Additive Manufacturing Equipment

Abstract

To provide an addition production device capable of easily preheating and heat insulating a base material, a powder material, and a molten pool, and additionally producing a high quality addition product.SOLUTION: A control device 130 of an addition production device 100 controls a relative posture of a heat insulation light beam radiation device 122 to a molten light beam radiation device 121, so that a heat insulation light radiation range of a heat insulation light beam KBM larger than a molten light radiation range of a molten light beam MBM is superposed to the molten light radiation range, and magnification of the heat insulation light radiation range to magnification of the molten light radiation range can be changed. Therefore, the heat insulation light beam radiation device 122 relatively moves to the molten light beam radiation device 121, thereby independently changing the magnification of the heat insulation light radiation range of the heat insulation light beam KBM.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an additive manufacturing device. [Background technology]

[0002] Additive manufacturing is known to include, for example, Directed Energy Deposition and Powder Bed Fusion. Directed Energy Deposition performs additive manufacturing by controlling the position of a processing head that irradiates a light beam (laser beam, electron beam, etc.) and supplies material. Directed Energy Deposition methods include LMD (Laser Metal Deposition) and DMP (Direct Metal Printing). Powder Bed Fusion performs additive manufacturing by irradiating a light beam onto a flatly spread powder material. Powder Bed Fusion methods include SLM (Selective Laser Melting) and EBM (Electron Beam Melting).

[0003] For example, in the directed energy deposition method, LMD can melt and then solidify a powder material containing a hard material by spraying the powder material with a light beam. This allows LMD to be used as a build-up technology that partially adds a hard material additive to a base material.

[0004] For example, Patent Document 1 discloses an additive manufacturing device that includes a deposition head that sprays powder material and irradiates laser light, and a heating head that is fixed to move integrally with the deposition head and heats the molten powder material. In conventional additive manufacturing devices, the heating head is designed to suppress a sudden drop in temperature of the molten material powder and to create an atmosphere in which the material powder is easily melted. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2015-196265 Summary of the Invention [Problem to be solved by the invention]

[0006] In additive manufacturing, it is extremely important to properly preheat the base material and the supplied powder material, and to properly maintain the temperature of the molten pool formed by melting the powder material, in order to improve the quality of the additive product. In this regard, in the additive manufacturing device disclosed in Patent Document 1, the heating head moves together with the deposition head, that is, the heating head cannot move relative to the deposition head. For this reason, even if the heating head is used, it is extremely difficult to finely adjust the preheating (heating) of the base material and powder material, which change from moment to moment, and the temperature maintenance of the molten pool.

[0007] The present invention aims to provide an additive manufacturing apparatus that can easily preheat and keep the base material, powder material, and molten pool warm, and can additively manufacture high-quality additive products. [Means for solving the problem]

[0008] A first aspect of the present invention is a powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; An imaging device that images a state of an additive product formed on the molding surface of the base material; A control device that independently controls each of the melting light beam irradiation device and the heat-preserving light beam irradiation device with respect to the irradiation of the melting light beam and the heat-preserving light beam, and the relative scanning of the melting light beam and the heat-preserving light beam with respect to the base material, based on image data of the additive product captured by the imaging device; Equipped with The control device is in an additive manufacturing device that controls the relative attitude of the heat-preserving light beam irradiation device to the melting light beam irradiation device so that an irradiation range where the heat-preserving light beam is irradiated and which is larger than the melting light irradiation range is superimposed on the melting light irradiation range, and so that the outer size of the heat-preserving light irradiation range relative to the outer size of the melting light irradiation range is variable based on image data of the additive product imaged by the imaging device. The present invention second The embodiment includes a powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; a control device that independently controls each of the melting light beam irradiating device and the heat-keeping light beam irradiating device with respect to the irradiation of the melting light beam and the heat-keeping light beam, and the relative scanning of the melting light beam and the heat-keeping light beam with respect to the base material; Equipped with the control device controls a relative attitude of the heat-retaining light beam irradiating device with respect to the melting light beam irradiating device so that a heat-retaining light irradiation range, which is an irradiation range irradiated with the heat-retaining light beam and is larger than the melting light irradiation range, is superimposed on the melting light irradiation range, and the outer size of the heat-retaining light irradiation range with respect to the outer size of the melting light irradiation range is variable; The control device includes: controlling the attitude of the heat-keeping light beam irradiating device in a state in which the irradiation direction of the heat-keeping light beam is inclined with respect to the irradiation direction of the melting light beam; The additive manufacturing device changes the outer size of the heat-retaining light irradiation area relative to the outer size of the melting light irradiation area by changing the inclination of the heat-retaining light beam irradiation device relative to the melting light beam irradiation device. The present invention third The embodiment includes a powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; A first motor that rotates the substrate about a central axis of the substrate; A second motor that moves the base material in the direction of the central axis; a control device that independently controls each of the melting light beam irradiating device and the heat-keeping light beam irradiating device with respect to the irradiation of the melting light beam and the heat-keeping light beam, and the relative scanning of the melting light beam and the heat-keeping light beam with respect to the base material; Equipped with The control device includes: a heat-retention light irradiation range, which is an irradiation range irradiated with the heat-retention light beam and is larger than the melting light irradiation range, is superimposed on the melting light irradiation range, and a relative attitude of the heat-retention light beam irradiating device with respect to the melting light beam irradiating device is controlled so that an outer size of the heat-retention light irradiation range with respect to an outer size of the melting light irradiation range is variable; The additive manufacturing apparatus controls the relative scanning of the melting light beam and the warming light beam relative to a circumferential surface of the substrate about the central axis by controlling the rotation of the first motor and the rotation of the second motor.

