JP2021514309A - How to align a multi-beam irradiation system - Google Patents

Abstract

The method of aligning the multi-beam irradiation system 20 for use in the apparatus 10 for manufacturing a three-dimensional processed product by irradiating the layer of raw material powder with electromagnetic or particle radiation was emitted by i) the irradiation system 20. The step of applying the first raw material powder layer on the carrier 16 so as to define the irradiation plane S irradiated by the radiation beams 24a and 24b, and ii) the first irradiation unit 22a emitted by the calibrated first irradiation unit 22a of the irradiation system 20. The step of manufacturing the first test structure 34 on the first raw material powder layer in the overlapping zone 18c of the irradiation plane S using one radiation beam 24a and iii) emitted by the calibrated second irradiation unit 22b of the irradiation system 20. The step of manufacturing the second test structure 36 in the first raw material powder layer in the overlapping zone 18c of the irradiation plane S using the second radiation beam 24b, and iv) the first and second test structures in the irradiation plane S. The step of measuring the offset dxt, dyt between 34 and 36, and v) the first based on the measured offset dxt, dyt between the first and second test structures 34, 36 so that the offset does not exceed the threshold. And a step of aligning at least one of the second configured irradiation units 22a, 22b.

Description

The present invention relates to a method of aligning a multi-beam irradiation system for use in an apparatus for producing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic radiation or particle radiation. Furthermore, the present invention relates to a method of operating an apparatus for producing a three-dimensional processed product by irradiating a layer of raw material powder by electromagnetic or particle radiation, which comprises a multi-beam irradiation system.

Powder bed melting is an additional lamination process that allows powders, especially metal and / or ceramic raw materials, to be processed into complex shaped three-dimensional processed products. To this end, the raw material powder layer is applied onto the carrier and is site-selectively exposed to laser radiation, depending on the desired shape of the processed product to be manufactured. Laser radiation penetrating the powder layer causes heating of the raw material powder particles, thus melting or sintering. Then, additional raw material powder layers are sequentially applied to the layers on the carriers that have already been irradiated until the processed product has the desired shape and size. Selective laser melting or laser sintering can be used, for example, in the manufacture of prototypes, tools, replacement parts, or medical prostheses such as dental or orthopedic prostheses, based on CAD data.

An apparatus for producing a cast from a powder raw material by a powder bed melting process is described, for example, in European Patent No. 1793979 (B1) (Patent Document 1). The prior art device comprises a process chamber accommodating multiple carriers for the part to be manufactured. The powder layer penetration system includes a powder container holder that can move the entire carrier back and forth and left and right to apply the raw material powder irradiated by the laser beam onto the carrier. The process chamber is connected to a protective gas circuit having a supply line, through which the protective gas can be supplied to the process chamber to establish a protective gas environment in the process chamber.

A typical irradiation system that can be adopted in an apparatus for producing a three-dimensional processed product by irradiating a powder raw material is described in European Patent No. 2335848 (B1) (Patent Document 2). The irradiation system includes a radiation source, particularly a laser source, and an optical unit. The optical unit to which the radiation beam emitted by the radiation source is given includes a beam expander, a scanner unit, and an objective lens designed in the form of an fθ lens.

In order to calibrate the irradiation system, and especially the optical unit used in the equipment for producing three-dimensional processed products by irradiating the powder raw material, so-called burn-off foil is used to irradiate the raw material powder to be irradiated during normal operation of the equipment. Can be applied to the carrier that supports the layer. After that, the burn-off foil is irradiated according to a preset pattern, and a burn-off image of the irradiation pattern is developed on the foil. The burn-off image is digitized and compared with a digital reference image of the irradiation pattern. Based on the results of the comparison between the digitized burn-off image and the reference image, the irradiation unit is calibrated to correct the deviation between the actual burn-off image and the reference image. Alternatively, a digital image of the irradiation pattern generated by the radiation beam incident on the sensor array arranged on the irradiation plane can be obtained by using an irradiation system as described in European Patent No. 3241668 (A1) (Patent Document 3). Can be used to calibrate.

Especially in order to produce larger objects or to increase the production rate, for example, in European Patent No. 2875897 (B1) (Patent Document 4) or European Patent No. 2862651 (A1) (Patent Document 5). The multi-beam irradiation system described can be adopted. Such a multi-beam irradiation system includes a plurality of irradiation units for emitting a plurality of radiation beams. Each of the radiated beams typically operates in a designated limited irradiation zone and one or more overlapping zones.

Even if the irradiation units of the multi-beam irradiation system are individually calibrated, for example as described above, the radiation beams emitted by the irradiation system typically show some degree of misalignment in the overlapping zones. In particular, radiated beams pointing at the same xy coordinates in the overlapping zone can also be offset from each other. This offset can affect the quality of the work piece to be manufactured.

European Patent No. 3202524 (A1) discloses a method of aligning a pair of calibrated lasers in a laser addition manufacturing system in an overlapping region in which the pair of calibrated lasers selectively operate. In this method, in the first step, the first plurality of layers of the test structure are formed in the overlapping region using only the first calibrated laser of the pair of calibrated lasers. In the second step, a second plurality of layers of the test structure are formed in the overlapping region using a second calibrated laser of a pair of calibrated lasers. The dimensions of the offset steps that occur between the first and second layers of the outer surface of the test structure are then measured and offset steps as alignment corrections for at least one of the paired calibrated lasers. By applying the dimensions of, the pair of calibrated lasers are aligned.

European Patent No. 1793979 (B1) European Patent No. 2335848 (B1) European Patent No. 3241668 (A1) European Patent No. 2875897 (B1) European Patent No. 2862651 (A1) European Patent No. 3202524 (A1)

The present invention provides a reliable and efficient method for aligning a multi-beam irradiation system for use in an apparatus for manufacturing a three-dimensional work piece by irradiating a layer of raw material powder with electromagnetic or particle radiation. The purpose is to do. Further, the present invention comprises an apparatus for producing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic or particle radiation, comprising a multi-beam irradiation system aligned according to the above-mentioned reliable and efficient alignment method. It is intended to provide a method of operating.

These objectives are achieved by the method of aligning the multi-beam irradiation system specified in claim 1 and the method of operating the device for manufacturing the three-dimensional processed product specified in claim 19.

In a method of aligning a multi-irradiation system for use in an apparatus for manufacturing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic or particle radiation, the first raw material powder layer is a multi-beam irradiation system. It is applied onto the carrier so as to define the irradiation plane irradiated by the radiation beam emitted by. The carrier can be placed in a process chamber that can be sealed to the surrounding environment in order to maintain a controlled environment, especially an inert environment, in the process chamber. The raw material powder can be a metal powder, but can also be a ceramic powder, a plastic material powder, or a powder containing a different material. The powder can have any suitable particle size or particle size distribution. However, it is preferable to treat a powder having a particle size <100 μm.

The irradiation plane is the plane of the raw material powder layer that receives the radiation beam emitted by the multi-beam irradiation system. Typically, the irradiation plane coincides with the top plane of the raw material powder layer. The position of the upper surface plane of the raw material powder layer with respect to the surface of the carrier is useful for positioning the powder coating device for applying the raw material powder layer on the carrier, and particularly for smoothing the upper surface of the raw material powder layer. It may depend on the positioning of the equipment leveling slider.

The multi-beam irradiation system can include a radiation source, particularly a laser source, such as a diode-pumped ytterbium fiber laser. A multi-beam irradiation system can include only one source. However, it can be assumed that the multi-beam irradiation system includes a plurality of radiation sources. In addition, the multi-beam irradiation system can include two or more irradiation units. Each irradiation unit can include a plurality of optical elements including, for example, a beam expander for expanding a radiation beam emitted by a radiation source, a scanner, and an objective lens. Alternatively, the plurality of optical elements provided to each of the irradiation units may include a beam expander including a focusing lens and a scanner unit. Depending on the scanner unit, the position of the focal point of the radiated beam can be changed and adapted in a plane that is perpendicular to the beam path as well as the direction of the beam path. The scanner unit can be designed in the form of a galvanometer scanner, and the objective lens can be an fθ objective lens.

