DE102017212565A1 - Method for producing a coherent surface area, irradiation device and processing machine - Google Patents

Abstract

A method for producing a contiguous surface area (2) of a three-dimensional component by irradiation of a powder layer (3), comprising: splitting a primary processing beam (4) onto at least two processing beams (4a, b), guiding the at least two processing beams (4a, b) to a common scanner device (5) for aligning the at least two processing beams (4a, b) on different positions (P1, P2) in a processing plane (E) of the scanner device (5) with the contiguous surface area (2), wherein generating the contiguous Surface region (2) comprises: simultaneously changing the positions (P1, P2) of the at least two processing beams (4a, b) in a subregion or in at least two different subregions (T3, T4) of the contiguous surface region (2) until the powder layer (3 ) is completely melted in the partial area or in the at least two partial areas (T3, T4), as well as simultaneously changing the positions (P1, P2) of the at least two machining beams (4a, b) or of at least two further machining beams in a further subarea or in at least two different further subregions (T5, T6) of the contiguous surface area (2) until the powder layer (3) is completely melted in the further subarea or in the at least two further subregions (T5, T6).

Description

The present invention relates to a method for producing a contiguous area of a three-dimensional component by irradiating a powder layer with at least two processing beams, in particular by means of at least two laser beams. The invention also relates to an irradiation device for a processing machine for producing three-dimensional components by irradiation of powder layers, comprising: a beam splitting device for splitting a primary processing beam, in particular a laser beam, at least two processing beams, in particular at least two laser beams, and a scanner device for aligning the at least two processing beams to different positions in a processing plane of the scanner device, and a processing machine with such an irradiation device.

Three-dimensional components can be produced by so-called additive manufacturing processes (also referred to as additive manufacturing processes). In such methods, the three-dimensional component is generated in layers or in layers. In so-called selective laser melting or laser sintering (also referred to as laser metal fusion, LMF), a powder material is locally melted by a high-energy machining beam, in particular a laser beam, in order to produce a layer of the three-dimensional component. The high-energy processing beam, for example in the form of the laser beam, can have a power of the order of several hundred watts.

To increase the efficiency or the build-up rate in the production of three-dimensional components, it is known to use two or more processing beams, in particular two or more laser beams, which are generated by a corresponding number of beam sources and via separate scanner devices on a (common ) Editing area are aligned. Due to space constraints, only a limited number of steel deflection devices, for example in the form of scanner optics, can be accommodated in a processing machine or in an irradiation device. Nevertheless, in order to achieve the most efficient (fast) exposure possible, a (primary) processing beam can be split into two or more processing beams by means of a beam splitting device.

In the WO 2015/191257 A1 For example, a method and apparatus for selective laser melting are described in which multiple laser beams are used simultaneously to increase component manufacturing efficiency. In the method, a plurality of laser beams are directed to a single galvanometer to produce a corresponding plurality of three-dimensional structures or components in a powder bed. The plurality of laser beams can be generated by dividing a primary laser beam into the plurality of laser beams. Each one of the plurality of laser beams can be automatically dynamically focused before being directed to the galvanometer.

For the efficient production of a three-dimensional component, it is from the WO 2016/128430 A1 It is known to use an irradiation device with a beam shaping device for shaping the beam profile of the laser beam, in which the length and / or the width of the beam profile in the machining field can be changed. For additional shaping of the beam profile, the beam shaping unit can have at least one further optical element, which can be designed, for example, as a diffractive optical element. The diffractive optical element can serve to generate the high energy beams which strike the processing field from a single high energy beam. The further optical element can also be designed as a wedge-shaped optical element which covers only a part of the beam profile in order to spatially separate one or more profile regions of the beam profile from other profile regions of the beam profile.

The EP 2 875 897 B1 describes a method for controlling an irradiation system comprising a plurality of irradiation units. In the method, for example, checkerboard-like irradiation patterns or line-shaped or stripe-shaped irradiation patterns are used for producing a contiguous area.

Object of the invention

The invention has for its object to provide a method of the type mentioned above and an irradiation device and a processing machine with such an irradiation device, with which an efficient production of contiguous surface areas of a three-dimensional component is possible.

Subject of the invention

This object is achieved according to a first aspect by a method of the aforementioned type, comprising: splitting a primary processing beam on the at least two processing beams, guiding the at least two processing beams to a common scanner device for aligning the at least two Processing beams to different positions in a processing plane of the scanner device, in which the contiguous area is located, wherein the generation of the continuous surface area, which is divided for the irradiation in a plurality of preferably rhomboid (ie parallelogram), in particular diamond-shaped, rectangular or square sections, comprising: simultaneously changing the positions of the at least two processing jets in a subarea or in at least two different subregions of the contiguous surface area until the powder layer in the subarea or in the at least two subareas is completely melted, and simultaneously changing the positions of the at least two processing jets or at least two further processing beams in a further partial area or in at least two different further partial areas of the connected façade Henbereichs until the powder layer is completely melted in the other part or in the at least two other sub-areas.

The method enables a speed increase in the exposure of comparatively large contiguous areas by dividing the power of the primary processing beam into the two or more processing beams. In contrast to that in the WO 2015/191257 A1 described method, the division into several processing beams is thus not used to produce a plurality of identical, spatially separated components, but to produce a contiguous area of a layer of one and the same component.

The two or more processing beams are approximately parallel to each other (typically at a small angle) and are transmitted through the same beam splitter, i. via the same or the same (scanner) mirror, aligned to the working plane. The (focused) processing beams strike different (focus) positions in the working plane, the distance between the (focus) positions typically being comparatively small, for example less than about 1.0 mm. The difference angle between the two processing beams deflected at the scanner device is typically comparatively low and is generally less than approximately 1 °.

In the method, a contiguous surface area of the three-dimensional component is produced or exposed by dividing it into a plurality of partial areas (for example in a preceding method step). The plurality of subregions typically forms a regular, grid-shaped arrangement, for example in the manner of a chess board, which covers the contiguous surface area. The subregions ideally do not overlap and ideally adjoin one another directly. Since the angles at which the machining jets hit the powder layer vary depending on the position in the machining area, it may possibly lead to an (unwanted) partial overlapping of adjacent subareas of an order of magnitude, generally about 10% of the respective edge length (Length or width) of the sections come.

The positions of the two processing beams may be in different subareas, so that two or more subareas are exposed simultaneously by the simultaneous change of the positions of the at least two processing beams. However, the positions of the two or more processing beams may also be in one and the same subarea, which can be melted faster due to the use of two or more processing jets than when using a single processing beam. The other sub-area (s) which are subsequently exposed or simultaneously illuminated by means of further processing beams typically does not immediately adjoin the sub-area (s) exposed in the preceding step, as this is not ideal for the heat balance of the molten powder material. Therefore, between the steps of melting of the partial regions and the subsequent melting of the further partial regions or regions, a change in the alignment of the processing beams in the processing plane by means of the scanner device can be made, in which the processing beams are not activated. After the alignment has been changed, the processing beams are switched on again in order to expose the further partial area (s).

In one variant, the contiguous surface area is surrounded by an edge contour of a layer of the three-dimensional component, the edge contour and / or an edge region formed between the edge contour and the contiguous surface area being combined with the primary processing beam, in particular with the primary laser beam, or with another processing beam, especially with a further laser beam is irradiated. As a rule, the edge contour of the layer of the three-dimensional component to be produced does not coincide with the edge contour of the contiguous surface region, so that an edge region remains between the edge contour and the contiguous surface region. The edge region typically has a geometry or an area into which no partial region of the continuous surface area fits more. The border area therefore becomes typical irradiated or melted with a single processing beam. For this purpose, the primary processing beam can be used, which in this case is not split into a plurality of processing beams, or another processing beam can be used which is generated by a further beam source and / or which is aligned with the processing plane via another scanner device , If the primary processing beam is used, it is favorable if a dynamic as possible, fast switching between the multiple processing beams and the primary processing beam can be done. For this purpose, a beam splitter device can be provided which can be moved quickly into and out of the beam path of the primary processing beam. The use of a single, non-split machining beam is also beneficial in exposing the edge contour of the layer of the two-dimensional component.

