Three-dimensional modeling apparatus and three-dimensional modeling method

Abstract

A three-dimensional modeling apparatus models a three-dimensional object by irradiating an electron beam to a powder material to melt the powder material and perform layering. The three-dimensional modeling apparatus has an energy beam emission unit that emits an electron beam to irradiate the electron beam to the powder material. The energy beam emission unit scans and irradiates the electron beam to the powder material in a direction orthogonal to a contour line of a modeling region in at least a profile portion of the modeling region as a cross section of the object.

Description

Technical Field

[0001] This disclosure describes a three-dimensional modeling apparatus and a three-dimensional modeling method for modeling three-dimensional objects. Background Technology

[0002] Conventional methods for creating three-dimensional models include, for example, the apparatus and method for modeling three-dimensional objects described in U.S. Patent No. 5,155,324. This apparatus and method irradiate a powder material with a laser beam, thereby sintering the powder material and simultaneously depositing the sintered powder material. The irradiation pattern of the energy beam used in this apparatus and method includes a pattern along the contour of a cross-section (outline) and a pattern filling the inside of the contour (section line). In this apparatus and method, firstly, a laser beam is irradiated along the contour line of the object's cross-section. Next, the laser beam is irradiated while reciprocating in a certain direction on the portion inside the contour line, thereby modeling the object.

[0003] Patent Document 1: US Patent No. 5,155,324

[0004] Such 3D modeling devices and methods are inefficient for shaping objects. If the illumination of the energy beam onto the cross-section of an object is divided into patterns along the contour of the cross-section and patterns filling the inner part of the contour, then the intensity and scanning speed of the energy beam need to be varied in each pattern. For example, the energy beam illumination along the contour uses a low speed to scan with a weak energy beam. The energy beam illumination towards the inner part uses a high speed to scan with a strong energy beam. In this case, the energy beam illumination along the contour requires a long time, thus making it inefficient for shaping objects. Summary of the Invention

[0005] Therefore, this disclosure describes a three-dimensional modeling apparatus and a three-dimensional modeling method that can efficiently model objects.

[0006] One aspect of this disclosure is a three-dimensional modeling apparatus that shapes a three-dimensional object by melting and layering a modeling material through irradiation with an energy beam. The apparatus includes an energy beam emitting unit that emits an energy beam and irradiates the modeling material. The energy beam emitting unit is configured to scan the energy beam along a direction orthogonal to the contour line of the modeling region, at least at the contour portion of the modeling region (which is a cross-section of the object), and irradiate the modeling material. This three-dimensional modeling apparatus irradiates the modeling material with an energy beam while scanning the contour portion of the modeling region along a direction orthogonal to the contour line of the modeling region. As a result, energy beam irradiation of the contour portion at high speed is possible. Therefore, irradiation of the contour portion by the energy beam can be completed in a short time. Thus, the three-dimensional modeling apparatus can efficiently shape objects.

[0007] In one aspect of the three-dimensional modeling apparatus disclosed herein, the energy beam emitting unit can also scan and irradiate the modeling material along a certain direction from an inner portion formed within the modeling area, which is closer to the outline portion. In this case, the energy beam is scanned along a certain direction while irradiating the modeling material at the inner portion of the modeling area. As a result, energy beam irradiation at the inner portion can be completed in a short time. Therefore, object modeling can be performed in a short time.

[0008] The energy beam emitting unit of one aspect of the three-dimensional modeling apparatus disclosed herein can also irradiate multiple irradiation paths set on the contour portion with energy beams. The energy beam emitting unit can also irradiate other irradiation paths, bypassing adjacent irradiation paths, after irradiating the irradiation path with an energy beam. In this case, after irradiating the irradiation path with an energy beam, it irradiates other irradiation paths, bypassing adjacent irradiation paths. As a result, heat concentration caused by energy beam irradiation can be suppressed. Therefore, inappropriate modeling of the object can be suppressed.

[0009] The energy beam emitting unit of one aspect of the three-dimensional modeling apparatus disclosed herein can also irradiate multiple irradiation paths set on the contour portion with energy beams. The energy beam emitting unit can also, after irradiating an irradiation path with an energy beam, set an idle time and then irradiate other irradiation paths, or irradiate adjacent irradiation paths with energy beams. In this case, an idle time is set for the irradiation of the energy beam. As a result, heat concentration caused by the irradiation of the energy beam can be suppressed. Therefore, inappropriate modeling of the object can be suppressed.

[0010] The energy beam emitting unit of one aspect of the three-dimensional modeling apparatus disclosed herein can also irradiate multiple irradiation paths set on the contour portion with energy beams. The energy beam emitting unit can also irradiate multiple irradiation paths respectively in the same direction. In this case, the energy beams are irradiated in the same direction for each irradiation path. As a result, heat concentration caused by energy beam irradiation can be suppressed. Therefore, inappropriate modeling of the object can be suppressed.