In a further step in the method of aligning the multi-beam irradiation system, the first test structure uses the first radiation beam emitted by the calibrated first irradiation unit to use the first raw material powder layer in the overlapping zone of the irradiation plane. Manufactured in. Further, a second test structure is produced in the first raw material powder layer in the overlapping zone of the irradiation plane using the second radiation beam emitted by the calibrated second irradiation unit. "Overlapping zone" as used herein refers to a region of the irradiation plane that can be irradiated by the radiation beams of both the first and second irradiation units. Therefore, the first and second test structures are manufactured in the region of the irradiation plane where both the first radiation beam emitted by the first irradiation unit and the second radiation beam emitted by the second irradiation unit are accessible. Radiation.

The first and second irradiation units of the multi-beam irradiation system can be calibrated prior to performing the method of aligning the multi-beam irradiation system. In addition, calibration of individual irradiation units can be performed simultaneously or sequentially. To calibrate the irradiation unit, use any calibration method, such as burn-off foil, as long as it is suitable to substantially eliminate the offset of the radiation beam emitted by the irradiation unit with respect to the set coordinates or reference pattern in the irradiation plane. The calibration method or the calibration method described in European Patent No. 3241668 (A1) (Patent Document 3) can be used.

Then in the step, the offset between the first and second test structures in the irradiation plane is measured. Basically, it is assumed that the offset between the first and second test structures is measured in only one direction in the irradiation plane. However, it is preferable that the offset between the first and second test structures is measured in two directions in the irradiation plane. If necessary, for example, when the offset between the first and second test structures should be measured in two directions in the irradiation plane, or when the multi-beam irradiation system includes more than two irradiation units, multiple pairs. The first and second test structures can be manufactured.

At least one of the first and second irradiation units is then aligned based on the measurement offset between the first and second test structures in the irradiation plane. In particular, at least one of the first and second irradiation units is aligned so that the offset between the first and second test structures in the irradiation plane is kept below the threshold, especially below the threshold. Preferably, the first and second test structures are shaped so that the measurement offset between the first and second test structures in the irradiation plane can be used directly for alignment of at least one of the first and second irradiation units. Has an array.

In the method of aligning the multi-beam irradiation system, both the first test structure and the second test structure are manufactured in the first raw material powder layer. That is, the first and second test structures are manufactured in the same raw material powder layer. As a result, the first and second test structures can be manufactured at the same time, reducing the time required to form the test structures. In addition, the test structure has a low build height while ensuring that the offset between the first and second test structures that occurs in the irradiation plane when the first and second irradiation units are not aligned can be measured. Can be modeled.

In the method of aligning the multi-beam irradiation system, a step of applying a raw material powder layer on a carrier, a step of manufacturing a first test structure on the applied powder layer, and a second test structure on the applied powder layer. At least one of the manufacturing steps can be repeated before measuring the offset between the first and second test structures and before aligning at least one of the first and second calibrated irradiation units. In this way, a multi-layered first test structure and / or a multi-layered second test structure can be manufactured.

In the method of aligning the multi-beam irradiation system, only one first test structure and only one second test structure can be manufactured. However, it is also assumed that the method includes the production of a plurality of first test structures and a plurality of second test structures. The test structures can be manufactured in pairs, where each pair of test structures can measure and / or average the offset between the first and second test structures in two directions, eg, in the irradiation plane. Includes first and second test structures to measure values.

The first test structure and the second test structure can be manufactured during the alignment operation of the device for manufacturing the three-dimensional processed product. The alignment operation of the device can be performed separately from the normal operation of the device for manufacturing the 3D work piece, for example, after calibrating the individual irradiation units of the multi-beam irradiation system, but to manufacture the 3D work piece. It can be carried out before the start of normal operation of the device for. In other words, the calibration / alignment of the device and the normal operation of the device can be separated, and the normal operation of the device for manufacturing the three-dimensional work piece can be started only after the calibration / alignment process is completed. Alternatively or additionally, it can be assumed that the first test structure and the second test structure are manufactured during normal operation of the apparatus for manufacturing the three-dimensional processed product. That is, the first and second test structures and the three-dimensional processed product can be manufactured at the same time by a single modeling process.

The first test structure and the second test structure can be manufactured in the form of massive components. The test structure produced in the form of a mass component can be connected to a substrate plate placed on the carrier and coated with a subsequent raw material powder layer to form the test structure on the substrate plate. In addition, the test structure produced in bulk form can include as many layers as the number of layers of the three-dimensional work piece produced at the same time. Therefore, the test structure in the form of a mass component can be manufactured at a molding height that matches the molding height of the three-dimensional processed product. However, it can be assumed that the test structure manufactured in the form of a mass component contains a number of layers smaller than the number of layers of the three-dimensional processed product manufactured at the same time. A single-layer test structure can also be envisioned. If the first and second test structures are manufactured in the form of massive components, the dimensions and shape of the test structures can be measured to measure the offset between the first and second test structures, while To measure the offset between the first and second test structures, the test structure can remain attached to or detached from the carrier or substrate plate.

Alternatively, the first test structure and the second test structure can be manufactured in the form of a lost component, which is formed separately from the substrate plate and the carrier. Preferably, the test structure manufactured in the form of a lost component contains fewer layers than the number of layers of the three-dimensional work piece manufactured at the same time. A single layer test structure can also be envisioned.

When the first and second test structures are manufactured in the form of lost components, at least one layer of the first and second test structures is shaped at a predetermined distance from the carrier and is simultaneously manufactured tertiary. It can be arranged in the same plane as the intermediate layer of the original processed product. In addition, the layers of the test structure are expected to be manufactured regularly or randomly or algorithmically. For example, the layers of the five test structures can be manufactured in the same plane as the five processed product layers for every 20 layers of the processed product.

The offset between the first and second test structures can be measured after the production of the first and second test structures is complete. For example, at least one dimension and / or shape of the test structure can be measured manually after the production of the test structure is complete with the help of suitable manual measurement tools. Alternatively or additionally, the offset between the first and second test structures is, for example, during the manufacture of the first and second test structures, for example, in one layer of the first and second test structures. It can be measured after completion and before starting the production of additional layers of the first and second test structures.

Optical measuring instruments such as cameras or optical sensors can be used to measure the offset between the first and second test structures. In a particularly preferred embodiment of the method of aligning a multi-beam irradiation system, the offset between the first and second test structures is the melt pool monitoring system, the melt produced in the process of introducing radiant energy into the raw material powder. Measured by optical measuring instruments that form the components of the system for observing the pool. Alternatively, the optical measuring instrument used to measure the offset between the first and second test structures is on the carrier to detect defects or irregularities in the layer control system or raw material powder layer. It can be constructed by the components of the system for monitoring the applied raw material powder layer. The use of optical measuring instruments allows the offset between the first and second test structures to be measured during the manufacture of the first and second test structures. However, it can be assumed that an optical measuring instrument is used to manually or automatically measure the offset between the first and second test structures after the production of the first and second test structures is completed.

The optical measuring instrument used to measure the offset between the first and second test structures is configured to detect thermal radiation and output an intensity value indicating the strength of the detected thermal radiation. It can be designed in the form of high temperature detection equipment. Typically, the intensity of the heat radiation emitted from the surface of the previously solidified test structure is different from the heat radiation emitted from the non-solidified raw material powder surrounding the solidified test structure. Therefore, the location of the boundary between the test structure and the raw material powder surrounding the test structure can be measured based on the heat radiation detected by the high temperature detection device.

To measure the offset between the first and second test structures, after completion of one layer of the first and second test structures, the region of the irradiation plane containing the first and second test structures It can be scanned with a test emission beam emitted by at least one of the first and second irradiation units. When the optical measuring instruments forming the components of the melt pool monitoring system are coupled to one of the first and second irradiation units, only the irradiation units coupled to the optical measuring instruments are the first and second test structures. Can be used to scan an area of the irradiation plane that contains. The area of the irradiation plane to be scanned is not only the area where the first and second test structures manufactured by the perfectly aligned first and second irradiation units are expected to be located, but also the area to be irradiated. Is set to include the surrounding area to include the first and second test structures that are offset from each other due to the misalignment of the first and second irradiation units.

