JP2010121187A - Three-dimensional shaped article and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional shaped article such as a die and a method for producing the three-dimensional shaped article, with which the structure of the shaped article is simple, and temperature control in the cooling process of a melted resin or the like is made possible without depending on heat generation by a heater or the like. <P>SOLUTION: In the method for producing a three-dimensional shaped article, a powder layer forming stage where a powder material 2 is fed so as to form a powder layer 21 and a hardened layer forming stage where the powder layer 21 is sintered or melted so as to form a hardened layer 22 are repeated so as to shape a three-dimensional shaped article 5 in which the hardened layers 22 are laminated and integrated, and distribution is given to thermal conductivity at the inside of the shaped article. In this way, the shaped article (such as die) which can optimize the cooling temperature of a resin by controlling the thermal conductivity at the inside thereof, and can suppress occurrence of the warpage or the like of a molded part can be obtained. Further, regarding the die produced by the method, the temperature control in its inside is made possible by a simple structure without providing a duct, a flow passage or the like in the inside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a three-dimensional structure such as a mold formed by irradiating a powder material with a light beam to sinter or melt it, and a manufacturing method thereof.

  Conventionally, a powder layer forming step for forming a powder layer and a cured layer forming step for irradiating the powder layer with a light beam to sinter a predetermined portion of the powder layer to form a hardened layer are repeated. A method of manufacturing a three-dimensional structure by laminating is known (for example, see Patent Document 1). According to this method, for example, it is possible to integrally form a mold for injection molding, which requires combining a plurality of parts in conventional cutting.

  By the way, in injection molding using a mold, when the molded product has a locally thick part or when molding a molded product that causes warpage or optical distortion, it is injected into the mold. The cooling process of the molten resin and the like greatly affects the quality of the molded product. For example, in the injection molding of a resin molded product, a molten resin (usually about 150 to 300 ° C.) is injected and filled into a mold, and then the resin is cooled by being transferred to the mold. To complete the molding.

  However, the thick-walled portion of the resin molded product is more likely to accumulate heat than the thin-walled portion, and the resin is less likely to be cooled. Therefore, if the temperature change of the mold itself is constant, the cooling rate of the entire resin locally changes depending on the shape of the molded product, which causes warpage and distortion of the molded product. Therefore, in order to obtain a high-quality molded product, local temperature adjustment in the mold is required in the resin cooling process.

For such temperature adjustment in the mold, a method of raising the temperature by heating the heater or a method of flowing a temperature adjustment medium such as water or an organic aqueous solution into the mold is used. For example, a cooling medium is made to flow in a mold part that molds a thick-walled part where the heat of the resin is easily trapped and is slow to cool, and heater heating or the like is performed on a mold part that molds a thin-walled part that is quickly cooled. Thereby, the cooling rate as the whole resin molded product is made uniform, and the generation | occurrence | production of the curvature and distortion of a molded product can be suppressed. The above-described method for manufacturing a three-dimensional structure is also suitable for integrally forming a duct for heater installation and a flow path for a temperature control medium in a mold.
Japanese Patent No. 2620353

  However, if a duct or a flow path is provided in the mold, the structure inside the mold becomes complicated, so that the mold design is not easy and the degree of freedom of the mold that can be formed is limited. In addition, trial and error due to repeated design trials and molding trials of the mold increases. If it becomes so, the lead time of molded product development until the molded product which satisfy | fills the required quality will become long. In addition, according to the temperature control method described above, a large amount of energy such as electric power is consumed for heater heating, heating or cooling of the temperature control medium, and flow of the temperature control medium, which is not preferable from the viewpoint of energy saving. .

  The present invention solves the above-described problem, and has a simple structure and a three-dimensional structure such as a mold that enables temperature adjustment in a cooling process of a molten resin or the like without depending on a method such as heater heating. It aims at providing the manufacturing method of the three-dimensional structure.

  In order to solve the above-mentioned problems, the invention of claim 1 includes a powder layer forming step of supplying a powder material to form a powder layer, and irradiating a predetermined portion of the powder layer with a light beam to sinter the powder layer. Alternatively, in the three-dimensional structure manufacturing method of forming a three-dimensional structure by stacking and integrating the hardened layer or the powder layer by repeating a hardened layer forming step of forming a hardened layer by melting, the three-dimensionally formed tertiary Distribution is given to the thermal conductivity inside the original model.