[0011] One aspect of this disclosure is a three-dimensional modeling method that shapes a three-dimensional object by irradiating a modeling material with an energy beam, causing the material to melt and layer. The method comprises an irradiation step of emitting an energy beam and irradiating the modeling material. In this irradiation step, the energy beam is scanned along a direction orthogonal to the contour line of the modeling region, at least at the outline portion of the modeling region (which is a cross-section of the object), to irradiate the modeling material. According to this method, the energy beam is irradiated onto the modeling material while scanning along a direction orthogonal to the contour line of the modeling region at the outline portion. As a result, energy beam irradiation that scans the outline portion at high speed is possible. Therefore, irradiation of the outline portion with the energy beam can be completed in a short time. Thus, object modeling is achieved efficiently.

[0012] The three-dimensional modeling apparatus and method disclosed herein can efficiently model objects. Attached Figure Description

[0013] Figure 1 This is a simplified structural diagram of a three-dimensional modeling device as an embodiment of the present disclosure.

[0014] Figure 2 yes Figure 1 An explanatory diagram of the energy beam irradiation in a three-dimensional modeling device.

[0015] Figure 3 yes Figure 1 An explanatory diagram of the energy beam irradiation in a three-dimensional modeling device.

[0016] Figure 4 yes Figure 1 An explanatory diagram of the energy beam irradiation in a three-dimensional modeling device.

[0017] Figure 5 This is a flowchart illustrating the operation of the three-dimensional modeling apparatus and the three-dimensional modeling method as embodiments of this disclosure.

[0018] Figure 6 Is as Figure 1 An explanatory diagram of the energy beam irradiation of a deformed example of a three-dimensional modeling device.

[0019] Figure 7 Is as Figure 1 An explanatory diagram of the energy beam irradiation of a deformed example of a three-dimensional modeling device. Detailed Implementation

[0020] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, in the description of the drawings, the same reference numerals are used to denote the same elements, and repeated descriptions are omitted.

[0021] Figure 1 This is a simplified structural diagram of a three-dimensional modeling apparatus according to an embodiment of the present disclosure. The three-dimensional modeling apparatus 1 melts powder material A by irradiating it with an electron beam B. Then, the three-dimensional modeling apparatus 1 laminates the molten and solidified powder material A. As a result, a three-dimensional object O is modeled. The three-dimensional modeling apparatus 1 uses powder bed fusion (PBF). The three-dimensional modeling apparatus 1 uses an electron beam B as the energy beam. The three-dimensional modeling apparatus 1 models the object O using electron beam melting (EBM). Powder material A is the modeling material used to model the object. Powder material A is composed of multiple powder particles. For example, metal powder is used as powder material A. As long as powder material A can be melted and solidified by irradiation with electron beam B, particles with a particle size larger than the powder can be used. Electron beam B is the energy beam used to dissolve powder material A.

[0022] The three-dimensional modeling device 1 includes an energy beam emitting unit 2, a modeling unit 3, and a control unit 4. The energy beam emitting unit 2 emits an electron beam B onto the powder material A in the modeling unit 3. That is, the energy beam emitting unit 2 melts the powder material A. The electron beam B is formed by the linear motion of electrons. For example, the energy beam emitting unit 2 preheats the powder material A by irradiating it with the electron beam B. Next, the energy beam emitting unit 2 melts the powder material A by irradiating it with the electron beam B. As a result, a three-dimensional object O is modeled.

[0023] The energy beam emitting unit 2 includes, for example, an electron gun 21, an aberration coil 22, a focusing coil 23, and a deflection coil 24. The electron gun 21 is electrically connected to the control unit 4. The electron gun 21 operates by receiving control signals from the control unit 4. The electron gun 21 emits an electron beam B. The electron gun 21 is configured, for example, to emit the electron beam B downwards. The aberration coil 22 is electrically connected to the control unit 4. The aberration coil 22 operates by receiving control signals from the control unit 4. The aberration coil 22 is positioned around the electron beam B emitted from the electron gun 21. The aberration coil 22 corrects aberrations in the electron beam B. The focusing coil 23 is electrically connected to the control unit 4. The focusing coil 23 operates by receiving control signals from the control unit 4. The focusing coil 23 is positioned around the electron beam B emitted from the electron gun 21. The focusing coil 23 converges the electron beam B. The focusing coil 23 adjusts the focusing state of the electron beam B at the irradiation position. The deflection coil 24 is electrically connected to the control unit 4. The deflection coil 24 operates by receiving control signals from the control unit 4. The deflection coil 24 is positioned around the electron beam B emitted from the electron gun unit 21. The deflection coil 24 adjusts the irradiation position of the electron beam B according to the control signals. The deflection coil 24 performs electromagnetic beam deflection, therefore the scanning speed of the electron beam B during irradiation is higher than that of mechanical beam deflection. The electron gun unit 21, aberration coil 22, focusing coil 23, and deflection coil 24 are, for example, housed within a cylindrical support column 26. Sometimes, the aberration coil 22 is omitted. Furthermore, the energy beam emission unit 2 can differ from the above structure as long as it can emit the electron beam B.

