WO2019083042A1 - Ceramic molded object production method - Google Patents

Ceramic molded object production method

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Publication number
WO2019083042A1
WO2019083042A1 PCT/JP2018/039993 JP2018039993W WO2019083042A1 WO 2019083042 A1 WO2019083042 A1 WO 2019083042A1 JP 2018039993 W JP2018039993 W JP 2018039993W WO 2019083042 A1 WO2019083042 A1 WO 2019083042A1
Authority
WO
WIPO (PCT)
Prior art keywords
powder
laser beam
powder layer
laser
ceramic
Prior art date
Application number
PCT/JP2018/039993
Other languages
French (fr)
Japanese (ja)
Inventor
安居　伸浩
香菜子 大志万
薮田　久人
Original Assignee
キヤノン株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2018200029A external-priority patent/JP7277103B2/en
Application filed by キヤノン株式会社 filed Critical キヤノン株式会社
Priority to CN201880069808.1A priority Critical patent/CN111278618B/en
Priority to EP18870824.2A priority patent/EP3702121B1/en
Publication of WO2019083042A1 publication Critical patent/WO2019083042A1/en
Priority to US16/855,922 priority patent/US20200247005A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B28—WORKING CEMENT, CLAY, OR STONE
    • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B1/00—Producing shaped prefabricated articles from the material
    • B28B1/30—Producing shaped prefabricated articles from the material by applying the material on to a core or other moulding surface to form a layer thereon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y80/00—Products made by additive manufacturing
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64—Burning or sintering processes