[0009] According to this, the heat-preserving light beam irradiating device that irradiates the heat-preserving light beam can independently change its posture by moving relative to the melting light beam irradiating device that irradiates the melting light beam. This allows the size of the heat-preserving light irradiation range of the heat-preserving light beam to be changed independently without changing the size of the melting light irradiation range of the melting light beam. Therefore, since the range heated by the heat-preserving light beam can be freely changed, it is possible to adjust preheating (heating) according to the temperature of the base material or the temperature of the powder material that changes from moment to moment, or to maintain the heat of the molten pool formed by melting the powder material. Therefore, the additive manufacturing device can additively manufacture high-quality additive products. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 illustrates an additive manufacturing device. [Diagram 2] FIG. 2 is a diagram for explaining a movement device of the additive manufacturing apparatus of FIG. 1. [Diagram 3] 10 is a diagram for explaining a melting light irradiation range of a melting light beam and a heat-keeping light irradiation range of a heat-keeping light beam. FIG. [Figure 4] 2 is a beam profile showing the relationship between power density and light irradiation range when additively manufacturing an additive product on a substrate in the additive manufacturing apparatus of FIG. 1. [Diagram 5] 2 is a cross-sectional view showing the initial state of an additive product added to a substrate when additively manufacturing the additive product using the additive manufacturing apparatus of FIG. 1. [Figure 6] 6A to 6C are cross-sectional views showing the intermediate and added states of an additive product additively manufactured on a substrate as scanning progresses from the state shown in FIG. 5. [Figure 7] 1 is a graph for explaining a cooling rate at the solidification point of cobalt (Co) which is a cemented carbide binder. [Figure 8] 13 is a flowchart of an additive manufacturing device control program. [Figure 9] 11 is a beam profile for illustrating a change in power density of a heat-retaining light beam. [Figure 10]13A and 13B are diagrams for explaining changes in the heat-retention light irradiation range of the heat-retention light beam when preheating is suppressed. [Figure 11] 13A and 13B are diagrams for explaining changes in the heat-retaining light irradiation range of the heat-retaining light beam when preheating is intensified. [Figure 12] 13A to 13C are diagrams illustrating modified examples of the irradiation shape of the heat-keeping light beam. [Figure 13] 13A to 13C are diagrams illustrating modified examples of the irradiation shape of the heat-keeping light beam. [Figure 14] FIG. 13 is a diagram for explaining the overlap of a melting light irradiation area and a heat-retaining light irradiation area. [Figure 15] FIG. 13 is a diagram for explaining the overlap of a melting light irradiation area and a heat-retaining light irradiation area. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (1. Overview of additive manufacturing equipment) The additive manufacturing apparatus of this example employs, for example, a directed energy deposition method, an LMD method. In this example, the additive manufacturing apparatus additively manufactures a hard additive product on a substrate by spraying a powder material obtained by mixing a hard powder material, which is a hard material, with a binder powder material toward the substrate while irradiating the substrate with a light beam. The powder material, particularly the hard powder material and the substrate, may be different materials or the same type of material. Furthermore, the powder material may be a granulated powder obtained by solidifying a hard powder material and a binder powder material.

[0012] In this example, a case will be described in which a hard additive product formed using a hard powder material such as tungsten carbide (WC) which is a hard material is additively manufactured on a base material formed using carbon steel (S45C). In this example, the binding powder material is cobalt (Co) which acts as a superhard binder that binds tungsten carbide (WC). Here, the melting point (solidification point) of tungsten carbide (WC) is 2870°C, which is higher than the melting point (solidification point) of cobalt (Co) which is a superhard binder, 1495°C. In this example, cobalt (Co) is used as the superhard binder. However, the superhard binder is not limited to cobalt (Co), and for example, nickel (Ni) can also be used as the superhard binder.

[0013] (2. Configuration of additive manufacturing device 100) 1, the additive manufacturing apparatus 100 mainly includes a powder material supplying device 110, a light beam irradiation device 120, and a control device 130. The basic configuration and operation of the additive manufacturing apparatus 100 of this example are the same as those of a well-known LMD type additive manufacturing apparatus. Therefore, a detailed description of the configuration, operation, etc. of the additive manufacturing apparatus 100 will be omitted.

[0014] The powder material supplying device 110 includes a hopper 111, a valve 112, a gas cylinder 113, and an injection nozzle 114. The hopper 111 stores the hard powder material P1 mixed with the binding powder material P2. In the following description, the powder material obtained by mixing the hard powder material P1 and the binding powder material P2 is referred to as "powder material P."

[0015] The valve 112 includes a powder introduction valve 112a, a powder supply valve 112b, and a gas introduction valve 112c. The powder introduction valve 112a is connected to the hopper 111 via a pipe 111a. The powder supply valve 112b is connected to the injection nozzle 114 via a pipe 114a. The gas introduction valve 112c is connected to a gas cylinder 113 via a pipe 113a.

[0016] The injection nozzle 114 and the piping 114a are housed in a cylindrical container 115 having an inclined portion on the injection nozzle 114 side. The injection nozzle 114 is disposed at the tip of the inclined portion of the container 115. The injection nozzle 114 injects the powder material P toward the base material B, more specifically, toward the molding surface B1 on which the additive product FF is molded, via the piping 114a, using, for example, high-pressure nitrogen supplied from a gas cylinder 113. The gas for injecting the powder material P is not limited to nitrogen, and may be an inert gas such as argon.

[0017] The light beam irradiation device 120 mainly includes a melting light beam irradiation device 121, a heat-maintaining light beam irradiation device 122, and a moving device 123 that moves the melting light beam irradiation device 121 and the heat-maintaining light beam irradiation device 122 relatively and independently. Here, as shown in Fig. 1 and Fig. 2, the melting light beam irradiation device 121 and the heat-maintaining light beam irradiation device 122 are arranged so that the irradiation directions (optical axes) of the light beams irradiated by each of them cross or have a twisted positional relationship by the moving device 123. That is, as shown in Fig. 3, the melting light beam irradiation device 121 and the heat-maintaining light beam irradiation device 122 are arranged so that the irradiation range of the melting light beam MBM by the melting light beam irradiation device 121 and the irradiation range of the heat-maintaining light beam KBM by the heat-maintaining light beam irradiation device 122 overlap (overlap).

[0018] The melting light beam irradiation device 121 includes a melting light beam irradiation unit 121b that irradiates the melting light beam MBM generated and supplied by the melting light beam generation unit 121a perpendicularly to the molding surface B1 of the base material B. The melting light beam generation unit 121a is controlled by the control device 130 to generate the melting light beam MBM.

[0019] The melting light beam irradiating unit 121b is disposed in the vicinity of the injection nozzle 114 inside the container 115. Specifically, the melting light beam irradiating unit 121b is disposed at the tip of the inclined portion of the container 115 so that the melting light beam MBM can be irradiated toward the supply position of the powder material P injected from the injection nozzle 114.