In a further variant, the different positions of the processing beams in the subarea or in the at least two subareas in the processing plane are offset from one another in a first direction and the simultaneous changing of the positions of the at least two processing beams in the subarea or in the at least two subareas comprises a simultaneous one Moving the processing beams in a second, preferably to the first vertical direction in the working plane. The outer contours of the partial regions in this case typically run parallel to the first or the second direction. The processing beams in this case are typically moved with a scanning motion in a typically straight line along the extent of the respective portion in the second direction. At the edge of the respective partial region, a reversal of motion takes place with a (small) lateral offset in the first direction, before the processing rays in the first direction are moved in opposite directions over the entire width of the respective partial region. In the event that several processing jets are positioned in the same sub-area, it may optionally -. with a suitable dimensioning of the partial area - sufficient if the processing beams are moved only once in the second direction over the partial area in order to completely melt it.

In a further variant, a gas stream is passed over the powder layer, the flow direction is preferably at least partially directed against the direction of movement of the processing beams in the working plane and / or preferably the order of irradiation of the sub-regions depending on the distance of the respective sub-areas in the flow direction of a supply device to provide the gas stream. The gas stream may, for example, be a protective gas stream in order to protect optical components of the irradiation device, for example a window, from contamination, for example from soot particles, which form during the irradiation of the powder material. It has proved to be advantageous if the movement, more precisely the direction of movement, of the processing beams during the exposure does not coincide with the flow direction of the protective gas flow, since soot particles are removed by the protective gas flow, in this case directly before or before the processing beams the irradiated powder layer would be stored and welded.

To counteract this problem, the subregions may be irradiated in an order in which the or the part region (s) furthest away from the provision device in the flow direction of the gas stream are first irradiated. In this case, it is preferably taken into account that two partial regions lying directly next to one another are generally not irradiated directly in succession. In particular, the directions of movement of the processing beams in each irradiated subarea in the processing plane occupy the respective same angle with respect to the flow direction of the gas flow.

In the event that the second direction along which the exposure takes place is parallel or approximately parallel to the protective gas flow, the movement of the processing beams along the second direction, for example the Y direction, can only take place with one orientation (positive or negative Y direction ) respectively. For example, in the case that the flow direction of the protective gas stream in the negative Y-direction, the processing beams can be moved only in the positive Y-direction, as for example in the WO 2014/125280 A1 described in detail, which is incorporated herein by reference.

In a further variant, the positions of the at least two processing beams in the first direction are at a distance from one another, which substantially corresponds to an integral multiple of the extension of a respective subarea in the first direction (typically different from one). As has been described above, it has proved to be advantageous if, during the exposure of a contiguous surface area, the required laser power is introduced in the form of closed rhomboid, for example diamond-shaped, square or rectangular sections. Although the parallel exposure of two immediately adjacent subareas has turned out to be rather unfavorable with regard to the heat balance of the melt, it is known from US Pat certain cases also possible or useful. For the parallel irradiation of two partial regions, it has proved to be advantageous if a gap of at least one partial region is formed between the partial regions irradiated simultaneously with the two or more treatment beams. Before the irradiation of the further partial regions which form the gaps between the irradiated partial regions, further partial regions of the continuous surface region are generally irradiated, which are also offset in the second direction to the already irradiated partial regions. Ideally, the distance of the positions of the processing beams from one another corresponds exactly to an integer multiple, in particular an even integer multiple, for example exactly twice or exactly four times, but possibly also a non-even multiple, for example three times, five times. .. the extension of a respective subarea. As has been described above, depending on the position of the processing beams in the working plane in the first direction, undesired partial overlapping of the portions may occur. For the purposes of this application, a distance which substantially corresponds to an integer multiple of the extent of a respective subarea in the first direction is understood to be a distance which is +/- 10% of the extension (edge length) of a respective subarea in the first direction differs.

The geometry or the area of the respective subregions, which form the contiguous surface area, is generally the same size. But it is also possible that the contiguous surface area has several types of, for example, rectangular portions which differ in their surface area, for example in their width and / or in their length. In this case, the lengths and / or the widths of the respective partial regions can each have an integral relationship with one another, such that two or more of the partial regions complement each other to form a larger partial region. The use of smaller subareas may be advantageous, in particular, at the edge of the contiguous surface area in order to adapt it as well as possible to the surrounding edge contour.

In a further variant, a difference angle between the at least two processing beams in the first direction when aligning the at least two processing beams to different positions in the working plane whose distance in the working plane varies depending on a deflection angle of the scanner device depending on location selected such that either adjacent portions adjacent to each other in the middle of the processing area in the first direction or adjoin adjacent portions at the edge of the processing area in the first direction to each other. In order to align the two processing beams to different positions in the working plane, it is necessary that they emerge at a (slightly) different angle from the scanner device, which is measured in a deflection plane that runs along the first direction.

In the middle of the machining area, one of the machining jets is aligned perpendicular to the working plane, which corresponds to a deflection angle of 0 °. At the edge of the processing area, one of the processing beams is aligned at a deflection angle of, for example, approximately 20 °, which corresponds to the maximum possible deflection angle through the scanner device. During the deflection of, for example, two processing beams, there is a change in the distance between the (focus) positions of the two processing beams as a function of the deflection angle and thus of the positions of the processing beams in the processing plane in the first direction. The distance or the offset between the (focus) positions and thus between the two simultaneously irradiated portions is greater, the further the processing beams are pivoted in the deflection plane in the direction of the edge of the processing area. At a fixed differential angle between the two machining beams, the offset dimension or the distance between the two machining beams can be set at the edge of the machining area such that two adjacent subregions contact each other after the exposure or adjoin one another directly. Upon pivoting inward, the overlap factor between adjacent exposed portions increases continuously, i. two adjacent subregions and also the single webs overlap more in the middle of the processing area than at the edge of the processing area. In the irradiation process, this means a reduction of the effectiveness toward the center of the processing area, since the trailing processing beam deflected at a larger deflection angle exposes a part of an already exposed portion a second time, i. that the two subareas partially overlap in the middle of the processing area (usually by no more than about 10% of the respective extent of the subareas). As has been shown above, typically two adjacent partial regions are not irradiated simultaneously, but instead there is a gap of at least one partial region between the irradiated partial regions. The difference angle is therefore typically selected such that a corresponding gap remains between the two simultaneously irradiated partial regions, which corresponds exactly to the width of one (or possibly several) partial regions in the middle of the processing region.

Alternatively, the differential angle can be adjusted such that in the zero position, ie in the middle of the machining area, there is no lateral offset between adjacent partial areas in the first direction, ie they directly adjoin one another in the middle of the machining area. This lateral offset or distance increases during pivoting of the two processing beams with increasing deflection angle and can be selected so that two adjacent portions are marginally spaced apart at the edge of the processing area. In this case, it can be utilized that the actual (focus) positions of the processing beams in the entire processing area can be measured by a suitable online calibration and are thus known. The variable offset dimension or the distance between in each case two of the exposed partial regions in the first direction at the edge or in the vicinity of the edge of the processing region is therefore likewise known and can be parallel to the production of the partial regions with a further processing beam or subsequently with a single processing beam For example, with the primary processing beam, be exposed to form the contiguous area.