  Invention of Claim 2 is a manufacturing method of the three-dimensional structure of Claim 1, Comprising: In the said hardening layer formation process, the heat conduction inside a three-dimensional structure by controlling the hardening density of the said hardening layer. A distribution is given to the rate.

  Invention of Claim 3 is a manufacturing method of the three-dimensional structure of Claim 1 or Claim 2, Comprising: In the said hardened layer formation process, three-dimensional modeling is provided by providing an unsintered part or an unmelted part. It gives distribution to the thermal conductivity inside the object.

  Invention of Claim 4 is a manufacturing method of the three-dimensional structure as described in any one of Claim 1 thru | or 3, Comprising: It distributes to the thermal conductivity inside a three-dimensional structure by providing a cavity part. It is something to have.

  According to a fifth aspect of the present invention, in the method for manufacturing a three-dimensional structure according to the fourth aspect, the hollow portion is filled with a material having a thermal conductivity different from that of the powder material.

  Invention of Claim 6 is a manufacturing method of the three-dimensional structure of Claim 1, Comprising: In the said powder layer formation process, the inside of a three-dimensional structure is controlled by controlling the material of the said powder material and its mixture. It gives a distribution to the thermal conductivity.

  According to a seventh aspect of the present invention, in the method for manufacturing a three-dimensional structure according to any one of the first to third aspects, the high thermal conductivity portion having a high thermal conductivity is formed in the cell structure. In addition, a low thermal conductivity portion having a low thermal conductivity is formed in the high thermal conductivity portion of the cell structure.

  The invention of claim 8 is the method for producing a three-dimensional structure according to claim 6, wherein a low thermal conductivity portion having a low thermal conductivity is formed in the cell structure, and in the low thermal conductivity portion of the cell structure, A high thermal conductivity part with high thermal conductivity is formed.

  The invention of claim 9 is the method for manufacturing a three-dimensional structure according to any one of claims 1 to 3 or claim 6 to claim 8, wherein the heat inside the three-dimensional structure that is integrally formed. The conductivity is changed in an inclined manner.

  The invention of claim 10 is a three-dimensional structure manufactured by the method for manufacturing a three-dimensional structure according to any one of claims 1 to 9.

  According to the present invention, the cooling temperature of the resin can be optimized by changing the curing density inside the molded article (for example, a mold) to control the thermal conductivity, and the occurrence of warpage of the molded product is caused. A shaped object (mold) that can be suppressed is obtained. Further, according to this method, the temperature inside the mold can be adjusted with a simple structure without providing a duct or a flow path in the mold.

  Hereinafter, a method for manufacturing a three-dimensional structure according to the first embodiment of the present invention (hereinafter referred to as a method for manufacturing a three-dimensional object) will be described with reference to the drawings. FIG. 1 shows the configuration of a metal stereolithography machine (hereinafter referred to as an optical modeling machine 1) used in the manufacturing method of this embodiment, and FIGS. 2 (a) to 2 (c) show the operation of the optical molding machine 1. FIG. The optical modeling machine 1 supplies a powder material 2 (for example, spherical iron powder having an average particle diameter of 20 μm) to form a powder layer 21 and a light beam L1 at a predetermined position of the powder layer 21. Is applied to the cured layer forming part 4 for forming the cured layer 22 by sintering or melting the powder layer 21 and the three-dimensional structure (hereinafter referred to as the model 5) formed by the accumulation of the cured layer 22. The cutting removal part 6 to be provided is provided.

  The powder layer forming unit 3 includes a modeling plate (hereinafter referred to as a plate 31 (see FIG. 2)) on which the powder layer 21 of the powder material 2 is laid, and a lifting table 32 (substrate) that holds the plate 31 and moves up and down. A mounting table (see FIG. 2)) and a modeling tank 33 that accommodates the plate 31 and the lifting table 32 are provided. Further, the powder layer forming unit 3 stores the powder material 2 and forms a powder layer 21 by laying the powder material 2 that lifts the powder material 2 on the plate 31. A powder supply plate 35. The plate 31 is made of carbon steel such as S55C, for example.

  The hardened layer forming unit 4 includes a light beam oscillator 41 that emits a light beam L1, a condensing lens 42 that condenses the emitted light beam L1, and the condensed light beam L1 on the powder layer 21. And a galvanometer mirror 43 for scanning. As the light beam L1, for example, a carbon dioxide gas beam, an Nd-YAG light beam, or the like is used, and its output is, for example, approximately 500W. The cutting removal unit 6 includes a cutting tool 61 that cuts the shaped article 5, a milling head 62 that holds the cutting tool 61, and an XY drive mechanism 63 that moves the milling head 62.