[0020] The melting light beam MBM is irradiated through an optical system including a collimator lens, a condenser lens, etc. (not shown) arranged inside the container 115. Then, as shown in Fig. 1, the melting light beam MBM forms a molten pool MP by melting the powder material P supplied from the powder material supply device 110 in the base material B. Note that the "processing head" is configured to include the injection nozzle 114, the melting light beam irradiator 121, and the container 115, so that the powder material P and the melting light beam MBM move together.

[0021] The heat-preserving light beam irradiator 122 includes a heat-preserving light beam irradiator 122b that irradiates the heat-preserving light beam KBM generated and supplied by the heat-preserving light beam generator 122a onto the printing surface B1 of the base material B. The heat-preserving light beam irradiator 122 is disposed such that the irradiation direction (optical axis) of the heat-preserving light beam is inclined with respect to the irradiation direction (optical axis) of the melting light beam MBM by the melting light beam irradiator 121. The heat-preserving light beam irradiator 122 heats the base material B or the powder material P supplied onto the base material B and in an unmelted state to keep it warm.

[0022] The heat-keeping light beam generating unit 122a is controlled by the control device 130 to generate the heat-keeping light beam KBM. The heat-keeping light beam irradiating unit 122b is disposed at the tip of the cylindrical container 122c facing the substrate B. Specifically, the heat-keeping light beam irradiating unit 122b is disposed at the tip of the container 122c so that the heat-keeping light beam KBM can be irradiated so as to overlap the irradiation range of the melting light beam MBM irradiated from the melting light beam irradiating device 121. In addition, the heat-keeping light beam irradiating unit 122b is disposed at the tip of the container 122c so that the heat-keeping light beam KBM can be irradiated toward the front and rear sides, particularly at least the rear side, of the formed molten pool MP in the scanning direction of the melting light beam irradiating device 121.

[0023] The heat-preserving light beam KBM is irradiated through an optical system, such as a collimator lens and a condenser lens (not shown), arranged inside the container 122c. The heat-preserving light beam KBM preheats (heats) the forming surface B1 of the base material B and the supplied unmelted powder material P, and also keeps the molten pool MP formed by the melting light beam MBM warm.

[0024] 2, the moving device 123 mainly includes a first robot arm 123a and a second robot arm 123b. The first robot arm 123a supports the melting light beam irradiating device 121 (i.e., the processing head). The first robot arm 123a relatively displaces the melting light beam irradiating device 121 in a state in which the irradiation direction of the melting light beam MBM (i.e., the optical axis of the melting light beam MBM) is perpendicular to the forming surface B1 of the base material B.

[0025] The second robot arm 123b supports the heat-maintaining light beam irradiator 122. Specifically, the second robot arm 123b supports the heat-maintaining light beam irradiator 122 in a position in which the irradiation direction of the heat-maintaining light beam KBM (optical axis of the heat-maintaining light beam KBM) is tilted relative to the irradiation direction of the melting light beam MBM (optical axis of the melting light beam MBM), in other words, in a position in which the irradiation direction of the heat-maintaining light beam KBM (optical axis of the heat-maintaining light beam KBM) is tilted relative to the printing surface B1. Then, the second robot arm 123b displaces the heat-maintaining light beam irradiator 122 relative to the base material B, following the melting light beam irradiator 121.

[0026] Here, in this example, as shown in Fig. 3, the melting light beam irradiating device 121 irradiates the melting light beam MBM with a circular irradiation shape. The heat-keeping light beam irradiating device 122 irradiates the heat-keeping light beam KBM with a rectangular irradiation shape that overlaps with the irradiation range of the melting light beam MBM and surrounds the outside of the irradiation range of the melting light beam MBM. The length (long side or long axis) of the irradiation range of the heat-keeping light beam KBM in the scanning direction of the heat-keeping light beam KBM is set to be 1.5 times or more, preferably 2 times or more, and more preferably 3 times or more, the length of the irradiation range of the melting light beam MBM in the scanning direction of the melting light beam MBM.

[0027] As a result, the melting light beam MBM mainly melts the powder material P on the building surface B1 of the base material B, thereby additively manufacturing an additive product FF consisting of multiple beads N, as shown in Fig. 1. The heat-retention light beam KBM mainly preheats the building surface B1 of the base material B. The heat-retention light beam KBM mainly maintains heat by suppressing a drop in temperature of the additive product FF (more specifically, the molten pool MP in which the powder material P is melted) additively manufactured on the building surface B1 of the base material B.

[0028] In this example, laser light is used as the melting light beam MBM and the heat-retaining light beam KBM. However, the melting light beam MBM and the heat-retaining light beam KBM are not limited to laser light, and any electromagnetic wave, such as an electron beam, can be used. In this example, the square-shaped heat-retaining light beam KBM is irradiated so as to be superimposed on the circular melting light beam MBM, but the irradiation shape is not limited to this.

[0029] The control device 130 is a computer device whose main components include a CPU, a ROM, a RAM, an interface, etc. The control device 130 controls the powder supply of the powder material supply device 110. Specifically, the control device 130 controls the opening and closing of the powder supply valve 112b and the gas introduction valve 112c, thereby controlling the injection supply of the powder material P from the injection nozzle 114 toward the printing surface B1 of the substrate B.

[0030] The control device 130 controls the light irradiation of the light beam irradiation device 120, that is, the melting light beam irradiation device 121, the heat-keeping light beam irradiation device 122, and the moving device 123. Specifically, the control device 130 controls the operation of the melting light beam generating unit 121a of the melting light beam irradiation device 121 and the heat-keeping light beam generating unit 122a of the heat-keeping light beam irradiation device 122, respectively. In this way, the control device 130 independently controls the output conditions of the melting light beam MBM and the heat-keeping light beam KBM. Here, examples of the output conditions include the respective laser outputs, and as shown in FIG. 3, the distribution shape of the power density, which is the laser output (W) per unit area of ​​the melting light irradiation range MS, which is the irradiation range of the melting light beam MBM, and the heat-keeping light irradiation range KS, which is the irradiation range of the heat-keeping light beam KBM, i.e., the beam profile.