Optionally, the differential angle or the difference angles between the at least two processing beams which serve for the exposure of different partial areas can be varied depending on the deflection angles or on the position of the (focus) positions in the first direction in the processing area. For this purpose, for example, a (fast) beam splitting device can be used for splitting the primary machining beam into the at least two machining beams, which makes it possible to adjust the differential angle. For this purpose, the beam splitter device may, for example, have differently designed beam splitter elements, which may optionally be introduced into the beam path of the primary machining beam, for example wedge plates with different wedge angles (see above).

As an alternative to varying the difference angle, a preferably telecentric F-theta objective can be used to focus the processing beams (as well as possibly further processing beams) in the processing plane. When using a telecentric lens, the processing beams are always aligned perpendicular to the processing plane, so that almost no location-dependent variation of the distance of the processing beams occurs in the processing plane.

In a further variant, the positions of the processing beams or of the further processing beams in the further subarea or in the at least two further subareas are offset from one another in a second direction and the positions of the at least two processing beams or the at least two further processing beams in the further subarea are changed simultaneously or in the at least two further subregions comprises a simultaneous movement of the processing beams or the further processing beams in a first, preferably to the second vertical direction. It may be favorable if some (first) partial areas are scanned along the first direction, while further (second) partial areas are possibly scanned simultaneously along a second, perpendicular to the first direction.

For example, in a contiguous area which is divided into rhomboidal, such as diamond-shaped, square, or rectangular areas in the manner of a chessboard, the "white" areas may be scanned in the first direction while the "black" areas are scanned in the second direction , or the other way around. For this purpose, one and the same primary machining beam can be divided first in the first direction and subsequently in the second direction with the aid of two different beam splitting devices, which can optionally be introduced into the beam path. Optionally, one and the same beam splitter device can be used for this purpose, which is rotated by 90 ° about an axis of rotation which runs along the beam direction of the primary machining beam. For example, a beam splitter device in the form of a diffractive optical element can be used for the division of the primary processing beam or of the further primary processing beam into a plurality of partial beams.

In a development, the method additionally comprises: splitting a further primary machining beam onto the at least two further machining beams, and guiding the at least two further machining beams to a further common scanner device for aligning the at least two further machining beams to different positions in the machining plane. For the irradiation of the further partial areas, a further primary processing beam can be used, which is divided into two or more, for example five or more, further processing beams. As described above, the further processing beams may be used to irradiate the "black" portions scanned in the second direction while the processing beams into which the primary processing beam is split may be used to irradiate the "white" portions , or the other way around. In particular, in this case, it has proven to be advantageous if the two or more machining jets are used simultaneously to irradiate one and the same subarea, for example by moving two or more parallel machining jets over the entire width of the respective subarea before a reversal of direction takes place and the two or more processing beams are moved in opposite directions.

In this variant too, a (non-split) machining beam can be used to process those areas of a layer of the three-dimensional component which are unsuitable for the irradiation by the divided machining beams. This can be, for example, the (edge) contour (s) of the layer of the three-dimensional component or the edge region between the contiguous surface region and the edge contour or basically all regions that are too narrow or too bulky for the irradiation with two or more processing beams moved in parallel across the working plane.

In another variant, a focus position correction for correcting the focus positions of the processing beams in the beam path of the primary processing beam is made. The focus positions of the at least two processing beams along their respective beam direction should ideally be in the working plane. Due to the deflection by means of the scanner mirrors (without the use of an F-theta objective), the focus positions of the processing beams upon pivoting of the scanner mirror (s) lie on a spherical surface, i. not exactly in the working plane. In order to compensate for the variation of the focus position (perpendicular to the working plane) over the machining area, a focus position correction can be made which corrects the spherical aberration of the scanner field, for example by rapid compensating movements of a lens arranged in the beam path of the primary machining beam Beam direction of the primary processing beam is shifted, which has a rapid focus position shift result. The movable or displaceable lens can be arranged, for example, in a focus position correction device or optics. Due to the comparatively small difference angle between the processing beams, it is sufficient to make the focus position correction for the primary processing beam, i. It is possible to dispense with an individual focus position correction of each individual of the processing beams.

Control technology can be used for the focus position correction or, in general, the center of gravity of the positions of the machining beams in the working plane for the path control, i. the mean value is used as the movement path of the (primary) machining beam. The control in this case may be (essentially) done in such a way as if only the primary processing beam were used for the irradiation. In particular, the centroid trajectory can be used as a default for determining the focus position correction.

The invention also relates to an irradiation device of the type mentioned above, which has a control device which is formed or programmed, the positions of the at least two processing beams in a subarea or in at least two subregions of a contiguous surface area, for the irradiation in a plurality of preferably rhomboid, in particular diamond-shaped, rectangular or square sections is divided, simultaneously to change until the powder layer is completely melted in the subregion or in the at least two sub-areas, and which is formed, the positions of the at least two processing beams or at least two further processing beams in a further subsection or in at least two different further subregions of the contiguous surface area to be changed simultaneously until the powder layer in the further subarea or in the at least two white is completely melted down in certain areas.

The control device is thus designed or programmed to carry out the method described above for generating the contiguous surface area. Accordingly, the control device may also be designed or programmed to execute the variants of the method described above. The control device acts on the scanner device for the simultaneous change of the positions of the (further) processing beams, more precisely on the or on the two scanner mirrors of the scanner device.

In one embodiment, the irradiation device has a further beam splitting device for splitting a further primary processing beam, in particular a further laser beam, at least two further processing beams, in particular at least two further laser beams, and a further scanner device for aligning the at least two further processing beams to different positions in the Machining level.

By way of example, the irradiation device can have two identically constructed scanner devices, which are arranged such that their scan regions or their processing fields are in overlap the working plane. By means of the further processing beams, for example, in the manner described above, the "black" or the "white" portions of a checkerboard-like contiguous area can be irradiated. As has been described above, such a checkerboard-like surface area does not necessarily have to have quadratic subareas, but rather may have, for example, rhomboid, in particular diamond-shaped, rectangular or square subareas. In particular, the further beam splitting device may be configured to divide the further primary machining beam in the second direction so that the further machining beams are aligned to different positions in the machining plane in the second direction while the beam splitting device is configured to divide the primary machining beam in a first direction , so that the processing beams are aligned at different positions in the first, preferably to the second vertical direction.

In one embodiment, the beam splitter device for splitting the primary processing beam onto the at least two processing beams is formed by splitting a beam cross section of the primary processing beam. In this case, the beam splitting is thus not carried out by a polarization beam splitter, in which the entire beam cross section is usually divided into two mutually perpendicular polarization components. The division of the primary machining beam onto the at least two machining beams has proven to be advantageous, in particular in the collimated beam path of the primary machining beam, so that the beam splitter device is preferably arranged in the collimated beam path of the primary machining beam. For the division of the beam cross-section, it is advantageous if the processing beams generated by the splitting are each aligned at an angle to each other, which typically remains in the deflection of the processing beams on the scanner device. As an alternative or in addition, it is also possible to displace the processing beams laterally relative to each other during the division at the beam splitter device.

In a development, the beam splitter device is designed to divide the primary processing beam by deflecting at least a portion of the beam cross section of the primary processing beam (preferably at a differential angle to the beam direction of the primary processing beam). In this case, for example, the beam splitter device can serve to divert half of the beam cross-section-and thus half the power-of the processing beam by the beam splitter device covering only one half of the beam profile.