[0024] The shaping section 3 is the part used to shape the desired object O. The shaping section 3 is, for example, located below the energy beam emission section 2. The shaping section 3 has a box-shaped chamber 30. The shaping section 3 includes a plate 31, a lift 32, a powder supply mechanism 33, and a hopper 34 disposed within the chamber 30. The chamber 30 is connected to the support column 26. The internal space of the chamber 30 communicates with the internal space of the support column 26 where the electron gun section 21 is disposed.

[0025] Plate 31 supports the object O to be shaped. The object O is shaped on plate 31. Plate 31 supports the object O being shaped. Plate 31 is, for example, a circular plate. Plate 31 is positioned along the extension line of the emission direction of electron beam B. Plate 31 is, for example, oriented horizontally. Plate 31 is positioned to be supported on a lifting worktable 35 positioned below. Plate 31 and the lifting worktable 35 move together in the vertical direction. Lift 32 is a device that raises and lowers the lifting worktable 35 and plate 31. Lift 32 is electrically connected to control unit 4. Lift 32 receives control signals from control unit 4 and operates accordingly. For example, in the initial stage of shaping object O, lift 32 moves plate 31 upwards together with the lifting worktable 35. Whenever molten and solidified powder material A is deposited on plate 31, lift 32 lowers plate 31. Any mechanism can be used as long as it is a mechanism capable of raising and lowering plate 31.

[0026] Plate 31 is disposed within molding box 36. Molding box 36 is a receiving body located in the lower part of chamber 30. Molding box 36 is formed, for example, in a cylindrical shape. Molding box 36 extends in the direction of movement of plate 31. Molding box 36 is formed in a cross-sectional circular shape concentric with plate 31. Lifting worktable 35 is formed according to the inner shape of molding box 36. When the inner shape of molding box 36 is circular in horizontal cross-section, the outer shape of lifting worktable 35 is also circular. As a result, it is easy to prevent the powder material A supplied to molding box 36 from leaking downwards onto lifting worktable 35. To prevent the powder material A from leaking downwards onto lifting worktable 35, a seal can be provided at the outer edge of lifting worktable 35. The shape of molding box 36 is not limited to cylindrical. The shape of molding box 36 can also be a rectangular tube in cross-section.

[0027] The powder supply mechanism 33 supplies powder material A to the upper part of the plate 31 and smooths the surface of the powder material A. The powder supply mechanism 33 functions as a recoating machine. For example, the powder supply mechanism 33 uses a rod-shaped or plate-shaped component. The powder supply mechanism 33 supplies powder material A to the irradiation area of ​​the electron beam B by moving horizontally and spreads the powder material A evenly. The movement of the powder supply mechanism 33 is controlled by an actuator and mechanism not shown. As a mechanism for smoothing the powder material A, a mechanism other than the powder supply mechanism 33 can be used. The hopper 34 is a receiving container for the powder material A. A discharge port 34a for discharging the powder material A is formed at the lower part of the hopper 34. The powder material A discharged from the discharge port 34a flows onto the plate 31. Alternatively, the powder material A discharged from the discharge port 34a is supplied onto the plate 31 by the powder supply mechanism 33. The plate 31, the elevator 32, the powder supply mechanism 33, and the hopper 34 are disposed within a chamber 30. The chamber 30 is in a vacuum or approximately vacuum state. As a mechanism for supplying powder material A to the plate 31 in layers, a mechanism other than the powder supply mechanism 33 and the hopper 34 can be used.

[0028] The control unit 4 is an electronic control unit that controls the entire 3D modeling device 1. The control unit 4 is configured, for example, as a computer including a CPU, ROM, and RAM. The control unit 4 controls the lifting and lowering of the plate 31, the operation of the powder supply mechanism 33, the emission of the electron beam B, and the operation of the deflection coil 24. For the lifting and lowering control of the plate 31, the control unit 4 operates the elevator 32 by outputting a control signal to it. As a result, the position of the plate 31 in the vertical direction is adjusted. For the operation control of the powder supply mechanism 33, the control unit 4 operates the powder supply mechanism 33 before the electron beam B is emitted. As a result, powder material A is supplied to the plate 31 and spread evenly. For the emission control of the electron beam B, the control unit 4 outputs a control signal to the electron gun 21. As a result, the electron beam B is emitted from the electron gun 21.

[0029] As a means of controlling the operation of the deflection coil 24, the control unit 4 outputs a control signal to the deflection coil 24. As a result, the irradiation position of the electron beam B is controlled. For example, when preheating the powder material A, the control unit 4 outputs a control signal to the deflection coil 24 of the energy beam emission unit 2, thereby scanning the electron beam B onto the plate 31 while irradiating the electron beam B. When shaping the object O, the control unit 4 outputs a control signal to the deflection coil 24 of the energy beam emission unit 2, thereby scanning the electron beam B onto the powder material A on the plate 31 while irradiating the electron beam B.