When scanning an area of the irradiation plane that includes the first and second test structures, at least one of the first and second test radiation beams and the first and second test structures or the first and second in the irradiation plane. 2 Interactions with the raw material powder surrounding the test structure are monitored by optical measuring instruments. When at least one of the first and second test emission beams is incident on the non-solidified raw material powder, the intensity value detected by the optical measuring instrument is typically that at least one of the first and second test emission beams was previously Higher than the intensity value detected by the optical measuring instrument when incident on the surface of the solidified test structure.

As a result, the location of the boundary line between the first and second test structures and the raw material powder surrounding the first and second test structures is at least one of the first and second test radiation beams and the first and second test radiation beams. It can be measured based on the interaction between the two test structures and the raw material powder surrounding the first and second test structures in the region of the irradiation plane containing the first and second test structures. In this way, the offset between the first and second test structures can also be detected.

Preferably, the region of the irradiation plane containing the first and second test structures forms a predetermined angle, especially at right angles, to the first plurality of scan vectors and the first plurality of scan vectors extending in the irradiation plane. It is scanned according to a pattern containing a second plurality of scan vectors extending in the irradiation plane. The spacing between the parallel scan vectors of the scan pattern allows accurate measurement of the location of the boundary between the first and second test structures and the raw material powder surrounding the first and second test structures. Must be kept small enough to be.

Preferably, the parallel scan vectors of the first and / or second plurality of scan vectors are unidirectional. Signals detected by optical instruments, especially high temperature instruments in meltpool monitoring systems, in the transition area from the raw material powder to the previously solidified test structure surface are transferred from the previously solidified test structure surface to the raw material powder. Different from the signal detected by the optical measuring device in the area. Such signal differences are negligible when one-way scanning steerability is employed when scanning the area of the irradiation plane that includes the first and second test structures.

The region of the irradiation plane containing the first and second test structures preferably has a beam power lower than the beam power and / or scan rate of the first or second radiation beam at the time of manufacture of the first and second test structures. And / or scanned with a test emission beam at scan rate. By lowering the beam power and scan rate, a signal indicating the interaction between the test emission beam and the surface of the previously solidified test structure is distinguished from the interaction between the test emission beam and the non-solidified raw material powder. Helps. In addition, lowering the scan speed reduces signal noise and increases the amount of data detected. As a result, the detection accuracy can be improved. The beam power of the test radiation beam may be zero, which means that the region of the irradiation plane containing the first and second test structures can be scanned without irradiation with a test radiation beam with positive beam power. .. However, irradiating the region of the irradiation plane including the first and second test structures with a test radiation beam with a beam power higher than zero easily distinguishes it from background noise because the detected thermal radiation signal is amplified. It has the advantage of being able to do it.

In addition to or instead of using optical measuring instruments configured to detect the thermal radiation emitted by the first and second test structures and the raw material powder around them, to capture an image of the plane of irradiation. It can be assumed that the offset between the first and second test structures will be measured with the help of the optical measuring instrument made. For example, an image pickup device of a layer control system of a device for manufacturing a three-dimensional processed product can be used for this purpose.

In particular, the step of measuring the offset between the first and second test structures includes capturing an image of the irradiation plane, especially a two-dimensional image, after the completion of one layer of the first and second test structures. Can be done. The captured image can include the entire irradiation plane or only the region of the irradiation plane containing the first and second test structures. In addition, the location of the boundary between the first and second test structures and the raw material powder surrounding the first and second test structures should be visually inspected by automated image processing or manually i.e. captured images. Can be measured based on the captured image of the irradiation plane. Therefore, the image pickup device of the layer control system can include a camera and an arbitrary image processing system.

At least one of the first and second calibrated irradiation units is measured between the first and second test structures so that the offset does not exceed the threshold after the production of the first and second test structures is completed. Can be aligned based on offset. In other words, the first and second test structures can be manufactured. In the next step, the offset between the first and second test structures in the irradiation plane is measured, after which the first and second irradiation units can be aligned according to the measurement offset.

Instead or in addition, at least one of the first and second calibrated irradiation units has first and second test structures so that the offset does not exceed the threshold during the manufacture of the first and second test structures. It can also be assumed that they will be aligned based on the measurement offset between the bodies. For example, the alignment procedure for aligning at least one of the first and second irradiation units is after the completion of one layer of the first and second test structures, but with additional layers of the first and second test structures. Can be done before the generation of. Aligning at least one of the first and second irradiation units to compensate for the offset between the first and second test structures during the manufacturing process of the first and second test structures is also particularly offset measurement. It is advantageous when it is carried out in the manufacturing process of the first and second test structures.

Preferably, the first test structure and the second test structure have at least one edge of the first test structure at least one of the second test structures when the first irradiation unit and the second irradiation unit are aligned. Manufactured to have a shape and arrangement that is aligned with the edges. The offset between the edges of the first and second test structures is emitted by the first irradiation unit and emitted by the first and second irradiation units used to manufacture the first test structure. Matches the offset with the second emission beam used to manufacture the test structure.

When the first irradiation unit and the second irradiation unit are aligned, the edges of the first and second test structures that are aligned with each other may extend parallel to the x direction in the irradiation plane, for example. it can. The offset between the edges indicates the offset between the first and second radiation beams in the y direction in the irradiation plane, i.e., at right angles to the x direction in the irradiation plane. On the contrary, when the first irradiation unit and the second irradiation unit are aligned, the edges of the first and second test structures arranged on the same plane extend parallel to the y direction in the irradiation plane. , The offset between the edges indicates the offset in the x direction between the first and second radiation beams in the irradiation plane. A test structure with edges parallel to the x and y directions or a pair rotated 90 degrees with each other to measure the offset between the first and second radiation beams in both the x and y directions. Test structure can be manufactured.

In one embodiment, the first test structure can have a rectangular shape and can be manufactured adjacent to a second test structure that also has a rectangular shape. In particular, the first and second test structures can have a congruent rectangular shape, and when the first and second irradiation units are aligned, the edges of the first test structure are in the x direction in the irradiation plane. Alternatively, they can be arranged side by side so that they are arranged parallel to the y direction and on the same plane as the edge in the second test structure. These test structures can be easily manufactured. Moreover, the offset between the test structures can be easily measured. However, if offsets in two directions within the irradiation plane must be measured, two pairs of test structures must be modeled.

Alternatively, the first and second test structures can be substantially linear and can form a cross when the first and second irradiation units are aligned. The design of such a test structure allows the offset of the radiation beam of the two-way irradiation unit in the irradiation plane to be measured with the help of a single pair of test structures. However, linear test structures are difficult to handle because the offset between the test structures is manually measured after the structure has been modeled. Therefore, it is preferable that the linear test structure is adopted for the offset measurement performed at the time of manufacturing the first and second test structures as described above.

In another embodiment, the first test structure is rectangular that fits into the cutout given to the second test structure, which is substantially L-shaped when the first and second irradiation units are aligned. Has. The first and second test structures can be arranged so that they are in contact with each other. However, in order to prevent the raw material powder region from being irradiated by both the first and second radiation beams due to the misalignment of the irradiation unit, the first and second test structures are arranged at a distance from each other. It can also be assumed. The design of the test structure, in which the first test structure fits into the cutout given to the second test structure, which is substantially L-shaped, is particularly designed to exceed two of the multi-beam irradiation systems, for example four irradiations. It is advantageous for aligning the units. For example, the L-shaped second test structure can be manufactured with the help of an irradiation system that will later be used as a reference system for aligning other irradiation systems.

In a more preferred embodiment for the method of aligning a multi-beam irradiation system, the first and second test structures are manufactured on a common base. The test structure can then be easily handled when measuring the offset from the substrate platform and / or from the carrier along with the common base, eg with the help of a manual measurement tool.