In a further development, the beam splitter device is designed as a wedge plate transparent to the primary processing beam. The wedge plate can serve for deflecting a portion of the beam cross section at a Differenzkwinkel, which is usually maintained up to the working plane. Due to the wedge angle of the wedge plate, for a given refractive index of the transparent material of the wedge plate, e.g. Quartz glass, the difference angle set. In particular, the wedge angle can be determined such that the distance of the positions of the at least two machining beams in the machining plane corresponds to an integral multiple of the edge length of an irradiated partial area. The wedge angle is preferably set such that the distance between the positions corresponds to twice or three times the edge length of a respective partial area in the first direction, so that a gap of one or two partial areas remains between the simultaneously irradiated partial areas during the irradiation. The wedge plate is ideally placed in the collimated beam path of the primary processing beam after any expansion and before focusing, i. the focusing does not take place on the primary processing beam, but on the at least two processing beams after the division.

In a further alternative development, the beam splitter device is designed as a diffractive optical element, for example as a diffraction grating or the like. In particular, the diffractive optical element can be used to divide the primary processing beam into a plurality of processing beams, which ideally have identical properties and only differ in the respective angles at which they impinge on the scanner device. From a primary laser beam, e.g. 500 W power and a focus diameter in the working plane of about 100 microns, the diffractive optical element, for example, five laser beams produce, each having a power of 100 W and a diameter of 100 microns. If the five processing beams are moved side by side and parallel within an irradiated partial area, a strip or an area with a width of approximately 500 μm is melted. In this way, in the same time five times as much material can be melted as with the primary processing beam, which has only a diameter of 100 microns.

In a further embodiment, the irradiation device comprises a movement device for at least partial movement of the beam splitter device into the beam cross section of the primary processing beam and out of the beam cross section of the primary processing beam. As described above, the Wedge plate are introduced into the beam path of the primary processing beam so that it covers only half the beam cross-section. For the rapid movement of the wedge plate into and out of the beam path, the movement device can in particular perform a rotational or a pivoting movement of the wedge plate about an axis of rotation. The movement device can be designed for this purpose, for example, as a fast so-called wedge switch, as it is used for coupling into a 2 in 1 fiber. The movement device can be designed to move a respective diffractive optical element into and out of the beam path of the primary processing beam with a linear movement and / or with a rotational movement. For the control of the movement device, the control device described above can also be used.

In a further embodiment, the irradiation device has a focus position correction device for correcting the focus positions of the processing beams, which is arranged in the beam path of the primary processing beam. As described above, due to the comparatively small difference angle of the machining beams, the focus position correction in the primary machining beam depending on the position in the machining plane can be performed. As a focus position correction device, for example, serve a so-called varioSCAN focusing device, as offered by the company. Scanlab GmbH.

In a further embodiment, the irradiation device has a preferably telecentric F-theta objective for focusing the processing beams in the processing plane. An F-theta lens is a special type of lens used in scanner applications. An F-theta lens, unlike an imaging (camera) lens, produces a desired line distortion to satisfy the F-theta condition f * θ = X, where X is the distance from the center of the machining field in the working plane. f is the focal length of the F-theta objective and θ is the angle at which the respective processing beam in the entrance pupil plane of the F-theta objective is aligned with the optical axis of the F-theta objective.

By means of the F-theta objective, the location-dependent variation of the distance of the processing beams in the working plane, which depends on the deflection angle of the scanner device, can be reduced. When using a telecentric F-theta objective or generally a telecentric lens, the processing beams (substantially) regardless of the deflection and thus regardless of the location in the edit field always perpendicular to the edit field, so that virtually no location-dependent variation of the distance between the processing beams more occurs in the editing level.

It is understood that the irradiation device described above or a processing machine comprising the irradiation device can have at least one beam source, in particular at least one laser source, for generating the at least one primary machining beam or the primary laser beam. In particular, laser sources having a power in the range of more than 100 W can be used.

Another aspect relates to a processing machine for producing three-dimensional components by irradiation of powder layers, comprising: an irradiation device, as described above, and a processing chamber with a processing plane, in which the powder layer to be irradiated can be arranged. The processing machine can for example as in the EP 3 023 228 A1 be described, which is made by reference in its entirety to the content of this application. In the processing chamber, a production space is provided in which typically a work surface is arranged at the level of the working plane. The processing area of the irradiation device is formed in a part of the work surface in which a building platform area is provided for providing a powder bed whose uppermost powder layer lies in the working plane. For the provision of the powder, a powder reservoir area with a powder reservoir can be provided in the processing chamber. A pusher disposed in the processing chamber may serve to transfer the powder from the powder reservoir into the build platform area.

In one embodiment, the processing machine has a supply device for providing a gas flow which flows over the processing plane in a construction platform area provided for providing a powder bed, and whose flow direction is preferably at least partially directed counter to the direction of movement of the processing beams and / or at which the control device is formed to determine the order of irradiation of the subregions as a function of the distance of the respective subregions in the flow direction from a provision device for providing the gas flow. The gas stream can be as in the above cited EP 3 023 228 A1 to remove smoke from the processing chamber. The gas system used to provide the gas stream, for example, as in the EP 3 023 228 A1 described is to be trained. To ensure that the movement of the processing beams is at least partially directed opposite to the direction of flow of the gas stream, the irradiation may, for example, in the WO 2014/125280 A1 described manner, even if this slows the irradiation.

Further advantages of the invention will become apparent from the description and the drawings. Likewise, the features mentioned above and the features listed further can be used individually or in combination in any combination. The embodiments shown and described are not to be understood as exhaustive enumeration, but rather have exemplary character for the description of the invention.

• 1a eine schematische Darstellung einer Bestrahlungseinrichtung mit einer Strahlteilereinrichtung zur Aufteilung eines primären Bearbeitungsstrahls in zwei Bearbeitungsstrahlen, die auf unterschiedliche Positionen in einer Bearbeitungsebene ausgerichtet werden,
• 1b ein Detail der Strahlteilereinrichtung in Form einer Keilplatte zur Umlenkung der Hälfte des Strahlquerschnitts des primären Bearbeitungsstrahls,
• 2 eine schematische Darstellung einer Bearbeitungsmaschine zum Herstellen von dreidimensionalen Bauteilen durch Bestrahlen von Pulverschichten mit der Bestrahlungseinrichtung gemäß 1a,
• 3a,b schematische Darstellungen von Teilbereichen eines zusammenhängenden Flächenbereichs in der Mitte und am Rand eines Bearbeitungsbereichs einer Scannereinrichtung,
• 4 eine schematische Darstellung einer Bearbeitungsmaschine mit einer Bestrahlungseinrichtung mit drei Strahlquellen,
• 5a,b schematische Darstellungen der Bestrahlung eines kreisförmigen Flächenbereichs einer Schicht eines dreidimensionalen Bauteils mit der Bearbeitungsmaschine von 4, sowie
• 6 eine schematische Darstellung der Bestrahlung eines zusammenhängenden Flächenbereichs mit einer Mehrzahl von rhomboiden Teilbereichen.

Show it:

• 1a 1 a schematic representation of an irradiation device with a beam splitter device for splitting a primary processing beam into two processing beams which are aligned at different positions in a processing plane,
• 1b a detail of the beam splitting device in the form of a wedge plate for deflecting half of the beam cross section of the primary processing beam,
• 2 a schematic representation of a processing machine for producing three-dimensional components by irradiating powder layers with the irradiation device according to 1a .
• 3a, b schematic representations of partial areas of a contiguous surface area in the middle and at the edge of a processing area of a scanner device,
• 4 a schematic representation of a processing machine with an irradiation device with three beam sources,
• 5a, b schematic representations of the irradiation of a circular surface area of a layer of a three-dimensional component with the processing machine of 4 , such as
• 6 a schematic representation of the irradiation of a contiguous surface area with a plurality of rhomboid portions.

