Lamination molding method, lamination molding device, and method for manufacturing lamination-molded article

Abstract

This lamination molding method includes a first flux application step, a first flux solidification step, a first lamination step, and a second lamination step. In the first flux application step, liquid flux is applied to a base material of an iron-containing metal. In the first flux solidification step, the liquid flux applied to the base material is heated to form a first flux layer in which the liquid flux is solidified. In the first lamination step, a first flux layer and a first wire, which is made of an aluminum-containing metal and is supplied onto the first flux layer, are irradiated with a laser beam, and a first aluminum-containing metal layer obtained by melting and solidifying the first flux layer and the first wire is laminated. In the second lamination step, after the first aluminum-containing metal layer is formed, a second wire, which is made of an aluminum-containing metal and is supplied onto a foundation layer, is irradiated with a laser beam, and one or more second aluminum-containing metal layers obtained by melting and solidifying the second wire are laminated.

Description

Layered manufacturing method, layered manufacturing device, and method for manufacturing layered manufactured object

[0001] The present disclosure relates to an additive manufacturing method, an additive manufacturing device, and a method for manufacturing an additive manufactured object, in which a metal material different from the base material is layered on the surface of the metal base material to manufacture a three-dimensional additive manufactured object.

[0002] In order to obtain a composite structure using dissimilar materials, dissimilar material joining is required. Taking a composite structure of an aluminum-based material and an iron-based material as an example, a very brittle Al-Fe intermetallic compound is generated at the joining interface between the two. If this Al-Fe intermetallic compound is formed thickly at the joining interface, it significantly reduces the strength of the joining interface. For this reason, the aluminum-based material and the iron-based material must be joined so as not to form a thick Al-Fe intermetallic compound between the aluminum-based material and the iron-based material. However, it has generally been difficult to obtain a three-dimensional composite structure of an aluminum-based material and an iron-based material so as not to form a thick Al-Fe intermetallic compound.

[0003] Patent Document 1 discloses a dissimilar metal joining method for welding an aluminum-based workpiece made of aluminum or an aluminum alloy to an iron-based workpiece. In the dissimilar metal joining method described in Patent Document 1, the iron-based workpiece has a zinc-based coating layer made of zinc or a zinc alloy covering its surface, and the aluminum-based workpiece has a flux layer applied to at least the portion to be joined with the iron-based workpiece. In the dissimilar metal joining method described in Patent Document 1, the aluminum-based workpiece is placed on the torch side, and the two workpieces are overlapped and joined by a fusion welding method. As a result, the heated portion of the aluminum-based workpiece is melted by heat from a heat source, and the flux is also melted. The molten flux is added to the molten portion of the aluminum-based workpiece, and only the zinc-based coating layer on the surface of the iron-based workpiece is removed by a thermal reaction due to the heat of fusion. As a result, the surface of the iron-based workpiece has improved wettability at the molten portion, and the molten aluminum alloy smoothly covers the surface of the iron-based workpiece. This allows the aluminum-based workpiece and the iron-based workpiece to adhere firmly to each other, resulting in a strong interfacial bonding strength.

[0004] International Publication No. 2007 / 058257

[0005] However, the technology described in Patent Document 1 involves joining a plate-shaped iron-based welded material and a plate-shaped aluminum-based welded material by welding. Therefore, when the iron-based welded material is plate-shaped, it is easy to form a zinc-based coating layer on the plate-shaped iron-based welded material. One method for joining different types of metals is an additive manufacturing (AM) method, which produces a three-dimensional additively manufactured object by supplying a wire made of a metal material different from the base material onto the metal base material and melting and solidifying the metal wire and base layer to form a deposited layer. This AM method has a problem in that the technology described in Patent Document 1 cannot be applied. Specifically, when an iron-containing metal base material is manufactured using an AM method, the base material may be manufactured by melting the wire, making it difficult to form a zinc-based coating layer on the surface of the base material as with the technology described in Patent Document 1. Therefore, there has been a need for a technology for joining an iron-based material and an aluminum-based material using an AM method without significantly reducing the strength of the joint interface between the iron-based material and the aluminum-based material.

[0006] The present disclosure has been made in consideration of the above, and aims to provide an additive manufacturing method that can achieve stronger bonding than conventional methods at the joints between dissimilar materials, such as iron-based materials and aluminum-based materials.

[0007] In order to solve the above-mentioned problems and achieve the object, the additive manufacturing method according to the present disclosure includes a first flux application step, a first flux solidification step, a first lamination step, and a second lamination step. The first flux application step applies a liquid flux to a base material made of a metal containing iron. The first flux solidification step heats the liquid flux applied to the base material to form a first flux layer, which is a layer in which the liquid flux has solidified. The first lamination step irradiates a first wire, which is a wire of a metal containing aluminum, supplied on the first flux layer with a laser beam, and the first flux layer, thereby laminating a first aluminum-containing metal layer, which is a layer formed by melting and solidifying the first flux layer and the first wire. The second lamination step, after forming the first aluminum-containing metal layer, irradiates a second wire, which is a wire of a metal containing aluminum, supplied on a base layer with a laser beam, thereby laminating one or more second aluminum-containing metal layers, which are layers formed by melting and solidifying the second wire.

[0008] The additive manufacturing method according to the present disclosure has the effect of achieving stronger bonding than conventional bonding at the joint between dissimilar materials, such as an iron-based material and an aluminum-based material.

[0009]

[0010] Hereinafter, an additive manufacturing method, an additive manufacturing apparatus, and a method for manufacturing an additive manufactured object according to embodiments of the present disclosure will be described in detail with reference to the drawings.

[0011] First Embodiment. FIG. 1 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to a first embodiment. The additive manufacturing apparatus 100 is a machine tool that manufactures a three-dimensional additively manufactured object by adding molten material to a workpiece. Hereinafter, the vertical direction is referred to as the Z-axis direction, and two mutually orthogonal directions in a plane perpendicular to the Z-axis direction are referred to as the X-axis direction and the Y-axis direction. In the first embodiment, the beam is a laser beam L. The material is a metal wire W. Specifically, the metal wire W is an aluminum-containing metal wire W, such as aluminum or an aluminum alloy wire W. In one example, the metal wire W is a wire W made of an aluminum-magnesium 5000-series aluminum alloy, an aluminum-silicon 4000-series aluminum alloy, or an aluminum-magnesium-silicon 6000-series aluminum alloy. Hereinafter, a material made of a metal containing aluminum will be referred to as an aluminum-based material, and an aluminum-containing metal wire W will also be referred to as an aluminum-based wire.

[0012] The additive manufacturing device 100 forms a deposit 55 by stacking layers of parallel unit beads, which are solidified molten material, to manufacture a three-dimensional additively manufactured object. The additively manufactured object refers to the deposit 55 after the addition of material according to a processing program has been completed. The additive manufacturing device 100 forms the deposit 55 on the base material 51.

[0013] The additive manufacturing device 100 includes a stage 11, a processing head 12, a laser oscillator 13, a fiber cable 14, a gas supply device 15, piping 16, a wire spool 17, a rotary motor 18, a head drive device 19, a rotation mechanism 20, and a control device 21.

[0014] The stage 11 is used to place a base material 51, which serves as a foundation for forming the deposit 55. In the example shown in FIG. 1 , the base material 51 is a plate material made of a metal containing iron. In one example, the base material 51 is made of austenitic stainless steel, an iron alloy containing chromium and nickel. Hereinafter, materials made of metal containing iron will be referred to as iron-based materials. While FIG. 1 shows the base material 51 as a plate material, this is merely an example, and the base material 51 may be made of a material other than a plate material. In one example, the base material 51 may be a workpiece formed by stacking unit beads formed by melting and solidifying wire made of an iron-based material. In the following description, the term "workpiece" refers to the object on which unit beads, which are solidified molten material, are formed, and refers to the base material 51 or the base material 51 on which the deposit 55 is formed.

[0015] The processing head 12 supplies a metal wire W to a processing point, which is an irradiation position of the laser beam L, and irradiates the laser beam L and sprays a shielding gas G. The processing head 12 is movable relative to the stage 11. The processing head 12 has a beam nozzle 121, a wire nozzle 122, and a gas nozzle 123. The beam nozzle 121 emits the laser beam L toward the processing point. The laser beam L is a heat source that melts the wire W at the processing point. The wire nozzle 122 advances the wire W toward the processing point. The gas nozzle 123 sprays a shielding gas G toward the processing point. An example of the shielding gas G is an inert gas such as nitrogen or argon. By spraying the shielding gas G, the additive manufacturing apparatus 100 suppresses oxidation of the deposit 55 and cools the layer formed on the workpiece. The beam nozzle 121, the wire nozzle 122, and the gas nozzle 123 are fixed to the processing head 12, and thereby their positional relationships are uniquely determined. In other words, the relative positions of the beam nozzle 121, the wire nozzle 122, and the gas nozzle 123 are fixed.

[0016] The laser oscillator 13 is a beam source that emits a laser beam L, such as a solid-state laser, gas laser, fiber laser, or semiconductor laser. The fiber cable 14 is an optical transmission path that propagates the laser beam L from the laser oscillator 13 to the beam nozzle 121 of the processing head 12. The fiber cable 14 connects the laser oscillator 13 and the processing head 12. The laser oscillator 13, the fiber cable 14, and the beam nozzle 121 of the processing head 12 constitute an irradiation unit that irradiates the workpiece with the laser beam L that melts the wire W.

[0017] The gas supply device 15 supplies the shielding gas G to the gas nozzle 123 through the piping 16. The piping 16 is connected between the gas supply device 15 and the gas nozzle 123 of the processing head 12, and serves as a flow path for flowing the shielding gas G from the gas supply device 15 to the gas nozzle 123. The gas supply device 15, the piping 16, and the gas nozzle 123 of the processing head 12 constitute a gas supply unit that sprays the shielding gas G toward the processing point.

[0018] The wire spool 17 is a supply source of material, specifically, aluminum-based material, and has wire W wound thereon. The rotary motor 18 rotates the wire spool 17 around its rotation axis. An example of the rotary motor 18 is a servo motor. When the rotary motor 18 is driven, the wire spool 17 rotates, and the wire W is unwound from the wire spool 17. The wire W unwound from the wire spool 17 is passed through a wire nozzle 122 and supplied to a processing point. Furthermore, by rotating the rotary motor 18 in a direction opposite to that for unwounding the wire W from the wire spool 17, the wire W supplied to the processing point can be pulled out from the processing point. In this case, a portion of the wire W unwound from the wire spool 17 on the wire spool 17 side is wound onto the wire spool 17. The wire spool 17, the rotary motor 18, and the wire nozzle 122 of the processing head 12 constitute a material supply unit that supplies material to the workpiece.

[0019] The wire nozzle 122 may be provided with an operating mechanism for pulling out the wire W from the wire spool 17. The additive manufacturing device 100 is provided with at least one of the rotary motor 18 and the operating mechanism for the wire nozzle 122, thereby enabling the wire W to be supplied to the processing point. The operating mechanism for the wire nozzle 122 is not shown in FIG. 1 .

[0020] The head driving device 19 moves the processing head 12 in each of the X-axis, Y-axis, and Z-axis directions. The head driving device 19 includes a servo motor constituting an operating mechanism for moving the processing head 12 in the X-axis direction, a servo motor constituting an operating mechanism for moving the processing head 12 in the Y-axis direction, and a servo motor constituting an operating mechanism for moving the processing head 12 in the Z-axis direction. The head driving device 19 is an operating mechanism that enables translational motion in each of the three axes. The servo motors are not shown in FIG. 1 . The additive manufacturing apparatus 100 can move the irradiation position of the laser beam L on the workpiece by moving the processing head 12 with the head driving device 19. The additive manufacturing apparatus 100 may move the irradiation position of the laser beam L on the workpiece by moving the stage 11 or by moving both the head driving device 19 and the stage 11.

[0021] 1, a laser beam L is emitted from a beam nozzle 121 in the Z-axis direction. The wire nozzle 122 is provided at a position separated from the beam nozzle 121 in the XY plane, and advances the wire W in a direction oblique to the Z-axis. Note that the wire nozzle 122 may advance the wire W in a direction parallel to the Z-axis by being fixed in the processing head 12 toward the Z-axis direction. The wire nozzle 122 limits the advancement of the wire W so that the wire W is supplied to a desired position.

[0022] In the processing head 12 shown in FIG. 1 , the gas nozzle 123 is provided coaxially with the beam nozzle 121 on the outer periphery of the beam nozzle 121 in the XY plane, and injects shielding gas G along the central axis of the laser beam L emitted from the beam nozzle 121. That is, the beam nozzle 121 and the gas nozzle 123 are arranged coaxially with each other. Note that it is sufficient that the shielding gas G is injected into an area including the processing point irradiated with the laser beam L so as not to oxidize the material that melts and solidifies at the processing point. For this reason, the gas nozzle 123 may inject the shielding gas G in a direction oblique to the Z axis. That is, the gas nozzle 123 may inject the shielding gas G in a direction oblique to the central axis of the laser beam L emitted from the beam nozzle 121.

[0023] The rotation mechanism 20 is an operating mechanism that enables the stage 11 to rotate about a first axis and about a second axis perpendicular to the first axis. In the rotation mechanism 20 shown in FIG. 1 , the first axis is an axis parallel to the X-axis, and the second axis is an axis parallel to the Y-axis. The rotation mechanism 20 has a servo motor that constitutes an operating mechanism for rotating the stage 11 about the first axis, and a servo motor that constitutes an operating mechanism for rotating the stage 11 about the second axis. The rotation mechanism 20 is an operating mechanism that enables rotational motion about each of the two axes. The servo motors are not shown in FIG. 1 .

[0024] The additive manufacturing apparatus 100 can change the posture or position of the workpiece by rotating the stage 11 using the rotation mechanism 20. In other words, the additive manufacturing apparatus 100 can move the irradiation position of the laser beam L on the workpiece by rotating the stage 11. By using the rotation mechanism 20, the additive manufacturing apparatus 100 can also manufacture complex shapes, including tapered shapes.

[0025] The control device 21 controls the additive manufacturing device 100 in accordance with a processing program. The control device 21 is, for example, a numerical control device. The control device 21 controls the position of the head driver 19 by outputting a position command to the head driver 19. The control device 21 controls laser oscillation by the laser oscillator 13 by outputting an output command, which is a command according to the beam intensity conditions, to the laser oscillator 13.

[0026] The control device 21 controls the rotary motor 18 by outputting a supply command, which is a command according to a condition of the material supply amount, to the rotary motor 18. The supply command may be a command according to a condition of the wire W supply speed. The supply speed is the speed of the wire W moving from the wire spool 17 to the irradiation position. The supply speed represents the amount of material supplied per hour.

[0027] The control device 21 controls the amount of shielding gas G supplied from the gas supply device 15 to the gas nozzle 123 by outputting a command to the gas supply device 15 according to the conditions of the gas supply amount. The control device 21 controls the drive of the rotation mechanism 20 by outputting a rotation command to the rotation mechanism 20. In other words, the control device 21 controls the entire additive manufacturing apparatus 100 by outputting various commands. The control device 21 controls the material supply unit, irradiation unit, gas supply unit, head drive device 19, and rotation mechanism 20 to cause the additive manufacturing apparatus 100 to form unit beads. The control device 21 corresponds to a control unit.

[0028] Next, a description will be given of the hardware configuration of the control device 21. The functions of the control device 21 are realized by executing a control program, which is a program for executing control of the additive manufacturing apparatus 100, using hardware.