The method of operating the device for manufacturing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic or particle radiation equipped with a multi-beam irradiation system is as described above, the method of operating the device's multi-beam irradiation system. Includes aligning steps. A further layer of raw material powder is then applied onto the carrier and calibrated and aligned to produce a three-dimensional work piece while maintaining a constant distance between the beam emission plane and the irradiation plane. 2 Irradiated with the first and second radiation beams emitted by the irradiation unit. As a result, the alignment of the first and second irradiation units can be reliably maintained not only during the production of a single processed product, but also in the subsequent production process. This makes it possible to manufacture high-quality processed products even in the overlapping zone.

Used to apply a raw material powder layer onto a carrier to maintain a constant distance between the beam emission plane and the irradiation plane in a preferred embodiment of a method of operating an apparatus for producing a three-dimensional work piece. The powder coating equipment to be used is properly positioned with respect to the beam radiation plane. In particular, the leveling slider of the powder coating equipment, which is useful for leveling the raw material powder applied on the carrier, keeps the beam emission plane and the irradiation plane even after the maintenance of the powder coating equipment accompanied by the replacement of the leveling slider of the powder coating equipment. It can be properly positioned with respect to the beam emission plane so that a constant distance between them is maintained.

The distance between the beam emission plane and the irradiation plane must be set as accurately as possible. Therefore, the powder coating device is a positioning tool that allows the powder coating device to be positioned relative to the carrier, and in particular to be able to set the distance between the beam emission plane and the irradiation plane with an accuracy of ± 2 μm, preferably ± 1 μm. With the help, it can be positioned relative to the beam emission plane.

Preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings below.

FIG. 1 shows an apparatus for manufacturing a three-dimensional processed product by selectively irradiating raw material powder with electromagnetic waves or particle radiation. FIG. 2a shows the first radiation beam emitted by the first irradiation unit of the apparatus shown in FIG. 1 and the second radiation beam emitted by the second irradiation unit with respect to the distance between the beam emission plane and the irradiation plane. Shows the offset dependency between. FIG. 2b shows the first radiation beam emitted by the first irradiation unit of the apparatus shown in FIG. 1 and the second radiation beam emitted by the second irradiation unit with respect to the distance between the beam emission plane and the irradiation plane. Shows the offset dependency between. FIG. 2c shows the first radiation beam emitted by the first irradiation unit of the apparatus shown in FIG. 1 and the second radiation beam emitted by the second irradiation unit with respect to the distance between the beam emission plane and the irradiation plane. Shows the offset dependency between. FIG. 2d shows the first radiation beam emitted by the first irradiation unit of the apparatus shown in FIG. 1 and the second radiation beam emitted by the second irradiation unit with respect to the distance between the beam emission plane and the irradiation plane. Shows the dependency of the offset between. FIG. 2e shows the first radiation beam emitted by the first irradiation unit of the apparatus shown in FIG. 1 and the second radiation beam emitted by the second irradiation unit with respect to the distance between the beam emission plane and the irradiation plane. Shows the offset dependency between. FIG. 3a shows a first embodiment of the test structure design. FIG. 3b shows a first embodiment of the test structure design. FIG. 4a shows a second embodiment of the test structure design. FIG. 4b shows a second embodiment of the test structure design. FIG. 5a shows a third embodiment of the test structure design. FIG. 5b shows a third embodiment of the test structure design. FIG. 6a shows a modification of the third embodiment of the test structure design. FIG. 6b shows a modification of the third embodiment of the test structure design. FIG. 7a shows a manual measurement of the offset between the first and second test structures in the test structure design according to FIG. 6a. FIG. 7b shows a manual measurement of the offset between the first and second test structures in the test structure design according to FIG. 6b. FIG. 8 shows a positioning tool for positioning the powder coating device of the device shown in FIG. 1 in a state of being positioned in the build chamber of the device. FIG. 9 shows the positioning of the powder coating device 14 using the positioning tool shown in FIG.

FIG. 1 shows an apparatus 10 for manufacturing a three-dimensional processed product. The device 10 includes a process chamber 12. The powder coating device 14 arranged in the process chamber 12 is useful for coating the raw material powder on the carrier 16. In the arrangement of FIG. 1, the raw material powder layer 15 is applied onto the carrier 16. As indicated by the arrow A, the carrier 16 is located in the build chamber 19 so that the carrier 16 can move vertically downward as the constituent height of the work piece increases when stacked from the raw material powder on the carrier 16 into layers. It can move vertically inward. The powder coating device 14 includes a leveling slider 17 that helps level and smooth the raw material powder layer 15 coated on the carrier 16.

The first and second irradiation zones 18a and 18b are defined in a juxtaposed arrangement on the surface of the raw material powder layer 15 and on the carrier 16, respectively. That is, in the apparatus 10 shown in FIG. 1, the left half on the raw material powder layer 15 and the carrier 16 each defines the first irradiation zone 18a, and the right half of the raw material powder layer 15 and the carrier 16 each define the second irradiation zone 18b. Define. An overlapping zone 18c is defined in the boundary region between the first and second irradiation zones 18a and 18b.

The device 10 includes an irradiation system 20 for selectively irradiating the raw material powder coated on the carrier 16. The operation of the irradiation system 20 is controlled by the control device 21. The irradiation system 20 allows the raw material powder applied on the carrier 16 to be site-selectively radiated according to the desired shape of the processed product to be manufactured. The irradiation system 20 includes first and second irradiation units 22a and 22b. The first irradiation unit 22a irradiates the first irradiation zone 18a and the overlapping zone 18c defined on the surface of the raw material powder layer 15 with the first radiation beam 24a. The second irradiation unit 22b irradiates the second irradiation zone 18b and the overlapping zone 18c defined on the surface of the raw material powder layer 15 with the second radiation beam 24b.

The radiation beams 24a and 24b are emitted from the first and second irradiation units 22a and 22b in the beam radiation plane B. The upper surface of the raw material powder layer 15 defines an irradiation plane S, and the radiation beams 24a and 24b emitted by the irradiation units 22a and 22b are incident on the raw material powder in the irradiation plane. The distance between the irradiation plane S and the beam radiation plane B is indicated by D. As will be described in more detail below, the position of the irradiation plane S with respect to the beam radiation plane B, and thus the distance D between the irradiation plane S and the beam radiation plane B, is the powder coating device 14 with respect to the beam radiation plane B, especially the leveling slider. It depends on the position of the lower surface of 17. In order to position the powder coating device 14 exactly as desired, the device 10 positions the powder coating device 14 and thus the lower leveling surface of the leveling slider 17 with an accuracy of ± 2 μm, especially ± 1 μm, with respect to the beam radiation plane B. The positioning tool 27 is provided. The positioning tool 27 can be installed separately from the device 10 and inserted into the process chamber 12 of the device 10 only when necessary.

As shown in FIG. 8, the positioning tool 27 includes two leveling plates 40, 42 arranged in the irradiation plane S. In order to position the leveling plates 40 and 42 on the irradiation plane S, the positioning tool 27 includes a support structure 44 that spans the build chamber 19 of the device 10. Each of the leveling plates 40 and 42 is connected to distance measuring devices 46 and 48 for measuring the distance of the object to the leveling plates 40 and 42, respectively. The lever 50 helps raise and lower the leveling plates 40, 42 at a fixed distance between the upper and lower positions.

When using the positioning tool 27, the positioning tool 27 is arranged in the process chamber 12, and the positions of the leveling plates 40 and 42 are set so that the leveling plates 40 and 42 are arranged on the irradiation plane S. The leveling plates 40, 42 are then lowered by activating the lever 50 to allow the powder coating device 14 to be positioned above the leveling plates 40, 42 without colliding with the leveling plates 40, 42. After the powder coating device 14 reaches the desired location, the leveling plates 40 and 42 reach the irradiation plane S again so that the leveling plates 40 and 42 abut on the lower leveling surface of the leveling slider 17 as shown in FIG. Will be raised. The leveling slider 17 is then raised with the help of a micrometer screw 52 installed in the powder coating device 14 until its lower leveling surface is located at a desired distance, eg 200 μm ± 10 μm, from the leveling plates 40, 42. .. Once the position of the leveling slider 17 has been set, the leveling plates 40, 42 can be lowered again by activating the lever 50, the powder coating device 14 can be moved, and the positioning tool 27 can be removed from the process chamber 12.