[0030] Figure 2 This is a view of panel 31 from above. Figure 2 This indicates that electron beam B irradiates powder material A. In Figure 2 In this modeling area, a shaping region M is defined within the area of ​​plate 31. The shaping region M is the area of ​​the cross-section of object O. The shaping region M is the area where electron beam B should be irradiated during the shaping of object O. Arrows within the shaping region M indicate the irradiation path and direction of electron beam B. For example, the irradiation path is set to a straight line. Figure 2 For ease of explanation, the illustration of the powder material A laid on plate 31 is omitted.

[0031] The shaping area M has an outline portion M1 and an inner portion M2. The outline portion M1 is the area near the outline line C of the shaping area M. For example, the outline portion M1 is the area extending inward from the outline line C to a predetermined distance. The outline portion M1 extends along the entire range of the outline line C. The outline portion M1 is the area inside the entire range of the outline line C. However, for the outline portion M1, in cases where there is a convex or concave portion of the outline line C, the predetermined distance of this portion is sometimes changed. For the outline portion M1, in cases where there is a convex or concave portion of the outline line C, the outline portion M1 of that portion is sometimes partially omitted. The inner portion M2 is a central area located inside the shaping area M, closer to the outline portion M1.

[0032] Multiple irradiation paths are set in the contour portion M1 and the inner portion M2. The irradiation pattern of the electron beam B in the contour portion M1 is different from that in the inner portion M2. In the contour portion M1, the irradiation path is set in a direction orthogonal to the contour line C relative to the shaping area M. In the contour portion M1, the electron beam B is irradiated while scanning in a direction orthogonal to the contour line C. That is, multiple irradiation paths are set in the contour portion M1 in a direction orthogonal to the contour line C. As a result, the electron beam B is irradiated sequentially along each irradiation path. At this time, when the contour line C is curved, the scanning direction of the electron beam B is different depending on the irradiation position. That is, when the contour line C is curved, if the energy beam is irradiated sequentially along the irradiation path, the direction of the irradiation path changes. As a result, the scanning direction of the electron beam B changes. In addition, even when the contour line C is curved, the irradiation path is sometimes set so that the directions of adjacent irradiation paths are not changed, and multiple irradiation paths are parallel.

[0033] In contrast, in the inner portion M2, an irradiation path is set along a specific direction. As a result, the electron beam B is irradiated while being scanned along this specific direction. For example, in the inner portion M2, the irradiation path is set along the X direction of the XY coordinate system set on plate 31. As a result, the electron beam B is irradiated while being scanned along this irradiation path. In the inner portion M2, the electron beam B is scanned while being moved back and forth along a specific direction. As a result, the electron beam B can be irradiated in a short time. In the contour portion M1, the electron beam B is also scanned while being moved back and forth in a direction orthogonal to the contour line C. As a result, the electron beam B can be irradiated in a short time.

[0034] exist Figure 2In the contour portion M1, electron beam B scans along a direction orthogonal to the contour line C of the shaping area M. As a result, electron beam B is repeatedly irradiated along a direction orthogonal to the contour line C. The orthogonal direction also includes approximately orthogonal directions. For example, electron beam B may scan at a 90-degree angle relative to the contour line C. Electron beam B may also scan within an angle range of 45 to 135 degrees relative to the contour line C. Even when irradiated in a approximately orthogonal direction, electron beam B can be irradiated for a short time by sequentially scanning along parallel or approximately parallel directions.

[0035] Here, we assume that the electron beam B is irradiated by moving the irradiation position along the contour line C in the contour portion M1. In this case, it is difficult to scan the electron beam B while simultaneously reciprocating it. When shaping the contour portion M1 by irradiating the electron beam B parallel to the contour line C, the energy beam condition prioritizing the surface roughness of the object O is used instead of the irradiation speed priority energy beam condition. In this case, the electron beam B is irradiated while moving at a low speed parallel to the contour line C. Therefore, irradiating the contour portion M1 with the energy beam takes a long time. As a result, the object O cannot be shaped efficiently. For the inner portion M2, it is necessary to change the intensity or irradiation movement speed of the electron beam B in the contour portion M1. Therefore, the change in irradiation control results in a time loss, thus making it impossible to shape the object O efficiently.

[0036] In contrast, the three-dimensional modeling apparatus 1 disclosed herein scans an electron beam B along a direction orthogonal to the contour line C of the modeling region M in the contour portion M1. As a result, the irradiation of the electron beam B into the contour portion M1 can be completed in a short time. The electron beam B can be irradiated into the inner portion M2 without changing its intensity and scanning speed. As a result, the modeling of the object O can be performed efficiently. At this time, the intensity and scanning speed of the electron beam B irradiating the contour portion M1 are the same as those of the electron beam B irradiating the inner portion M2. "Same intensity and scanning speed" also includes approximately the same intensity and scanning speed. That is, as long as the intensity and scanning speed are approximately the same to the extent that changes in irradiation control will hardly cause time loss, the object O can be modeled efficiently.