  The optical modeling machine 1 also includes a control unit (not shown) that controls the operation of each unit. This control unit controls the irradiation path by the light beam L <b> 1 and the tool path of the cutting tool 61 based on the three-dimensional CAD data of the model 5. The irradiation path is set based on the contour shape data of each cross section obtained by slicing STL (Stereo Lithography) generated in advance from the three-dimensional CAD data of the model 5 at an equal pitch of, for example, about 0.05 mm. . The irradiation path is desirably set so that the outermost surface of the shaped article 5 has a high density with a porosity of 5% or less.

  Next, the modeling operation of the optical modeling machine 1 will be described. First, as shown in FIG. 2A, after the lifting table 32 is lowered, the powder supply plate 35 moves in the surface direction of the plate 31 to supply the powder material 2 onto the plate 31. In this way, the powder layer 21 is formed. Next, the orientation of the mirror surface of the galvanometer mirror 43 (see FIG. 1) is controlled, and as shown in FIG. 2 (b), the light beam L1 is scanned to a predetermined portion of the powder layer 21 to burn the powder material 2. As a result, the cured layer 22 is formed.

  Then, the above-described powder layer forming step shown in FIG. 2A and the cured layer forming step shown in FIG. 2B are repeated, whereby the cured layer 22 is laminated. The lamination of the hardened layer 22 is repeated until the number of layers reaches a predetermined number. When the number of hardened layers 22 reaches a predetermined number, as shown in FIG. 2C, the XY drive mechanism 63 (see FIG. 1) moves the milling head 62 and the cutting tool 61 eliminates the need for the surface of the model 5. A part is removed and the surface of the molded article 5 is made smooth. Thereafter, the modeling operation of the optical modeling machine 1 returns to the process shown in FIG. In this way, the formation of the cured layer 22 and the removal of unnecessary portions on the surface of the modeled object 5 are repeated until the modeling is completed. In the present embodiment, the cutting shown in FIG. 2C is not an essential process.

  The modeling object 5 integrally molded here is modeled so that the thermal conductivity is distributed in the interior. And in this embodiment, the hardening density in a modeled object inside is changed as a method of giving distribution to the thermal conductivity inside a modeled object. Specifically, as shown in FIG. 3, a high density portion 22 a having a high curing density or a low density portion 22 b having a low curing density is provided inside the molded article 5 (mold). “Internal” refers to the internal structure of the cured product itself formed by sintering or melting the powder layer 21, not the internal space of a mold or the like filled with resin or the like.

  The shaped article 5 formed by laminating the hardened layer 22 obtained by sintering or melting the powder layer 21 with a light beam or the like has a different curing density inside the shaped article by controlling the irradiation energy of the light beam or the like ( Structures (including unsintered or unmelted) can be shaped. For example, the hardened layer 22 sintered or melted with a high-energy light beam or the like has the constituent material sufficiently solidified, and as shown in FIG. It becomes. On the other hand, the hardened layer 22 sintered or melted with a low-energy light beam or the like does not sufficiently solidify the constituent material, and as shown in FIG. It becomes a state.

  FIG. 5 shows the relationship between cure density and thermal conductivity. The high-density portion has high thermal conductivity because the constituent materials are closely bonded. On the other hand, since the constituent material is partially separated by the pores in the low density portion, the thermal conductivity is lowered. That is, by controlling irradiation energy such as a light beam and locally changing the hardening density inside the shaped article, it is possible to have an arbitrary distribution in the thermal conductivity inside the shaped article. In addition, what has a hardening density of 50% or less is a powder state which is substantially hardly hardened | cured.

  In conventional molds using steel, etc., the thermal conductivity inside the mold is constant, so the resin temperature locally changes in the vicinity of the resin gate and at the end. This was the cause of product defects such as warping. On the other hand, as shown in FIG. 3, for example, a high-density part 22a (high thermal conductivity part) with high cooling efficiency is formed in the mold of the main structure of the model 5 and the vicinity of the resin gate 5A. By forming the low density part 22b (low thermal conductivity part) with low cooling efficiency inside the mold of the terminal part 5B, the temperature of the entire resin constituting the molded product can be made uniform. That is, according to the manufacturing method of this embodiment, the cooling temperature of the resin can be optimized by changing the curing density inside the molded article 5 (mold) to control the thermal conductivity, and the molded product. A shaped object (mold) capable of suppressing the occurrence of warpage or the like is obtained. Further, according to this method, the temperature inside the mold can be adjusted with a simple structure without providing a duct or a flow path in the mold.