[0031] Here, the control device 130 controls the melting light beam MBM so that the peak MBP1 in the beam profile of the power density is increased from the peak KBP1 in the beam profile of the power density of the heat-retaining light beam KBM, as shown in Fig. 4. The laser output of the melting light beam MBM is controlled to a temperature at which the hard powder material P1 and the bonding powder material P2 can be melted to form a molten pool MP. Also, the laser output of the heat-retaining light beam KBM is controlled to a predetermined temperature at which the hard powder material P1 and the bonding powder material P2 are not melted.

[0032] Moreover, the control device 130 operates the first robot arm 123a and the second robot arm 123b of the moving device 123 to make the heat-maintaining light beam KBM follow the trajectory of the melting light beam MBM. In this case, the control device 130 can control the size of the irradiation range of the heat-maintaining light beam KBM and the angle of the optical axis of the heat-maintaining light beam KBM with respect to the optical axis of the melting light beam MBM by operating the second robot arm 123b. This allows the control device 130 to control the relative attitude of the heat-maintaining light beam irradiating device 122 with respect to the melting light beam irradiating device 121 so that the size of the irradiation range (heat-maintaining light irradiation range) of the heat-maintaining light beam KBM with respect to the size of the irradiation range (melting light irradiation range) of the melting light beam MBM is variable.

[0033] Furthermore, the control device 130 controls the relative scanning of the melting light beam MBM and the heat-keeping light beam KBM with respect to the printing surface B1 of the base material B. Specifically, in this example, the control device 130 controls the rotation of the motor M1 to rotate the base material B around the central axis C, and controls the rotation of the motor M2 to move the base material B in the direction of the central axis C. This controls the relative scanning of the melting light beam MBM and the heat-keeping light beam KBM with respect to the peripheral surface of the base material B.

[0034] In this example, the control device 130 rotates and moves the base material B. However, it goes without saying that the control device 130 can control the moving device 123 to move the melting light beam irradiating device 121 and the heat-retaining light beam irradiating device 122 relative to the molding surface B1 of the base material B.

[0035] Furthermore, the control device 130 is connected to an imaging device 140. The imaging device 140 is attached to the melting light beam irradiation device 121, and captures an image of the state of the additive product FF (bead N) formed on the molding surface B1 of the base material B. The imaging device 140 can be, for example, an infrared camera or a thermograph.

[0036] (3. Overview of additive manufacturing method for additive products FF) Next, the additive manufacturing method of the additive product FF (bead N) will be described. In the additive manufacturing method of the additive product FF (bead N), in the first step, a preheating process, which is a pretreatment in the additive manufacturing process of the additive product FF (bead N), is performed by the heat-retaining light beam KBM.

[0037] Generally, when the temperature of the printing surface B1 of the base material B is low, the thermal energy caused by the irradiation of the melting light beam MBM is likely to escape to the base material B. As a result, when additively manufacturing the additive product FF (bead N) on the printing surface B1 of the base material B in the second stage, this is likely to cause poor melting, such as insufficient melting, so in the first stage, the printing surface B1 of the base material B is preheated (heated) using the heat-retaining light beam KBM.

[0038] At this time, the heat-retaining light irradiation range KS of the heat-retaining light beam KBM in the preheating process overlaps with the melting light irradiation range MS of the melting light beam MBM (intersects with the optical axis of the melting light beam MBM) and is irradiated up to the heat-retaining light irradiation range KSF on the front side in the scanning direction SD of the melting light beam MBM (see FIG. 5). Also, the laser output of the heat-retaining light beam KBM in the preheating process is controlled so that the printing surface B1 of the base material B is at a predetermined temperature without melting.

[0039] On the other hand, for example, when the temperature of the printing surface B1 of the base material B rises and becomes high due to the formation of multiple beads N, the thermal energy caused by the irradiation of the melting light beam MBM tends to become excessive. As a result, when additively manufacturing an additive product FF (bead N) on the printing surface B1 of the base material B in the second stage, the bead width of the bead N tends to increase or the bead height tends to vary, which tends to cause additive manufacturing defects. For this reason, the preheating of the printing surface B1 of the base material B using the heat-retaining light beam KBM is suppressed in the first stage.

[0040] At this time, the heat-retaining light irradiation range KS of the heat-retaining light beam KBM in the preheating process overlaps with the melting light irradiation range MS (intersects with the optical axis of the melting light beam MBM). Here, the power density of the heat-retaining light beam KBM is smaller than the power density of the melting light beam MBM. Therefore, the effect of the melting light beam MBM on the melting of the powder material P is small.

[0041] 5 and 6, in the second stage, a melting process is performed in which a part of the building surface B1 of the base material B and the powder material P are melted in the melting light irradiation range MS by irradiating the melting light beam MBM to form a molten pool MP. In this melting process, a preheating process is performed as a pretreatment for the process of forming the molten pool MP by a part of the heat-retaining light beam KBM in the heat-retaining light irradiation range KSF in front of the melting light beam MBM in the scanning direction SD of the melting light beam MBM, among the heat-retaining light irradiation range KS of the heat-retaining light beam KBM.

[0042] Then, as shown in Fig. 6, the melting light beam MBM is scanned in the scanning direction SD (in this example, the substrate B is rotated to perform scanning, but for convenience in Fig. 6, the melting light beam MBM is used to scan), expanding the molten pool MP, thereby additively manufacturing an additive product FF (bead N). Here, the additive product FF (bead N) in this example is formed by binding tungsten carbide (WC) of the hard powder material P1 with cobalt (Co) of the binding powder material P2, which acts as a superhard binder. The additive product FF in this example is composed of multiple beads N formed in stripes along the circumferential direction of the substrate B (see Fig. 1).

[0043] In addition, the melting light beam MBM melts the powder material P so as to expand the molten pool MP, and then moves sequentially in the scanning direction SD. Therefore, a part of the heat-retention light beam KBM irradiates the molten pool MP in the heat-retention light irradiation range KSB behind the melting light beam MBM in the scanning direction SD of the melting light beam MBM, out of the heat-retention light irradiation range KS of the heat-retention light beam KBM. As a result, the heat-retention light beam KBM performs heat-retention processing as a post-processing of additive manufacturing of the additive product FF.