[0029] 2 is a block diagram showing an example of the hardware configuration of a control device included in the additive manufacturing apparatus according to embodiment 1. The control device 21 includes a CPU (Central Processing Unit) 211 that executes various processes, a RAM (Random Access Memory) 212 that includes a data storage area, a ROM (Read Only Memory) 213 that is a non-volatile memory, a storage device 214, and an input / output interface 215 for inputting information to the control device 21 and outputting information from the control device 21. The components shown in FIG. 2 are connected to each other via a bus 216.

[0030] The CPU 211 executes a program stored in the ROM 213 or the storage device 214. The overall control of the additive manufacturing apparatus 100 by the control device 21 is realized using the CPU 211.

[0031] The storage device 214 is a hard disk drive (HDD) or a solid state drive (SSD). The storage device 214 stores control programs and various data. The ROM 213 stores software or programs for controlling hardware, such as a boot loader such as a basic input / output system (BIOS) or a unified extensible firmware interface (UEFI), which is a basic control program for the computer or controller that is the control device 21. The control program may also be stored in the ROM 213.

[0032] The programs stored in the ROM 213 and the storage device 214 are loaded into the RAM 212. The CPU 211 deploys the control programs in the RAM 212 and executes various processes. The input / output interface 215 is an interface for connecting the control device 21 to devices external to the control device 21. A machining program is input to the input / output interface 215. The input / output interface 215 also outputs various commands. The control device 21 may have input devices such as a keyboard and a pointing device, and an output device such as a display.

[0033] The control program may be stored in a computer-readable storage medium. The control device 21 may store the control program stored in the storage medium in the storage device 214. The storage medium may be a portable storage medium such as a flexible disk, or a flash memory such as a semiconductor memory. The control program may be installed in the computer or controller that becomes the control device 21 from another computer or server device via a communication network.

[0034] The functions of the control device 21 may be realized by a processing circuit, which is dedicated hardware for controlling the additive manufacturing device 100. The processing circuit is a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Some of the functions of the control device 21 may be realized by dedicated hardware, and other parts may be realized by software or firmware.

[0035] Next, an additive manufacturing method according to the first embodiment will be described. Note that, since a three-dimensional additively manufactured object is manufactured by the additive manufacturing method, the additive manufacturing method described below also serves as a method for manufacturing an additively manufactured object. Fig. 3 is a flowchart showing an example of the procedure of the additive manufacturing method according to the first embodiment. Figs. 4 to 8 are perspective views schematically showing an example of the procedure of the additive manufacturing method according to the first embodiment.

[0036] Here, an example will be described in which a three-dimensional additively manufactured object is manufactured by an additive manufacturing method by supplying a wire W made of an aluminum-based material onto a base material 51 made of an iron-based material. An example of the base material 51 is a plate made of SUS (Steel Use Stainless) 304, which is a stainless steel. An example of the wire W is a wire made of A5183 specified in Japanese Industrial Standards (JIS) Z 3232. Note that A5183 corresponds to Al5183 specified by the International Organization for Standardization (ISO).

[0037] First, as shown in Fig. 4, a base material 51 made of an iron-based material is prepared (step S11). In the example of Fig. 4, the base material 51 is a plate-shaped member, but it does not have to be a plate-shaped member. In one example, the base material 51 may be manufactured by an additive manufacturing apparatus 100 in which the wire W is made of an iron-based material. Unlike conventional technology, a zinc-based coating layer is not formed on the surface of the base material 51.

[0038] Next, as shown in FIG. 5, a liquid flux 52a is applied to the lamination surface, which is a portion of the surface of the base material 51 (step S12). In one example, commercially available powdered flux and water are mixed in a weight ratio of 1:2 to form the liquid flux 52a. The liquid flux 52a is applied to the lamination surface of the base material 51 using a brush, a spray gun, or other method. Application using a spray gun allows the liquid flux 52a to be applied uniformly to the base material 51. The lamination surface is the surface on which unit beads of the workpiece are formed. Step S12 corresponds to the first flux application step.

[0039] The base material 51 coated with the liquid flux 52a is then transported to a furnace and heated under predetermined heating conditions (step S13). As a result, as shown in FIG. 6, the liquid flux 52a on the base material 51 is dried and solidified, forming a flux layer 52 on the layered surface of the base material 51. In one example, the base material 51 is heated in air at a heating temperature of 100°C for 15 minutes. The base material 51 is then cooled to room temperature. The flux layer 52 corresponds to a first flux layer. Step S13 corresponds to a first flux solidification step.

[0040] The thickness of the flux layer 52 formed by heating is not particularly limited, but a thicker thickness is desirable. In one example, liquid flux 52a can be applied in step S12 so that the flux layer 52 of the desired thickness can be obtained in step S13. In another example, the processes from step S12 to step S13 can be performed multiple times so that the flux layer 52 of the desired thickness can be obtained. Forming the flux layer 52 in multiple steps can improve the uniformity of the flux layer 52.

[0041] Next, the base material 51 on which the flux layer 52 has been formed is placed on the stage 11 of the additive manufacturing apparatus 100 (step S14). Thereafter, as shown in FIG. 7 , the additive manufacturing apparatus 100 irradiates the base material 51 with a laser beam L to melt the wire W and the flux layer 52 supplied onto the flux layer 52, and deposits a first aluminum-containing metal layer 53 on the base material 51 by spreading and solidifying the molten wire W (step S15). That is, the wire W and the flux layer 52 supplied onto the flux layer 52 are irradiated with the laser beam L to melt and solidify the wire W and the flux layer 52, thereby depositing the first aluminum-containing metal layer 53. The laser beam L is supplied to the tip of the wire W. The first aluminum-containing metal layer 53 is formed by arranging a plurality of unit beads in parallel. The wire W used here is a flux-free wire made of a metal containing aluminum. The wire W corresponds to the first wire. The process of step S15 corresponds to the first lamination step.

[0042] The processing in step S15 by the additive manufacturing apparatus 100 will be described in further detail. The base material 51 on which the flux layer 52 has been formed is placed and fixed on the stage 11 of the additive manufacturing apparatus 100. Thereafter, the control device 21 moves the processing head 12 to a position according to the processing program and controls the rotation motor 18 of the wire spool 17 so as to supply the wire W from the wire nozzle 122 to the processing point. The control device 21 also controls the gas supply device 15 to inject shielding gas G from the gas nozzle 123, and controls the laser oscillator 13 to emit the laser beam L from the beam nozzle 121. At this time, the control device 21 controls the output of the laser beam L so as to achieve a temperature lower than the melting point of the iron-based material, at which the flux melts.

[0043] The flux layer 52 is melted by irradiation with the laser beam L. At this time, the base material 51 does not melt. The molten flux removes oxides and the like adhering to the surface of the base material 51. This makes the surface of the base material 51 clean, making it easier to bond with another material, i.e., an aluminum-based material. The molten flux also improves the wettability of the molten wire W, i.e., the molten aluminum-based material, making it easier to bond the underlying base material 51 and the aluminum-based material.

[0044] When the machining head 12 moves and the irradiation position of the laser beam L shifts, the aluminum-based material that was molten at the previous irradiation position of the laser beam L solidifies on the base material 51 to become the first aluminum-containing metal layer 53. At this time, an intermetallic compound layer containing iron and aluminum and having a thickness of 2 μm or less is formed at the interface between the base material 51 and the first aluminum-containing metal layer 53. This thin intermetallic compound layer maintains a strong bond between the base material 51 and the first aluminum-containing metal layer 53.

[0045] Note that unless the intermetallic compound layer is present at the interface between the base material 51 and the first aluminum-containing metal layer 53, they cannot be bonded together. For this reason, an intermetallic compound layer of a certain thickness is necessary. However, if the thickness of the intermetallic compound layer is greater than approximately 2 μm, the metal compound layer will crack and peel when an impact is applied to the additive manufacturing product, resulting in a loss of bonding between the base material 51 and the first aluminum-containing metal layer 53. For this reason, it is desirable that the intermetallic compound layer be 2 μm or less, and even 1 μm or less.

[0046] Furthermore, if the wire W, which is an aluminum-based material, and the base material 51, which is an iron-based material, were to be melted together by irradiation with the laser beam L without the use of flux, an intermetallic compound layer thicker than 2 μm would be formed at the interface. The presence of such an intermetallic compound layer thicker than 2 μm would weaken the bond at the interface between the base material 51 and the first aluminum-containing metal layer 53. For this reason, in the first embodiment, a flux layer 52 having a melting point lower than that of the iron-based material is formed on the base material 51. This allows the flux to melt without melting the iron-based material, thereby allowing the molten aluminum-based material to wet and spread over the iron-based material. Furthermore, because the iron-based material does not melt, excessive reaction with the aluminum-based material is suppressed, and a thin intermetallic compound layer having a thickness of 2 μm or less can be formed at the interface between the base material 51 and the first aluminum-containing metal layer 53.

[0047] In this way, the flux layer 52 is melted without melting the base material 51, and the molten wire W is poured into the molten flux layer 52, thereby improving the wettability of the molten wire W, i.e., the molten aluminum-based material, to the base material 51. As a result, the base material 51 and the first aluminum-containing metal layer 53 are firmly bonded together. Note that, as shown in Fig. 7, in the region not irradiated with the laser beam L, the wire W is not supplied, and therefore the flux layer 52 remains as it is.

[0048] After the first aluminum-containing metal layer 53 is formed, as shown in FIG. 8 , a laser beam L is applied to the base layer to melt and solidify wire W, thereby depositing one or more second aluminum-containing metal layers 54 (step S16). That is, the laser beam L is applied to the wire W supplied onto the base layer, and one or more second aluminum-containing metal layers 54 are deposited on the base layer by melting and solidifying the wire W. In this example, the laser beam L is also applied to the base layer, and the wire W and a portion of the base layer are melted and solidified to deposit the second aluminum-containing metal layer 54. In step S16, a flux layer 52 is not formed on the surface of the base layer on which the first aluminum-containing metal layer 53 is to be deposited before the wire W is applied. This is because the base layer is not a base material 51 made of an iron-based material, and therefore, even if the second aluminum-containing metal layer 54 is formed on the first aluminum-containing metal layer 53, a problematic intermetallic compound layer is not formed. Therefore, in this example, irradiation of the laser beam L melts and solidifies the wire W as well as a portion of the base layer. When the second aluminum-containing metal layer 54 is formed on the first aluminum-containing metal layer 53, the base layer becomes the first aluminum-containing metal layer 53. When the second aluminum-containing metal layer 54 is formed on the second aluminum-containing metal layer 54, the second aluminum-containing metal layer 54 formed immediately before becomes the base layer. The wire W used in step S16 corresponds to the second wire, but is the same as the first wire in the first embodiment. Here, the wire W does not contain flux and is a wire made of a metal containing aluminum. The processing of step S16 corresponds to the second lamination process.

[0049] Then, by repeating the formation of the second aluminum-containing metal layer 54 in step S16 a predetermined number of times, an additive manufacturing method is manufactured.

[0050] In the first embodiment, a liquid flux 52a is applied onto a base material 51 made of an iron-based material, and then the base material 51 is transported into a furnace and heated and dried to form a flux layer 52. The base material 51 is then transported to the additive manufacturing device 100. While a wire W made of an aluminum-based material is supplied onto the base material 51, a laser beam L, the output of which is adjusted to be lower than the melting point of the base material 51 but higher than the melting point of the flux, is irradiated onto the supply position of the wire W. As a result, the flux layer 52 melts without melting the base material 51. The molten wire W flows into the molten flux, causing the wire W, i.e., the aluminum-based material, to wet and spread over the base material 51. By changing the supply position of the wire W and the irradiation position of the laser beam L, the aluminum-based material solidifies, and a first aluminum-containing metal layer 53 is formed on the base material 51. As a result, a strong bond is formed between the base material 51 and the first aluminum-containing metal layer 53. In other words, the additive manufacturing method has the effect of achieving a stronger bond than conventionally possible at the joint between dissimilar materials, such as aluminum-based materials and iron-based materials, which are very difficult to melt and bond.

[0051] Embodiment 2 In Embodiment 1, a liquid flux 52a is applied to a base material 51, the flux is heated and solidified in a furnace to form a flux layer 52, and then the base material 51 is transported to the additive manufacturing device 100 to manufacture a three-dimensional additively manufactured object. For this reason, the base material 51 must be moved in the order of the flux application device, the furnace, and the additive manufacturing device 100. In Embodiment 2, an additive manufacturing method will be described that can laminate an aluminum-based material without melting the base material 51 made of an iron-based material using only the additive manufacturing device 100.

[0052] 9 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to embodiment 2. Note that the same components as those in FIG. 1 are assigned the same reference numerals, and their description will be omitted, and only the parts that differ from FIG. 1 will be described. The additive manufacturing apparatus 100a according to embodiment 2 differs from the additive manufacturing apparatus 100 of embodiment 1 in that it has a supply mechanism for multiple wires W, Wa. That is, in embodiment 2, the additive manufacturing apparatus 100a includes a processing head 12a instead of the processing head 12, and further includes a wire spool 17a and a rotary motor 18a.

[0053] The processing head 12a further includes a wire nozzle 122a in addition to the beam nozzle 121, wire nozzle 122, and gas nozzle 123. The wire nozzle 122a advances the wire Wa toward the processing point. In the ZX plane passing through the center of the processing head 12a, the wire nozzle 122 is disposed in the positive X-axis direction of the beam nozzle 121, and the wire nozzle 122a is disposed in the negative X-axis direction of the beam nozzle 121. Like the wire nozzle 122, the wire nozzle 122a advances the wire Wa toward the irradiation position of the laser beam L on the workpiece. The beam nozzle 121, wire nozzle 122, wire nozzle 122a, and gas nozzle 123 are fixed to the processing head 12a, so that their relative positional relationships are uniquely determined. In other words, the relative positions of the beam nozzle 121, gas nozzle 123, wire nozzle 122, and wire nozzle 122a are fixed.

[0054] The wire spool 17a is a supply source of a material different from the wire W, and has a wire Wa wound thereon. The rotary motor 18a rotates the wire spool 17a around its rotation axis. An example of the rotary motor 18a is a servo motor. When the rotary motor 18a is driven, the wire spool 17a rotates, and the wire Wa is unwound from the wire spool 17a. The wire Wa unwound from the wire spool 17a passes through a wire nozzle 122a and is supplied to the irradiation position of the laser beam L, i.e., the processing point. Furthermore, by rotating the rotary motor 18a in the direction opposite to the direction in which the wire Wa is unwound from the wire spool 17a, the wire Wa supplied to the processing point can be pulled out from the irradiation position of the laser beam L. In this case, a portion of the wire Wa unwound from the wire spool 17a on the wire spool 17a side is wound onto the wire spool 17a. The rotary motor 18a, the wire spool 17a, and the wire nozzle 122a constitute a first material supply unit that supplies material to the workpiece, and the rotary motor 18, the wire spool 17, and the wire nozzle 122 constitute a second material supply unit that supplies material to the workpiece.

[0055] The wire nozzle 122a may be provided with an operating mechanism for pulling out the wire Wa from the wire spool 17a. The additive manufacturing apparatus 100a is provided with at least one of the rotary motor 18a and the operating mechanism for the wire nozzle 122a, thereby enabling the wire Wa to be supplied to the processing point. The operating mechanism for the wire nozzle 122a is not shown in Figure 9.

[0056] In the second embodiment, a wire W made of a metal containing no flux but containing aluminum is wound around the wire spool 17, and a wire made of a metal containing aluminum and flux, i.e., a flux-cored wire Wa, is wound around the wire spool 17a. Hereinafter, the wire Wa will also be referred to as a flux-cored wire Wa. The flux-cored wire Wa corresponds to a flux-containing metal wire, and the wire W corresponds to a metal wire. The wire W is supplied from the wire nozzle 122, and the flux-cored wire Wa is supplied from the wire nozzle 122a. In one example, the wire W is a wire made of a 5000-series aluminum alloy, and the flux-cored wire Wa is a wire containing flux.