[0037] Figure 3 This illustrates an example of irradiation by electron beam B. Irradiation of the contour portion M1 by electron beam B can also be performed sequentially along adjacent irradiation paths after irradiation along the irradiation path. For example... Figure 3As shown, the irradiation of the contour portion M1 by electron beam B can also proceed by irradiating electron beam B along an adjacent irradiation path after irradiating electron beam B along the irradiation path. This type of irradiation is called "interlaced scanning". Figure 3 The diagram illustrates the case where the electron beam B is irradiated across two irradiation paths. Furthermore, the number of irradiation paths traversed can be more than two. That is, irradiation of the electron beam B along the entire irradiation path set on the contour portion M1 can be completed by using interlaced scanning. With such electron beam B irradiation, by irradiating the electron beam B along the irradiation path, a suitable time delay can be generated from the melting of the powder material A to the melting of the powder material A in the adjacent irradiation path. As a result, the surface roughness of the shaped object O can be improved. That is, according to interlaced scanning, energy beams are irradiated across mutually separated irradiation paths. As a result, since heat is dispersed, the object O can be properly shaped. Especially in the strip-shaped contour portion M1, when scanning the electron beam B along the width direction of the contour portion M1, heat tends to concentrate due to the irradiation of the electron beam B. In contrast, according to interlaced scanning, heat concentration can be suppressed. Therefore, the object O can be properly shaped.

[0038] Figure 4 This illustrates a variation of irradiation by electron beam B. Figure 2 In the contour portion M1, the illumination path is reversed to illuminate the adjacent illumination path. For example... Figure 4 As shown, the illumination direction can also be unified to the same direction throughout the entire illumination path. For example, as... Figure 4 As shown, the irradiation of electron beam B can also be directed inward from the contour line C for each irradiation path of the contour portion M1. In this case, after irradiating the energy beam along a certain irradiation path, it does not turn back but immediately begins irradiating the energy beam for the next irradiation path. After returning to the contour line C, it begins irradiating the energy beam for the next irradiation path. As a result, heat concentration at the irradiation point can be avoided. In addition, a suitable time delay can be generated from when the powder material A is melted by irradiation of electron beam B along the irradiation path until when the powder material A is melted by irradiation of electron beam B along the adjacent irradiation path. As a result, the surface roughness of the shaped object O can be improved. That is, the irradiation of the energy beam along the adjacent irradiation path is not performed immediately. Therefore, since the heat is dispersed, the object O can be shaped appropriately. Furthermore, in Figure 4 In this case, electron beam B irradiates from the outside towards the inside near the contour line C. Electron beam B can also irradiate from the inside towards the outside towards the contour line C. For example... Figure 3As shown, interlaced scanning can also be used for irradiation of the electron beam B. Particularly in the strip-shaped contour portion M1, when scanning the electron beam B along the width direction of the contour portion M1, heat tends to concentrate due to the irradiation of the electron beam B. In contrast, by making the irradiation direction of the electron beam B the same, heat concentration can be suppressed. As a result, the object O can be appropriately shaped.

[0039] like Figure 4 As shown, an idle time can also be set from the moment powder material A melts by irradiating electron beam B along the irradiation path until the moment powder material A melts by irradiating electron beam B along the next irradiation path. The idle time refers to the time during which powder material A is considered to have not been substantially irradiated by electron beam B. For example, in... Figure 4 In this process, during the idle time, the output of electron beam B is stopped while scanning the path indicated by the dashed line. Alternatively, during the idle time, the focus of electron beam B is shifted while scanning the path indicated by the dashed line. As a result, the energy received by powder material A is substantially reduced, and therefore it can be considered as not being properly irradiated by electron beam B. This idle time is set based on the degree of heat concentration caused by the irradiation of electron beam B. In this way, by setting an idle time for the irradiation of electron beam B, heat can be dispersed. As a result, the object O can be properly shaped. Furthermore, in Figure 4 In this process, after the powder material A is melted by irradiating the electron beam B along the irradiation path, the electron beam B is irradiated along an adjacent irradiation path. For example, the electron beam B can also be irradiated along other irradiation paths, bypassing adjacent irradiation paths.

[0040] exist Figure 1 In this process, when shaping an object O, the control unit 4 uses, for example, 3D CAD (Computer-Aided Design) data of the object O to be shaped. The 3D CAD data of object O is the pre-input shape data of object O. The control unit 4 generates 2D slice data based on the 3D CAD data. The slice data is, for example, data of the horizontal cross-section of the object O to be shaped. The slice data is a collection of multiple data corresponding to the upper and lower positions. Based on the slice data, the control unit 4 sets the shaping area M for irradiating the powder material A with electron beam B. Furthermore, the control unit 4 sets the outline portion M1 and the inner portion M2. The control unit 4 sets the irradiation path and irradiation direction in the outline portion M1 and the inner portion M2. The shaping area M, the outline portion M1, the inner portion M2, the irradiation path, and the irradiation direction are set according to each slice data.