  Here, the suitable formation location of the high thermal conductivity part (high density part 22a) and the low thermal conductivity part (low density part 22b) in the molded article 5 (mold) will be described with reference to FIG. For example, the gate vicinity 5A for injecting the resin into the mold is desirably a low thermal conductivity portion (low density portion 22b). Usually, the resin in this region is thin and small compared to the thickness of the molded product, so that it immediately cools and hardens. Further, when the resin is hardened in the vicinity of the gate 5A and the fluidity of the resin is lowered, it is necessary to set the injection pressure high in order to fill the resin to the mold end portion 5B. Furthermore, if the resin is hardened in the vicinity of the gate 5A, the resin does not flow in, so that unfilled resin or “sink” due to shrinkage that occurs during cooling of the molded product is likely to occur. For this reason, the temperature adjustment is desired in the vicinity of the gate 5A so that the cooling rate of the resin is slow.

  Moreover, it is desirable that the molded product design portion 5C is also a low thermal conductivity portion (low density portion 22b). When the thermal conductivity of this region is lowered, it is possible to suppress the occurrence of linear defects, that is, so-called “weld lines” that are formed in the melted and fused portions of the molten resin that has flowed in. On the front and back surfaces of the molded product, for example, if the surface side where you do not want to generate sink marks is quickly cooled and solidified, and the opposite side is reduced in thermal conductivity and cooled solidification is delayed, sink marks on the back surface side will be the slower cooling. However, sink marks on the surface side can be suppressed. On the other hand, the sprue portion 5D and the runner portion 5E are difficult to be cooled because the resin tends to be thick. Accordingly, in order to increase the cooling rate and improve the molding cycle, it is desirable that the vicinity thereof be a high thermal conductivity portion (high density portion 22a).

  The low density portion 22b described above includes a case where an unsintered portion or an unmelted portion is provided inside the molded article. In this case, the so-called low density portion 22b exists in which the powder material 2 remains in powder form. Since the material in the powder state has many gaps between the powders, as shown in FIG. 5 above, the thermal conductivity is extremely low despite being a metal. Therefore, the method of providing an unsintered part or an unmelted part inside the shaped article is suitable for molding a part in which the thermal conductivity is particularly desired to be lowered inside the mold.

  Further, when the hardened layer 5 is laminated and integrated, the cavity 23 may be provided when the hardened layer 22 (high density portion 22a) is formed. FIGS. 7A to 7D show an operation procedure for forming the cavity 23. First, after the hardened layer that forms the bottom surface of the cavity portion 23 is formed, a layer (wall surface layer) that constitutes the wall surface of the cavity portion 23 is laminated (FIG. 7A). The wall surface layer is laminated so as to protrude inward of the cavity 23 as it goes upward (FIG. 7B). The layer just before the cavity 23 is closed. It is removed by suction (FIG. 7C). Then, after removing the powder material 2, a hardened layer is formed on the upper layer so as to close the cavity 23 (FIG. 7D). The hardened layer here refers to the high density portion 22a. That is, the hollow portion 23 is a space that is surrounded by the high-density portion 22a inside the molded article.

  The step of forming these cavities 23 is preferably performed in a chamber filled with nitrogen gas, and the cavities 23 are filled with nitrogen gas. A gas such as nitrogen gas generally has a much lower thermal conductivity than a metal such as iron constituting the powder material. Therefore, when the hardened layer 5 is laminated and integrated, if the hollow portion 23 is provided, the thermal conductivity inside the molded article can be further reduced as compared with the case where an unsintered portion or an unmelted portion is provided. Note that the steps shown in FIGS. 7A to 7D are more preferably performed in a vacuum chamber. If it does so, the thermal conductivity of the said part can be made still lower.

  The cavity 23 is filled with a material having a thermal conductivity different from that of the powder material 2, that is, a high thermal conductivity material having a higher thermal conductivity than the powder material 2 or a low thermal conductivity material having a lower thermal conductivity. May be. This filling step is performed, for example, between the steps shown in FIGS. 7C and 7D described above. If it carries out like this, the heat conductivity of the said part can be arbitrarily set by selecting the material with which it fills suitably.