[0057] When forming the first aluminum-containing metal layer 53 on the base material 51, the control device 21 controls the first material supply unit to supply a flux-cored wire Wa to the base material 51 on the stage 11, and also controls the irradiation unit to melt and solidify the flux-cored wire Wa by irradiating it with a laser beam L to form the first aluminum-containing metal layer 53. In this way, the first aluminum-containing metal layer 53 is formed on the base material 51. When the formation of the first aluminum-containing metal layer 53 is completed, the control device 21 winds up the flux-cored wire Wa. In addition, the control device 21 controls the second material supply unit to supply a wire W onto the base layer, and also controls the irradiation unit to melt and solidify the wire W by irradiating it with a laser beam L to form one or more second aluminum-containing metal layers 54. In this way, the second aluminum-containing metal layer 54 is formed on the first aluminum-containing metal layer 53.

[0058] Next, an additive manufacturing method according to embodiment 2 will be described. Note that, since a three-dimensional additively manufactured object is manufactured by the additive manufacturing method, the additive manufacturing method described below also serves as a method for manufacturing an additively manufactured object. Fig. 10 is a flowchart showing an example of the procedure of the additive manufacturing method according to embodiment 2.

[0059] Here, an example will be described in which a three-dimensional additively manufactured object is manufactured by an additive manufacturing method by supplying a wire Wa made of an aluminum-based material with flux and a wire W made of an aluminum-based material onto a base material 51 made of an iron-based material. An example of the base material 51 is a plate made of SUS304 stainless steel. An example of the wire W is a wire made of A5183 specified in JIS Z 3232. An example of the wire Wa is a flux-cored wire.

[0060] First, a base material 51 made of an iron-based material is prepared and placed on the stage 11 of the additive manufacturing apparatus 100a (step S31). The base material 51 may or may not be a plate-shaped member. In one example, the base material 51 may be manufactured by the additive manufacturing apparatus 100a using an iron-based wire as the wire W.

[0061] Next, a laser beam L is irradiated to deposit a first aluminum-containing metal layer 53, which is a layer obtained by melting and solidifying the flux-cored wire Wa supplied onto the base material 51 (step S32). That is, the laser beam L is irradiated onto the flux-cored wire Wa supplied onto the base material 51, and the first aluminum-containing metal layer 53 obtained by melting and solidifying the flux-cored wire Wa is deposited on the base material 51. Thus, in step S32, the control device 21 controls the rotation motor 18a of the wire spool 17a and the rotation motor 18 of the wire spool 17 so that the flux-cored wire Wa is supplied onto the base material 51 from the wire nozzle 122a, but the wire W is not supplied from the wire nozzle 122. The first aluminum-containing metal layer 53 may be a single layer, or multiple layers may be laminated. For the fourth and subsequent layers, even if a laser beam L is applied using a normal wire W without a flux-cored wire Wa under irradiation conditions that melt the underlying first aluminum-containing metal layer 53, the heat from the laser beam L is unlikely to be transmitted to the interface between the base material 51 and the first aluminum-containing metal layer 53. Therefore, in one example, the first aluminum-containing metal layer 53 can be formed by stacking one to three unit bead layers. In other words, when the first aluminum-containing metal layer 53 is formed using a flux-cored wire Wa, it is desirable to form one to three unit bead layers formed by melting and solidifying the flux-cored wire Wa. The process of step S32 corresponds to the first stacking step.

[0062] Even when the flux cored wire Wa is melted and solidified on the base material 51, the molten flux cored wire Wa wets and spreads over the base material 51, as in the case of embodiment 1, and the base material 51 and the first aluminum-containing metal layer 53 are firmly joined via an intermetallic compound layer having a thickness of 2 μm or less.

[0063] After the first aluminum-containing metal layer 53 is formed, the flux cored wire Wa is wound up (step S33). That is, the control device 21 controls the rotary motor 18a of the wire spool 17a to rotate in the direction opposite to the direction in which the flux cored wire Wa is fed.

[0064] Thereafter, one or more second aluminum-containing metal layers 54 are laminated by irradiating the wire W supplied onto the base layer with a laser beam L and melting and solidifying the wire W (step S34). That is, the wire W supplied onto the base layer and a portion of the base layer are irradiated with the laser beam L, and one or more second aluminum-containing metal layers 54 are laminated by melting and solidifying the wire W and a portion of the base layer. The processing of step S34 corresponds to a second lamination step.

[0065] Then, by repeating the formation of the second aluminum-containing metal layer 54 in step S34 a predetermined number of times, an additive manufacturing method is manufactured.

[0066] If the amount of flux in the flux cored wire Wa is insufficient in step S31, this may be combined with embodiment 1. In this case, in step S31, the base material 51, on which liquid flux 52a has been applied and dried to form a flux layer 52, is placed on the stage 11 of the additive manufacturing apparatus 100a, and the procedure shown in Fig. 10 is performed. In this case, since the flux layer 52 is formed on the base material 51, even if the amount of flux contained in the flux cored wire Wa is insufficient, a sufficient amount of molten flux can be formed on the base material 51, making it possible to wet and spread the aluminum-based material on the base material 51.

[0067] In one example, it may be difficult to procure a flux-cored wire Wa having the desired composition. In such a case, the first aluminum-containing metal layer 53 may be formed from an aluminum-based material different in composition from the second aluminum-containing metal layer 54. In one example, a flux-cored wire Wa made of an aluminum-based material different in composition from the wire W wound around the wire spool 17a is wound around the wire spool 17a. In one example, when the wire W is a 5000-series aluminum-based wire such as A5183, the flux-cored wire Wa may be a 4000-series flux-cored wire such as A4043 or A4047 specified in JIS Z 3232. When a 4000-series flux-cored wire is used as the flux-cored wire Wa, a ternary intermetallic compound layer containing silicon (aluminum-silicon-iron) is formed at the interface between the base material 51 and the first aluminum-containing metal layer 53.

[0068] In this case, in step S32, a flux-cored wire Wa is used to form a first aluminum-containing metal layer 53 in which unit beads are stacked in parallel in a range of one to three layers. In step S34, a wire W is used to form a second aluminum-containing metal layer 54. Since the first aluminum-containing metal layer 53 has one to three layers, it is very thin compared to the overall thickness of the second aluminum-containing metal layer 54. Therefore, even if there are slight differences in composition, the effect on the additive manufacturing product is small.

[0069] In the second embodiment, a flux-cored wire Wa in which flux is added to an aluminum-based metal is supplied onto a base material 51 made of an iron-based material, and the flux-cored wire Wa is melted and solidified by a laser beam L to form a first aluminum-containing metal layer 53. Thereafter, a wire W made of an aluminum-based material is supplied onto the first aluminum-containing metal layer 53, and the wire W and the underlying first aluminum-containing metal layer 53 are melted and solidified by the laser beam L to form a second aluminum-containing metal layer 54. This, as in the first embodiment, has the effect of realizing a stronger bond than conventionally achieved at the joint between dissimilar materials, that is, an iron-based material and an aluminum-based material, even when using materials that are very difficult to melt and bond by the additive manufacturing method.

[0070] Furthermore, in the second embodiment, it is possible to omit the process of applying the liquid flux 52a onto the base material 51 and then heating it in a furnace to dry and solidify it, which has the effect of shortening the time required to manufacture the layered object compared to the first embodiment.

[0071] Embodiment 3. In Embodiments 1 and 2, after the first aluminum-containing metal layer 53 is formed on the base material 51, a wire W of an aluminum-based material is supplied, melted, and solidified to form the second aluminum-containing metal layer 54. When laminating an aluminum-containing metal layer on an aluminum-containing metal layer, there is no need to worry about the formation of an intermetallic compound layer. However, when forming an aluminum-containing metal layer on an aluminum-containing metal layer, the lower aluminum-containing metal layer must also be melted, so the output of the laser beam L must be increased. If the output of the laser beam L is high, heat is transferred to the first aluminum-containing metal layer 53 on the base material 51. This heat then causes the thin intermetallic compound layer formed between the base material 51 and the first aluminum-containing metal layer 53 to grow and become thicker. If the intermetallic compound layer becomes thicker, it becomes more susceptible to cracking when subjected to an impact on the additive manufacturing product, resulting in a loss of the bond between the base material 51 and the first aluminum-containing metal layer 53. Therefore, an additive manufacturing method that can suppress the output of the laser beam L when forming the second aluminum-containing metal layer 54 will be described.

[0072] 11 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to embodiment 3. The same components as those in FIG. 1 are denoted by the same reference numerals, and their description will be omitted. Only the differences from FIG. 1 will be described. The additive manufacturing apparatus 100b according to embodiment 3 further includes a flux application device 22, an application driving device 23, a flux solidification device 24, and a solidification driving device 25.

[0073] The flux applicator 22 applies a liquid flux 52a to the layered surface of the workpiece placed on the stage 11. In one example, the flux applicator 22 drops or sprays the liquid flux 52a onto the layered surface of the workpiece. The workpiece is a base material 51, a base material 51 on which a first aluminum-containing metal layer 53 is formed, or a base material 51 on which a second aluminum-containing metal layer 54 and a first aluminum-containing metal layer 53 are formed.

[0074] The coating drive device 23 moves the flux coating device 22 in each of the X-axis, Y-axis, and Z-axis directions. The coating drive device 23 includes a servo motor constituting an operating mechanism for moving the flux coating device 22 in the X-axis direction, a servo motor constituting an operating mechanism for moving the flux coating device 22 in the Y-axis direction, and a servo motor constituting an operating mechanism for moving the flux coating device 22 in the Z-axis direction. The coating drive device 23 is an operating mechanism that enables translational motion in each of the three axes. The servo motors are not shown in FIG. 11 . The additive manufacturing apparatus 100b can move the coating position of the liquid flux 52a on the workpiece by moving the flux coating device 22 using the coating drive device 23. The additive manufacturing apparatus 100b may move the coating position of the liquid flux 52a on the workpiece by moving the stage 11 or by moving both the flux coating device 22 and the stage 11. The flux applying device 22 and the application driving device 23 constitute a flux applying section that applies liquid flux 52a.

[0075] The flux solidification device 24 is a device that solidifies the liquid flux 52a applied to the layered surface of the workpiece by applying hot air to the liquid flux 52a. One example of the flux solidification device 24 is a dryer that heats air and blows it onto the layered surface of the workpiece. In another example, the flux solidification device 24 may be a device that solidifies the liquid flux 52a by placing an object whose temperature is equal to or higher than the solidification temperature of the liquid flux 52a close to the liquid flux 52a.

[0076] The solidification drive device 25 moves the flux solidification device 24 in each of the X-axis, Y-axis, and Z-axis directions. The solidification drive device 25 includes a servo motor constituting an operating mechanism for moving the flux solidification device 24 in the X-axis direction, a servo motor constituting an operating mechanism for moving the flux solidification device 24 in the Y-axis direction, and a servo motor constituting an operating mechanism for moving the flux solidification device 24 in the Z-axis direction. The solidification drive device 25 is an operating mechanism that enables translational motion in each of the three axes. The servo motors are not shown in FIG. 11 . The additive manufacturing apparatus 100b can move the flux heating position on the workpiece by moving the flux solidification device 24 using the solidification drive device 25. The additive manufacturing apparatus 100b may move the flux heating position on the workpiece by moving the stage 11 or by moving both the flux solidification device 24 and the stage 11. The flux solidification device 24 and the solidification driving device 25 constitute a heating unit that dries the liquid flux 52a.

[0077] When forming the second aluminum-containing metal layer 54, the control device 21 controls the operation of the flux applicator to apply liquid flux 52a to the lamination surface, which is a portion of the surface of the base layer. The control device 21 also controls the operation of the heater to heat the liquid flux 52a applied to the lamination surface and form a flux layer 52, which is a layer in which the liquid flux 52a is solidified. In this example, after the flux applicator 22 has completed applying the liquid flux 52a, hot air is blown from the flux solidification device 24 onto the liquid flux 52a. The base layer is the layer below which the unit beads are formed, and is the deposit 55 formed immediately before a new deposit 55 is formed. The flux layer 52 formed when forming the second aluminum-containing metal layer 54 corresponds to the second flux layer.

[0078] Although the case where the flux solidification device 24 is a dryer has been exemplified here, the applied liquid flux 52a may be solidified by irradiating the laser beam L onto the applied liquid flux 52a. In this case, the flux solidification device 24 and the solidification driving device 25 are substituted by the beam nozzle 121 and the head driving device 19. The control device 21 controls the laser beam L to be irradiated with an output sufficient to dry the liquid flux 52a while scanning the applied area with the liquid flux 52a.

[0079] Furthermore, when forming the first aluminum-containing metal layer 53 on the base material 51, the flux applicator 22 may apply liquid flux 52a to the base material 51, and the flux solidifier 24 may solidify the liquid flux 52a to form the flux layer 52. In this case, the controller 21 controls the flux applicator to apply the liquid flux 52a to a layering surface, which is a portion of the surface of the base material 51 on the stage 11. The controller 21 controls the heater to heat the liquid flux 52a applied to the base material 51 to form the flux layer 52. The controller 21 controls the material supply unit to supply the wire W onto the flux layer 52, and also controls the irradiator to melt and solidify the wire W and the flux layer 52 by irradiation with the laser beam L, without melting the base material 51, to form the first aluminum-containing metal layer 53. After the first aluminum-containing metal layer 53 is formed, the control device 21 controls the flux application unit to apply liquid flux 52a onto the lamination surface, which is a portion of the surface of the base layer. The control device 21 controls the heating unit to form a flux layer 52, which is a layer obtained by heating and drying the liquid flux 52a applied to the lamination surface. The control device 21 controls the material supply unit to supply wire W onto the flux layer 52, and also controls the irradiation unit to form a second aluminum-containing metal layer 54 by melting and solidifying the wire W and the flux layer 52 by irradiating it with a laser beam L. This eliminates the need to apply liquid flux 52a and dry it to form the flux layer 52 in a location separate from the additive manufacturing device 100, as in the first embodiment, and allows these processes to be performed in the additive manufacturing device 100b.

[0080] Next, an additive manufacturing method according to a third embodiment will be described. Note that, since a three-dimensional additively manufactured object is manufactured by the additive manufacturing method, the additive manufacturing method described below is also a method for manufacturing an additively manufactured object. FIG. 12 is a flowchart showing an example of the procedure of the additive manufacturing method according to the third embodiment. This flowchart shows details of the process for forming the second aluminum-containing metal layer 54 in step S16 of FIG. 3 of the first embodiment or step S34 of FIG. 10 of the second embodiment. In other words, the additive manufacturing method will be described starting from a state in which the first aluminum-containing metal layer 53 has been formed.

[0081] First, the flux applicator 22 applies liquid flux 52a to the lamination surface, which is a part of the surface of the base layer (step S51). That is, the controller 21 controls the flux applicator so that the liquid flux 52a is applied to the base layer. Note that when the second aluminum-containing metal layer 54 is formed first, the base layer becomes the first aluminum-containing metal layer 53. The process of step S51 corresponds to the second flux application step.

[0082] After the application of the liquid flux 52a is completed, the flux solidification device 24 solidifies the liquid flux 52a applied to the lamination surface to form a flux layer 52 (step S52). The liquid flux 52a is solidified by heating and drying. In the example of FIG. 11 , the flux solidification device 24 blows hot air onto the liquid flux 52a on the first aluminum-containing metal layer 53. That is, the control device 21 controls the heating unit so that the hot air from the flux solidification device 24 hits the applied liquid flux 52a. This forms the flux layer 52 in which the liquid flux 52a is solidified. The flux layer 52 formed in step S52 corresponds to the second flux layer. Step S52 corresponds to the second flux solidification process.