1a shows an irradiation device 1 for an in 1a not shown processing machine. The irradiation device 1 is used to illuminate a contiguous surface area 2 a powder layer 3 , which is rectangular in the example shown. For the irradiation of the irradiation device 1 from one in 1 not illustrated beam source in the form of a laser source, a primary processing beam 4 supplied in the form of a laser beam. The irradiation device 1 has a scanner device 5 with two rotatable scanner mirrors 6a . 6b (Galvano mirrors), which serve to deflect the primary processing beam 4 or of two processing beams 4a . 4b serve, in which the processing beam 4 on a beam splitter device in the form of a transparent wedge plate 7 is split. The wedge plate 7 can with the help of a movement device 8th in the example shown in the circular beam cross-section A of the primary processing beam 4 in and out of the beam cross section A of the primary processing beam 4 to be moved out. At the in 1a The example shown is the wedge plate 7 only partially in the beam cross section A of the primary processing beam 4 moved into it, and that until half the A / 2 of the beam cross section A covered like this in 1b can be seen. In this way, the performance of the primary processing beam 4 in equal parts on the two processing beams 4a . 4b divided up.

The wedge plate 7 has a wedge angle γ that causes the second processing beam 4b opposite the first processing beam 4a (and opposite to the primary processing beam 4 ) at a differential angle δ is diverted. The difference angle δ depends on the wedge angle in a manner known to those skilled in the art γ and the refractive index of the material of the wedge plate 7 from. The difference angle δ becomes with the double deflection or reflection of the processing beams 4a . 4b at the two scanner mirrors 6a . 6b the scanner device 5 maintained so that the two processing beams 4a . 4b in different positions P1 . P2 in the contiguous area 2 on the powder layer 3 to meet. In the example shown, the difference angle runs δ in the XZ plane of an XYZ coordinate system, ie the two positions P1 . P2 the two processing beams 4a . 4b are at a distance in a first direction, hereinafter referred to as X-direction 2 L spaced apart. The distance 2 L of positions P1 . P2 the two processing beams 4a . 4b on the powder layer 3 depends on the difference angle δ also from the (known) distance of the working plane e from the irradiation device 1 or from the scanner device 5 from. The processing plane E lies in the example shown in the XY plane of the XYZ coordinate system.

The movement device 8th is in the example shown for rotation of the wedge plate 7 one parallel to the beam direction of the primary machining beam 4 extending axis of rotation formed. It turned out that with the help of a rotary motion the wedge plate 7 particularly fast in the beam cross section A of the primary processing beam 4 in and out of this can be moved. This is advantageous in order to switch as quickly as possible between irradiation of the powder layer 3 with the primary processing beam 4 and irradiation of the powder layer 3 with the two processing beams 4a . 4b to enable.

As in 1a can also be seen, is in the beam path of the two processing beams 4a . 4b after the beam splitter device 7 a (static) focusing device 9 arranged in the form of a focusing lens to the processing beams 4a . 4b in the working plane e to focus. In the beam path of the primary processing beam 4 is a focus position correction device 10 arranged for (dynamic) correction of focus positions F1 . F2 the two processing beams 4a . 4b (in beam direction) is used to ensure that the focus positions F1 . F2 as in 1a is shown in the working plane e lie. The focus position correction device 10 is required because of the focusing lens 9 focused and from the scanner setup 5 deflected processing beams 4a . 4b in a bowl and not as desired in the working plane e would be focused. The focus position correction device 10 is in the primary processing beam 4 arranged as the positions P1 . P2 the processing beams 4a . 4b in the working plane e a comparatively small distance 2 L typically less than about 1.0 mm, so that individual focus position correction of the two processing beams 4a . 4b can be waived. As focal position correction device 10 For example, a so-called varioSCAN focusing device can be used, as marketed by Scanlab GmbH.

The in 1a shown contiguous surface area 2 is from a border contour 11 surrounded, which corresponds to the outer contour of a layer of the three-dimensional component, during the irradiation of the powder layer 3 should be generated. For the production of the three-dimensional component, the entire surface within the edge contour 11 be irradiated. The area within the edge contour 11 is in the example shown in the contiguous surface area 2 split, which with the help of the two processing beams 4a . 4b is irradiated, as well as in a border area 12 that is between the contiguous area 2 and the edge contour 11 is formed. The contiguous surface area 2 is by means of the two processing beams 4a . 4b irradiated simultaneously, as described in more detail below. The border area 12 as well as the edge contour 11 on the other hand, with the primary processing beam 4 irradiated, including the beam splitter device 7 with the help of the movement device 8th from the beam path of the primary processing beam 4 Will get removed.

The example shown in the rectangular rectangular continuous area 2 is divided into a plurality of square portions for the irradiation, in a total of eight partial areas in the longitudinal direction (X direction) and in three partial areas in the transverse direction (Y direction) of the continuous surface area 2 of which six are subareas T1 to T6 in 1a are shown. The subareas T1 . T2 , ... have a length L in the X direction, which may be, for example, 1.0 mm, and an identical length in the Y direction. Unlike in 1a is shown, the subregions T1 . T2 , ... have another, eg rectangular geometry. It is also possible that the subareas T1 . T2 , ... have another, for example rhomboid, diamond-shaped or basically any geometry, provided that they are arranged in a regemäßigen arrangement in the manner of a grid or a matrix.

As in 1a can also be seen, the two in the X direction in the working plane e mutually offset processing beams 4a . 4b used to simultaneously create two quadratic subareas T3 . T4 of the contiguous surface area 2 between which a gap is formed, which is exactly the size of a subarea T1 to T6 having. As described above, the positions are pointing P1 . P2 the two processing beams 4a . 4b in the working plane e a distance 2 L each other, ie a distance of twice the length L a respective subarea T1 to T6 equivalent. The simultaneous irradiation of two partial areas T3 . T4 which are not disposed immediately adjacent, has regard to the heat balance of the melt of the powder layer 3 proved to be advantageous. Unlike in 1a is shown, the distance between the two processing beams 4a . 4b in the X direction another integer multiple, for example, four times the length L a respective subarea T1 to T6 correspond. The number of subregions in which the contiguous surface area 2 in the X direction should be divided by the integer multiple of the length L a respective subarea T1 to T6 be divisible. This is usually possible as the length L of the subareas T1 to T6 can be freely chosen within certain limits.

For the irradiation of the two partial areas T3 . T4 become the positions P1 . P2 the two processing beams 4a . 4b in the working plane e simultaneously using the scanner device 5 changed until the powder layer 3 in the two subareas T3 . T4 completely melted. In the example shown, the simultaneous change of positions P1 . P2 the two processing beams 4a . 4b the two processing beams 4a . 4b in a scanning motion over the entire edge length L of the subregions T3 . T4 moved in the Y direction. At the edge of the respective subarea T3 . T4 there is a reversal of motion, in which the two processing beams 4a . 4b slightly offset in the X direction to drive an adjacent track in the Y direction in a scanning movement. Subsequently, a further reversal of motion of the two processing beams in the X direction. This process is repeated until the two subregions T3 . T4 completely, ie over the entire surface, are melted.

After irradiation of the third and fourth part T3 . T4 be by means of the two processing beams 4a . 4b two further subareas, namely the fifth and sixth subarea T5 . T6 irradiated. For this purpose, the two processing beams 4a . 4b first in the fifth and sixth part T5 . T6 moves, ie their positions P1 . P2 in the working plane e are changed appropriately. When repositioning the two processing beams 4a . 4b These are typically turned off by an in 1a not shown beam source is briefly deactivated. If necessary, the positions P1 . P2 the two processing beams 4a . 4b at the end of the irradiation of the third and fourth subareas T3 . T4 be chosen so that these in a corner of the third and the fourth sub-area T3 . T4 which are also a corner of the fifth and the sixth sub-area T5 . T6 forms. In this case, the irradiation of the fifth and sixth part T5 . T6 directly to the irradiation of the third and fourth subarea T3 . T4 connect. The irradiation of the fifth and sixth subarea T5 . T6 takes place as described above, ie by simultaneously changing the positions P1 . P2 the two processing beams 4a . 4b in the fifth and sixth subarea T5 . T6 until they are completely melted. The remaining subregions of the contiguous surface area also become corresponding 2 irradiated, for example, the first and the second in 1a shown subarea T1 . T2 until the entire contiguous area 2 is irradiated.