[0044] However, as described above, when the temperature of the modeling surface B1 of the base material B is high due to the formation of multiple beads N, the thermal energy caused by the irradiation of the melting light beam MBM may become excessive. In this case, the control device 130 reduces the heat-retaining light irradiation range KS. However, in order to continue the heat-retaining process, the control device 130 irradiates the heat-retaining light beam KBM to a heat-retaining light irradiation range KSB on the rear side, which overlaps with the melting light irradiation range MS (i.e., intersects with the optical axis of the melting light beam MBM).

[0045] Here, the effect of preheating (and keeping warm) will be explained. As shown in the diagram of the temperature change over time in the additive product FF in FIG. 7, when the substrate B is not preheated (shown by the dashed line in FIG. 7), the temperature of the additive product FF drops rapidly after it is heated to exceed the freezing point, i.e., melting point, of cobalt (Co). In other words, when there is no preheating, the thermal energy given in advance after solidification is relatively small. Therefore, as shown by the thick two-dot chain line in FIG. 7, the cooling rate (°C / s) representing the temperature drop per unit time at the freezing point of cobalt (Co), i.e., the slope of the tangent at the freezing point of cobalt (Co), becomes large, resulting in rapid cooling.

[0046] On the other hand, when the base material B is preheated and the preheat temperature (heating temperature) is 600°C or higher (shown by the solid line in FIG. 7), the temperature of the additive product FF slowly drops after it is heated to exceed the freezing point, i.e., melting point, of cobalt (Co). In other words, when there is preheating, the thermal energy given in advance after solidification is relatively large. Therefore, as shown by the thick two-dot chain line in FIG. 7, the cooling rate (°C / s) at the freezing point of cobalt (Co) is smaller than when there is no preheating.

[0047] Therefore, by appropriately setting the cooling rate (℃ / s) at the freezing point of cobalt (Co) of the binding powder material P2, cracking of the additive product FF can be suppressed. Specifically, when the base material B is preheated (and kept warm) so that the cooling rate (℃ / s) at the freezing point of cobalt (Co) is 540℃ / s or less, rapid cooling of the additive product FF is prevented, and cracking of the additive product FF can be suppressed.

[0048] For this reason, the control device 130 sets the beam profile of the power density of the heat-retaining light beam KBM so that the cooling rate is 540°C / s or less, and controls the operation of the heat-retaining light beam irradiating device 122. As a result, in the heat-retaining light irradiation range KS where the heat-retaining light beam KBM is irradiated, the cooling rate becomes 540°C / s or less, in other words, the temperature is kept at 600°C or more, and rapid cooling is prevented. As a result, cracking of the additive product FF can be suppressed.

[0049] (4. Details of additive manufacturing method for additive products FF) Next, the additive manufacturing method of the additive product FF will be described in detail. The control device 130 starts the execution of the additive manufacturing device control program shown in Fig. 8 in step S10, and in the following step S11, the control device 130 controls the operation of the powder material supply device 110. That is, the control device 130 controls the opening and closing of the valve 112 of the powder material supply device 110, specifically, the powder supply valve 112b and the gas introduction valve 112c, and supplies a preset supply amount of powder material P from the injection nozzle 114 to the base material B. Then, when the control device 130 supplies the powder material P to the base material B, it executes the step processing of step S12.

[0050] In step S12, the control device 130 operates the melting light beam irradiating device 121 and the heat-preserving light beam irradiating device 122 of the light beam irradiating device 120. Then, the control device 130 irradiates the powder material P supplied to the base material B in step S11 with the melting light beam MBM and the heat-preserving light beam KBM, and additively manufactures a bead N, i.e., an additive product FF, on the forming surface B1 of the base material B.

[0051] In step S13, the control device 130 acquires image data G of the bead N captured by the imaging device 140. Then, the control device 130 executes the step process of step S14. Note that the control device 130 is not limited to acquiring image data G that is a still image, and may acquire video data that is a video captured by the imaging device 140, for example.

[0052] In step S14, the control device 130 determines whether the bead width W, which represents the width of the bead N, is stable as the formation state of the formed bead N, based on the image data G (or video data) acquired in step S13. Specifically, when the bead width W is within a range defined by a preset minimum bead width WL and a preset maximum bead width WH, the bead width W is stable. On the other hand, when the bead width W is outside the range defined by the minimum bead width WL and the maximum bead width WH, the bead width W is unstable.

[0053] Therefore, when the bead width W is equal to or greater than the minimum bead width WL and less than the maximum bead width WH, the control device 130 judges "Yes" in step S14 and executes the step processing of step S15. On the other hand, when the bead width W is less than the minimum bead width WL or is equal to or greater than the maximum bead width WH, the control device 130 judges "No" in step S14. Then, the control device 130 executes the step processing of step S12.

[0054] As described above, when the bead width W is equal to or greater than the maximum bead width WH, the temperature of the base material B due to the preheating process may have increased, and the energy applied when the melting light beam MBM was irradiated may have been excessive. In other words, when the energy is excessive, the supplied powder material P melts excessively, and the molten pool MP becomes large, and as a result, the bead width W becomes equal to or greater than the maximum bead width WH. On the other hand, when the bead width W is less than the minimum bead width WL, the temperature of the base material B due to the preheating process may have been low, and insufficient melting may have occurred. In other words, when insufficient melting occurs, the molten pool MP becomes small, and as a result, the bead width W becomes less than the minimum bead width WL.

[0055] Therefore, when executing the step process of step S12 according to the determination process of "No" in step S14, the control device 130 adjusts the operation of the light beam irradiation device 120 depending on whether the bead width W is equal to or larger than the maximum bead width WH or the bead width W is smaller than the minimum bead width WL. A specific description will be given below.

[0056] When the bead width W is equal to or larger than the maximum bead width WH, as described above, the main cause is excessive energy from the light beam irradiation device 120. For this reason, the control device 130 reduces the power density of the heat-keeping light beam KBM to reduce the energy caused by preheating the substrate B. Also, if necessary, the power density of the melting light beam MBM is reduced to reduce the molten pool MP. In this case, the control device 130 reduces the peak KBP1 in the beam profile of the power density of the heat-keeping light beam KBM, as shown in FIG. 9.

[0057] Alternatively, the control device 130 operates the second robot arm 123b of the moving device 123 to reduce the energy used for preheating the base material B, thereby reducing the heat-retaining light irradiation range KS (reducing the front heat-retaining light irradiation range KSF) as shown in Fig. 10. In this case, the control device 130 operates the second robot arm 123b to, for example, reduce the inclination (reduce the angle) of the optical axis of the heat-retaining light beam KBM relative to the optical axis of the melting light beam MBM. This makes it possible to reduce the heat-retaining light irradiation range KS.