[0041] When shaping object O, control unit 4 outputs a control signal to deflection coil 24 based on setting data including the shaping area M, the outline portion M1, the inner portion M2, the irradiation path, and the irradiation direction. That is, control unit 4 outputs a control signal to deflection coil 24 of energy beam emission unit 2. As a result, electron beam B is irradiated onto the shaping area M corresponding to the shape of the object.

[0042] Next, the operation of the three-dimensional modeling device 1 disclosed herein and the three-dimensional modeling method will be explained.

[0043] Figure 5 This is a flowchart illustrating the operation of the three-dimensional modeling device 1 and the three-dimensional modeling method of this disclosure. Figure 5 A series of control processes are performed, for example, by control unit 4.

[0044] First, such as Figure 5 As shown in step S10, the position of plate 31 is set. Hereinafter, step S10 will be simply referred to as "S10". The following steps are the same. At the beginning of shaping object O, the position of plate 31 is set at the top. Then, as the shaping of object O progresses, the position of plate 31 gradually moves downwards. Figure 1 In this system, the control unit 4 activates the elevator 32 by outputting a working signal to the elevator 32. As a result, the elevator 32 operates, causing the work platform 35 and the plate 31 to rise and fall. Consequently, the position of the plate 31 is set.

[0045] Processing moved to Figure 5 S12. In S12, powder material A is supplied. The supply of powder material A involves supplying powder material A to the irradiation region R of the electron beam B and spreading the powder material A evenly. For example, in... Figure 1 In this configuration, the control unit 4 activates the powder supply mechanism 33 by outputting a working signal to an actuator (not shown). As a result, the powder supply mechanism 33 moves horizontally, supplying powder material A onto the plate 31 and spreading the powder material A evenly.

[0046] Processing moved to Figure 5S14. In S14, a preheating process is performed. The preheating process is the process of preheating the powder material A before molding the object O. Preheating is also called preheating. Preheating is the process of heating the powder material A at a temperature lower than the melting point of the powder material A before molding the object O. By preheating, the powder material A is heated, thereby performing pre-sintering. As a result, the accumulation of negative charge in the powder material A caused by the irradiation of the electron beam B can be suppressed. Therefore, the phenomenon of smoke caused by the powder material A flying due to the scattering of the powder material A during the irradiation of the electron beam B can be suppressed. The control unit 4 outputs a control signal to the energy beam emission unit 2, the electron beam B is emitted from the electron gun unit 21, and the deflection coil 24 is activated. As a result, the irradiation position of the electron beam B is controlled. Thus, as Figure 2 As shown, the powder material A on plate 31 was irradiated with electron beam B, and as a result, the powder material A was heated.

[0047] Then, processing is moved to Figure 5 S16. In S16, which is an irradiation process, an irradiation process is performed. The irradiation process is a shaping process of an object O by irradiating a shaping area M with an electron beam B. For example, the control unit 4 generates two-dimensional slice data based on the three-dimensional CAD data of the object O to be shaped. Based on the slice data, the control unit 4 determines the shaping area M, the outline portion M1, the inner portion M2, the irradiation path, and the irradiation direction for irradiating the powder material A with the electron beam B. The control unit 4 irradiates the electron beam B from the energy beam emission unit 2 according to the set irradiation path and irradiation direction. In the irradiation process of S16, a portion of the layers constituting the object O is shaped.

[0048] Specifically, such as Figure 2 As shown, a shaping region M is defined within the area of ​​plate 31. Next, an outline portion M1 and an inner portion M2 are defined within the shaping region M. Then, the irradiation path and irradiation direction of the electron beam B are defined in the outline portion M1 and the inner portion M2, respectively. As described above, the irradiation patterns of the electron beam B in the outline portion M1 and the inner portion M2 are different. That is, in the outline portion M1, the electron beam B is irradiated by scanning the electron beam B in a direction orthogonal to the outline line C of the shaping region M. On the other hand, in the inner portion M2, the electron beam B is irradiated by scanning the electron beam B along a certain direction. Figure 2The diagram illustrates the case where electron beam B is irradiated by scanning along the X direction of the XY coordinate system set on plate 31. In the contour portion M1 and the inner portion M2, adjacent irradiation paths are parallel or substantially parallel. Therefore, electron beam B can be scanned reciprocally. As a result, the irradiation time of electron beam B can be shortened. Irradiation of electron beam B can be performed without changing the scanning speed from the contour portion M1 to the inner portion M2. Therefore, since electron beam B can be irradiated efficiently, irradiation processing can be performed in a short time.