Optionally, those subregions, which in the contiguous surface area 2 the gaps between the first and the second part T1 . T2 , the third and the fourth subarea T4 . T5 , the fifth and the sixth subarea T5 . T6 etc., with the help of the two processing beams 4a . 4b can be machined by simultaneously moving them in the Y direction and not in the X direction. For this purpose, the irradiation device 1 have a further beam splitter device, for example in the form of another, rotated by 90 ° wedge plate to the primary processing beam 4 in two processing beams 4a . 4b to divide their positions P1 . P2 in the working plane e offset in the Y direction.

In a subsequent or previous step, the border area 12 as well as the edge contour 11 with the primary processing beam 4 be irradiated to the inside of the edge contour 11 completely irradiate the surface. The coordination of movements of the scanner mirror 6a . 6b and the beam splitter device 7 takes place in the example shown by means of a in 2 shown control device 14 the irradiation device 1 ,

The orientation of the X-direction and the Y-direction in the working plane e is basically arbitrary. In the example shown, the positive Y-direction coincides with the flow direction of a protective gas flow 13 match that over the powder layer 3 to be led. The protective gas flow 13 is in a processing chamber 16 one in 2 shown processing machine 15 over the powder layer 3 led, which is the topmost layer of a powder bed 19 forms, in which a three-dimensional component 20 More precisely, the already produced layers of the three-dimensional component 20 are embedded. The powder bed 19 is in a building platform area 17 formed, which has a cylindrical, for example, construction platform with a stamp, at the top of the working plane e is formed by the irradiation device 1 is irradiated in the manner described above. The processing machine 15 also has a beam source 23 in the form of a laser source for generating the primary processing beam 4 on.

The processing machine 15 also has a provisioning facility 21 for the provision of the protective gas flow 13 on that in 1a is indicated. Alternatively to providing a protective gas stream 13 , which has a flow direction in the positive Y direction, the protective gas flow 13 have a flow direction in positive or negative X-direction or otherwise oriented. The protective gas flow 13 gets over the build platform area 17 led to smoke from the overlying irradiation device 1 To keep away, for example, from a window formed there. The provisioning device 21 can, for example, as in the above-cited EP 3 023 228 A1 be educated. To ensure that the flow direction of the protective gas flow 13 (here: positive Y direction) at least partially the direction of movement of the processing beams 4a . 4b in the working plane e is directed opposite, can in a synchronous movement of the processing beams 4a . 4b in the Y direction, as in 1a is shown, the exposure of the subregions T1 to T6 done by the processing beams 4a . 4b synchronous only in the negative Y direction via the respectively jointly illuminated partial areas T1 . T2 ; T3 . T4 ; T5 . T6 be moved, ie it eliminates the opposite movement in the positive Y-direction, as in the above cited WO 2014/125280 A1 is shown. It is also possible to change the order of irradiation of the subregions T1 . T2 , ... depending on the distance of the respective subarea T1 . T2 , ... in the direction of flow + Y from the supply device 21 to choose. In particular, subareas may be used here T1 . T2 , ..., which are a greater distance from the provisioning device 21 in the direction of flow + Y, before partial areas T1 . T2 , ... are irradiated, the closer distance to the supply device 21 in the direction of flow + Y have.

For creating a new layer of the three-dimensional component 20 is first made from one in the processing chamber 16 arranged powder reservoir container 22 Powder taken from a powder reservoir area 18 in which the powder reservoir container 22 is located in the building platform area 17 spent. In the example shown, a pusher not shown in detail is used for this purpose, which powder from the powder reservoir area 18 in the building platform area 17 transferred by placing the powder on top of one in the working plane e moved workspace is moved. The stamp in the building platform area 17 and thus the powder bed 19 is shifted parallel to the layer thickness of a powder layer down, as in 2 indicated by an arrow before the irradiation of the (new) powder layer 3 in the building platform area 17 is carried out.

A processing area B for carrying out the irradiation of the powder layer 3 is laterally through the building cylinder of the building platform area 17 limited. The dimension of the processing region B, which may for example be about 30 cm, is at the (maximum) deflection angle α of the primary processing beam 4 through the scanner device 5 adjusted, ie the scanner mirror 6a . 6b can be rotated so far about their respective axis of rotation that any location of the machining area B in the working plane e can be achieved.

As in 3a, b is shown, the distance between the two positions depends P1 . P2 in the working plane e from in 2 illustrated deflection angle α of the scanner device 5 for the two processing beams 4a . 4b from, that is, at which point of the editing area B the two processing beams 4a . 4b on the working level e to meet. Like both in 3a as well as in 3b can be seen, the distance between the two processing beams decreases 4a . 4b from the center M of the machining area B to the side edge of the editing area B continuously too. The distance between two subareas is corresponding T1 . T2 that of the two processing beams 4a . 4b be generated, depending on the X-coordinate along the machining area B ,

The difference angle δ between the two processing beams 4a . 4b in the X direction can by selecting the wedge angle γ the wedge plate 7 be set. 3a shows the two processing beams 4a . 4b at a first differential angle δ ₁ , in which the two partial areas T1 . T2 on the edge R of the editing area B immediately adjacent to each other while in the middle M of the machining area B overlap slightly in the X direction, and usually by a proportion of the length L of the respective sub-area T1 . T2 which does not exceed 10%. 3b shows the two processing beams 4a . 4b at a second, slightly larger differential angle δ ₂ in which the two subareas T1 . T2 in the middle M of the editing area B immediately adjacent to each other while the two subregions T1 . T2 at the edge of the editing area B are slightly spaced apart, for example, about 1 mm.

At the in 3a shown first difference angle δ ₁ is the irradiation in the middle M of the editing area B less effective because the subareas T1 . T2 overlap and in the overlap area a double irradiation of the powder layer 3 he follows. At the in 3b shown difference angle δ ₂ overlap the two sections T1 . T2 in the middle M of the editing area B not, but it is usually an additional irradiation with the primary processing beam 4 required to fill the gap between the two subareas T1 . T2 on the edge R of the editing area B also to be irradiated. The problem described above can be avoided if the processing beams 4a . 4b be used to simultaneously one and the same subarea T1 respectively. T2 to irradiate, as described below.

4 shows a processing machine 15 that differ from the in 2 shown processing machine 15 essentially by the design of the irradiation device 1 differs, as well as in that the processing machine 15 in place of a single beam source 23 three beam sources 23 . 23a . 23b having. The first beam source 23 generates a first primary machining beam 4 in the example shown on a beam splitter device in the form of a diffractive optical element 24 (Diffraction grating) in five processing beams 4a-e is split, which has a scanner device 5 on the working level e aligned or in Direction to the processing level e be redirected. The second beam source 23a generates another (second) primary machining beam 25 at another (second) beam splitter device 24a , which is also designed as a diffractive optical element, in five other processing beams 25a-e is split, which has another scanner device 25b on the working level e be aligned. The third beam source 23b creates another (third) primary machining beam 26 , which has a third scanner device 5b on the working level e is aligned. On the representation of further optical elements of the irradiation device 1 which, for example, like the one in 1a shown irradiation device 1 could be trained in 4 omitted for the sake of clarity.