[0058] Even in this case, the control device 130 keeps the molten pool MP warm by the heat-keeping light irradiation range KSB on the rear side of the heat-keeping light beam KBM. This prevents the formed molten pool MP from being rapidly cooled, and prevents cracks from occurring in the formed additive product FF (bead N).

[0059] On the other hand, when the bead width W is less than the minimum bead width WL, the main cause is insufficient preheating, as described above. Therefore, the control device 130 increases the output of the heat-keeping light beam KBM to increase the energy by preheating the substrate B. In this case, the control device 130 increases the peak KBP1 in the beam profile of the power density of the heat-keeping light beam KBM in the beam profile shown in FIG.

[0060] Alternatively, the control device 130 operates the second robot arm 123b of the moving device 123 to increase the energy by preheating the base material B, thereby enlarging the heat-retaining light irradiation range KS (relatively enlarging the front heat-retaining light irradiation range KSF) as shown in Fig. 11. In this case, the control device 130 operates the second robot arm 123b to, for example, increase the inclination (increase the angle) of the optical axis of the heat-retaining light beam KBM relative to the optical axis of the melting light beam MBM. This makes it possible to enlarge the heat-retaining light irradiation range KS, and to satisfactorily preheat the modeling surface B1 of the base material B.

[0061] In this case, the control device 130 operates the second robot arm 123b to, for example, relatively move the heat-maintaining light beam irradiator 122 in a direction away from the substrate B, and increase the output of the heat-maintaining light beam KBM. As a result, the heat-maintaining light irradiation range KS becomes larger as the heat-maintaining light beam irradiator 122 moves relatively away from the substrate B. When the heat-maintaining light irradiation range KS becomes larger, the power density relatively decreases, and the output of the heat-maintaining light beam KBM is increased. As a result, the front heat-maintaining light irradiation range KSF can be relatively large, and the substrate B can be well preheated by the heat-maintaining light beam KBM in the heat-maintaining light irradiation range KSF.

[0062] Even in this case, the control device 130 keeps the molten pool MP warm by the heat-keeping light irradiation range KSB on the rear side of the heat-keeping light beam KBM. This prevents the formed molten pool MP from being rapidly cooled, and prevents cracks from occurring in the formed additive product FF (bead N).

[0063] After adjusting the operation of the light beam irradiation device 120 and the moving device 123 in accordance with the bead width W, the control device 130 operates the light beam irradiation device 120 in accordance with the adjusted operation, and then executes the respective step processes from step S13 onwards again.

[0064] On the other hand, if the determination in step S14 shown in Fig. 8 is "Yes," the control device 130 executes the step processing in step S15. That is, in step S15, the control device 130 determines whether the bead height H, which represents the height of the bead N, is stable as the formation state of the formed bead N based on the image data G (or video data) acquired in step S13. Specifically, when the bead height H is within a range defined by a preset minimum bead height HL and a maximum bead height HH, the bead height H is stable. On the other hand, when the bead height H is outside the range defined by the minimum bead height HL and the maximum bead height HH, the bead height H is unstable.

[0065] Therefore, when the bead height H is equal to or greater than the minimum bead height HL and less than the maximum bead height HH, the control device 130 judges "Yes" in step S15 to continue forming the bead N, i.e., the additive product FF, and ends the execution of the program in step S16 when the formation of the additive product FF is completed. On the other hand, when the bead height H is less than the minimum bead height HL or the bead height H is equal to or greater than the maximum bead width WH, the control device 130 judges "No" in step S15. Then, the control device 130 executes the step process of step S11.

[0066] When the bead height H is equal to or greater than the maximum bead height HH, there is a possibility that the amount of powder material P supplied to the substrate B is excessive. That is, the amount of powder material P supplied is excessive and the supplied powder material P melts, causing the bead height H to be equal to or greater than the maximum bead height HH. On the other hand, when the bead height H is less than the minimum bead height HL, there is a possibility that the amount of powder material P supplied to the substrate B is too small. That is, even if the amount of powder material P supplied is too small and all of the supplied powder material P is melted, the bead height H will be less than the minimum bead height HL.

[0067] Therefore, when executing the step process of step S11 according to the judgment process of "No" in step S15, the control device 130 adjusts the supply amount of the powder material P supplied from the powder material supply device 110 depending on whether the bead height H is equal to or greater than the maximum bead height HH or the bead height H is less than the minimum bead height HL. A specific description will be given below.

[0068] When the bead height H is equal to or greater than the maximum bead height HH, as described above, the main cause is an excessive supply amount of the powder material P supplied from the powder material supplying device 110. For this reason, the control device 130 reduces the supply amount of the powder material P supplied to the substrate B. That is, the control device 130 reduces the opening of the valve 112 of the powder material supplying device 110, specifically, the powder supply valve 112b and the gas introduction valve 112c. In this case, the control device 130 can also increase the scanning speed of the processing head without changing the supply amount of the powder material P so as to reduce the supply amount per unit length of the bead N.

[0069] On the other hand, when the bead height H is less than the minimum bead height HL, as described above, the main cause is an insufficient supply amount of the powder material P supplied from the powder material supply device 110. For this reason, the control device 130 increases the supply amount of the powder material P supplied to the substrate B. That is, the control device 130 increases the opening of the valve 112 of the powder material supply device 110, specifically, the powder supply valve 112b and the gas introduction valve 112c. In this case, the control device 130 can also reduce the scanning speed of the processing head without changing the supply amount of the powder material P so that the supply amount per unit length of the bead N increases.

[0070] When the control device 130 adjusts the operation of the powder material supplying device 110 in accordance with the bead height H, the control device 130 operates the powder material supplying device 110, specifically, the valve 112, in accordance with the adjusted operation. Then, the control device 130 executes the respective step processes from step S12 onward again.