[0083] Thereafter, a laser beam L is applied to melt the wire W and the flux layer 52 supplied onto the flux layer 52, and the molten wire W is wetted and spread onto the base layer, thereby forming a second aluminum-containing metal layer 54 (step S53). That is, the wire W and the flux layer 52 supplied onto the flux layer 52 are irradiated with the laser beam L to melt and solidify the wire W and the flux layer 52, thereby forming the second aluminum-containing metal layer 54. At this time, the output of the laser beam L is set to a level sufficient to melt the flux layer 52 without melting the first aluminum-containing metal layer 53 of the base layer. This causes the molten aluminum-based material to flow into the molten flux. The molten aluminum-based material wets and spreads onto the base layer along the molten flux. Then, as the irradiation position of the laser beam L shifts, the wetted and spread aluminum-based material solidifies, forming the second aluminum-containing metal layer 54.

[0084] In this way, there is no need to melt the first aluminum-containing metal layer 53 of the base layer, and it is only necessary to melt the flux layer 52, which has a lower melting point than the first aluminum-containing metal layer 53, so the output of the laser beam L can be reduced compared to the first and second embodiments.

[0085] The above-described processes from step S51 to step S53 are repeatedly performed until the desired number of second aluminum-containing metal layers 54 is formed, thereby manufacturing an additively shaped object. When forming the second or subsequent second aluminum-containing metal layers 54, the base layer is the second aluminum-containing metal layer 54 formed immediately before. After the additively shaped object is manufactured, the process ends.

[0086] Another method for reducing the output of the laser beam L when forming the second aluminum-containing metal layer 54 on the first aluminum-containing metal layer 53 will be described. Figure 13 is a diagram schematically showing another example of the configuration of an additive manufacturing apparatus according to embodiment 3. Note that the same components as those in Figures 1 and 11 are given the same reference numerals, and their description will be omitted, and only the parts that differ from Figures 1 and 11 will be described. The additive manufacturing apparatus 100c further includes a hot wire power supply 26, a current cable 27, and an insulating member 28 in addition to the configuration of Figure 11.

[0087] The hot wire power supply 26 is a power supply that generates a high current to heat the metal wire W to near its melting point. The hot wire power supply 26 passes a current between the wire W and the base material 51. One of the current cables 27 connects the hot wire power supply 26 and the wire nozzle 122. The other current cable 27 connects the hot wire power supply 26 and the base material 51. When a current from the hot wire power supply 26 flows through the current cable 27 to the wire nozzle 122, a current flows in the wire W that is in contact with the wire nozzle 122. This heats the wire W. The insulating member 28 insulates the stage 11 from the base material 51. During the modeling process, a current flows between the wire nozzle 122 and the base material 51, and the insulating member 28 is provided to prevent this current from flowing to members below the stage 11.

[0088] Because the wire W has electrical resistance, Joule heat is generated in the wire W when a current flows through it. The temperature of the wire W rises due to Joule heat. In other words, the wire W is heated by passing a current through it. In the case of FIG. 13 , the laser beam L irradiated onto the wire W and the Joule heat generated in the wire W serve as the heat source for melting the wire W. In the additive manufacturing device 100c, the addition of Joule heat to the heating by the laser beam L promotes melting of the wire W, thereby improving the processing speed. In order to improve the processing speed, it is desirable to heat the wire W to near its melting point by Joule heat. Furthermore, because Joule heat is applied to the wire W, the output of the laser beam L for melting the wire W can be limited. As a result, excessive heat input to the workpiece due to irradiation with the laser beam L is suppressed.

[0089] Furthermore, when the wire W is supplied onto the workpiece, the tip of the wire W comes into contact with the workpiece. If a flux layer 52 is formed, if the wire W is supplied with its tip in contact with the flux layer 52, the hard wire W will scratch the flux layer 52. As a result, there is a possibility that the flux layer 52 will peel off. However, by passing a current through the wire W, the wire W becomes soft due to Joule heat. As a result, even if the wire W is supplied with its tip in contact with the flux layer 52, the wire W is prevented from scratching the flux layer 52, and peeling of the flux layer 52 is suppressed.

[0090] When the wire W is supplied onto the flux layer 52 , the control device 21 controls the hot wire power supply 26 so that a current flows between the wire W and the stage 11 .

[0091] In Figure 13, the additive manufacturing apparatus 100b in Figure 11 is configured to be provided with a hot wire power supply 26, a current cable 27, and an insulating member 28, but the additive manufacturing apparatus 100, 100a in Figure 1 or Figure 9 may also be configured to be provided with a hot wire power supply 26, a current cable 27, and an insulating member 28.

[0092] In the third embodiment, the additive manufacturing apparatuses 100b and 100c further include a flux application device 22 that applies liquid flux 52a, an application driver 23 that drives the flux application device 22, a flux solidification device 24 that solidifies the applied liquid flux 52a, and a solidification driver 25 that drives the flux solidification device 24. This eliminates the need to move the base material 51 to apply the liquid flux 52a when forming the second aluminum-containing metal layer 54. In other words, the additive manufacturing apparatuses 100b and 100c can apply the flux and dry the applied flux without moving the base material 51. As a result, the aluminum-containing metal layer of the underlayer does not need to be melted when forming the second aluminum-containing metal layer 54, allowing the output of the laser beam L to be reduced. Because the output of the laser beam L can be reduced, it is possible to prevent heat generated by irradiation with the laser beam L from being transmitted to the first aluminum-containing metal layer 53, which is the first layer on the base material 51. Because heat is less likely to be transmitted to the first aluminum-containing metal layer 53, growth of the intermetallic compound layer at the interface between the base material 51 and the first aluminum-containing metal layer 53 is suppressed. This makes it possible to prevent the intermetallic compound layer from cracking and thus the loss of the bond between the base material 51 and the first aluminum-containing metal layer 53, even when an impact is applied to the additive manufacturing product.

[0093] Furthermore, if the base material 51 is removed from the stage 11 of the additive manufacturing apparatus 100b, 100c to form the flux layer 52 each time the second aluminum-containing metal layer 54 is formed, misalignment occurs when the base material 51 is placed on the stage 11 again. As a result, the formation position of the second aluminum-containing metal layer 54 also shifts, making it difficult to manufacture an additively manufactured object of the desired shape. However, in the third embodiment, there is no need to remove the base material 51 that has been placed on the stage 11 of the additive manufacturing apparatus 100b, 100c to form the flux layer 52 when forming the second aluminum-containing metal layer 54. Because the base material 51 does not need to be re-placed, an additively manufactured object of the desired shape can be manufactured without misalignment.

[0094] Furthermore, in the third embodiment, a current is passed through the wire W to heat it. This allows the wire W to melt while reducing the output of the laser beam L. In addition, the wire W is softened by Joule heat caused by the current flowing through the wire W, which makes it possible to prevent the tip of the wire W from damaging the flux layer 52 or peeling off the flux layer 52.

[0095] Fourth Embodiment In the third embodiment, an example was given in which the output of the laser beam L is limited by applying a liquid flux 52 a to the lamination surface or by passing a current through the supplied wire W when forming the second aluminum-containing metal layer 54. In the fourth embodiment, a case will be described in which the beam diameter is increased to reduce the energy density of the laser beam L.

[0096] FIG. 14 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to a fourth embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals, and their description will be omitted. Only the differences from FIG. 1 will be described. The additive manufacturing apparatus 100d according to the fourth embodiment further includes a shaping optical system 29 between the fiber cable 14 and the beam nozzle 121 of the processing head 12. The shaping optical system 29 is an element that shapes the profile of the laser beam L output from the fiber cable 14. In one example, the shaping optical system 29 widens the beam diameter of the laser beam L and homogenizes the intensity distribution of the laser beam L. The laser beam L output from the shaping optical system 29 is incident on the beam nozzle 121. In the fourth embodiment, a laser beam L that has been shaped so as to widen the beam diameter of the laser beam L output from the fiber cable 14 and to have a uniform intensity distribution is used.

[0097] A fly-eye lens, an aspherical lens, a diffractive optical element (DOE), a kaleidoscope, a polyhedral prism, etc. can be used as the shaping optical system 29. Also, a scanner such as a galvanometer mirror can be used as the shaping optical system 29.

[0098] A fly's eye lens is an optical element with lenses arranged in an array like a fly's eye. A fly's eye lens can form a beam profile with a uniform intensity distribution. It can also form a rectangular beam profile.

[0099] An aspherical lens is an optical element that has different shapes between its peripheral and central portions, and uses the differences in the focusing characteristics of the laser beam L that passes through each region to form a beam profile with a uniform intensity distribution. For example, an aspherical lens is used to form a circular, uniform beam.

[0100] A diffractive optical element is an optical element that intentionally induces diffraction by forming wavelength-order irregularities on the surface of an optical substrate, thereby forming a circular, rectangular, or linear beam profile with a uniform intensity distribution.

[0101] A kaleidoscope is an optical element that forms a rectangular beam profile with a uniform intensity distribution by combining, for example, four mirrors in a rectangular shape with their mirror surfaces facing inward.

[0102] A polyhedral prism is an optical element that forms a beam profile of a desired shape with a uniform intensity distribution by varying the angle of refraction of the beam at the exit surface relative to the incident light.

[0103] An example of the diameter of the wire W is 1.2 mm. When the shaping optical system 29 is not used, the beam diameter, which is the diameter of the laser beam L, is approximately 3 mm, which is larger than the diameter of the wire W. In the fourth embodiment, the beam diameter is increased to more than 3 mm by the shaping optical system 29. In one example, the beam diameter is 10 mm, and can be further increased to 10 mm or more. Increasing the beam diameter widens the irradiation area of ​​the laser beam L, allowing more wire W to be supplied to this irradiation area. Methods for supplying more wire W to the irradiation area of ​​the laser beam L include increasing the wire W supply speed, feeding multiple wires W, and increasing the diameter of the wire W. The method for increasing the wire W supply speed is achieved by increasing the rotation speed of the rotary motor 18 of the wire spool 17 using the control device 21. The method for feeding multiple wires W is achieved by having the processing head 12 have multiple wire nozzles 122, 122a and simultaneously feeding the same type of wire W and Wa from the multiple wire nozzles 122, 122a, as shown in FIG. 9 of the second embodiment. The diameter of the wire W can be increased by winding the wire W around the wire spool 17 to a thickness greater than that of the wire W used when the shaping optical system 29 is not used.

[0104] If the beam diameter of the laser beam L is increased while maintaining its circular shape, the laser beam L will irradiate portions of the base layer that should not be irradiated. For this reason, it is desirable to convert the circular laser beam L into a rectangular laser beam L using the shaping optical system 29 so that the laser beam L is irradiated only to the portions that should be irradiated. By giving the laser beam L a rectangular beam profile in this way, the laser beam L will be irradiated to the portions that should be irradiated, i.e., the portions that should be melted, and it is possible to improve energy efficiency compared to the case of a circular beam profile.

[0105] 13 of Embodiment 3 may be combined with the mechanism for heating the wire W. When the irradiation area of ​​the laser beam L is larger than the area irradiated on the wire W, the output of the laser beam L per unit area is small, and therefore, a method of supplying the wire W onto the workpiece while heating it is effective for melting the wire W.

[0106] Furthermore, a gas laser, solid-state laser, fiber laser, semiconductor laser, etc. can be used as the laser oscillator 13. However, when expanding the beam diameter in the shaping optical system 29, it is desirable to use a semiconductor laser that outputs a laser beam L with a larger beam diameter than a gas laser, solid-state laser, or fiber laser.

[0107] In the fourth embodiment, the additive manufacturing apparatus 100d includes a shaping optical system 29 that widens the beam diameter of the laser beam L emitted from the laser oscillator 13 and uniforms its intensity. This allows the additive manufacturing apparatus 100d to irradiate a wider area and supply more wire W to the irradiation area. As a result, it is possible to form a wide unit bead in one go, thereby increasing the manufacturing speed. Furthermore, by widening the irradiation area of ​​the laser beam L, the energy density of the laser beam L is reduced. Therefore, even if a laser beam L with the same output as that without the shaping optical system 29 is used, heat is less likely to be transmitted to the first aluminum-containing metal layer 53 in contact with the base material 51. This suppresses the growth of an intermetallic compound layer at the interface between the base material 51 and the first aluminum-containing metal layer 53, resulting in a three-dimensional additive manufacturing object with a strong bond.

[0108] Fifth Embodiment When a laser beam L is irradiated onto a wire W to melt and solidify it to continuously form unit beads, for example, the final part of a single layer may accumulate more heat than the first part. This causes the temperature to rise, resulting in excessive heat input at the end of the forming process of a given layer. If excessive heat input occurs, the heat may be transferred to the first aluminum-containing metal layer 53, which is in contact with the base material 51. In this case, as described above, an intermetallic compound layer may grow at the interface between the base material 51 and the first aluminum-containing metal layer 53. Furthermore, there may be areas of the base layer that are not melted and areas that are melted, potentially resulting in a decrease in processing quality. Therefore, in a fifth embodiment, a case in which excessive heat input is suppressed is described.

[0109] FIG. 15 is a schematic diagram illustrating an example of the configuration of an additive manufacturing apparatus according to a fifth embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals, and their description will be omitted. Differences from FIG. 1 will be described. The additive manufacturing apparatus 100e according to the fifth embodiment further includes a temperature measurement unit 30 that measures the temperature of the processing point, which is the position where the laser beam L is irradiated on the workpiece. An example of the temperature measurement unit 30 is a radiation thermometer that measures the intensity of infrared radiation emitted from the processing point. The radiation thermometer may be mounted inside or outside the processing head 12. If mounted inside the processing head 12, it is desirable to mount it on the same axis as the output of the laser beam L. This allows the temperature to be measured from directly above the processing point, resulting in more accurate temperature measurement. The temperature measurement unit 30 outputs the temperature measurement result of the processing point to the control device 21.

[0110] The control device 21 acquires the temperature measurement value of the processing point from the temperature measurement unit 30, and if the temperature measurement value is higher than a predetermined reference value, controls the laser oscillator 13 to reduce the output of the laser beam L. The predetermined reference value can be the temperature at which the flux layer 52, the first aluminum-containing metal layer 53, or the second aluminum-containing metal layer 54 melts. When the first aluminum-containing metal layer 53 is formed on the base material 51 on which the flux layer 52 has been formed, the laser beam L is initially output so that the processing point has a temperature lower than the melting point of the base material 51 but higher than the melting point of the flux layer 52, which is the predetermined reference value. However, if the laser beam L is continuously irradiated with the same output power, heat accumulates in the workpiece as processing continues, and the temperature of the processing point exceeds the predetermined reference value. In such a case, the control device 21 controls the irradiation unit, i.e., the laser oscillator 13, to reduce the output of the laser beam L so that the temperature of the processing point reaches the predetermined reference value.

[0111] 16 is a flowchart showing an example of the steps of the additive manufacturing method according to embodiment 5. This flowchart shows the process of controlling the temperature of the processing point during the formation of the first aluminum-containing metal layer 53 or the second aluminum-containing metal layer 54. Hereinafter, the first aluminum-containing metal layer 53 and the second aluminum-containing metal layer 54 will be referred to as aluminum-containing metal layers unless they are to be individually distinguished.