As with the in 2 example shown can also be found in the 4 shown irradiation device 1 the two beam splitter devices in the form of diffractive optical elements 24 . 24a into the beam path of the primary machining beam 4 or the further primary processing beam 4a in and out of this are moved, including corresponding movement facilities 8th . 8a are provided, which in the example shown a linear movement of the diffractive optical elements 24 . 24a enable. As in 4 is also indicated, the two beam splitter devices 24 . 24a arranged such that the division of the respective primary processing beams 4 . 25 on the five processing beams 4a-e . 25a-e in two mutually perpendicular directions (X-direction or Y-direction) takes place, so that the positions P1 to P5 the processing beams 4a-e in the working plane e in the X direction are spaced apart, while the positions P1 to P5 the further processing beams 25a-e in the working plane e are spaced apart in the Y direction.

At the in 4 shown irradiation device 1 serves a telecentric F-theta lens 27 for focusing the processing beams 4a-e , the further processing beams 25a-e and the (third) primary machining beam 26 in the working plane e , The processing beams 4a-e , the other processing beams 25a-e and the primary processing beam 26 Because of the telecentricity, regardless of the location on the edit field, they always hit the working plane vertically e so that at the in 4 shown irradiation device 1 practically no location-dependent variation of the distances between the positions P1 to P5 , ... occurs. It is understood that a (telecentric) F-theta lens 27 also at the in 1a shown irradiation device can be used.

For the complete irradiation of one of a circular edge contour 11 bordered surface of a cylindrical in the example shown three-dimensional component 20 For example, an irradiation may be performed in which only the three primary processing beams 4 . 25 . 26 be used as in 5a is shown. In this example, the of the circular edge contour 11 limited area in square sections T or at the edge of the circular area by the circular edge contour 11 divided partial areas T split. Each of the subregions T becomes one of the three primary processing beams 4 . 25 . 26 irradiated until the corresponding portion T is completely melted. In 5a are the three processing beams 4 . 25 . 26 , more precisely, their movement in the subareas T indicated by different dashed arrows. The subareas T are traversed in a scanning motion, as described above in connection with 1a is described. The assignment of the three primary processing beams 4 . 25 . 26 to the subareas T is basically arbitrary. Also, one and the same processing beam 4 . 25 . 26 some of the sections T depart with a scanning motion in the Y direction, while others of the sections T be scanned with a scanning movement in the X direction, etc.

At the in 5b shown irradiation within the circular edge contour 11 formed area is - unlike that in 5a is shown - initially a contiguous surface area 2 defined by means of the split processing beams 4a-e . 25a-e is irradiated, as described in more detail below. The outside of the contiguous surface area 2 located edge area 12 as well as the edge contour 11 is, however, by means of the third primary processing beam 26 irradiated. The border area 12 is in the example shown in third sections T3 split, one after the other from the third primary processing beam 26 be irradiated.

As in 5b can be seen, the coherent surface area 2 twelve square sections T1 . T2 as well as four subareas T1 . T2 on, in one direction (X-direction or Y-direction) only half the edge length of the square sections T1 . T2 exhibit. For the irradiation is a respective first subarea T1 in each case the first (primary) processing beam 4 or the five (first) processing beams 4a-e assigned during a respective second subarea T2 the second primary processing beam 25 or the five (second) processing beams 25a-e assigned. As related to 4 has been described, becomes the first primary processing beam 4 on five processing beams 4a-e split their positions P1 to P5 in the X direction from each other are spaced. Unlike the in 1a described example, the five processing beams 4a-e at the in 5b not shown simultaneously on different sub-areas T3 . T4 but on the same first subarea T1 irradiated, each offset in the X direction, as in 5b can be seen by the arrows. The five processing beams 4a-e will be similar to the one in 5a shown in the X direction parallel offset in a scanning movement in the Y direction over the entire edge length of a respective first portion T1 emotional. As related to above 5a has been shown, takes place at the edge of a respective first subsection T1 a reversal of motion with a lateral offset in the X direction, before the five processing beams 4a-e be moved in opposite directions in the Y direction. The irradiation of the second parts T2 by means of the second processing beams 25a-e takes place analogously to the irradiation of the first subregions T1 , with the difference that the X direction and the Y direction are reversed. As in 5b can also be seen, it may be sufficient if the small first sections T1 only in a single scanning movement with the five processing beams 4a-e are irradiated to completely melt them, ie in this case no reversal of motion is required. The same applies to the irradiation of the small second partial areas T2 with the second five processing beams 25a-e ,

By splitting the two primary processing beams 4 . 25 on the five processing beams 4a-e . 25a-e with the help of diffractive optical elements 24 . 24a show the five processing beams 4a-e . 25a-e in the working plane e each about the same diameter as the two primary processing beams 4 . 25 , In this way, the width of the machining beams 4a-e . 25a-e during a crossing swept area in the working plane e be increased by five times, ie, for example, from a width of 100 microns to a width of 500 microns. In this way, the fivefold surface can be melted in the same time as with a respective primary processing beam 4 . 25 , It is understood that instead of five processing beams 4a-e . 25a-e Also, a larger or smaller number of processing beams can be used to a respective first portion T1 or a respective second subarea T2 to irradiate.

For the implementation of related 5b described method is not necessarily an irradiation device 1 or a processing machine 15 required as in 4 is shown. Rather, if appropriate, a single primary processing beam can also be used 4 be used for this purpose, in the beam path optionally the first diffractive optical element 24 or the second diffractive optical element 24a can be introduced to the first subareas T1 or the second partitions T2 to irradiate. In this case, the irradiation of the subregions thus takes place T1 . T2 sequentially, while at the in 4 shown processing machine 15 the irradiation of the first sections T1 and the second subareas T2 time can be performed in parallel.

6 shows an example of a contiguous area 2 , which is not square, but rhomboid, ie parallelogram-shaped portions T1 . T2 having. The length L of the subareas T1 . T2 deviates in the example shown by the width B but it is also possible that the length L and the width B of the subareas T1 . T2 matches, so that they are diamond-shaped. In the example shown, a respective first partial area T1 related to the above 5b described manner with two offset in the X direction first processing beams 4a . 4b irradiated. Accordingly, a respective second subarea T2 with the help of two in the Y direction offset from each other second processing beams 25a . 25b irradiated, in the X'-direction, the direction of the long outer edge of the rhomboid portions T1 . T2 equivalent. At the in 6 the example shown, the movement of the second processing beams 25a . 25b over the second parts T2 thus in a direction (X'-direction) which is not perpendicular to the direction (Y-direction), along which the first processing beams 4a . 4b over the first subareas T1 to be moved. It is preferred in the subregions T1 . T2 the distance between the first processing beams 4a . 4b if possible kept the same size as the distance between the second processing beams 25a . 25b , If an equal distance due to unequal side lengths of the sections T1 . T2 is not possible, the distances between the first processing beams 4a . 4b and second processing beams 25a . 25b kept as similar as possible.