Both irradiation units 22a, 22b are coupled with a diode-pumped ytterbium fiber laser that emits laser light from a laser beam source 26, eg, a wavelength of about 1070-1080 nm. Each of the first and second irradiation units 22a, 22b guides and / or guides the radiated beam emitted by the laser beam source 26, which can include, for example, a beam expander for expanding the radiated beam, a scanner and an objective lens. Alternatively, an optical unit for processing is provided. Alternatively, the optical units of the irradiation units 22a and 22b can include a beam expander including a focusing lens and a scanner unit. Depending on the scanner unit, the focal position of the radiated beam in both the direction of the beam path and the plane perpendicular to the beam path can be modified and adapted. The scanner unit can be designed in the form of a galvanometer scanner, and the objective lens can be an fθ objective lens. In the embodiment of the device 10 shown in FIG. 1, the radiation beams 24a and 24b emitted by the irradiation units 22a and 22b are laser beams.

The device 10 further includes a melt pool monitoring system 28 for monitoring the melt pool generated by the interaction between the radiation beams 24a and 24b and the raw material powder. The melt pool monitoring system 28 includes an optical measuring device 30, and in the embodiment of the device 10 shown in FIG. 1, the optical measuring device is designed in the form of a high temperature detection device. The optical measuring device 30 is configured to receive and detect heat radiation. The thermal radiation can be electromagnetic radiation in the visible and / or infrared wavelength range, which has a maximum intensity of a unique wavelength depending on the temperature of the melt pool where the raw material powder is heated and melted. In response to the detected thermal radiation, the optical measuring device 30 outputs an intensity value indicating the detected radiation intensity.

Further, the apparatus 10 includes a layer control system 31 which is useful for monitoring the raw material powder layer 15 applied on the carrier 16 in order to detect defects or irregularities in the raw material powder layer 15. The layer control system 31 includes an optical measuring device 32. The optical measuring device is designed in the form of an image pickup device including a camera and an image processing system in the embodiment of the device 10 shown in FIG. The optical measuring device 32, particularly the camera of the optical measuring device 32, is configured to capture a two-dimensional image of the irradiation plane S. Further, the image processing system of the optical measuring device 32 is configured to automatically process a two-dimensional image of the upper surface of the raw material powder layer 15 in order to detect defects or irregularities. Alternatively, the image processing system can be omitted, and the image captured by the optical measuring device 32 can be visually inspected by the operator of the device 10.

In FIG. 2, FIGS. 2a, 2b and 2c are a schematic plan view, a schematic front view and a side surface of the scanning field plate 33 used for calibrating the irradiation units 22a and 22b and the first and second irradiation units 22a and 22b, respectively. It is a schematic diagram. The upper surface of the scanning field plate 33 defines a calibration irradiation plane C arranged at a predetermined distance from the beam radiation plane B. Similar to the irradiation plane S, the calibration irradiation plane C also has a first irradiation zone 18a that can be irradiated by the first irradiation unit 22a, a second irradiation zone 18b that can be irradiated by the second irradiation unit 22b, and the first and second irradiation units 22a. , 22b and an overlapping zone 18c that can be irradiated by both.

The first irradiation unit 22a of the irradiation system 20 is such that the offset of the first radiation beam 24a emitted by the first irradiation unit 22a in the calibration irradiation plane C with respect to the reference pattern does not exceed the threshold, for example, European Patent No. 3241668 (A1). ) Is calibrated as described in the specification (Patent Document 3). Further, the second irradiation unit 22b of the irradiation system 20 also has, for example, European Patent No. 3241668 so that the offset of the second radiation beam 24b emitted by the second irradiation unit 22a on the calibration irradiation plane C with respect to the reference pattern does not exceed the threshold value. It is calibrated as described in the specification (A1) (Patent Document 3).

After calibrating the first and second irradiation units 22a, 22b, the offset between the first and second radiation beams 24a, 24b in the overlapping zone 18 of the calibration irradiation plane C is negligible. That is, in the first and second irradiation units 22a and 22b, the incident point of the first radiation beam 24a in the overlap zone 18c of the designated calibration irradiation plane C is the second radiation beam 24b in the overlap zone 18c of the calibration irradiation plane C. It can be controlled by the control device 21 so as to coincide with the incident point of (FIGS. 2a to 2c).

As shown in FIGS. 2d and 2e, in order to manufacture a three-dimensional processed product during normal operation of the apparatus 10, the first and second radiation beams 24a and 24b emitted by the first and second irradiation units 22a and 22b. The powder layer 15 to be irradiated is coated on the carrier 16 by the powder coating device 14. As a result, the irradiation plane S of the raw material powder layer 15 that is defined by the surface of the raw material powder layer 15 and receives the radiation beams 24a and 24b emitted by the irradiation units 22a and 22b during the operation of the apparatus 10 is relative to the calibration irradiation plane C. It is substantially parallel and is located at a distance d from the calibration irradiation plane C. The distance d depends on the position of the leveling slider 17 of the powder coating device 14, particularly the powder coating device 14, with respect to the beam radiation plane B.

As shown in FIGS. 2d and 2e, the z-direction offset existing between the calibration irradiation plane C and the irradiation plane S inevitably causes the irradiation planes of the radiation beams 24a and 24b emitted by the irradiation units 22a and 22b. The x-direction and y-direction offsets dx _r and dy _{r in S} are generated. _{As is clear from FIG. 2d, the offset dx r} of the radiation beams 24a and 24b in the x direction in the irradiation plane S shifts the incident points of both the radiation beams 24a and 24b in the irradiation plane S by the same amount dx _r. , Not very important. On the other hand, the offset dy _r of the radiation beams 24a and 24b in the y direction in the irradiation plane S separates the incident points of the radiation beams 24a and 24b in the irradiation plane S from each other by 2 dy _{r in the y direction.}

A first test structure is used in the overlapping zone 18c of the irradiation plane S using a calibrated first irradiation unit 22a to correct the offset between the incident points of the radiation beams 24a, 24b emitted by the irradiation units 22a, 22b. Body 34 is manufactured. Further, the calibrated second irradiation unit 22b is used to manufacture the second test structure 36 in the overlapping zone 18c of the irradiation plane S. Various embodiments of the first and second test structures 34, 36 are shown in FIGS. 3-6. However, all the pairs of test structures 34 and 36 have in common that they are manufactured adjacent to each other in the same raw material powder layer.

_{In the next step, the offset dx t} , dy _t between the first and second test structures 34, 36 in the irradiation plane S is measured. After that, at least one of the first and second irradiation units 22a and 22b _{has a small offset dx t} and dy _t between the first and second test structures 34 and 36 in the irradiation plane S, and finally sets a threshold value. It is aligned based on _{the offset dx t} , dy _t measured between the first and second test structures 34, 36 in the irradiation plane S so as not to exceed.

Representative test structures 34, 36 shown in FIGS. 3-6 (described in more detail below) are offset dx _t , measured between the first and second test structures 34, 36 in the irradiation plane S. dy _t has a shape and arrangement such as may be used directly to align at least one of the first and second irradiation units 22a, 22b. _{In order to correct the measurement offsets dx t} , dy _t of the test structures 34, 36, only the first irradiation unit 22a is modified to shift the incident point of the first radiation beam 24a in the irradiation plane S, or the first irradiation unit 22a is modified. is second irradiation unit 22b corrects for shifting -dx _r and -dy _r incident point of the second radiation beam 24b in the irradiation plane S, or the first and second radiation beam 24a, the incident point of 24b aligned Both irradiation units 22a, 22b can be modified to allow this. For example, this may shift one of the irradiation units 22a, 22b by -dx _t , -dy _t , or both irradiation units 22a, 22b by an appropriate amount to correct the _{offset dx t} , dy _t. It is possible by shifting.

The first and second test structures 34 and 36 can be manufactured during the alignment operation of the device 10 which is performed separately from the normal operation of the device 10 for manufacturing the three-dimensional processed product. For example, the first and second test structures 34, 36 can be manufactured in the process of aligning the apparatus 10 performed after the completion of the modeling process and before the start of the new modeling process. However, it is also possible to manufacture the first and second test structures 34 and 36 during normal operation of the device 10. That is, the first and second test structures 34, 36 and the three-dimensional processed product can be manufactured simultaneously in a single modeling process.