[0071] As can be understood from the above description, according to the additive manufacturing apparatus 100, the heat-retaining light beam irradiating device 122 that irradiates the heat-retaining light beam KBM can independently change its posture by moving relative to the melting light beam irradiating device 121 that irradiates the melting light beam MBM. This allows the size of the heat-retaining light irradiation range KS of the heat-retaining light beam KBM to be changed independently without changing the size of the melting light irradiation range MS of the melting light beam MBM. Therefore, since the range heated by the heat-retaining light beam KBM can be freely changed, for example, preheating (heating) can be adjusted according to the temperature of the modeling surface B1 of the base material B, which changes from moment to moment, or the heat retention of the molten pool MP formed by melting the powder material P can be adjusted. Therefore, the additive manufacturing apparatus 100 can additively manufacture a high-quality additive product FF.

[0072] (5. Other) In the above-mentioned embodiment, the irradiation shape of the melting light beam MBM is circular. However, the irradiation shape of the melting light beam MBM can also be, for example, polygonal. In the above-mentioned embodiment, the irradiation shape of the heat-maintaining light beam KBM is rectangular. However, the irradiation shape of the heat-maintaining light beam KBM can also be, for example, an elliptical shape (circular shape) as shown in FIG. 12, a circular shape (or a square ring shape, etc.) so as to include the melting light beam MBM as shown in FIG. 13, or a polygonal shape other than a rectangle. Furthermore, the melting light beam MBM and the heat-maintaining light beam KBM only need to overlap at least partially as shown in FIG. 14 and FIG. 15. In these cases, the same effects as those of the above-mentioned embodiment can be expected.

[0073] In the above-mentioned embodiment, the powder material P consisting of the hard powder material P1 and the binding powder material P2 is sprayed and supplied to the printing surface B1 of the base material B by the powder material supplying device 110 in the additive manufacturing device 100. However, the material supply to the printing surface B1 is not limited to the powder material P, and it is also possible to supply, for example, a wire or the like consisting of a metal linear material by the material supplying device. In this case, the supplied linear material is melted by the melting light beam MBM irradiated from the light beam irradiating device 120 and is kept warm by the heat-retaining light beam KBM, so that an additive product FF can be additively manufactured on the printing surface B1 of the base material B. Therefore, the same effect as that of the above-mentioned embodiment can be expected.

[0074] Furthermore, in the above-mentioned embodiment and the like, the additive manufacturing apparatus 100 has been described as adopting the LMD method. Instead, even if the additive manufacturing apparatus adopts the SLM method, the heat-retaining light beam can keep the molten pool (additive product) warm. However, when the SLM method is adopted, the scanning speed of the light beam is usually faster than the scanning speed of the LMD light beam. For this reason, when the additive manufacturing apparatus adopts the SLM, it is preferable to, for example, slow down the scanning speed of the melting light beam and the heat-retaining light beam compared to normal additive manufacturing. The slower the scanning speed, the more the heat-retaining effect of the heat-retaining light beam KBM is exerted. [Explanation of symbols]

[0075] 100...additive manufacturing apparatus, 110...powder material supply apparatus, 111...hopper, 111a...piping, 112...valve, 112a...powder introduction valve, 112b...powder supply valve, 112c...gas introduction valve, 113...gas cylinder, 113a...piping, 114...spray nozzle, 114a...piping, 115...container, 120...light beam irradiation device, 121...melting light beam irradiation device, 121a...melting light beam generation unit, 121b...melting light beam irradiation unit, 122...heat-retaining light beam irradiation device, 122a...heat-retaining light beam generation unit, 122b...heat-retaining light beam irradiation unit, 122c...container, 123...moving device, 123a...first robot arm, 123 b...second robot arm, 130...control device, 140...imaging device, B...base material, B1...build surface, C...central axis, FF...additive product, N...bead, MP...molten pool, KBM...heat retention light beam, MBM...melt light beam, MS...melt light irradiation range, KS...heat retention light irradiation range, KSB...rear heat retention light irradiation range, KSF...front heat retention light irradiation range, M1...motor, M2...motor, P...powder material, P1...hard powder material, P2...bonded powder material, G...image data, SD...scanning direction, SS...outer light irradiation range, W...bead width, WH...maximum bead width, WL...minimum bead width, H...bead height, HH...maximum bead height, HL...minimum bead height

Claims

1. A powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; An imaging device that images a state of an additive product formed on the molding surface of the base material; A control device that independently controls each of the melting light beam irradiation device and the heat-preserving light beam irradiation device with respect to the irradiation of the melting light beam and the heat-preserving light beam, and the relative scanning of the melting light beam and the heat-preserving light beam with respect to the base material, based on image data of the additive product captured by the imaging device; Equipped with The control device controls the relative attitude of the heat-preserving light beam irradiation device to the melting light beam irradiation device so that a heat-preserving light irradiation range, which is an irradiation range irradiated with the heat-preserving light beam and is larger than the melting light irradiation range, is superimposed on the melting light irradiation range, and so that the outer size of the heat-preserving light irradiation range relative to the outer size of the melting light irradiation range is variable based on image data of the additive product imaged by the imaging device.

2. The outer shape of the heat-retaining light irradiation range is a rectangle having a long side along the scanning direction of the heat-retaining light beam, or an ellipse having a long axis along the scanning direction of the heat-retaining light beam, The additive manufacturing device according to claim 1 , wherein the control device controls the relative attitude of the heat-preserving light beam irradiator with respect to the melting light beam irradiator based on the image data so that the longitudinal length of the heat-preserving light beam is variable.

3. The control device includes: controlling the attitude of the heat-keeping light beam irradiating device in a state in which the irradiation direction of the heat-keeping light beam is inclined with respect to the irradiation direction of the melting light beam; The additive manufacturing device of claim 2 , wherein the longitudinal length of the heat-preserving light beam is changed by changing an inclination of the heat-preserving light beam irradiator relative to the melting light beam irradiator based on the image data.

4. The control device includes: controlling the attitude of the heat-keeping light beam irradiating device in a state in which the irradiation direction of the heat-keeping light beam is inclined with respect to the irradiation direction of the melting light beam; The additive manufacturing device of claim 1 , wherein the inclination of the heat-retaining light beam irradiating device relative to the melting light beam irradiating device is changed based on the image data, thereby changing the outer size of the heat-retaining light irradiation area relative to the outer size of the melting light irradiation area.