[0112] First, the wire W is supplied onto the workpiece, and a laser beam L of a predetermined output power is irradiated onto the workpiece (step S71). That is, the control device 21 controls the material supply unit so that the wire W is supplied to the processing point, and controls the irradiation unit so that the laser beam L of the predetermined output power is irradiated onto the processing point including the tip of the wire W. The predetermined output power is the preset output power of the laser beam L at the start of processing. Furthermore, when the output power of the laser beam L is reduced in step S74 described later, the predetermined output power is the output power of the laser beam L determined in the most recent step S74.

[0113] The temperature measurement unit 30 constantly measures the temperature of the processing point during the modeling process. The control device 21 acquires a temperature measurement value, which is a measurement value of the temperature of the processing point, from the temperature measurement unit 30 (step S72). The control device 21 determines whether the temperature measurement value is higher than a predetermined reference value (step S73). If the temperature measurement value is equal to or lower than the predetermined reference value (No in step S73), the workpiece has not yet accumulated heat due to irradiation with the laser beam L. Therefore, no special control is performed, and the current output of the laser beam L is maintained. The control device 21 determines whether the modeling process has been completed (step S76). If the modeling process has not been completed (No in step S76), the process returns to step S71. If the modeling process has been completed (Yes in step S76), the process ends.

[0114] On the other hand, if the measured temperature value is higher than the predetermined reference value (Yes in step S73), the processing point is irradiated with a laser beam L having an output lower than the current output while the wire W is being supplied to the processing point (step S74). That is, the control device 21 controls the irradiation unit so that the laser beam L is output at an output lower than the current output of the laser beam L. That is, the control device 21 controls the irradiation unit so as to reduce the output of the laser beam L. In one example, the output of the laser beam L is determined in advance so that the difference between the measured temperature value and the predetermined reference value becomes zero, and the output of the laser beam L can be determined based on correspondence information that associates the difference between the measured temperature value and the predetermined reference value with the output of the laser beam L.

[0115] Thereafter, it is determined whether the formation process has been completed (step S75). If the formation process has not been completed (No in step S75), the process returns to step S72. If the formation process has been completed (Yes in step S75), the process ends.

[0116] In the fifth embodiment, the additive manufacturing apparatus 100e further includes a temperature measurement unit 30 that measures the temperature of the processing point. When the temperature measurement value of the processing point measured by the temperature measurement unit 30 is higher than a predetermined reference value, the control device 21 controls the irradiation unit so that the laser beam L is irradiated with a lower output than the current output, i.e., so that the output of the laser beam L is reduced. This makes it possible to appropriately adjust the output of the laser beam L irradiated to the processing point, taking into account heat accumulation at the processing point due to continuous irradiation of the laser beam L.

[0117] Sixth Embodiment The wire W is supplied onto the workpiece, with its tip in contact with the processing point of the workpiece. If the wire W is supplied from the wire spool 17 in this state, it may get caught on an underlying layer such as the flux layer 52, which may cause the flux layer 52 to peel off or damage the underlying layer. Therefore, in the sixth embodiment, a case will be described in which the wire W is prevented from being supplied excessively onto the workpiece.

[0118] FIG. 17 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to a sixth embodiment. The same components as those in FIG. 1 are assigned the same reference numerals, and their description will be omitted. Only the differences from FIG. 1 will be described. The additive manufacturing apparatus 100f according to the sixth embodiment further includes a strain gauge 31 that detects the force applied to the wire nozzle 122. When the wire W is in contact with the processing point, the wire W bends. When the wire W bends, the wire W comes into contact with the wire nozzle 122, and a force is applied to the wire nozzle 122. The strain gauge 31 measures the force applied to the wire nozzle 122. The strain gauge 31 outputs a strain measurement value, which is the measurement result, to the control device 21. The strain gauge 31 is an example of a load measurement unit that measures the load applied to the wire W.

[0119] When the strain measurement value from the strain gauge 31 is greater than a predetermined reference value, the control device 21 changes the feed speed of the wire W or changes the relative position between the wire W and the base material 51 so that the strain measurement value becomes equal to or less than the reference value. Specifically, the control device 21 reduces the feed speed of the wire W or moves the machining head 12 having the wire nozzle 122 in a direction away from the stage 11. In this example, the machining head 12 is moved because it is equipped with a movement mechanism in the Z-axis direction, but if the stage 11 is equipped with a movement mechanism in the Z-axis direction, the stage 11 may also be moved.

[0120] Fig. 18 is a flowchart showing an example of the procedure of the additive manufacturing method according to embodiment 6. Note that this flowchart shows the process of forming the first aluminum-containing metal layer 53 in step S15 of Fig. 3 or step S32 of Fig. 10, or the process of forming the second aluminum-containing metal layer 54 in step S16 of Fig. 3, step S34 of Fig. 10, or step S53 of Fig. 12.

[0121] First, the wire W is supplied onto the workpiece at a predetermined supply speed, and the laser beam L is irradiated onto the processing point (step S91). That is, the control device 21 controls the material supply unit so that the wire W is supplied to the processing point at the predetermined supply speed, and controls the irradiation unit so that the laser beam L is irradiated onto the processing point including the tip of the wire W. The predetermined supply speed is the wire W supply speed set in advance at the start of processing. Furthermore, when the wire W supply speed is reduced in step S94 described below, the predetermined supply speed is the wire W supply speed set in the most recent step S94.

[0122] Next, the control device 21 acquires a strain measurement value from the strain gauge 31 (step S92). The control device 21 determines whether the strain measurement value is higher than a predetermined reference value (step S93). If the strain measurement value is equal to or lower than the predetermined reference value (No in step S93), the wire W is not applying a force sufficient to damage the workpiece. Therefore, no special control is performed. The control device 21 determines whether the modeling process has been completed (step S96). If the modeling process has not been completed (No in step S96), the process returns to step S91. If the modeling process has been completed (Yes in step S96), the process ends.

[0123] On the other hand, if the measured distortion value is higher than the predetermined reference value (Yes in step S93), the supply speed of the wire W or the distance between the stage 11 and the machining head 12 is changed, and the laser beam L is irradiated onto the machining point (step S94). Specifically, the control device 21 controls the material supply unit so that the supply speed becomes slower than the current value, or controls the head driver 19 so that the machining head 12 moves in a direction away from the workpiece.

[0124] Thereafter, it is determined whether the formation process has been completed (step S95). If the formation process has not been completed (No in step S95), the process returns to step S92. If the formation process has been completed (Yes in step S95), the process ends.

[0125] In the above description, the control device 21 changes the feed speed of the wire W or the distance between the stage 11 and the machining head 12 when the measured distortion value of the wire W is greater than a predetermined reference value. When the measured distortion value of the wire W is greater than a predetermined reference value, it is considered that the tip of the wire W is in contact with the workpiece while the wire W is in a hard state, i.e., not melted. Therefore, it is also possible to perform control to soften the wire W. In one example, the control device 21 may increase the output of the laser beam L in addition to or instead of the above control. Furthermore, as shown in FIG. 13 , when a current can be passed through the wire W, the control device 21 may increase the current passed through the wire W in addition to or instead of the above control. Such control makes it possible to soften the wire W and reduce the load applied by the wire W to the workpiece.

[0126] Thus, in the sixth embodiment, the load that the wire W receives from the lamination surface of the base layer is measured during the process of laminating the first aluminum-containing metal layer 53 and the process of laminating the second aluminum-containing metal layer 54. If the load is greater than a predetermined reference value, the wire W feed speed or the relative position between the wire W and the base material 51 is changed. The additive manufacturing device 100f of FIG. 17 further includes a strain gauge 31 that measures the force applied to the wire nozzle 122, assuming that the load that the wire W receives from the lamination surface is equal to the force applied to the wire nozzle 122. This prevents the wire W in contact with the workpiece from applying excessive stress to the workpiece. As a result, it is possible to prevent scratches caused by the wire W scratching the workpiece and peeling of the base layer.

[0127] Seventh Embodiment If the output of the laser beam L is excessive, if the current flowing through the wire W is excessive, if the feed rate of the wire W is too low, or if the gap between the tip of the wire W and the layering surface is larger than expected, the wire W may break. When a break occurs, the molten metal turns into droplets and falls onto the workpiece. The droplets of molten metal that solidify on the workpiece have a distorted shape, different from the shape that would result if the wire W were melted and solidified on the workpiece. Furthermore, the impact of the molten metal droplets falling onto the workpiece may blow away the shielding gas G, potentially preventing the oxidation suppression effect. In this seventh embodiment, an additive manufacturing method is described in which the possibility of a break is detected and the output of the laser beam L, the feed rate of the wire W, or the current of the wire W is controlled based on the detection results.

[0128] Figure 19 is a diagram schematically showing an example of the configuration of an additive manufacturing apparatus according to embodiment 7. Note that the same components as those in Figures 1 and 13 are assigned the same reference numerals, and their description will be omitted. Only the parts that differ from Figures 1 and 13 will be described. The additive manufacturing apparatus 100g according to embodiment 7 differs from the additive manufacturing apparatus 100c according to embodiment 3 in that it has a mechanism for measuring the current flowing through the wire W or the voltage applied to the wire W. That is, in embodiment 7, the additive manufacturing apparatus 100g further includes a circuit tester 61 and a probe 62.

[0129] The circuit tester 61 measures the current flowing through the wire W or the voltage applied to the wire W. As described above, the current cables 27 are connected between the hot wire power supply 26 and the wire nozzle 122, and between the base material 51 and the hot wire power supply 26, respectively, and the tip of the wire W supplied from the wire nozzle 122 is in contact with the workpiece. Therefore, during the modeling process, a current flows through the wire W. The circuit tester 61 measures the current flowing through the wire W or the voltage applied to the wire W. The circuit tester 61 is connected to the control device 21 via wiring, and outputs the measurement results, that is, the measurement values, to the control device 21.

[0130] The probe 62 is electrically connected to the circuit tester 61 and is a probe used to measure the current flowing through or the voltage applied to the wire W. In this example, the probe 62 is electrically connected to the current cable 27 that connects the hot wire power supply 26 and the wire nozzle 122. The probe 62 may also be electrically connected to the current cable 27 that connects the hot wire power supply 26 and the base material 51.

[0131] When the wire W is in a normal state, the current flowing through the wire W or the voltage applied to the wire W exhibits a value determined according to the cross-sectional area, length, material, etc. of the wire W. However, when the wire W is about to melt, the molten wire W begins to separate from the workpiece, reducing the contact volume between the molten wire W and the workpiece, thereby increasing the resistivity. When the resistivity of the wire W increases, the current flowing through the wire W decreases and the voltage applied to the wire W increases. Furthermore, when the molten wire W completely separates from the workpiece, the resistance becomes infinite and no current flows. In other words, by referring to the measured value of the current or voltage of the wire W, it is possible to determine the possibility of melting. Therefore, in the seventh embodiment, the control device 21 determines the possibility of melting based on the measured value of the current or voltage of the wire W from the circuit tester 61, and when there is a possibility of melting, controls the output of the laser beam L, the feed speed of the wire W, or the current of the wire W.

[0132] When control is performed using the measured current value, the control device 21 determines whether the measured current value from the circuit tester 61 has decreased beyond the margin of error compared to a meltdown determination reference value, which is the current value when no meltdown has occurred. The meltdown determination reference value can be a statistical value, such as the average value of the wire W current when no meltdown has occurred, or a preset value set during the manufacturing process. If the measured current value matches the meltdown determination reference value, the control device 21 determines that no meltdown has occurred and continues the manufacturing process under the current processing conditions. If the measured current value has decreased compared to the meltdown determination reference value, the control device 21 determines that meltdown is imminent and controls the laser oscillator 13 to reduce the output of the laser beam L, controls the rotation motor 18 of the wire spool 17 to increase the feed speed of the wire W, or reduces the current used to heat the wire W. This prevents the wire W from melting. At this time, the control device 21 may change the amount of reduction in the output of the laser beam L, the amount of increase in the supply speed of the wire W, or the amount of reduction in the current for heating the wire W, depending on the magnitude of the difference between the melting determination reference value and the measured value of the current. Furthermore, when the measured value of the current becomes 0, this indicates that melting has occurred in the wire W, and the control device 21 stops the modeling process.

[0133] When control is performed using the voltage measurement value, the control device 21 compares the voltage measurement value from the circuit tester 61 with a meltdown determination reference value, which is the voltage value when no meltdown has occurred, and determines whether the measured voltage value from the circuit tester 61 has risen beyond the error range. The meltdown determination reference value can be a statistical value, such as the average value of the voltage values ​​obtained in advance when no meltdown has occurred. If the measured voltage value matches the meltdown determination reference value, the control device 21 determines that meltdown has not occurred and continues the manufacturing process under the current processing conditions. If the measured voltage value rises compared to the meltdown determination reference value, the control device 21 determines that meltdown is imminent and controls the laser oscillator 13 to reduce the output of the laser beam L, controls the rotary motor 18 of the wire spool 17 to increase the feed speed of the wire W, or reduces the current of the wire W. This prevents meltdown of the wire W. At this time, the control device 21 may change the amount of reduction in the output of the laser beam L, the amount of increase in the supply speed of the wire W, or the amount of reduction in the current heating the wire W, depending on the magnitude of the difference between the melting judgment reference value and the measured voltage value.

[0134] 20 is a flowchart showing an example of the procedure of the additive manufacturing method according to embodiment 7. Note that this example shows a case where the output of the laser beam L is controlled using the current flowing through the wire W when the first aluminum-containing metal layer 53 or the second aluminum-containing metal layer 54 is formed.

[0135] First, the wire W is supplied onto the workpiece at a predetermined feed rate, and a laser beam L of a predetermined output power is irradiated (step S111). That is, the control device 21 controls the material supply unit so that the wire W is supplied to the processing point at the predetermined feed rate, and controls the irradiation unit so that the laser beam L of a predetermined output power is irradiated to the processing point. The predetermined feed rate is the wire W feed rate set in advance at the start of processing. Furthermore, if the feed rate is reduced in step S114 described later, the predetermined feed rate is the wire W feed rate set in the most recent step S114. The predetermined output power is the laser beam L output set in advance at the start of processing. Furthermore, if the output power of the laser beam L is reduced in step S114 described later, the predetermined output power is the laser beam L output set in the most recent step S114.

[0136] The circuit tester 61 measures the current flowing through the wire W during the modeling process. The control device 21 acquires the measured value of the current of the wire W from the circuit tester 61 (step S112). The control device 21 determines whether the measured value of the current is lower than the melting determination reference value (step S113).

[0137] If the measured current value is lower than the melting determination reference value (Yes in step S113), the control device 21 determines whether the measured current value is 0 (step S114). If the measured current value is not 0 (No in step S114), the control device 21 irradiates the laser beam L, supplies the wire W, and heats the wire W under conditions of reducing the output of the laser beam L, increasing the supply speed of the wire W, or reducing the current of the wire W (step S115). Thereafter, the control device 21 determines whether the modeling process has been completed (step S116). If the modeling process has not been completed (No in step S116), the process returns to step S112. If the modeling process has been completed (Yes in step S116), the process ends. If the measured current value is 0 in step S114 (Yes in step S114), the process ends.

[0138] On the other hand, if the measured current value is equal to or greater than the melting determination reference value (No in step S113), the control device 21 determines whether the modeling process has ended (step S117). If the measured current value is equal to or greater than the melting determination reference value, the wire W has not been melted by the irradiation of the laser beam L. Therefore, the current feed speed of the wire W, the output of the laser beam L, and, if the wire W is heated, the current of the wire W are maintained, and no special control is performed. Therefore, if the modeling process has not ended (No in step S117), the process returns to step S111. If the modeling process has ended (Yes in step S117), the process ends.