[0049] In this irradiation process, in the contour portion M1, it is also possible to... Figure 3 The electron beam B is then irradiated by interlacing the irradiation path. Alternatively, it can be done as follows: Figure 4 That way, the electron beam B is irradiated in the same direction.

[0050] Then, processing is moved to Figure 5 S18. In S18, it is determined whether the termination condition of the control process is met. The termination condition of the control process is met, for example, when the modeling of the desired three-dimensional object O is completed. That is, when the modeling of object O is completed as a result of the repeated control processes from S10 to S16. On the other hand, the termination condition of the control process is not met, for example, when the modeling of the desired three-dimensional object O is not completed.

[0051] If the control processing termination condition is not met in S18, the process returns to S10. Conversely, if the control processing termination condition is met in S18, Figure 5 The series of control processes have ended.

[0052] Through repeated practice Figure 5 In the processes from S10 to S18, the molten and solidified powder material A is layered, thus slowly forming object O. Then, the desired object O is finally shaped.

[0053] In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, the electron beam B is used to irradiate the powder material A by scanning the outline portion M1 of the modeling region M in a direction orthogonal to the outline line C of the modeling region M. As a result, the object O can be modeled while the electron beam B is being scanned at high speed. Therefore, the irradiation of the outline portion M1 of the modeling region M by the energy beam can be completed in a short time. Consequently, the object O can be modeled efficiently in a short time. Therefore, the object O can be modeled efficiently.

[0054] In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, the electron beam B can be irradiated with the same intensity and scanning speed at both the contour portion M1 and the inner portion M2. Therefore, the intensity and scanning speed of the electron beam B can be maintained at both the contour portion M1 and the inner portion M2. Thus, the modeling of the object O can be performed efficiently.

[0055] In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, a well-modeled object O can be created. For example, compared to the case where an energy beam is irradiated onto the contour portion M1 parallel to the contour line C, a well-modeled object O with low surface roughness can be created.

[0056] Specifically, examples of modeling an object O are shown. In the three-dimensional modeling apparatus 1, three-dimensional modeling method, and comparative example of this disclosure, an object O with a contour portion M1 having a width of 4 mm is modeled. Then, the surface roughness of the object O modeled by each method is compared. In the three-dimensional modeling apparatus 1 and three-dimensional modeling method of this disclosure, an energy beam is irradiated in a direction orthogonal to the contour line C. In the comparative example, an energy beam is irradiated in a direction parallel to the contour line C. The contour portion M1 with a width of 4 mm indicates that the distance from the contour line C is 4 mm. The arithmetic mean height is used as the surface roughness. The arithmetic mean height Sa is measured by an optical measuring instrument. A laser beam is used as the energy beam. In the three-dimensional modeling apparatus 1 and three-dimensional modeling method of this disclosure, an object O with a surface roughness of approximately Sa = 20 μm can be modeled. In contrast, in the comparative example where the energy beam is irradiated in a direction parallel to the contour line C, only an object O with a surface roughness of approximately Sa = 30 μm can be modeled. In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, the laser current value was set to 28 mA for modeling. In contrast, in a comparative example where the energy beam was irradiated in a direction parallel to the contour line C, the value of Sa decreased when the laser current value was reduced. However, in the comparative example, even when the laser current value was reduced to 10 mA, Sa remained around 28 μm. Thus, it can be seen that the three-dimensional modeling apparatus 1 and three-dimensional modeling method of this disclosure can model well-formed objects O with low surface roughness.

[0057] Furthermore, in the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, electron beam B can be irradiated onto powder material A while simultaneously scanning along a certain direction at an inner portion M2 within the modeling region M, which is located inside the contour portion M1. By irradiating powder material A with electron beam B while scanning along a certain direction at the inner portion M2, energy beam irradiation in the inner portion M2 can be performed in a short time. As a result, the modeling of object O can be performed in a short time.

[0058] In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, electron beam B can also be irradiated along the irradiation path set on the contour portion M1. In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, electron beam B can also be irradiated across an irradiation path adjacent to the irradiation path that has been irradiated. In this case, electron beam B is irradiated across an irradiation path adjacent to the irradiation path that has been irradiated. As a result, heat concentration caused by electron beam B irradiation can be suppressed. Therefore, inappropriate modeling of the object O can be suppressed. In particular, when electron beam B is irradiated along the width direction of the contour portion M1 in the strip-shaped contour portion M1, heat concentration can be suppressed. As a result, appropriate modeling of the object O can be achieved.

[0059] In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, electron beam B can also be used to irradiate the irradiation path set on the contour portion M1. In the three-dimensional modeling apparatus 1 and three-dimensional modeling method disclosed herein, electron beam B can also be used to irradiate the irradiation path in the same direction. In this case, electron beam B is irradiated in the same direction along the irradiation path. Therefore, heat concentration caused by electron beam B irradiation can be suppressed. As a result, inappropriate modeling of the object O can be suppressed. In particular, when electron beam B is irradiated along the width direction of the contour portion M1 in the strip-shaped contour portion M1, heat concentration can be suppressed. Therefore, appropriate modeling of the object O can be achieved.