The first and second test structures 34, 36 are in the form of massive components connected to the test structures 34, 36 and optionally a substrate plate placed on the carrier 16 to form a three-dimensional work piece on top. Can be manufactured at. When the test structures 34 and 36 are manufactured during the normal operation of the apparatus 10, the test structures 34 and 36 can be formed by the number of layers matching the number of layers of the three-dimensional processed product manufactured at the same time. _{Test structures 34, 36 in the form of massive components, for example, to measure the offset dx t} , dy _t between the first and second test structures 34, 36 after the modeling process is complete, for example, the micro shown in FIG. It can be measured with the help of a meter screw. _{To measure the offset dx t} , dy _t between the first and second test structures 34, 36, the test structures 34, 36 remain connected to the carrier 16 or substrate plate, or the carrier 16 Alternatively, it can be removed from the substrate plate. In order to improve the handling of the test structures 34 and 36 when removing the test structures 34 and 36 from the carry 16 and _{when measuring the offset dx t} and dy _{t between the test structures 34 and 36, the test structure 34} , 36 can be manufactured on a common base.

Alternatively, the first test structure 34 and the second test structure 36 can be manufactured in the form of a lost component formed separately from the substrate plate. In particular, the test structures 34, 36 manufactured in the form of lost components can be manufactured with fewer layers than the number of layers of the three-dimensional processed product manufactured at the same time. At least one layer of the first test structure 34 and the second test structure 36 can be arranged on the same plane as the intermediate layer of the simultaneously manufactured three-dimensional processed product formed at a predetermined distance from the carrier 16. Furthermore, it can be assumed that the layers of the test structure are manufactured regularly or randomly or according to an algorithm. For example, the layers of the five test structures can be manufactured in the same plane as the five processed product layers for every 20 processed product layers.

The offset dx _t , dy _t between the first and second test structures 34, 36 can be measured only after the production of the first and second test structures 34, 36 is completed. Alternatively or in addition, the offset dx _t , dy _t between the first and second test structures 34, 36 is, for example, the first and second test structures 34, 36 during the manufacture of the first and second test structures 34, 36. 2 Measurements can be made after the completion of one layer of test structures 34, 36 and before the start of production of additional layers of first and second test structures 34, 36.

In the apparatus 10 shown in FIG. 1, the offset dx _t , dy _t between the first and second test structures 34, 36 is with the help of the optical measuring device 30 of the melt pool monitoring system 28 and / or the layer control system 31. It can be measured with the help of the optical measuring device 32 of. The first and second test structures 34, 36 to measure _{the offset dx t} , dy _t between the first and second test structures 34, 36 with the help of the optical measuring device 30 of the melt pool monitoring system 28. After completion of one layer of, the region of the irradiation plane S containing the first and second test structures 34, 36 is scanned by the test radiation beam emitted by at least one of the first and second irradiation units 22a, 22b. Will be done. The region of the irradiation plane S scanned by the test radiation beam is expected to be where the first and second test structures 34, 36 manufactured by the first and second irradiation units 22a, 22b are perfectly aligned. In addition to the area, the surrounding area to be scanned includes the first and second test structures 34, 36 which are offset from each other due to the misalignment of the first and second irradiation units 22a, 22b. It is set to include the area.

In particular, the region of the irradiation plane S including the first and second test structures 34, 36 has a predetermined angle with respect to the first plurality of scan vectors and the first plurality of scan vectors extending in the irradiation plane S. Scanned with the test radiation beam according to a pattern containing a second plurality of scan vectors forming a right angle and extending into the irradiation plane S. The parallel scan vectors of the first and second plurality of scan vectors are unidirectional. Further, the region of the irradiation plane S including the first and second test structures 34 and 36 is the beam power of the first and second radiation beams 24a and 24b at the time of manufacturing the first and second test structures 34 and 36. And a test emission beam with a beam power and scan rate lower than the scan rate is scanned. Further, the region of the irradiation plane S including the first and second test structures 34 and 36 is irradiated in one direction.

When scanning the region of the irradiation plane S including the first and second test structures 34, 36, the test radiation beam and the first and second tests in the first and second test structures 34, 36 or the irradiation plane S The interaction with the raw material powder surrounding the structures 34, 36 is monitored by the optical measuring device 30. The intensity value detected by the optical measuring instrument 30 when the test emission beam is incident on the non-solidified raw material powder is the intensity detected by the optical measuring instrument 30 when the test emission beam is incident on the surface of the previously solidified test structure. Higher than the value. As a result, the location of the boundary between the first and second test structures 34, 36 and the raw material powder surrounding the first and second test structures 34, 36, and thus the first and second test structures 34, Offsets dx _t , dy _t between 36 can be measured.

When the optical measuring device 32 of the layer control system 31 _{is used to measure the offset dx t} , dy _t between the first and second test structures 34, 36, the first and second test structures 34, An image of the irradiation plane S after completion of one layer of 36, particularly a two-dimensional image, can be captured. The captured image can include the entire irradiation plane S or only the region of the irradiation plane S including the first and second test structures 34, 36. The location of the boundary between the first and second test structures 34, 36 and the raw material powder surrounding the first and second test structures 34, 36 is determined by automatic image processing or manually, i.e. visually inspecting the captured image. By doing so, the measurement can be performed based on the captured image of the irradiation plane S.

The irradiation units 22a and 22b are measured between the first and second test structures 34 and 36 so that the _{offset dx t} and dy _t do not exceed the threshold value after the production of the first and second test structures 34 and 36 is completed. It can be aligned based on the offsets dx _t and dy _t. Instead or in addition, _{of the first and second test structures 34, 36, so that the offset dx t} , dy _t does not exceed the threshold during the manufacture of the first and second test structures 34, 36. It can also be assumed that the irradiation units 22a and 22b are aligned based on the measurement offsets dx _t and dy _{t between them.} For example, the alignment procedure for aligning the irradiation units 22a, 22b is after the completion of one layer of the first and second test structures 34, 36, but after the first and second test structures 34, 36. It can be done before layer formation. _{Similar to the measurement of the offset dx t} , dy _t between the first and second test structures 34, 36, the alignment of the irradiation units 22a, 22b can be performed manually or automatically, for example, under the control of the control device 21. ..

Figures 3-6 show various typical designs of the test structure. As is clear from these figures, the design of the test structures 34, 36 is such that the first and second test structures 34, 36 are substantially parallel to the surface of the carrier 16 in the same raw material powder layer. Allow them to be adjacent to each other on the same plane. As a result, the first and second test structures 34 and 36 can be manufactured simultaneously and at a low molding height. Further, in various test structure designs according to FIGS. 3 to 6, when the first irradiation unit 22a and the second irradiation unit 22b are aligned, the first test structure 34 and the second test structure 36 are set to the second. It is common in that at least one edge of the one test structure 34 has a shape and arrangement that is aligned with at least one edge of the second test structure 36. _{In other words, the test structures 34 and 36 have offsets dx r} and dy _r between the radiation beams 24a and 24b emitted by the first and second irradiation units 22a and 22b when the irradiation units 22a and 22b are aligned. It has a shape and arrangement such that a _{corresponding offset dx t} , dy _t is generated between the edges of the first and second test structures 34, 36 extending in the same plane with respect to each other.

FIG. 3 shows a first embodiment of the test structure design. FIG. 3a shows the appearance of the test structure array manufactured by the aligned irradiation units 22a, 22b, and FIG. 3b shows the radiation beams 24a, 24b offsetting each other in both the x and y directions in the irradiation plane. The appearance of the test structure array produced by the emitting irradiation units 22a, 22b is shown. The test structure sequence contains two pairs of first and second test structures 34, 36. Both first test structures 34 have a rectangular shape and are manufactured and arranged adjacent to the second test structure 36 in the same raw material powder layer. The second test structure 36 also has a rectangular shape congruent with the rectangular shape of the first test structure 34. In each of the pairs of test structures 34, 36, the first and second test structures 34, 36 are arranged side by side.