[0139] 20 shows an example in which the measurement value of the current of the wire W is used to determine whether or not a blowout has occurred. However, the measurement value of the voltage may also be used to determine whether or not a blowout has occurred. In this case, in step S113, if the measurement value of the voltage is higher than the blowout determination reference value, the process proceeds to step S115. If the measurement value of the voltage is equal to or lower than the blowout determination reference value, the process proceeds to step S117.

[0140] In the seventh embodiment, the additive manufacturing apparatus 100g further includes a circuit tester 61 that measures the current flowing through the wire W or the voltage applied to the wire W. When the measured value of the current of the wire W measured by the circuit tester 61 is lower than the melting determination reference value, or when the measured value of the voltage of the wire W is higher than the melting determination reference value, the control device 21 outputs the laser beam L, supplies the wire W, and heats the wire W under conditions that reduce the output of the laser beam L, increase the feed speed of the wire W, or reduce the current of the wire W. This makes it possible to prevent the wire W from melting.

[0141] Eighth Embodiment In the eighth embodiment, an additive manufacturing method will be described in which the position of the tip of the wire W is detected during the manufacturing process, and the feed speed of the wire W is controlled based on the detected position of the tip of the wire W and the height of the workpiece.

[0142] FIG. 21 is a schematic diagram illustrating an example of the configuration of an additive manufacturing apparatus according to embodiment 8. Components identical to those in FIGS. 1, 11, 13, and 17 are denoted by the same reference numerals, and their description will be omitted. Differences from FIGS. 1, 11, 13, and 17 will be described. The additive manufacturing apparatus 100h according to embodiment 8 further includes, in addition to the configuration illustrated in FIG. 13, a strain gauge 31 and an imaging unit 63 that captures an image of the processing point, which is the position of irradiation of the laser beam L on the workpiece. An example of the imaging unit 63 is a camera that captures an image of an area including the processing point. The imaging unit 63 may be mounted inside or outside the processing head 12. If mounted inside the processing head 12, it is desirable to mount the imaging unit 63 so that it is aligned with the axis of the output of the laser beam L. This allows imaging from directly above the processing point, thereby enabling more accurate acquisition of the position of the wire W. The imaging unit 63 outputs image data representing the image of the area including the processing point to the control device 21.

[0143] The control device 21 adjusts at least one of the feed speed of the wire W, the current flowing through the wire W, and the output of the laser beam L in accordance with the position of the tip of the wire W and the position of the processing point obtained from image data capturing an image of an area including the processing point, which is the irradiation position of the laser beam L, and the strain measurement value acquired from the strain gauge 31. Specifically, the control device 21 performs image analysis of the image data from the imaging unit 63 to extract the position of the tip of the wire W and the processing point. The control device 21 determines, based on the processing point as a reference, whether the position of the tip of the wire W is at the processing point, has passed the processing point, or is closer to the wire nozzle 122 than the processing point. The control device 21 also compares the strain measurement value with a predetermined reference value. The control device 21 then adjusts at least one of the feed speed of the wire W, the current flowing through the wire W, and the output of the laser beam L in accordance with the position of the tip of the wire W relative to the processing point and the magnitude of the strain measurement value relative to the reference value. In this example, the force applied to the wire nozzle 122 is detected by the strain gauge 31, but any device capable of measuring the load on the wire W is not limited to the strain gauge 31. In other words, the control device 21 is required only to measure the load that the wire W receives from the base layer, and to adjust the feed speed of the wire W and the current flowing through the wire W in accordance with the position of the tip of the wire W relative to the processing point and the magnitude of the load relative to a predetermined reference value.

[0144] When the position of the tip of the wire W is at the processing point and the strain measurement value is the reference value, the current feed speed of the wire W and the current flowing through the wire W are appropriate, so the control device 21 maintains this state. Note that the reference value may have a range.

[0145] When the position of the tip of the wire W is closer to the wire nozzle 122 than the processing point and the measured strain value is higher than the reference value, it is considered that the wire W is not about to melt, but rather that the height of the workpiece is higher than expected, i.e., the aluminum-containing metal layer is stacked higher than expected, and the tip of the wire W is located on the wire nozzle 122 side. In other words, the tip of the wire W is stuck in the workpiece near the processing point, which is higher than expected. In such a case, the control device 21 reduces the feed speed of the wire W or increases the current flowing through the wire W.

[0146] When the position of the tip of the wire W is closer to the wire nozzle 122 than the processing point and the measured strain value is lower than the reference value, it can be determined that the wire W is about to melt. Therefore, the control device 21 increases the feed speed of the wire W, reduces the current flowing through the wire W, or reduces the output of the laser beam L.

[0147] If the position of the tip of the wire W has passed the processing point and the measured strain value is higher than the reference value, it can be determined that the current supply speed of the wire W is too fast and the wire W has penetrated further than the processing point. Therefore, the control device 21 reduces the supply speed of the wire W or increases the current flowing through the wire W.

[0148] If the position of the tip of the wire W has passed the processing point and the strain measurement value is lower than the reference value, the height of the workpiece near the processing point is lower than expected, that is, the aluminum-containing metal layer is layered lower than expected, and the position of the tip of the wire W is inserted further back than the processing point, but not deep enough to penetrate the workpiece. In such a case, since the wire W has not penetrated the workpiece, the control device 21 reduces the feed speed of the wire W, but does nothing about the current flowing through the wire W, because reducing the current may cause it to melt.

[0149] 22 and 23 are flowcharts showing an example of the procedure of the additive manufacturing method according to embodiment 8. Note that these flowcharts show the process of controlling the feed speed of the wire W and the current flowing through the wire W when forming the first aluminum-containing metal layer 53 or the second aluminum-containing metal layer 54.

[0150] First, the wire W is supplied onto the workpiece at a predetermined feed rate, a predetermined current is passed through the wire W, and the laser beam L is irradiated onto the processing point (step S131). That is, the control device 21 controls the material supply unit so that the wire W is supplied to the processing point at the predetermined feed rate, controls the hot wire power supply 26 so that a predetermined current flows through the wire W, and controls the irradiation unit so that the laser beam L is irradiated onto the processing point. The predetermined feed rate is the wire W feed rate set in advance at the start of processing. Furthermore, if the wire W feed rate is changed in step S137, step S139, step S141, step S145, or step S146 (described later), the predetermined feed rate is the wire W feed rate set in the most recent step S137, step S139, step S141, step S145, or step S146. The predetermined current is the current to be passed through the wire W set in advance at the start of processing. Furthermore, if the current flowing through the wire W is changed in step S137, step S139, or step S145 described below, the determined current is the current flowing through the wire W determined in the most recent step S137, step S139, or step S145.

[0151] Next, the control device 21 acquires image data of an area including the processing point from the imaging unit 63 (step S132). The control device 21 performs image analysis of the image data and acquires the positions of the processing point and the tip of the wire W from the image data (step S133). The control device 21 also acquires strain measurement values ​​from the strain gauges 31 (step S134).

[0152] Thereafter, the control device 21 determines whether the position of the tip of the wire W is closer to the wire nozzle 122 than the processing point (step S135). If the position of the tip of the wire W is closer to the wire nozzle 122 than the processing point (if Yes in step S135), the control device 21 determines whether the measured distortion value is higher than a predetermined reference value (step S136). If the measured distortion value is higher than the predetermined reference value (if Yes in step S136), the control device 21 reduces the feed speed of the wire W from the current feed speed, increases the current flowing through the wire W, or increases the output of the laser beam L (step S137).

[0153] If the measured distortion value is not higher than the predetermined reference value (No in step S136), the control device 21 determines whether the measured distortion value is lower than the predetermined reference value (step S138). If the measured distortion value is lower than the predetermined reference value (Yes in step S138), the control device 21 increases the feed speed of the wire W from the current feed speed, reduces the current flowing through the wire W, or reduces the output of the laser beam L (step S139). This is because the wire W is about to melt.

[0154] After that, or after step S137, the control device 21 determines whether the formation process has been completed (step S140). If the formation process has not been completed (No in step S140), the process returns to step S132. On the other hand, if the formation process has been completed (Yes in step S140), the process ends.

[0155] If the distortion measurement value in step S138 is not lower than the predetermined reference value (No in step S138), the tip position of the wire W is on the wire nozzle 122 side, but the distortion measurement value is within an appropriate range. In this case, the control device 21 increases the supply speed of the wire W (step S141). Thereafter, the control device 21 determines whether the modeling process has been completed (step S142). If the modeling process has not been completed (No in step S142), the process returns to step S131. On the other hand, if the modeling process has been completed (Yes in step S142), the process ends.

[0156] In step S135, if the position of the tip of the wire W is not on the wire nozzle 122 side of the processing point (if No in step S135), the control device 21 determines whether the position of the tip of the wire W has passed the processing point (step S143). If the position of the tip of the wire W has passed the processing point (if Yes in step S143), the control device 21 determines whether the measured strain value is higher than a predetermined reference value (step S144). If the measured strain value is higher than the predetermined reference value (if Yes in step S144), the control device 21 reduces the supply speed of the wire W from the current supply speed or increases the current flowing through the wire W (step S145).

[0157] If the measured strain value is not higher than the predetermined reference value (No in step S144), the control device 21 reduces the supply speed of the wire W from the current supply speed (step S146). Thereafter, the process proceeds to step S140.

[0158] If the position of the tip of the wire W has not passed the processing point in step S143 (No in step S143), the position of the tip of the wire W is at the processing point. In this case, the feed speed of the wire W and the current flowing through the wire W are appropriate, so no special control is performed and the current feed speed is maintained. Then, the process proceeds to step S142.

[0159] The eighth embodiment includes a strain gauge 31 that measures the load on the wire W, and an imaging unit 63 that can image the position of the wire W during the modeling process. The control device 21 acquires the processing point and the position of the tip of the wire W from the image data captured by the imaging unit 63. The control device 21 then adjusts the feed speed of the wire W, the current flowing through the wire W, or the output of the laser beam L based on a combination of the position of the tip of the wire W and the load on the wire W. This makes it possible to prevent the wire W from melting or being plunged too far.

[0160] In the above description, the state of insertion of the wire W into the workpiece is detected by the strain gauge 31, but other methods may be used for detection. In one example, the additive manufacturing device 100h may further include an imaging unit that monitors the processing point from an oblique angle, instead of the strain gauge 31. This imaging unit is different from the imaging unit 63. In this case, the state of insertion of the wire W, including the height of the workpiece, can be obtained from the image captured by the imaging unit.

[0161] Ninth Embodiment In the ninth embodiment, a description will be given of an additive manufacturing method in which the temperature of the tip of the wire W is measured during the manufacturing process, and the output of the laser beam L or the supply speed of the wire W is controlled based on the measured temperature of the tip of the wire W.

[0162] FIG. 24 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to a ninth embodiment. The same components as those in FIGS. 1, 11, 13, and 15 are denoted by the same reference numerals, and their description will be omitted. The differences from FIGS. 1, 11, 13, and 15 will be described. The additive manufacturing apparatus 100i according to the ninth embodiment further includes a temperature measurement unit 30 that measures the temperature of the processing point, which is the position where the laser beam L is irradiated on the workpiece, in addition to the configuration of FIG. 13 . The temperature measurement unit 30 measures the temperature of the processing point, which is the position where the laser beam L is irradiated. However, in the ninth embodiment, the temperature measurement unit 30 measures the temperature of the tip of the wire W. However, because the tip of the wire W is supplied aiming at the center of the irradiation position of the laser beam L, the temperature of the tip of the wire W can be considered to be the same as the temperature of the processing point. In other words, in the ninth embodiment, the temperature of the processing point is considered to be the temperature of the tip of the wire W.

[0163] Furthermore, the control device 21 adjusts at least one of the output of the laser beam L, the feed speed of the wire W, and the current flowing through the wire W, based on a temperature measurement value that is a measurement value of the temperature of the tip of the wire W obtained from the temperature measurement unit 30. Specifically, when the temperature of the tip of the wire W measured by the temperature measurement unit 30 is higher than a predetermined reference value, the control device 21 performs at least one of a process of reducing the output of the laser beam L, a process of increasing the feed speed of the wire W, and a process of reducing the current through the wire W.

[0164] FIG. 25 is a flowchart showing an example of the steps of the additive manufacturing method according to the ninth embodiment. First, the wire W is supplied onto the workpiece at a predetermined supply speed, and the laser beam L having a predetermined output power is irradiated onto the processing point (step S151). That is, the control device 21 controls the material supply unit so that the wire W is supplied to the processing point at the predetermined supply speed, and controls the irradiation unit so that the laser beam L is irradiated onto the processing point at the predetermined output power. The predetermined supply speed is the wire W supply speed set in advance at the start of processing. Furthermore, if the wire W supply speed is changed in step S154 (described later), the predetermined supply speed is the wire W supply speed set in the immediately preceding step S154. The predetermined output power is the laser beam L output set in advance at the start of processing. Furthermore, if the laser beam L output power is changed in step S154 (described later), the predetermined output power is the laser beam L output power set in the immediately preceding step S154.

[0165] The temperature measurement unit 30 constantly measures the temperature of the tip of the wire W during the modeling process. The control device 21 acquires a temperature measurement value, which is a measurement value of the temperature of the tip of the wire W, from the temperature measurement unit 30 (step S152). The control device 21 determines whether the temperature measurement value is higher than a predetermined melting determination reference value (step S153). If the temperature measurement value is equal to or lower than the melting determination reference value (No in step S153), the workpiece is in a state where heat has not yet been accumulated by irradiation with the laser beam L. Therefore, no special control is performed, and the current feed rate of the wire W and the output of the laser beam L are maintained. The control device 21 determines whether the modeling process has been completed (step S156). If the modeling process has not been completed (No in step S156), the process returns to step S151. If the modeling process has been completed (Yes in step S156), the process ends.

[0166] On the other hand, if the measured temperature is higher than the melting determination reference value (Yes in step S153), the control device 21 performs at least one of the following processes: reducing the output of the laser beam L, increasing the feed rate of the wire W, and reducing the current of the wire W, thereby supplying the wire W, heating the wire W, and irradiating the laser beam L (step S154). That is, the control device 21 controls the irradiation unit to output a laser beam L with a lower output than the current output of the laser beam L. Alternatively, the control device 21 controls the rotary motor 18 of the wire spool 17 to increase the feed rate of the wire W higher than the current feed rate. Alternatively, the control device 21 controls the hot-wire power supply 26 to decrease the current flowing through the wire W lower than the current current. By performing such control, melting of the wire W can be suppressed.

[0167] Thereafter, it is determined whether the formation process has been completed (step S155). If the formation process has not been completed (No in step S155), the process returns to step S152. On the other hand, if the formation process has been completed (Yes in step S155), the process ends.

[0168] In the ninth embodiment, the additive manufacturing apparatus 100i further includes a temperature measurement unit 30 that measures the temperature of the tip of the wire W. When the temperature measurement value of the tip of the wire W measured by the temperature measurement unit 30 is higher than the melting determination reference value, the control device 21 irradiates the laser beam L while performing at least one of a process of reducing the output of the laser beam L, a process of increasing the feed speed of the wire W, and a process of reducing the current flowing through the wire W. This makes it possible to prevent melting of the wire W due to continuous irradiation of the laser beam L.

[0169] Tenth Embodiment In a tenth embodiment, a case will be described in which machine learning is performed using a plurality of sensing results by a detection unit during a modeling process and modeling results, and whether a state in which blowout is likely to occur is determined from the sensing results.