It is understood that the irradiation of the respective subregions T1 . T2 , ... does not necessarily have to be done in a scanning motion, but that when irradiating a particular sub-area T1 . T2 , ... used pattern is basically arbitrary, even if the use of a scanning motion is usually favorable.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2015/191257 A1 [0004, 0009]
• WO 2016/128430 A1 [0005]
• EP 2875897 B1 [0006]
• WO 2014/125280 A1 [0017, 0045, 0060]
• EP 3023228 A1 [0044, 0045, 0060]

Claims (20)

Method for producing a coherent surface area (2) of a three-dimensional component (20) by irradiating a powder layer (3) with at least two processing beams (4a, b; 4a-e), in particular with at least two laser beams, comprising: Splitting a primary machining beam (4) onto the at least two machining beams (4a, b; 4a-e), Guiding the at least two processing beams (4a, b; 4a-e) to a common scanner device (5) for aligning the at least two processing beams (4a, b; 4a-e) to different positions (P1, P2; P1 to P5) in one Processing plane (E) of the scanner device (5) in which the contiguous surface area (2) is, wherein the generation of the continuous surface area (2), for the irradiation in a plurality of preferably rhomboid, in particular diamond-shaped, rectangular or square sections ( T1 to T6, T1, T2) comprises: Simultaneously changing the positions (P1, P2, P1 to P5) of the at least two processing beams (4a, b; 4a-e) in a partial area (T1) or in at least two different partial areas (T3, T4) of the continuous area (2), until the powder layer (3) is completely melted in the partial area (T1) or in the at least two partial areas (T3, T4), as well as simultaneously changing the positions (P1, P2; P1 to P5) of the at least two processing beams (4a, b) or of at least two further processing beams (25a-e) in a further subregion (T2) or in at least two different further subregions (T5, T6) of the continuous surface region (2) until the powder layer (3) in the further subregion (T2) or in the at least two further subregions (T5, T6) is completely melted. Method according to Claim 1 in which the contiguous surface area (2) is surrounded by an edge contour (11) of the three-dimensional component (20), wherein the edge contour (11) and / or an edge area formed between the edge contour (11) and the contiguous surface area (2) ( 12) is irradiated with the primary processing beam (4), in particular with the primary laser beam, or with a further processing beam (26), in particular with a further laser beam. Method according to Claim 1 or 2 in which the different positions (P1, P2, P1 to P5) of the machining beams (4a, b; 4a-e) in the partial area (T1) or in the at least two partial areas (T3, T4) in a first direction (X) in the working plane (E) and the simultaneous changing of the positions (P1, P2, P1 to P5) of the at least two processing beams (4a, b; 4a-e) in the subregion (T1) or in the at least two subregions ( T3, T4) comprises a simultaneous movement of the processing beams (4a, b; 4a-e) in a second, preferably to the first vertical direction (Y) in the processing plane (E). Method according to Claim 3 in which a gas flow (13) is guided over the powder layer (3) whose flow direction (+ Y) is at least partially directed counter to the direction of movement (-Y) of the processing jets (4a, b; 4a-e) and / or in which the sequence of irradiation of the partial regions (T1, T2,...) preferably depends on the distance of the respective partial regions (T1, T2,...) in the flow direction (+ Y) from a supply device (21) for providing the gas flow (13 ) he follows. Method according to one of Claims 3 or 4 in which the positions (P1, P2) of the at least two processing beams (4a, 4b) in the first direction (X) have a distance (2 L) from each other substantially equal to an integer multiple of the extent (L) of a respective portion ( T3, T4) in the first direction (X). Method according to one of Claims 3 to 5 in which a difference angle (δ ₁ , δ ₂ ) between the at least two machining beams (4a, 4b) in the first direction (X) when aligning the at least two machining beams (4a, 4b) to different positions (P1, P2) in the Machining plane (E), the distance (A) in the working plane (E) depending on a deflection angle (α) of the scanner device (5) varies location-dependent, is selected so that either adjacent portions (T1, T2) in the middle of the processing area ( B) adjoin one another in the first direction (X) or adjacent subareas (T1, T2) adjoin one another at the edge of the processing region (B) in the first direction (X). Method according to one of Claims 1 to 4 in which the positions (P1 to P5) of the processing beams or of the further processing beams (25a-e) in the further subarea (T2) or in the at least two further subareas are offset from one another in a second direction (Y) and the simultaneous changing of the Positions (P1 to P5) of the at least two processing beams or the at least two further processing beams (25a-e) in the further sub-area (T2) or in the at least two further sub-areas a simultaneous movement of the processing beams or the further processing beams (25a-e) a first, preferably to the second vertical direction (X). Method according to Claim 7 , further comprising: splitting a further primary processing beam (25) on the at least two further processing beams (25a-e), and guiding the at least two further processing beams (25a-e) to a further common scanner device (5a) for aligning the at least two others Processing beams (25a-e) to different positions (P1 to P5) in the processing plane (E). Method according to one of the preceding claims, wherein a focus position correction for correcting the focus positions (F1, F2) of the processing beams (4a, 4b) in the beam path of the primary processing beam (4) is performed. Irradiation device (1) for a processing machine (15) for producing three-dimensional components (20) by irradiation of powder layers (3), comprising: a beam splitting device (7, 24) for splitting a primary processing beam (4, 25), in particular a laser beam, on at least two processing beams (4a, b; 4a-e), in particular on at least two laser beams, and a scanner device (5) for aligning the at least two processing beams (4a, b; 4a-e) to different positions (P1, P2; P1 to P5) in a working plane (E), characterized by a control device (14), which is formed, the positions (P1, P2, P1 to P5) of the at least two processing beams (4a, b; 4a-e) in a partial area ( T1) or in at least two subregions (T3, T4) of a continuous surface area (2), which for the irradiation in a plurality of preferably rhomboid, in particular diamond-shaped, rectangular or square subareas (T1 to T6; T1, T2) is divided, simultaneously to change, until the powder layer (3) in the partial area (T1) or in the at least two partial areas (T3, T4) is completely melted, and which is formed, the positions (P1, P2; P1 to P5) of the at least two processing beams (4a, 4b) or of at least two further processing beams (25a-e) in a further subregion (T2) or in at least two different further subregions (T5, T6) of the contiguous surface region (2) simultaneously until the powder layer (3) is completely melted in the further partial region (T2) or in the at least two further partial regions (T5, T6). Irradiation device after Claim 10 , further comprising: a further beam splitting device (24a) for splitting a further primary processing beam (25), in particular a further laser beam, on the at least two further processing beams (25a-e), in particular on the at least two further laser beams, and a further scanner device ( 5a) for aligning the at least two further processing beams (25a-e) to different positions (P1 to P5) in the processing plane (E). Irradiation device after Claim 10 or 11 in which the beam splitting device (7, 24) for splitting the primary machining beam (4, 25) onto the at least two machining beams (4a, 4b; 4a-e) is formed by splitting a beam cross section (A) of the primary machining beam (4, 25) is. Irradiation device after Claim 12 in which the beam splitter device (7) is designed to divide the primary processing beam (4) by deflecting at least a portion (A / 2) of the beam cross section (A) of the primary processing beam (4). Irradiation device after Claim 13 in which the beam splitter device is constructed as a wedge plate (7) transparent to the primary processing beam (4). Irradiation device according to one of Claims 10 to 12 in which the beam splitter device is designed as a diffractive optical element (24). Irradiation device according to one of Claims 10 to 15 , further comprising: a movement device (8) for at least partially moving the beam splitter device (7, 24) into the beam cross-section (A) of the primary processing beam (4) and out of the beam cross-section (A) of the primary processing beam (4). Irradiation device according to one of Claims 10 to 16 further comprising: focal position correcting means (10) for correcting the focus positions (F1, F2) of the machining beams (4a, 4b) disposed in the beam path of the primary machining beam (4). Irradiation device according to one of Claims 10 to 17 , further comprising: a preferred telecentric F-theta objective (27) for focusing the processing beams (4a, 4b) in the processing plane (E). Processing machine (15) for producing three-dimensional components (20) by irradiation of powder layers (3), comprising: an irradiation device (1) according to one of the preceding claims, as well as a processing chamber (16) with a working plane (E), in which the powder layer (3) to be irradiated can be arranged. Processing machine after Claim 19 , further comprising: a supply device (21) for providing a gas flow (13) which flows over the processing plane (E) in a building platform region (17) provided for the provision of a powder bed (19) and whose flow direction (+ Y) is preferably at least partially facing the direction of movement (-Y) of the processing beams (4a, b; 4a-e) and / or in which the control device (14) is formed, the order of irradiation of the subregions (T1, T2, Dependence on the distance of the respective subregions (T1, T2,...) In the flow direction (+ Y) from a provision device (21) for providing the gas flow (13).

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