In the first pair of test structures 34 and 36 shown on the left side in FIG. 3, the lower edge 38 of the first test structure 34 is the irradiation plane S when the first irradiation unit 22a and the second irradiation unit 22b are aligned. Within, parallel to the x direction and flush with the lower edge 40 of the second test structure 36 (FIG. 3a). On the other hand, when the first irradiation unit 22a and the second irradiation unit 22b are not aligned, the offset dy _t in the y direction in the irradiation plane S is the lower edge 38 and the second structure 36 of the first test structure 34. occurs between the lower edge 40 of which is the irradiation unit 22a, the radiation beam 24a emitted by 22b, it matches the offset dy _r between 24b.

In the second pair of test structures 34, 36 shown on the right side in FIG. 3 and rotated 90 ° with respect to the first pair of test structures 34, 36, the left edge 42 of the first test structure 34 is the first. When the first irradiation unit 22a and the second irradiation unit 22b are aligned, they are arranged in the irradiation plane S parallel to the y direction and on the same plane as the left edge 44 of the second test structure 36 (FIG. 3a). .. In contrast, when the first illumination unit 22a and the second irradiation unit 22b is not aligned, offset dx _t in the x direction within the irradiation plane S is the left edge 42 of the first test structure 34 second test structures 36 It occurs between the left edge 44 of the. This irradiation unit 22a, the radiation beam 24a emitted by 22b, matches the offset dx _r between 24b.

The test structure array according to FIG. 3 can be easily manufactured. Further, the offset between the test structures 34, 36 can be easily measured, for example, by a manual measuring tool or by optical measuring instruments 30, 32 as described above. However, when it is necessary to measure the offset in both the x direction and the y direction in the irradiation plane S, it is necessary to manufacture and measure two pairs of test structures 34 and 36.

Another test structure array is shown in FIG. FIG. 4a shows the appearance of the test structure array manufactured by the aligned irradiation units 22a, 22b, and FIG. 4b shows the radiation beams 24a, 24b offsetting each other in both the x and y directions within the irradiation plane S. The appearance of the test structure array manufactured by the irradiation units 22a, 22b that emits light is shown. Each of the first and second test structures 34, 36 is substantially linear. The first test structure 34 forms the upper left portion of the cross, and the second test structure 36 forms the lower right portion of the cross.

_{As is clear from FIG. 4b, the offset dx r} , dy _r between the radiation beams 24a, 24b emitted by the irradiation units 22a, 22b is _{the offset dx t} , dy _t between the test structures 34, 36. _{As it occurs, the offsets dx r} , dy _r of the radiation beams 24a, 24b in both directions within the irradiation plane S can be measured with the help of a single pair of test structures 34, 36. _{However, since manual measurement of offset dx t} , dy _t between linear test structures 34, 36 is not possible or at least very difficult, the test structure sequences according to FIG. 4 are the first and first. 2 It is particularly advantageous for the offset measurement process performed during the manufacture of the test structures 34, 36.

Another test structure sequence that is particularly suitable for use in the process for aligning more than two irradiation units, especially four irradiation units, is shown in FIG. FIG. 5a shows the appearance of a test structure array manufactured by the aligned irradiation unit, and FIG. 5b shows an irradiation unit that emits radiation beams that are offset from each other in both the x and y directions within the irradiation plane S. Shows the appearance of the test structure array manufactured by. The upper part of FIG. 5 shows the test structures 34 and 36 formed in the _{overlapping zone 18c 34} that can be irradiated by the third and fourth irradiation units. The central portion of FIG. 5 shows test structures 34, 36 formed in _{overlapping zones 18c 23} that can be irradiated by the second and third irradiation units. The lower part of FIG. 5 shows the test structures 34 and 36 formed in the _{overlapping portion 18c 12} that can be irradiated by the first and second irradiation units.

Each of the first test structures 34 was given to the corresponding substantially L-shaped second test structure 36 when the irradiation units used to manufacture the test structures 34, 36 were aligned. It has a rectangular shape that fits inside the cutout (Fig. 5a). In contrast, the offset between the radiation beams emitted by the irradiation unit used to manufacture the test structures 34, 36 respectively results in an offset between the test structures 34, 36 (FIG. 5b). .. _{Therefore, by measuring the offsets dx t43} and dy _t43 of the test structures 34 and 36 shown in the upper part of FIG. 5b, the third and fourth irradiation units in both the x direction and the y direction in the irradiation plane S It is possible to measure the offset between the emitted emitted beams. _Emitted by the second and third irradiation units in both the x and y directions within the irradiation plane S by measuring _{the offsets dx t32} , dy t32 of the test structures 34, 36 shown in the central portion of FIG. 5b. It is possible to measure the offset between the emitted beams. _{Further, by measuring the offsets dx t12} and dy _t12 of the test structures 34 and 36 shown in the lower part of FIG. 5b, the first and second irradiation units in both the x direction and the y direction in the irradiation plane S can be used. It is possible to measure the offset between the emitted emitted beams.

The first and second test structures 34, 36 can be arranged so as to be in contact with each other as shown in FIG. However, as shown in FIG. 6, it can be assumed that the first and second test structures 34 and 36 are arranged at a predetermined distance from each other. FIG. 6a shows the appearance of a test structure array manufactured by the aligned irradiation unit, and FIG. 6b shows an irradiation unit that emits a radiation beam that is offset from each other in both the x and y directions within the irradiation plane S. Shows the appearance of the test structure array manufactured by. The arrangement according to FIG. 6 minimizes the risk of double irradiation of the raw material powder region due to the misalignment of the irradiation units used in the manufacture of test structures 34, 36.

As shown in FIG. 7, the test structures 34, 36 can be measured with the help of, for example, a micrometer screw. As shown in FIG. 7a, in the first step, the set extension in the x direction can be measured by measuring the dimension of the solid (upper in FIG. 7) portion of the second test structure 36 in the x direction. .. In the second step, the dimensions of the combination of the first and second test structures 34, 36 in the x direction can be measured as shown in FIG. 7b to measure the actual dimensions in the x direction. _{The offset dx t} between the first and second test structures 34, 36 is by forming a difference between the set dimension in the x direction measured according to FIG. 7a and the actual dimension in the x direction measured according to FIG. 7b. Can be measured. Measurement of the offset dy _t between the first and second test structures 34, 36 in the y direction can be carried out in the same manner.

In order to align the four irradiation units based on the offset measurement using the test structure array according to FIG. 5, in the first step, the third irradiation unit is, for example, the irradiation beam emitted by the first irradiation unit. the third illumination units to shift by _{-dx r32} and _{-dy r32} by shifting _{-dx t32} and _{-dy t32,} can be aligned in order to correct the measurement offset _{dx t32, dy} t32. _{The first irradiation unit is shifted by -dx t12} and -dy _t12 in order to shift the radiation beam emitted by the first irradiation unit by -dx _r12 and -dy _r12 . Thereafter, fourth irradiation unit, taking into account the previous shift of the third illumination unit, the radiation beam emitted by the fourth radiation unit only _(-dx t43 -dx _t32) and _(dy t43 _{-dy t32)} Shift In order to do so, it is shifted by _{(-dx t43-} dx t32) and (dy _{t43- dy t32).} The position of the second irradiation unit is maintained constant. Therefore, the second irradiation unit is used as a kind of reference irradiation unit. However, it can be assumed that another irradiation unit, for example, a third irradiation unit is used as a fixed position reference irradiation unit.

After the irradiation units 22a and 22b are aligned, a plurality of raw material powders are maintained while maintaining a constant distance D between the beam radiation plane B and the irradiation plane D in order to manufacture a three-dimensional processed product during normal operation of the device 10. Layer 15 is applied onto the carrier 16 and irradiated with the first and second irradiation beams 24a, 24b emitted by the calibrated and aligned first and second irradiation units 22a, 22b. As a result, the calibration and alignment of the irradiation units 22a and 22b are maintained, and the continuous high quality of the three-dimensional processed product is obtained. The distance D between the beam emission plane B and the irradiation plane S must be maintained constant not only during the production of a single processed product but also during the subsequent processed product manufacturing process. As a result, additional calibration and / or alignment steps during the subsequent work piece manufacturing process can be omitted.