[0170] Fig. 26 is a diagram schematically illustrating an example of the configuration of an additive manufacturing apparatus according to embodiment 10. Note that the same components as those described in embodiments 1 to 9 are assigned the same reference numerals, and their description will be omitted. As shown in Fig. 26, the additive manufacturing apparatus 100j according to embodiment 10 includes a hot wire power supply 26, a current cable 27, a temperature measurement unit 30, a strain gauge 31, a circuit tester 61, a probe 62, and an imaging unit 63. The additive manufacturing apparatus 100j also includes a learning device 300 and an inference device 350.

[0171] 27 is a block diagram showing an example of the configuration of a learning device in the additive manufacturing apparatus according to embodiment 10. The learning device 300 includes a data acquisition unit 301, a model generation unit 302, and a trained model storage unit 303.

[0172] The data acquisition unit 301 acquires sensing data and modeling result data as learning data.

[0173] The sensing data includes at least one of the temperature of the tip of the wire W during the modeling process and the temperature of the tip of the wire W before the modeling process obtained from the temperature measurement unit 30, the current flowing through the wire W or the voltage applied to the wire W obtained from the circuit tester 61, the position of the tip of the wire W extracted from image data obtained from the imaging unit 63, and the load applied to the wire W obtained from the load measurement unit. The temperature of the tip of the wire W during the modeling process and the temperature of the tip of the wire W before the modeling process are data obtained from the temperature measurement unit 30. The current flowing through the wire W or the voltage applied to the wire W are data obtained from the circuit tester 61. The position of the tip of the wire W is data obtained from the imaging unit 63. An example of the load applied to the wire W obtained from the load measurement unit is the force applied to the wire nozzle 122 obtained from the strain gauge 31. The force applied to the wire nozzle 122 is data obtained from the strain gauge 31. The data acquisition unit 301 may acquire each of these pieces of data from the temperature measurement unit 30, the circuit tester 61, the imaging unit 63, and the strain gauge 31, or from the control device 21 that stores the above data. The sensing data may include at least one of the temperature of the tip of the wire W during the modeling process, the temperature of the tip of the wire W before the modeling process, the current flowing through the wire W or the voltage applied to the wire W, the position of the tip of the wire W, and the force applied to the wire nozzle 122.

[0174] The modeling result data is data indicating the results of a modeling process performed by the additive manufacturing apparatus 100j using the conditions obtained from the sensing data. The modeling result data is stored in association with the sensing data. In one example, the modeling result data is stored in the control device 21. In this example, the modeling result data includes processing point positional relationship information and bead shape data including the width and height of the bead shape. Of this modeling result data, data that associates the processing point positional relationship information, which is the modeling result when the load caused by the plunge of the wire W into the workpiece is small, with the bead shape data of a bead having the targeted width and height, is used as the correct answer data. In other words, the learning data is the sensing data and modeling result data when the modeling result when the load is small and a bead having the targeted shape are obtained.

[0175] 28 is a diagram showing an example of processing point positional relationship information. The processing point positional relationship information is information that indicates the relationship between the position of the tip of the wire W at the processing point when the sensing data is acquired and the irradiation position of the laser beam L. The processing point positional relationship information includes drop, smooth, and stub.

[0176] The smooth state is a state in which the melting position of the wire W is at approximately the same position as the top surface of the bead formed up to that point. That is, in the smooth state, the shaping process is performed in an optimal state in which the tip of the wire W is positioned at the processing point, which is the irradiation position of the laser beam L. When the shaping process is performed in this state, the bead has a uniform width and height, as shown in the schematic diagram of the bead shape in Figure 28. Therefore, the surface is also smooth.

[0177] In the case of a drop, the melting position of the wire W is higher than the upper surface of the bead formed in a smooth state. That is, in the case of a drop, the tip of the wire W is located closer to the wire nozzle 122 than the processing point, and the manufacturing process is performed in this state. When the manufacturing process is performed in this state, the wire W melts above the upper surface of the bead, forming droplets. These droplets then solidify. Furthermore, the droplets burst upward, generating spatter. As a result, as shown in the bead shape in Figure 28, the bead becomes wider and higher than in the case of a smooth state. Furthermore, because droplets of non-uniform size fall, the width and height of the bead are not uniform. Furthermore, if the droplets take a long time to fall, nothing is welded. In other words, when melting occurs, the bead is completely torn off, and the droplets burst, forming round lumps scattered around.

[0178] In the case of a stub, the melting position of the wire W is lower than the position of the top surface of the bead formed in a smooth state. In other words, in the case of a stub, the forming process is performed in a state where the tip of the wire W has passed the processing point. When the forming process is performed in this state, the wire W melts and solidifies below the position of the top surface of the bead. As a result, as shown in the bead shape in Figure 28, the bead width is narrower and the bead height is lower than in the case of a smooth bead. Furthermore, because the melting of the wire W is uneven, the width and height of the bead are not uniform and have irregularities. As a result, the surface of the bead is not smooth, as in the case of a drop.

[0179] During the modeling process, the control device 21 acquires processing point positional relationship information that indicates the relationship between the position of the tip of the wire W and the irradiation position of the laser beam L, and after the modeling process, acquires bead shape data including the width and height of the bead. In one example, the processing point positional relationship information and the bead shape data are input to the control device 21 by a user of the additive manufacturing device 100j. The processing point positional relationship information and the bead shape data are associated with each other to form modeling result data. The data acquisition unit 301 acquires the modeling result data from the control device 21.

[0180] Returning to FIG. 27 , the model generation unit 302 uses the training data to generate a trained model for inferring modeling result prediction information, which is a predicted result of the modeling process in the additive manufacturing device 100j, from the sensing data of the additive manufacturing device 100j. In other words, the model generation unit 302 learns the modeling result prediction information using the training data created based on a combination of the sensing data and the modeling result data output from the data acquisition unit 301. That is, the model generation unit 302 generates a trained model for inferring optimal modeling result prediction information from the sensing data and the modeling result data of the additive manufacturing device 100j. Here, the training data is data in which the sensing data and the modeling result data are associated with each other. The modeling result prediction information includes a predicted value of the modeling result predicted when the sensing data is used as input data, and a predicted value of the bead shape, including the width and height. The predicted value of the modeling result indicates processing point positional relationship information, specifically, one of drop, stub, and smooth. The model generation unit 302 uses, as learning data, a combination of the sensing data and the correct answer data when the modeling result when the load is small and the bead having the targeted shape is obtained. Here, the correct answer data is data that associates processing point positional relationship information, which is the modeling result when the load due to the plunge of the wire W into the workpiece is small, with bead shape data of the bead having the targeted width and height.

[0181] The learning algorithm used by the model generation unit 302 may be a known algorithm such as supervised learning, unsupervised learning, reinforcement learning, etc. As an example, a case where a neural network is applied will be described.

[0182] In one example, the model generation unit 302 learns the modeling result prediction information by so-called supervised learning in accordance with a neural network model. Here, supervised learning refers to a method in which a set of data, each of which is an input and a label representing a result, is provided to the learning device 300, and the learning device 300 learns the features of the learning data and infers the result from the input.

[0183] A neural network consists of an input layer consisting of multiple neurons, an intermediate layer consisting of multiple neurons, and an output layer consisting of multiple neurons. The intermediate layer, also called a hidden layer, may be one layer or two or more layers.

[0184] FIG. 29 is a diagram schematically illustrating an example of a neural network used by the model generation unit of FIG. 27 . In one example, in a three-layer neural network such as that shown in FIG. 29 , when multiple inputs are input to input layer X1 through input layer X3, these values ​​are multiplied by weights indicated by w11 through w16 and then input to intermediate layer Y1 through intermediate layer Y2. When weights w11 through w16 are not individually distinguished, they are referred to as weight w1. Furthermore, the results from intermediate layer Y1 through intermediate layer Y2 are further multiplied by weights indicated by w21 through w26 and output from output layer Z1 through output layer Z3. When weights w21 through w26 are not individually distinguished, they are referred to as weight w2. The output results from output layer Z1 through output layer Z3 vary depending on the values ​​of weights w1 and w2.

[0185] In the tenth embodiment, the neural network learns the modeling result prediction information by so-called supervised learning in accordance with the learning data created based on a combination of the sensing data and the modeling result data acquired by the data acquisition unit 301.

[0186] That is, the neural network learns by inputting sensing data to the input layer and adjusting the weights W1 and W2 so that the result output from the output layer approaches the modeling result data, which is the correct data.

[0187] The model generation unit 302 generates and outputs a trained model by performing the above-described learning.

[0188] Returning to FIG. 27 , the trained model storage unit 303 stores the trained model output from the model generation unit 302.

[0189] Next, the learning process performed by the learning device 300 will be described with reference to Fig. 30. Fig. 30 is a flowchart showing an example of the procedure of the learning process performed by the learning device of the additive manufacturing apparatus according to the tenth embodiment.

[0190] The data acquiring unit 301 acquires sensing data and modeling result data when a modeling result under a small load and a bead having a desired shape are obtained (step S171). Note that although the sensing data and the modeling result data are acquired simultaneously, it is sufficient that the sensing data and the modeling result data are input in association with each other, and the sensing data and the modeling result data may be acquired at different times.

[0191] Next, the model generation unit 302 learns the printing result prediction information by so-called supervised learning according to the learning data created based on a combination of the sensing data and printing result data acquired by the data acquisition unit 301, and generates a trained model using an estimation algorithm that shows the correlation between the temperature of the tip of the wire W during the printing process, the temperature of the tip of the wire W before the printing process, the current flowing through the wire W or the voltage applied to the wire W, the position of the tip of the wire W, and the force applied to the wire nozzle 122, and the processing point position relationship information and bead shape data (step S172).

[0192] Then, the trained model storage unit 303 stores the trained model generated by the model generation unit 302 (step S173). This ends the processing.

[0193] 31 is a diagram schematically illustrating an example of the configuration of an inference device in the additive manufacturing apparatus according to embodiment 10. The inference device 350 is a device that inputs sensing data to a trained model and outputs the result obtained as modeling result prediction information. The inference device 350 includes a data acquisition unit 351 and an inference unit 352.

[0194] The data acquisition unit 351 acquires sensing data. The sensing data includes at least one of the temperature of the tip of the wire W during the modeling process and the temperature of the tip of the wire W before the modeling process acquired from the temperature measurement unit 30, the current flowing through the wire W or the voltage applied to the wire W acquired from the circuit tester 61, the position of the tip of the wire W extracted from image data acquired from the imaging unit 63, and the load applied to the wire W acquired from the load measurement unit. The temperature of the tip of the wire W during the modeling process and the temperature of the tip of the wire W before the modeling process are data acquired from the temperature measurement unit 30. The current flowing through the wire W or the voltage applied to the wire W are data acquired from the circuit tester 61. The position of the tip of the wire W is data acquired from the imaging unit 63. An example of the load applied to the wire W acquired from the load measurement unit is the force applied to the wire nozzle 122 acquired from the strain gauge 31. The force applied to the wire nozzle 122 is data acquired from the strain gauge 31. The data acquisition unit 351 may acquire each of these pieces of data from the temperature measurement unit 30, the circuit tester 61, the imaging unit 63, and the strain gauge 31, or may acquire the data from the control device 21 that stores the above data. The sensing data may include at least one of the temperature of the tip of the wire W during the modeling process, the temperature of the tip of the wire W before the modeling process, the current flowing through the wire W or the voltage applied to the wire W, the position of the tip of the wire W, and the force applied to the wire nozzle 122.

[0195] The inference unit 352 infers modeling result prediction information obtained by using the trained model. That is, by inputting the sensing data acquired by the data acquisition unit 351 to this trained model, it is possible to output modeling result prediction information inferred from the sensing data.

[0196] In the tenth embodiment, a case has been described in which a trained model trained from the sensing data and the modeling result data of the additive manufacturing device 100j is used. However, a trained model trained from the sensing data and the modeling result data of another additive manufacturing device 100j or the like may be externally acquired, and modeling result prediction information may be output based on this trained model.

[0197] Next, a process for obtaining modeling result prediction information using the inference device 350 will be described with reference to Fig. 32. Fig. 32 is a flowchart showing an example of the procedure of an estimation process performed by the inference device of the layered modeling apparatus according to the tenth embodiment.

[0198] First, the data acquiring unit 351 acquires sensing data (step S191). The sensing data includes the temperature of the tip of the wire W during the modeling process, the temperature of the tip of the wire W before the modeling process, the current flowing through the wire W or the voltage applied to the wire W, the position of the tip of the wire W, and the force applied to the wire nozzle 122.

[0199] Next, the inference unit 352 inputs the sensing data into the learned model stored in the learned model storage unit 303, and obtains modeling result prediction information (step S192).

[0200] Thereafter, the inference unit 352 outputs the modeling result prediction information obtained by the learned model to the additive manufacturing apparatus 100j, specifically to the control device 21 of the additive manufacturing apparatus 100j (step S193).

[0201] Then, the control device 21 uses the outputted printing result prediction information to control at least one of the output of the laser beam L, the supply speed of the wire W, and the current passed through the wire W (step S194). When the predicted value of the printing result of the printing result prediction information is smooth, for example, the control device 21 maintains the current state. Alternatively, when the predicted value of the bead shape of the printing result prediction information differs from the reference value of a desired bead shape, the control device 21 adjusts at least one of the output of the laser beam L, the supply speed of the wire W, and the current passed through the wire W so that the bead shape approaches the reference value.

[0202] When the predicted value of the forming result in the forming result prediction information is a drop, there is a possibility that melting has occurred. Therefore, the control device 21 adjusts at least one of the output of the laser beam L, the feed speed of the wire W, and the current flowing through the wire W so that the predicted value of the bead shape approaches the reference value.

[0203] If the predicted value of the forming result in the forming result prediction information is a stub, there is a possibility that the wire W is applying stress to the workpiece. Therefore, the control device 21 adjusts at least one of the output of the laser beam L, the feed speed of the wire W, and the current flowing through the wire W so that the predicted value of the bead shape approaches the reference value.

[0204] Here, an example of the control of the control device 21 when the predicted value of the modeling result is a drop or a stub will be described. When the current flowing through the wire W is lower or more variable than expected, it can be determined that there is a possibility of melting. In such a case, i.e., when the predicted value of the modeling result is a drop, the wire W is on the verge of melting, so the control device 21 may perform at least one of the following processes: reducing the output of the laser beam L, increasing the feed speed of the wire W, and reducing the current flowing through the wire W.

[0205] When the voltage applied to the wire W is higher or more variable than expected, it can be determined that there is a possibility of melting. In such a case, that is, when the predicted value of the forming result is a drop, in order to prevent melting, the control device 21 may perform at least one of the following processes: reducing the output of the laser beam L, increasing the feed speed of the wire W, and reducing the current flowing through the wire W.

[0206] When the position of the tip of the wire W is closer to the wire nozzle 122 than the processing point, it can be determined that the wire W is about to melt. In this case, that is, when the predicted value of the molding result is a drop, the control device 21 may perform at least one of the following processes: reducing the output of the laser beam L, increasing the supply speed of the wire W, and reducing the current flowing through the wire W.

[0207] If the position of the tip of the wire W passes the processing point, it can be determined that the melting of the wire W is insufficient. In this case, that is, if the predicted value of the molding result is a stub, the control device 21 may perform at least one of the following processes: increasing the output of the laser beam L, decreasing the feed speed of the wire W, and increasing the current flowing through the wire W.

[0208] If the temperature of the tip of the wire W is higher than expected, it can be determined that there is a possibility of melting. In such a case, that is, if the predicted value of the manufacturing result is a drop, the control device 21 may perform at least one of the following processes to lower the temperature of the tip of the wire W: reducing the output of the laser beam L, increasing the feed speed of the wire W, and reducing the current flowing through the wire W.

