerals

[0075] S1 produces a weld.

[0076] S2 Scan Weld

[0077] S3 and S3' determine the reprocessing location.

[0078] S4 The weld shall be reworked at least at one rework location.

[0079] S5 Determine the relationship at the reprocessing location

[0080] S6 Adjust laser performance

[0081] S10 generates calibration welds

[0082] S11 Determine the nature of the calibration weld

[0083] S12 Determining Relationships Based on Calibrated Welds

[0084] S13 Adjusting laser performance based on the relationship of the calibrated weld seam

[0085] 10 Welds

[0086] 20 workpieces

[0087] 30 processing bundles

[0088] 40 sampling beams

[0089] 60 processing equipment

[0090] 65 Processing Beam Source

[0091] 70 Sampling equipment

[0092] 80 Evaluation Equipment

[0093] 100 processing equipment

[0094] 110 Focusing Lens

[0095] 120 Process Scanner

[0096] 130 reflector

[0097] 140 sampling scanner

[0098] 150 sampling beam collimating lens

[0099] 160mm collimating lens

[0100] 170 coherence tomography

Claims

1. A method for generating a weld (10) on a workpiece (20) using a high-energy processing beam (30), comprising the following steps: The weld (10) is produced on the workpiece (20) by the processing beam (30) (S1); The weld (10) is scanned (S2) by the sampling beam (40) of the optical coherence tomography (OCT) instrument. Identify (S3) at least one rework location where the weld penetration is less than the target weld penetration, and / or the porosity exceeds the target porosity at the rework location, and / or the porosity exceeds the target porosity at the rework location; as well as The weld (10) is reprocessed at least at one reprocessing location by the processing bundle (30) (S4).

2. The method according to claim 1, in, Reprocessing of the weld (10) is performed selectively at the reprocessing location (50) and / or at a plurality of the reprocessing locations (50) (S4).

3. The method according to any one of claims 1 or 2, in, The processing beam (30) is generated by the processing equipment (60), and the sampling beam (40) is generated by the sampling equipment (70). The processing equipment (60) and the sampling equipment (70) are part of the processing apparatus (100). The determination (S3) of the reprocessing position (50) is performed in the evaluation device (80) provided in the processing apparatus (100).

4. The method according to any one of the preceding claims, in, The rework location (50) is determined (S3) during and / or after scanning (S2) the weld.

5. The method according to any one of the preceding claims, in, The determination (S3) of the reprocessing location (50) is based on multiple measurement points and / or a single measurement point, which are identified when the sampling beam (40) scans (S2) the weld.

6. The method according to any one of the preceding claims, It also includes the following steps: The relationship between the properties of the weld (10) at the reprocessing position (50), the desired properties of the weld (10), and the laser properties used to generate the processing beam that produces the weld (10) at the reprocessing position (50) is determined (S5). as well as At the reprocessing position (50), the laser performance is adjusted (S6) according to the relationship. Specifically, determining (S5) the relationship at the reprocessing position (50) and adjusting (S6) the laser performance are performed before (S4) the weld (30) is reprocessed at the reprocessing position (50) and after (S3) the reprocessing position (50) is determined.

7. The method according to any one of the preceding claims, It also includes the following steps: Re-determine (S3') at least one rework location (50) where the weld penetration is less than the target weld penetration and / or the porosity exceeds the target porosity and / or the porosity exceeds the target porosity. After the weld (30) is reprocessed at the at least one reprocessing position (50) (S4), the at least one reprocessing position (50) is redefined (S3').

8. The method according to any one of the preceding claims, It also includes the following steps: The calibration weld is generated by processing the beam (30) (S10); The properties of the calibrated weld (S11) are determined by sampling beams. Before generating the weld (30), the generation (S10) calibration weld and the determination (S11) calibration weld properties are performed.

9. The method according to claim 8, It also includes the following steps: Determine (S12) the relationship between the properties of the calibration weld, the desired properties of the weld (10), and the laser performance used to generate the processing beam (30) that produces the calibration weld; The laser performance is adjusted (S13) according to the relationship of the calibrated weld. Specifically, before generating the weld (S1) (10), the relationship is determined based on the calibrated weld (S12), and the laser performance is adjusted based on the calibrated weld according to the relationship (S13).

10. The method according to any one of claims 6 to 9, in, The properties mentioned are weld penetration depth, number of pores and / or pore size, and / or The desired properties are the target weld penetration, the target number of pores, and / or the target pore size.

11. A processing apparatus (100) configured to perform the method according to any one of the preceding claims for generating a weld (10) on a workpiece (20) by means of a processing bundle (30), comprising: The processing equipment (60) includes a processing beam source (65) configured to generate the processing beam (30). A sampling device (70) is configured to scan the weld (10) using a sampling beam (30); A focusing device configured to project and / or focus the processing beam onto the workpiece (20); as well as An evaluation device (80) is configured to determine at least one rework location (50) on the weld (10) based on a scan by the sampling device (70).

12. The processing apparatus according to claim 11, in, The sampling device (70) includes an optical coherence tomography (OCT) imager configured to generate the sampling beam (30) and the reference beam. The optical coherence tomography system includes: The sampling arm, in which the sampling beam (30) is optically guided; A reference arm in which the reference beam is optically guided; A sampling unit configured to perform optical coherence tomography measurements by interfering the sampling beam (30) and the reference beam to generate measurement data.

Images