In order to maintain a constant distance D between the beam radiation plane B and the irradiation plane S, the leveling slider 17 of the powder coating equipment 14, especially the powder coating equipment 14, is appropriately positioned with respect to the beam radiation plane B by the positioning tool 27. Will be done. In particular, the positioning tool 27 is used to position the powder coating device 14 so that the constant distance D between the beam emission plane B and the irradiation plane S is maintained even after the leveling slider 17 is replaced.

Claims (22)

A method of arranging a multi-beam irradiation system (20) for use in an apparatus (10) for manufacturing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic or particle radiation. ,
i) A step of applying the first raw material powder layer on the carrier (16) so as to define the irradiation plane (S) to be irradiated by the radiation beams (24a, 24b) emitted by the irradiation system (20). ,
ii) The first raw material in the overlapping zone (18c) of the irradiation plane (S) using the first radiation beam (24a) emitted by the calibrated first irradiation unit (22a) of the irradiation system (20). Steps to manufacture the first test structure (34) in the powder layer,
iii) The first in the overlapping zone (18c) of the irradiation plane (S) using the second radiation beam (24b) emitted by the calibrated second irradiation unit (22b) of the irradiation system (20). The step of manufacturing the second test structure (36) on the raw material powder layer,
iv) A step of measuring _{the offset (dx t} , dy _t ) between the first and second test structures (34, 36) in the irradiation plane (S).
v) The first and second configurations based on the _{measurement offsets (dx t} , dy _t ) between the first and second test structures (34, 36) so that the offset does not exceed the threshold. With the step of aligning at least one of the completed irradiation units (22a, 22b),
Including methods. Step i), and at least one of steps ii) and iii) to manufacture at least one of the multilayer first test structure (34) and the multilayer second test structure (36), step iv) and The method according to claim 1, which is repeated before executing v). The method according to claim 1 or 2, wherein a plurality of first test structures (34) and a plurality of second test structures (36) are manufactured. The first test structure (34) and the second test structure (36)
-At the time of alignment operation of the device (10), which is performed separately from the normal operation of the device (10) for manufacturing the three-dimensional processed product, and / or-the device for manufacturing the three-dimensional processed product. During normal operation of (10)
Manufactured,
The method according to any one of claims 1 to 3. The first test structure (34) and the second test structure (36)
-Especially in the form of massive components containing a number of layers that match the number of layers of the 3D work piece, especially connected to the substrate and / or especially simultaneously produced, or-especially the layers of the 3D work piece manufactured at the same time. In the form of a lost component formed separately from the substrate plate containing a number of layers less than the number of
Manufactured,
The method according to any one of claims 1 to 4. When the first test structure (34) and the second test structure (36) are manufactured in the form of a lost component, the first test structure (34) and the second test structure (36) The method according to claim 5, wherein at least one layer of the above is arranged in the same plane as an intermediate layer of the three-dimensional processed product formed at a predetermined distance from the carrier (16). _{The offset (dx t} , dy _t ) between the first and second test structures (34, 36) is
-After the completion of the manufacture of the first and second test structures (34, 36) and / or-at the time of the manufacture of the first and second test structures (34, 36).
Measured,
The method according to any one of claims 1 to 6. _{The offset (dx t} , dy _t ) between the first and second test structures (34, 36) is measured by an optical measuring instrument (30, 32), and the optical measuring instrument (30) particularly melts. The method according to any one of claims 1 to 7, wherein one component of the pool monitoring system (28) or one component of the layer control system (3) is formed. 8. The eighth aspect of the invention, wherein the optical measuring device (30) is designed in the form of a high temperature detection device configured to detect heat radiation and output an intensity value indicating the intensity of the detected heat radiation. the method of. _{Measuring the offset (dx t} , dy _t ) between the first and second test structures (34, 36) can be done.
-After completion of the layers of the first and second test structures (34, 36), the first with a test radiation beam emitted by at least one of the first and second irradiation units (22a, 22b). And scanning the region of the irradiation plane (S) including the second test structure (34, 36).
-The raw material powder surrounding the test radiation beam and the first and second test structures (34, 36) or the first and second test structures (34, 36) by the optical measuring instrument (30). To monitor the interaction with
-Based on the interaction between the test radiation beam and the raw material powder surrounding the first and second test structures (34, 36) and the first and second test structures (34, 36). To measure the location of the boundary between the first and second test structures (34, 36) and the raw material powder surrounding the first and second test structures (34, 36).
including,
The method according to claim 8 or 9. A plurality of first scan vectors in which the region of the irradiation plane (S) including the first and second test structures (34, 36) extends in the irradiation plane (S), and the first scan vector. 10. The test radiation beam is scanned according to a pattern including a second plurality of scan vectors extending in the irradiation plane (S) at a predetermined angle, particularly at right angles to the plurality of scan vectors. The method described in. 11. The method of claim 11, wherein the parallel scan vectors of the first and / or second plurality of scan vectors are unidirectional. The region of the irradiation plane (S) including the first and second test structures (34, 36) is the first at the time of manufacturing the first and second test structures (34, 36). And / or any one of claims 10-12, which is scanned by the test radiation beam having a beam power and / or a scan speed lower than the beam power and / or scan speed of the second radiation beam (24a, 24b). The method described in. _{Measuring the offset (dx t} , dy _t ) between the first and second test structures (34, 36) can be done.
-After the completion of the layers of the first and second test structures (34, 36), capturing an image of the irradiation plane (S), especially a two-dimensional image,
-Based on the captured image of the irradiation plane (S), the first and second test structures and the raw material powder surrounding the first and second test structures (34, 36). Measuring the location of the border between
including,
The method according to any one of claims 9 to 13. At least one of the first and second calibrated irradiation units (22a, 22b)
-After the completion of the manufacture of the first and second test structures (34, 36) and / or-at the time of the manufacture of the first and second test structures (34, 36).
Aligned based on the _{measured offset (dx t} , dy _t ) between the first and second test structures (34, 36) so that the offset does not exceed the threshold.
The method according to any one of claims 1 to 14. When the first test structure (34) and the second test structure (36) are aligned with the first irradiation unit (22a) and the second irradiation unit (22b), the first test structure (34) ) Is manufactured to have a shape and arrangement that is aligned with at least one edge (40, 44) of the second test structure (36). Item 2. The method according to any one of Items 1 to 15. The invention according to any one of claims 1 to 16, wherein the first test structure (34) has a rectangular shape and is manufactured adjacent to a second test structure (36) having a rectangular shape as well. the method of. The first and second test structures (34, 36) are substantially linear and form a cross when the first irradiation unit (22a) and the second irradiation unit (22b) are aligned. , The method according to any one of claims 1 to 17. The first test structure (34) is substantially L-shaped when the first irradiation unit (22a) and the second irradiation unit (22b) are aligned. The method of any one of claims 1-17, which has a rectangular shape that fits within the cutout given to. The method according to any one of claims 1 to 19, wherein the first and second test structures (34, 36) are manufactured on a common base. A method of operating an apparatus (10) for manufacturing a three-dimensional processed product by irradiating a layer of raw material powder with electromagnetic or particle radiation, which comprises a multi-beam irradiation system (20).
-A step of aligning the multi-beam irradiation system (20) according to the method according to any one of claims 1 to 20.
-A further raw material powder layer on the carrier (16) to produce a three-dimensional processed product while maintaining a constant distance (D) between the beam radiation plane (B) and the irradiation plane (S). And irradiate the raw material powder layer with the first and second irradiation beams (24a, 24b) emitted by the calibrated and aligned first and second irradiation units (22a, 22b). When,
Including methods. A powder coating device configured to coat a raw material powder layer on the carrier (16) in order to maintain a constant distance (D) between the beam radiation plane (B) and the irradiation plane (S). (14) is appropriately positioned with respect to the beam radiation plane (B), and the positioning of the powder coating device (14) is particularly accurate to ± 2 μm, preferably ± 1 μm. The method according to claim 21, which is carried out by a positioning tool (27) configured to be able to position the powder coating device (14) with respect to the above.

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