[0209] If the load on the wire W is higher than expected, it can be determined that the wire W is not sufficiently melted. In such a case, i.e., if the predicted value of the manufacturing result is a stub, the control device 21 can perform at least one of the following processes to increase the temperature of the tip of the wire W: increasing the output of the laser beam L, decreasing the feed speed of the wire W, and increasing the current flowing through the wire W. This can suppress the occurrence of melting of the wire W or the stress that the wire W imparts to the workpiece. This completes the process.

[0210] In the tenth embodiment, a case where supervised learning is applied to the learning algorithm used by the model generation unit 302 has been described, but the present invention is not limited to this. As for the learning algorithm, reinforcement learning, unsupervised learning, semi-supervised learning, etc. can also be applied in addition to supervised learning.

[0211] The model generation unit 302 may also learn the modeling result prediction information according to training data created for multiple additive manufacturing devices 100j. The model generation unit 302 may acquire training data from multiple additive manufacturing devices 100j used in the same area, or may learn the modeling result prediction information using training data collected from multiple additive manufacturing devices 100j operating independently in different areas. It is also possible to add or remove additive manufacturing devices 100j that collect training data from the target during the process. Furthermore, the learning device 300 that learned the modeling result prediction information for a certain additive manufacturing device 100j may be applied to another additive manufacturing device 100j, and the modeling result prediction information for the other additive manufacturing device 100j may be re-learned and updated.

[0212] Furthermore, the learning algorithm used in the model generation unit 302 may be deep learning, which learns to extract the features themselves, or machine learning may be performed according to other known methods, such as genetic programming, functional logic programming, or support vector machines.

[0213] Furthermore, the learning device 300 and the inference device 350 are used to learn the modeling result prediction information of the additive manufacturing device 100j. In one example, the learning device 300 and the inference device 350 may be connected to the additive manufacturing device 100j via a network and may be separate devices from the additive manufacturing device 100j. Alternatively, the learning device 300 and the inference device 350 may be built into the control device 21 of the additive manufacturing device 100j. Alternatively, the learning device 300 and the inference device 350 may exist on a cloud server.

[0214] Next, hardware for realizing the learning device 300 and the inference device 350 according to the tenth embodiment will be described. Fig. 33 is a block diagram showing an example of a hardware configuration for realizing the learning device and the inference device in the additive manufacturing apparatus according to the tenth embodiment. Fig. 33 shows a configuration in which the learning device 300 and the inference device 350 are realized by a processing circuit 571 having a processor 573 and a memory 574.

[0215] The input unit 572 is a circuit that receives input signals for the learning device 300 and the inference device 350 from the outside. The output unit 575 is a circuit that outputs signals generated by the learning device 300 and the inference device 350 to the outside. The data acquisition unit 301 of the learning device 300 and the data acquisition unit 351 of the inference device 350 are realized by the input unit 572. The input unit 572 is also responsible for inputting the trained model. The output unit 575 is responsible for outputting the trained model in the learning device 300, and is responsible for outputting modeling result prediction information in the inference device 350.

[0216] Processor 573 is a CPU. Processor 573 may be an arithmetic unit, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor). Memory 574, for example, is non-volatile or volatile memory such as RAM, ROM, flash memory, EPROM (Erasable Programmable Read-Only Memory), or EEPROM (Electrically Erasable Programmable Read-Only Memory). When learning device 300 and inference device 350 are implemented using processor 573 and memory 574, the processor 573 executes a program that describes the processes for operating learning device 300 and inference device 350, thereby realizing each of these units. The program is stored in memory 574 in advance. The program may also be stored on a storage medium. Furthermore, the program may be installed in processing circuit 571, which constitutes learning device 300 and inference device 350, from another computer or server device via a communication network.

[0217] As described above, according to the tenth embodiment, the learning device 300 generates a trained model that infers modeling result prediction information based on learning data created based on a combination of sensing data and modeling result data obtained when a modeling result under a low load and a bead having a desired shape are obtained. The inference device 350 inputs the sensing data into the trained model and outputs the modeling result prediction information. The control device 21 then adjusts at least one of the output of the laser beam L of the additive manufacturing device 100j, the feed speed of the wire W, and the current flowing through the wire W, based on the modeling result prediction information, so that the predicted value of the bead shape becomes the reference bead shape. This prevents the wire W from melting or the wire W from applying excessive stress to the workpiece.

[0218] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, or different embodiments may be combined with each other. It is also possible to omit or modify parts of the configurations as long as they do not deviate from the gist of the invention.

[0219] REFERENCE SIGNS LIST 11 Stage, 12, 12a Processing head, 13 Laser oscillator, 14 Fiber cable, 15 Gas supply device, 16 Piping, 17, 17a Wire spool, 18, 18a Rotation motor, 19 Head drive device, 20 Rotation mechanism, 21 Control device, 22 Flux application device, 23 Application drive device, 24 Flux solidification device, 25 Solidification drive device, 26 Hot wire power supply, 27 Current cable, 28 Insulating member, 29 Forming optical system, 30 Temperature measurement unit, 31 Strain gauge, 51 Base material, 52 Flux layer, 52a Liquid flux, 53 First aluminum-containing metal layer, 54 Second aluminum-containing metal layer, 55 Deposit, 61 Circuit tester, 62 Probe, 63 Imaging unit, 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h, 100i, 100j additive manufacturing apparatus, 121 beam nozzle, 122, 122a wire nozzle, 123 gas nozzle, 211 CPU, 212 RAM, 213 ROM, 214 storage device, 215 input / output interface, 216 bus, 300 learning device, 301, 351 data acquisition unit, 302 model generation unit, 303 learned model storage unit, 350 inference device, 352 inference unit, 571 processing circuit, 572 input unit, 573 processor, 574 memory, 575 output unit, G shielding gas, L laser beam, W wire, Wa flux cored wire.

Claims

1. An additive manufacturing method comprising: a first flux application step of applying a liquid flux to a base material of a metal containing iron; a first flux solidification step of heating the liquid flux applied to the base material to form a first flux layer, which is a layer in which the liquid flux has solidified; a first lamination step of irradiating a first wire, which is a wire of a metal containing aluminum, supplied onto the first flux layer, and the first flux layer with a laser beam to laminate a first aluminum-containing metal layer, which is a layer formed by melting and solidifying the first flux layer and the first wire; and a second lamination step of irradiating a second wire, which is a wire of a metal containing aluminum, supplied onto a base layer, with the laser beam after the formation of the first aluminum-containing metal layer, to laminate one or more second aluminum-containing metal layers, which are layers formed by melting and solidifying the second wire.

2. An additive manufacturing method comprising: a first lamination step of irradiating a laser beam onto a flux-containing metal wire, which is a wire containing aluminum and flux, supplied onto a base material of a metal containing iron, to laminate a first aluminum-containing metal layer, which is a layer formed by melting and solidifying the flux-containing metal wire; and a second lamination step of irradiating, after the formation of the first aluminum-containing metal layer, a metal wire, which is a wire containing aluminum supplied onto a base layer, and a portion of the base layer with the laser beam, to laminate one or more second aluminum-containing metal layers, which are layers formed by melting and solidifying the metal wire and a portion of the base layer.

3. The additive manufacturing method according to claim 1, characterized in that the second lamination process includes: a second flux application process of applying the liquid flux onto a base layer; a second flux solidification process of heating the liquid flux applied to the base layer to form a second flux layer, which is a layer in which the liquid flux has solidified; and a layer formation process of irradiating the second wire and the second flux layer supplied onto the second flux layer with the laser beam to form the second aluminum-containing metal layer, which is a layer in which the second wire and the second flux layer are melted and solidified; and wherein the processes from the second flux application process to the layer formation process are repeatedly performed, and the output of the laser beam in the layer formation process is lower than the output of the laser beam in the first lamination process.

4. The additive manufacturing method according to claim 3, characterized in that in the second flux solidification process, the second flux layer is formed by blowing hot air onto the liquid flux, irradiating the liquid flux with the laser beam, or bringing an object having a temperature equal to or higher than the solidification temperature of the liquid flux close to the liquid flux.

5. The additive manufacturing method according to claim 1, characterized in that the first wire is a metal wire containing aluminum and the flux, and the second wire is a metal wire containing aluminum but not containing the flux.

6. The additive manufacturing method according to claim 1 or 2, characterized in that in the first lamination process and the second lamination process, the wire is heated by passing an electric current through the wire.

7. An additive manufacturing method as described in any one of claims 1 to 6, characterized in that in the first and second lamination processes, the beam diameter of a laser beam emitted from a laser oscillator is widened and the laser beam is shaped to have a uniform intensity distribution.

8. The layered manufacturing method according to claim 7, wherein the laser oscillator is a semiconductor laser.

9. An additive manufacturing method as described in any one of claims 1 to 8, characterized in that in the first and second stacking processes, the temperature of the processing point, which is the irradiated position of the laser beam, is measured, and if the temperature of the processing point is higher than a predetermined reference value, the output of the laser beam is reduced.

10. The additive manufacturing method according to claim 1 or 2, characterized in that in the first lamination process and the second lamination process, the load received by the wire from the base layer is measured, and if the load is greater than a predetermined reference value, the wire feed speed is changed or the relative position between the wire and the base material is changed.

11. The additive manufacturing method according to claim 6, characterized in that in the first and second lamination processes, the current flowing through the wire is measured, and if the measured value of the current is lower than a predetermined reference value, at least one of the following processes is performed: reducing the output of the laser beam, increasing the wire feed speed, and reducing the current flowing through the wire.

12. The additive manufacturing method according to claim 6, characterized in that in the first and second lamination processes, the voltage applied to the wire is measured, and if the measured voltage value is higher than a predetermined reference value, at least one of the following processes is performed: reducing the output of the laser beam, increasing the feed speed of the wire, and reducing the current flowing through the wire.

13. The additive manufacturing method according to claim 6, characterized in that in the first lamination process and the second lamination process, the position of the tip of the wire and the position of the processing point are obtained from image data capturing an image of an area including the processing point, which is the irradiation position of the laser beam, the load that the wire receives from the base layer is measured, and at least one of the output of the laser beam, the feed speed of the wire and the current passed through the wire is adjusted depending on the position of the tip of the wire relative to the processing point and the magnitude of the load relative to a determined reference value.

14. The additive manufacturing method according to claim 6, characterized in that in the first lamination process and the second lamination process, the temperature of the tip of the wire is measured, and if the temperature of the tip of the wire is higher than a predetermined reference value, at least one of the following processes is performed: reducing the output of the laser beam, increasing the wire feed speed, and reducing the current flowing through the wire.

15. An additive manufacturing device comprising: a stage for placing a base material; a material supplying unit for supplying a wire of an aluminum-containing metal; an irradiation unit for irradiating a laser beam; a flux application unit for applying a liquid flux; a heating unit for drying the liquid flux; and a control unit, wherein the control unit controls the flux application unit to apply the liquid flux to the base material of a metal containing iron on the stage; controls the heating unit to heat the liquid flux applied to the base material to form a flux layer; controls the material supplying unit to supply the wire onto the flux layer, and controls the irradiation unit to form a first aluminum-containing metal layer by melting and solidifying the wire and the flux layer without melting the base material by irradiating it with the laser beam; and controls the material supplying unit to supply the wire onto a base layer after forming the first aluminum-containing metal layer, and controls the irradiation unit to form one or more second aluminum-containing metal layers by melting and solidifying the wire by irradiating it with the laser beam.

16. An additive manufacturing device comprising: a stage for placing a base material; a first material supply unit for supplying a flux-containing metal wire which is a wire containing aluminum and flux; a second material supply unit for supplying a metal wire which is a wire containing aluminum; an irradiation unit for irradiating a laser beam; a flux application unit for applying liquid flux; a heating unit for drying the liquid flux; and a control unit, wherein the control unit controls the first material supply unit to supply the flux-containing metal wire onto the base material of a metal containing iron on the stage, and controls the irradiation unit to form a first aluminum-containing metal layer by melting and solidifying the flux-containing metal wire by irradiating it with the laser beam; and controls the second material supply unit to supply the metal wire onto a base layer after forming the first aluminum-containing metal layer, and controls the irradiation unit to form one or more second aluminum-containing metal layers by melting and solidifying a part of the base layer and the metal wire by irradiating it with the laser beam.

17. A hot wire power supply that flows a current between the wire and the base material, a temperature measurement unit that measures the temperature of the processing point, which is the irradiated position of the laser beam, a load measurement unit that measures the load on the wire, a circuit tester that measures the current flowing through the wire or the voltage applied to the wire, an imaging unit that images an area including the processing point, and a learning device, wherein the learning device further comprises: a data acquisition unit that acquires learning data including sensing data of the additive manufacturing device including at least one of the temperature of the tip of the wire during the modeling process and the temperature of the tip of the wire before the modeling process acquired from the temperature measurement unit, the current flowing through the wire or the voltage applied to the wire acquired from the circuit tester, the position of the tip of the wire extracted from the image data acquired by the imaging unit, and the load on the wire acquired from the load measurement unit, and modeling result data showing a result when a modeling process is performed by the additive manufacturing device using the conditions obtained from the sensing data; The additive manufacturing device according to claim 15 or 16, further comprising: a model generation unit that uses the learning data to generate a learned model for inferring modeling result prediction information, which is a predicted result of the modeling process in the additive manufacturing device, from the sensing data of the additive manufacturing device.

18. A hot wire power supply that causes a current to flow between the wire and the base material, a temperature measurement unit that measures the temperature of a processing point, which is an irradiated position of the laser beam, a load measurement unit that measures a load on the wire, a circuit tester that measures the current flowing through the wire or the voltage applied to the wire, an imaging unit that images an area including the processing point, and an inference device, wherein the inference device further comprises a data acquisition unit that acquires sensing data of the additive manufacturing device, including at least one of the temperature of the tip of the wire during the modeling process and the temperature of the tip of the wire before the modeling process acquired from the temperature measurement unit, the current flowing through the wire or the voltage applied to the wire acquired from the circuit tester, the position of the tip of the wire extracted from the image data acquired by the imaging unit, and the load on the wire acquired from the load measurement unit, and an inference unit that outputs the modeling result prediction information from the sensing data input from the data acquisition unit using a trained model for inferring modeling result prediction information, which is a predicted value of the modeling result of the additive manufacturing device, from the sensing data of the additive manufacturing device, and The additive manufacturing apparatus according to claim 15 or 16, further comprising:

19. A method for manufacturing an additive manufacturing object, comprising: a first flux application step of applying a liquid flux to a base material of a metal containing iron; a first flux solidification step of forming a first flux layer, which is a layer obtained by heating and drying the liquid flux applied to the base material; a first lamination step of irradiating a first wire, which is a wire of a metal containing aluminum, supplied on the first flux layer, and the first flux layer with a laser beam to laminate a first aluminum-containing metal layer, which is a layer obtained by melting and solidifying the first flux layer and the first wire; and a second lamination step of irradiating a second wire, which is a wire of a metal containing aluminum, supplied on a base layer after the formation of the first aluminum-containing metal layer, with the laser beam to laminate one or more second aluminum-containing metal layers, which are layers obtained by melting and solidifying the second wire.

20. A method for manufacturing an additive manufacturing object, comprising: a first lamination step of irradiating a laser beam onto a flux-containing metal wire, which is a wire containing aluminum and flux, supplied onto a base material of a metal containing iron, to laminate a first aluminum-containing metal layer, which is a layer formed by melting and solidifying the flux-containing metal wire; and a second lamination step of irradiating, after the formation of the first aluminum-containing metal layer, a metal wire, which is a wire containing aluminum supplied onto a base layer, and a part of the base layer with the laser beam, to laminate one or more second aluminum-containing metal layers, which are layers formed by melting and solidifying the metal wire and a part of the base layer.

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