  Furthermore, as shown in FIG. 8, the plurality of cavities 23 may be formed in a matrix shape in the stacking direction or the planar direction. In this configuration, the high density portion 22a (high thermal conductivity portion) is formed in the cell structure, and the low density portion 22b (low thermal conductivity portion) is formed in the high density portion 22a of the cell structure. The low density portion 22b here includes a hollow portion 23 filled with an unsintered portion, an unmelted portion, and a low thermal conductivity material. Usually, the low-density portion 22b has a lower structural strength than the high-density portion 22a. Therefore, when the volume occupied by the low density portion 22b inside the modeled object increases, the strength of the modeled product itself is reduced. On the other hand, as described above, if the high-strength high-density portion 22a is formed in the cell structure and the low-density portion 22b is formed in the high-density portion 22a of the cell structure, the strength of the shaped article 5 In addition, a low thermal conductivity portion can be formed in the modeled object.

  When the high density portion 22a (high thermal conductivity portion) has a cell structure and the low density portion 22b (low thermal conductivity portion) is formed in the cell structure, as shown in FIG. 9, the low density portion 22b May be arranged so as to form a small sphere in the high-density portion 22a. In this way, since the overhang that the wall surface layer of each cell protrudes inward can be reduced, even if the low density portion 22b is in an unsintered or unmelted powder state, it is hardened that protrudes inward. Layers are not easily collapsed, and modeling can be facilitated.

  The method of forming the high density portion 22a and the low density portion 22b is not limited to appropriately controlling the irradiation energy such as the light beam as described above. Here, the modification is demonstrated with reference to Fig.10 (a)-(d). In this modification, first, the entire first hardened layer 22 on the plate 31 is formed in the high-density portion 22a (FIG. 10A). The high density portion 22a is formed by irradiating the powder layer 21 with a light beam L1 under irradiation conditions for sintering the powder material at a high density. The condensing diameter of the light beam L1 at this time is, for example, approximately 0.5 mm. Thereafter, a large number of small holes 22c are formed in a predetermined portion where the low density portion 22b is to be provided (FIG. 10B). That is, a region where a large number of small holes 22c are formed becomes the low density portion 22b. The small holes 22c are formed by the light beam L2 that increases the irradiation energy per unit area of the irradiated portion as compared with the formation of the high-density portion 22a. In order to increase the irradiation energy, for example, the focused diameter is reduced to about 0.1 mm or less, or the power is set to about 300 W or more, or the light beam is a high-energy pulsed light beam such as a Q-SW light beam. Is done.

  After the high-density part 22a and the low-density part 22b are formed in the first layer, the hardened layer 22 composed of the high-density part 22a is laminated (FIG. 10C). And the small hole 22c is formed in the hardening layer 22 according to the position of the small hole 22c of a lower layer, and the part is formed in the low density part 22b (FIG.10 (d)). The formation process of the high density part 22a and the low density part 22b mentioned above is repeated, and the molded article 5 is modeled. The small hole 22c is not formed by the light beam L1, but may be formed by opening a hole with a minute diameter drill (not shown). In this case, it is desirable that the diameter of the micro drill is 0.1 mm or less. Further, it is desirable to use a drill with a sharper tip than a drill with a small opening angle of about 120 degrees as the minute diameter drill. The micro drill is controlled by the control unit of the optical modeling machine 1. The small diameter drill may be configured in the same manner as the cutting tool 61.

  Further, the cutting removal unit 6 is preferably composed of a general-purpose numerical control (NC) machine tool including a cutting tool 61, a milling head 62, and an XY drive mechanism 63, and in particular, the cutting tool 61. It is desirable that the machining center can be automatically replaced. As the cutting tool 61, for example, a two-blade ball end mill formed of a carbide material is mainly used, and a square end mill, a radius end mill, a drill, or the like is used according to a processing shape or purpose.

  As yet another modification, the entire cured layer 22 of one layer on the plate 31 is formed as a low density portion 22b having a low cured density, and after the low density portion 22b is formed, a predetermined portion of the cured layer 22 is formed. The light beam may be re-irradiated to form the high density portion 22a having a high curing density. The irradiation conditions of the light beam at this time may be the same as or different from those at the time of forming the low density portion 22b. Further, the number of times of irradiation with the light beam L1 may be one time or a plurality of times.