5. the heat-retaining light irradiation range includes a region in front of a front end of the melting light irradiation range in the scanning direction of the melting light beam, and includes a region in rear of a rear end of the melting light irradiation range in the scanning direction of the melting light beam, The additive manufacturing device according to any one of claims 1 to 4, wherein the control device controls the relative attitude of the heat-preserving light beam irradiating device with respect to the melting light beam irradiating device based on the image data so that the length of the front region in the scanning direction of the melting light beam in the heat-preserving light irradiation range is variable.

6. The additive manufacturing device according to any one of claims 1 to 5, wherein the control device controls the relative attitude of the heat-retaining light beam irradiating device with respect to the melting light beam irradiating device so that the outer size of the heat-retaining light irradiation area relative to the outer size of the melting light irradiation area is variable based on the bead width of the additive product in the image data.

7. A powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; a control device that independently controls each of the melting light beam irradiating device and the heat-keeping light beam irradiating device with respect to the irradiation of the melting light beam and the heat-keeping light beam, and the relative scanning of the melting light beam and the heat-keeping light beam with respect to the base material; Equipped with the control device controls a relative attitude of the heat-retaining light beam irradiating device with respect to the melting light beam irradiating device so that a heat-retaining light irradiation range, which is an irradiation range irradiated with the heat-retaining light beam and is larger than the melting light irradiation range, is superimposed on the melting light irradiation range, and the outer size of the heat-retaining light irradiation range with respect to the outer size of the melting light irradiation range is variable; The control device includes: controlling the attitude of the heat-keeping light beam irradiating device in a state in which the irradiation direction of the heat-keeping light beam is inclined with respect to the irradiation direction of the melting light beam; An additive manufacturing device that changes the outer size of the heat-retaining light irradiation area relative to the outer size of the melting light irradiation area by changing the inclination of the heat-retaining light beam irradiation device relative to the melting light beam irradiation device.

8. The outer shape of the heat-retaining light irradiation range is a rectangle having a long side along the scanning direction of the heat-retaining light beam, or an ellipse having a long axis along the scanning direction of the heat-retaining light beam, The additive manufacturing device of claim 7 , wherein the control device changes the longitudinal length of the heat-preserving light beam by changing an inclination of the heat-preserving light beam irradiator relative to the melting light beam irradiator.

9. A powder material supplying device that supplies a powder material including a hard material, which is tungsten carbide (WC), and a superhard binder, which is cobalt (Co) or nickel (Ni), to a substrate; a melting light beam irradiation device that irradiates the powder material supplied to the base material with a melting light beam to heat the powder material to a melting point or higher and melt the powder material; a heat-retaining light beam irradiating device that irradiates a heat-retaining light beam that heats and keeps the temperature below the melting point outside a melting light irradiation range that is an irradiation range where the melting light beam is irradiated; A first motor that rotates the substrate about a central axis of the substrate; A second motor that moves the base material in the direction of the central axis; a control device that independently controls each of the melting light beam irradiating device and the heat-keeping light beam irradiating device with respect to the irradiation of the melting light beam and the heat-keeping light beam, and the relative scanning of the melting light beam and the heat-keeping light beam with respect to the base material; Equipped with The control device includes: a heat-retention light irradiation range, which is an irradiation range irradiated with the heat-retention light beam and is larger than the melting light irradiation range, is superimposed on the melting light irradiation range, and a relative attitude of the heat-retention light beam irradiating device with respect to the melting light beam irradiating device is controlled so that an outer size of the heat-retention light irradiation range with respect to an outer size of the melting light irradiation range is variable; An additive manufacturing apparatus that controls the relative scanning of the melting light beam and the warming light beam relative to a circumferential surface of the substrate about the central axis by controlling the rotation of the first motor and the rotation of the second motor.

10. An additive manufacturing device according to any one of claims 1 to 9, wherein the irradiation direction of the melting light beam is a direction perpendicular to a building surface that builds an additive product on the substrate.

11. An additive manufacturing device according to any one of claims 7 to 9, wherein the heat-preserving light irradiation range is rectangular in shape having long sides aligned with the scanning direction of the heat-preserving light beam.

12. An additive manufacturing device according to any one of claims 7 to 9, wherein the heat-preserving light irradiation range is elliptical in shape having a major axis along the scanning direction of the heat-preserving light beam.

13. An additive manufacturing apparatus according to any one of claims 7 to 9, wherein the heat-retaining light irradiation area is annular and contains the circular melting light irradiation area therein.

14. An additive manufacturing device as described in any one of claims 7 to 9, wherein the outer shape of the heat-retaining light irradiation range includes a front region that is further forward than the front end of the melting light irradiation range in the scanning direction of the melting light beam, and includes a rear region that is further forward than the rear end of the melting light irradiation range in the scanning direction of the melting light beam, and the rear region is longer than the front region in the scanning direction of the melting light beam.

15. The control device includes: An additive manufacturing device described in any one of claims 1 to 14, wherein when the heat-retaining light beam irradiates a molten pool formed by irradiating the melting light beam to melt the powder material, the power density representing the output per unit area of ​​the heat-retaining light beam is controlled so that a cooling rate representing a temperature decrease per unit time in the molten pool is 540°C / s or less at the freezing point of the carbide binder contained in the molten pool.

16. The control device includes: The additive manufacturing apparatus of claim 15, wherein the power density of at least the heating light beam is altered based on a temperature of the powder material on the substrate.

17. 17. The additive manufacturing apparatus of claim 15 or 16, wherein the heating light beam heats the substrate to 600°C or greater.

18. An additive manufacturing device according to any one of claims 15 to 17, wherein the control device controls the power density of the warming light beam at least rearwardly relative to the direction of scanning of the melting light beam.

19. An additive manufacturing apparatus according to any one of claims 1 to 18, wherein the powder material supplying device supplies the powder material to the substrate by spraying it, and is movably arranged integrally with the melting light beam irradiation device.

20. An additive manufacturing device described in any one of claims 1 to 19, wherein the control device controls the scanning of the heat-preserving light beam irradiated by the heat-preserving light beam irradiator so as to follow the trajectory of the scanning of the melting light beam irradiated by the melting light beam irradiator.

21. The additive manufacturing apparatus of any one of claims 1 to 20, wherein the heat-keeping light beam irradiation device heats the substrate to keep it warm.

22. An additive manufacturing apparatus according to any one of claims 1 to 21, wherein the melting point of the hard material is higher than the melting point of the ultra-hard binder.

Images