[0060] As described above, the three-dimensional modeling apparatus 1 and the three-dimensional modeling method of this disclosure have been explained. The three-dimensional modeling apparatus 1 and the three-dimensional modeling method of this disclosure are not limited to the embodiments described above. The three-dimensional modeling apparatus 1 and the three-dimensional modeling method of this disclosure can be modified in various ways without departing from the spirit of the claims.

[0061] For example, the case of shaping an object O by irradiating powder material A with an electron beam B as an energy beam has been described. It is also possible to irradiate powder material A with an energy beam different from the electron beam B. For example, object O can also be shaped by irradiating powder material A with a laser beam as an energy beam. In this case, the object O can be shaped using a device such as a laser scanning head, which can irradiate the powder material A with a laser beam, as the energy beam emission unit 2.

[0062] The case where an inner portion M2 is set inside the outline portion M1 in the modeling area M is explained. The setting of the inner portion M2 can also be omitted. For example, after setting only the outline portion M1 in all or part of the modeling area M, the object O can be modeled by illumination processing. Specifically, as... Figure 6As shown, when the shaping area M is annular or has a strip-shaped area, the inner portion M2 can be omitted, and only the outline portion M1 can be set before energy beam irradiation. Even in this case, the same effect as the above-described embodiment can be obtained.

[0063] During the period when an energy beam is irradiated along an irradiation path, one or both of the scanning speed and intensity of the energy beam can be varied. For example, as... Figure 7 As shown, depending on the angle between the contour and the Z-direction (layering direction), one or both of the scanning speed and intensity of the energy beam can be varied during the period of irradiation along an irradiation path. At the protruding portions of object O, the heat dissipation path is limited. As a result, excess heat is easily generated in the model. In such portions, either the scanning speed of the energy beam can be increased, or the intensity of the energy beam can be decreased. This suppresses heat concentration and thus achieves optimization.

[0064] Explanation of reference numerals in the attached figures:

[0065] 1…3D modeling device; 2…energy beam emission unit; 3…modeling unit; 4…control unit; 21…electron gun unit; 22…aberration coil; 23…focusing coil; 24…deflection coil; 31…plate; 32…elevator; 33…powder supply mechanism; 34…hopper; A…powder material; B…electron beam; C…outline; M…modeling area; M1…outline part; M2…inner part; O…object.

Claims

1. A three-dimensional modeling device, which shapes a three-dimensional object by irradiating the modeling material with an energy beam to melt and layer the material, characterized in that, It has an energy beam emission section that emits the energy beam and irradiates the shaping material with the energy beam. The energy beam emitting unit scans and irradiates the shaping material with the energy beam in a direction orthogonal to the contour line of the shaping region at least the outline portion of the object's cross-section, thereby shaping the object's at least the outline portion. The styling area has the outline portion and an inner portion formed inside the outline portion. The outline portion is the area extending inward from the outline line to a predetermined distance, and the outline portion extends along the entire range of the outline line.

2. The three-dimensional modeling device according to claim 1, characterized in that, The energy beam emitting part is located on the inner side, and the energy beam scans and irradiates the shaping material along a certain direction.

3. The three-dimensional modeling device according to claim 1 or 2, characterized in that, The energy beam emitting unit irradiates multiple irradiation paths set on the contour portion with the energy beam, and after irradiating the irradiation path with the energy beam, it irradiates other irradiation paths by crossing adjacent irradiation paths.

4. The three-dimensional modeling device according to claim 1 or 2, characterized in that, The energy beam emitting unit irradiates multiple irradiation paths set on the contour portion with the energy beam. After irradiating the irradiation path with the energy beam, an idle time is set, and the energy beam is irradiated on other irradiation paths, or the energy beam is irradiated on the adjacent irradiation paths, bypassing the adjacent irradiation paths.

5. The three-dimensional modeling device according to claim 1 or 2, characterized in that, The energy beam emitting unit irradiates multiple irradiation paths set on the contour portion with the energy beam, and irradiates the multiple irradiation paths in the same direction.

6. A three-dimensional modeling method, characterized in that, an energy beam is irradiated onto the modeling material to melt and layer it, thereby creating a three-dimensional object, wherein... This includes the process of emitting the energy beam and irradiating the shaping material with the energy beam. In the irradiation process, the energy beam is scanned in a direction orthogonal to the contour line of the shaping region, at least the outline portion of the object's cross-section, to irradiate the shaping material, thereby shaping the at least outline portion of the object. The styling area has the outline portion and an inner portion formed inside the outline portion. The outline portion is the area extending inward from the outline line to a predetermined distance, and the outline portion extends along the entire range of the outline line.

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