  Further, a substance (not shown) that disappears upon receiving the light beam L1 is supplied only to a predetermined portion where the low density portion 22b is to be provided, and the entire powder layer 21 is irradiated with the light beam, and the substance is By eliminating the high density portion 22a and the low density portion 22b, the high density portion 22a and the low density portion 22b can be selectively formed. The substance that disappears in response to the light beam L1 is a substantially fiber-like substance such as a carbon fiber. Note that the light beam irradiation conditions may be the same as when the high-density portion 22a is formed in the above-described embodiment, for example.

  Next, the manufacturing method of the three-dimensional structure according to the second embodiment of the present invention will be described. The manufacturing method of the three-dimensional structure according to the present embodiment has a distribution in the thermal conductivity inside the three-dimensional structure by controlling the material of the powder material 2 and its blending in the above-described powder layer forming step. is there. For example, a material having a high thermal conductivity such as copper, copper alloy, aluminum, or carbon is supplied as a powder material 2 to a portion where high thermal conductivity is desired. These materials having low thermal conductivity may be used by being mixed with iron powder, which is a normal powder material for modeling, or plural kinds of materials having different thermal conductivities may be mixed. Further, a material having a low thermal conductivity such as ceramic, resin powder, epoxy resin, or the like is supplied as the powder material 2 to a portion where low thermal conductivity is desired.

  In the first embodiment described above, as the powder layer forming step, the material supply method by so-called squeezing in which the powder supply plate 35 is moved in the plane direction is shown. However, the three-dimensional structure of the present embodiment In the manufacturing method, an individual material supply mechanism capable of supplying the powder material 2 directly onto the plate 31 is provided. As this material supply mechanism, for example, a mechanism capable of attaching a cartridge (not shown) filled with the powder material 2 to the cutting removal unit 6 can be cited.

  According to the three-dimensional structure manufacturing method of the present embodiment, the thermal conductivity inside the three-dimensional structure can be distributed by a method different from the first embodiment described above. In addition, by appropriately selecting the powder material, it is possible to increase the difference in the thermal conductivity distribution inside the molded article more than the method of forming the high density portion and the low density portion.

  In the manufacturing method of the present embodiment, a low thermal conductivity portion having a low thermal conductivity is formed in the cell structure, and a high thermal conductivity portion having a high thermal conductivity is formed in the low thermal conductivity portion of the cell structure. it can. That is, in this embodiment, since both the low thermal conductivity part and the high thermal conductivity part are sufficiently solidified by sintering or melting, the heat conduction in the modeled object is not caused by reducing the strength of the modeled object. It becomes possible to have a distribution in the rate.

  Further, in the manufacturing method of the present embodiment, the powder supplied in the powder layer forming step was integrally formed by gradually increasing or decreasing the material having a low thermal conductivity from a material having a low thermal conductivity or from a material having a high thermal conductivity to a material having a low heat conductivity. It is also possible to change the thermal conductivity inside the modeled object in an inclined manner. FIGS. 11A and 11B show a configuration example of a side cross section of a model 5 (mold) formed by changing the thermal conductivity inside the model in an inclined manner. The arrows in the figure indicate the direction in which the thermal conductivity gradually increases from the low thermal conductivity region to the high thermal conductivity region. In the example of FIG. 11A, the vicinity of the molded product design portion 5C has the lowest thermal conductivity, and the thermal conductivity gradually increases radially around the periphery. Moreover, the example of FIG.11 (b) is formed so that heat conductivity may increase gradually from the upstream area into which resin etc. flow in from the upstream area.

  The interface between the high thermal conductivity portion and the low thermal conductivity portion has a large temperature difference, so that cracks due to thermal stress are likely to occur. Such cracks or the like can cause the strength of the model to be reduced. However, if the thermal conductivity inside the modeled object is changed in an inclined manner, the temperature difference at such an interface is reduced, so that the occurrence of cracks and the like can be suppressed. In addition, it is also possible to change the thermal conductivity inside the integrally formed model in an inclined manner by the manufacturing method of the first embodiment described above.

  The present invention is not limited to the manufacturing method shown in the first or second embodiment described above, and various modifications are possible. For example, the manufacturing methods shown in the first and second embodiments may be combined. That is, as a method of giving a distribution to the thermal conductivity in the modeled article, the irradiation energy of the light beam is controlled to change the curing density of the cured layer 22, and as the powder material 2 supplied to the powder layer 21, A plurality of materials having different thermal conductivities may be appropriately supplied. In addition, for example, a high density portion 22a of a cell structure is formed, and a predetermined material having a different thermal conductivity is filled in the cell so that the thermal conductivity gradually increases or decreases inside the cell structure. May be. Note that, as described above, the present invention enables the temperature adjustment of the shaped object 5 by providing a distribution of the thermal conductivity in the shaped object. For example, a cooling pipe or the like is provided in the shaped object. It may be formed, and by using these in combination, more effective temperature control can be realized.

The perspective view of the metal stereolithography processing machine used for the manufacturing method of the three-dimensional structure based on the 1st Embodiment of this invention. (A)-(c) is a partial sectional side view explaining the manufacture procedure of the molded article by the said processing machine. The sectional side view which shows an example of the three-dimensional structure molded by the said processing machine. (A) is a figure which shows the photograph of the cut surface of a high-density part, (b) is a figure which shows the photograph of the cut surface of a high-density part. The figure which shows the relationship between a cure density and heat conductivity. The sectional side view which shows the other example of the three-dimensional structure molded by the said processing machine. (A)-(d) is a sectional side view for demonstrating the process of forming a cavity part inside a three-dimensional structure. The partial cross section perspective view of the three-dimensional structure in which the high density part or the low density part was formed in the cell structure. The sectional side view of the three-dimensional structure in which the spherical low density part was formed in the high density part. (A)-(d) is a perspective view of the metal stereolithography processing machine which concerns on the 1st Embodiment of this invention. The sectional side view for demonstrating the other method of giving the literature of thermal conductivity inside a three-dimensional structure. (A) (b) is a sectional side view of the three-dimensional structure formed by the three-dimensional structure manufacturing method according to the second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal stereolithography machine 2 Powder material 21 Powder layer 22 Hardened layer 22a High-density part (high thermal conductivity part)
22b Low density part (low thermal conductivity part)
23 cavity part 3 powder layer forming part 4 hardened layer forming part 5 three-dimensional structure

Claims (10)

A powder layer forming step of supplying a powder material to form a powder layer; and a cured layer forming step of irradiating a predetermined portion of the powder layer with a light beam to sinter or melt the powder layer to form a cured layer. In the method of manufacturing a three-dimensional structure, the cured layer or the powder layer is laminated and integrated to form a three-dimensional structure.
A method for producing a three-dimensional structure, characterized in that a distribution is given to the thermal conductivity inside the integrally formed three-dimensional structure.   The method for producing a three-dimensional structure according to claim 1, wherein, in the hardened layer forming step, the distribution of the thermal conductivity inside the three-dimensional structure is controlled by controlling the curing density of the hardened layer. .   The three-dimensional according to claim 1 or 2, wherein in the hardened layer forming step, a distribution is given to the thermal conductivity inside the three-dimensional structure by providing an unsintered part or an unmelted part. Manufacturing method of a model.   The method for producing a three-dimensional structure according to any one of claims 1 to 3, wherein a distribution is given to the thermal conductivity inside the three-dimensional structure by providing a hollow portion.   The method for producing a three-dimensional structure according to claim 4, wherein the hollow portion is filled with a material having a thermal conductivity different from that of the powder material.   2. The three-dimensional structure according to claim 1, wherein, in the powder layer forming step, the distribution of the thermal conductivity inside the three-dimensional structure is controlled by controlling the material of the powder material and the blending thereof. Production method.   The high thermal conductivity portion having a high thermal conductivity is formed in the cell structure, and the low thermal conductivity portion having a low thermal conductivity is formed in the high thermal conductivity portion of the cell structure. The manufacturing method of the three-dimensional structure as described in any one of Claim 3 or Claim 6.   The low thermal conductivity portion with low thermal conductivity is formed in the cell structure, and the high thermal conductivity portion with high thermal conductivity is formed in the low thermal conductivity portion of the cell structure. The manufacturing method of the three-dimensional structure described.   The three-dimensional modeling according to any one of claims 1 to 3 or claim 6 to claim 8, wherein the thermal conductivity inside the three-dimensional modeled object that is integrally molded is changed in an inclined manner. Manufacturing method.   A three-dimensional structure manufactured by the method for manufacturing a three-dimensional structure according to any one of claims 1 to 9.

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