Definitions

  • the present invention relates to a method for producing a ceramic shaped article, in particular, a direct shaping method using a laser beam.
  • Non-Patent Document 1 discloses that the resulting shaped object is made amorphous.
  • Non-Patent Document 2 discloses a technique for reducing the energy required for melting by lowering the melting point using a ceramic of an Al 2 O 3 -ZrO 2 eutectic composition.
  • the thermal stress is alleviated by irradiating the shaping region with auxiliary laser light while irradiating the shaping laser light while warming it to a temperature not lower than 1600 ° C. and not exceeding the melting point (preheating).
  • preheating melting point
  • There is disclosed a technique for obtaining a crystalline shaped object while avoiding rapid cooling and suppressing the occurrence of cracks since the ceramic material powder in the preheating region by the auxiliary laser light is sintered, it is difficult to obtain the shape accuracy of the surface boundary portion of the structure.
  • the present invention provides a manufacturing method for obtaining a crystalline ceramic shaped article with good shape accuracy without preheating.
  • the present invention provides a manufacturing method for obtaining a shaped product having a high crystalline ratio by avoiding a situation in which the ceramic powder is melted by laser light and then solidified when solidified. is there.
  • One aspect of the present invention is a method for producing a ceramic shaped article, (I) leveling the ceramic powder to form a powder layer; (Ii) applying a laser beam to the powder layer through a focusing optical system based on three-dimensional data to crystallize the irradiated portion; Repeatedly to produce a ceramic shaped article, In the step (ii), the laser beam is irradiated to the surface of the powder layer in an out-of-focus state.
  • the surface of the powder layer is irradiated with the laser beam in a non-focused state, so that the powder layer is melted without being subjected to high temperature preheating. It is possible to control the solidification rate from to a state in which a large amount of crystalline material is contained. This makes it possible to obtain a shaped article with high mechanical strength as compared to a shaped article containing a large amount of amorphous. Furthermore, in the heat treatment after shaping, it is possible to suppress the shrinkage deformation from amorphous to crystalline.
  • the present invention exerts an effect in the direct shaping method, so-called powder bed fusion bonding method, and the basic shaping flow will be described with reference to FIGS. 1A to 1H.
  • the powder 101 is placed on the base 130, and the powder 101 is leveled using a roller 152 to form the powder layer 102 (FIGS. 1A and 1B).
  • the surface of the powder layer 102 is irradiated with a laser beam emitted from a laser beam source 180 including a focusing optical system while being scanned by a scanner unit 181 based on 3D data of a three-dimensional model to be formed.
  • the powder melts while being irradiated with the laser beam, and the melted portion solidifies after the laser beam passes to form the object 100 (FIG. 1C).
  • stage 151 is lowered to form a new powder layer 102 on the object 100, and the laser beam is irradiated while scanning based on 3D data (FIGS. 1D and 1E). These series of steps are repeated to form a shaped object 100 having a desired shape (FIG. 1F). Finally, the non-solidified powder 103 is removed (FIG. 1G), and unnecessary portions of the shaped object 100 are removed and the shaped object 100 and the base 130 are separated as needed (FIG. 1H).
  • the first aspect of the present invention comprises (i) leveling the ceramic powder to form a powder layer, and (ii) irradiating the powder layer with a laser beam based on three-dimensional data to crystallize the irradiated portion. And producing the shaped ceramic article by repeatedly applying the laser beam to the surface of the powder layer in an unfocused state in the step (ii). It is a manufacturing method of the ceramic modeling thing made with.
  • the method for producing a shaped article according to the present invention comprises the step (i) of leveling the ceramic powder to form a powder layer.
  • the ceramic powder preferably contains a metal oxide as a main component.
  • a metal oxide as a main component of a raw material of a shaped object, a shaped object with high accuracy can be obtained without causing decomposition and gasification by irradiation with a laser beam to cause formation defects.
  • the main component of the metal which comprises the said metal oxide is aluminum. That is, a metal oxide or the like mainly containing aluminum oxide can be used.
  • Aluminum oxide is a versatile structural ceramic, and by appropriately melting and solidifying it, a shaped article having high mechanical strength can be obtained.
  • the powder in the present invention more preferably contains at least one selected from gadolinium oxide, terbium oxide and praseodymium oxide as accessory components.
  • the powder contains gadolinium oxide, and thus has a melting point lower than that of aluminum oxide alone near the Al 2 O 3 -Gd 2 O 3 eutectic composition.
  • the powder can be melted with a small amount of heat, and the diffusion of laser light in the powder is suppressed, so that the modeling accuracy is improved.
  • the shaped article has a phase separation structure composed of two or more phases. Thereby, the extension of the crack is suppressed, and the mechanical strength of the shaped article is improved.
  • gadolinium oxide When an oxide of another rare earth element (except terbium and praseodymium) is used instead of gadolinium oxide, an effect similar to that of gadolinium oxide can be obtained.
  • the powder has sufficient absorbing power to the laser light, the spread of heat in the powder is suppressed, and local melting and solidification occur, and the influence of the heat on the non-shaped part is reduced. , Modeling accuracy is improved.
  • Nd: YAG laser, terbium oxide (Tb 4 O 7 ), praseodymium oxide (Pr 6 O 11 ), etc. show good laser light absorption, so these are included in the powder as secondary components. Is more preferable.
  • Nd: YAG laser or Yb fiber laser as a laser beam of the present invention is preferable because maintenance is unnecessary and the output stability is also possible. Moreover, it is preferable that it is a laser whose wavelength is about 1 micrometer.
  • the material of the base 130 used in the present invention is appropriately selected and used from materials such as ceramics, metals, glass and the like usually used in the production of three-dimensional objects in consideration of applications of the object and production conditions. be able to.
  • the raw material containing carbons such as a resin binder
  • moisture content and heating a powder to 400 degreeC is 2% or less. More preferably, the weight loss when heated to 800 ° C. is 2% or less.
  • the method of disposing the powder 101 on the base 130 is not particularly limited.
  • the powder 101 is disposed in layers on the base 130 by a roller 152, a blade or the like.
  • the layer thickness of the powder layer 102 is preferably 5 ⁇ m or more and 100 ⁇ m or less.
  • Step (ii)> The method for producing a shaped article according to the present invention irradiates the collected laser beam on the powder layer 102 formed in the step (i) based on three-dimensional data of the three-dimensional model which is the shaped object. , And the step of crystallizing the irradiated site.
  • the present process will be described based on the preferred embodiment.
  • a predetermined region of the surface of the powder layer 102 disposed on the base 130 in step (i) is irradiated with a laser beam to melt the powder. Then coagulate.
  • the powder absorbs the laser light and is further converted to heat to melt the powder.
  • the molten powder is cooled and solidified by the heat released from the atmosphere and the adjacent peripheral portion thereof to form a cross section of the shaped article.
  • Non Patent Literatures 1 and 2 there is a problem that the shaped article is composed of an amorphous material by quenching in the process of melting and solidification without preheating.
  • crystallization can be performed without high temperature preheating.
  • a laser beam in a non-focused state, crystallization of the melted portion can be realized.
  • the in-focus and out-of-focus states will be described using the conceptual diagrams of FIGS. 3A and 3B.
  • the laser beam reaches the powder layer in a state where the energy density at the central portion of the beam is high due to an optical system (including a fiber, a condenser lens, and the like) included in the laser beam source 180.
  • Focusing refers to the state in which the laser beam is in focus on the surface of the powder layer
  • out-of-focus refers to the state in which the laser beam is not in focus.
  • defocusing means simply a state of being deviated from the focal point position specified from the focal length of the condensing optical system of the apparatus being used. It can be said that
  • the intensity distribution at the in-focus position of the laser beam 182 is a steep Gaussian distribution as shown in the upper part of FIG. 3B.
  • the intensity distribution at the out-of-focus position of the laser beam 182 is a relatively gentle intensity distribution as compared to the in-focus position, as shown in the lower part of FIG.
  • the powder layer is irradiated with a laser beam in an out-of-focus state, unlike the case of focusing, the temperature gradient of the heating part is relaxed, and therefore, quenching after laser irradiation can be avoided. Therefore, the formation of amorphous due to rapid cooling can be suppressed, and as a result, a ceramic shaped article having a high ratio of crystalline can be obtained.
  • step (i) After forming the powder layer 102 in step (i), This can be realized by changing the height of the stage 151 upward or downward by a desired amount (for example, FIG. 2A).
  • the out-of-focus state can also be realized by moving the lens of the focusing optical system included in the laser beam source 180 or inserting or removing the lens into the light path instead of the height of the stage 151. It is also possible to obtain a desired intensity distribution by shaping the cross-sectional shape of the laser beam (FIG. 2B).
  • the melting, the melting width (L) of the solidified portion, and the melting depth (D) which occur when the powder layer is irradiated with a laser beam for 1 line scan. It defines by ratio D / L.
  • this irradiation is performed under the same laser power and scanning speed as at the time of modeling.
  • D / L is preferably 1.0 or less, and more preferably 0.2 ⁇ D / L ⁇ 0.7.
  • D / L is 1.0 or less, the formation of amorphous due to rapid cooling during solidification can be suppressed.
  • the D / L can be adjusted by the power of the laser beam in the out-of-focus state and the scanning speed.
  • the laser beam is a line scan, and the surface is constituted by a plurality of adjacent linear scans.
  • the thickness of the powder layer is preferably 5 ⁇ m or more and 100 ⁇ m or less, and in view of the requirement of modeling accuracy, the line width is about 100 ⁇ m, and the average distance between adjacent lines is preferably 20 ⁇ m or more and 400 ⁇ m or less. More preferably, it is 50 micrometers or more and 200 micrometers or less.
  • the ratio of the thickness of the powder layer to the distance between the lines irradiated with the laser beam is preferably about 4 to 6.
  • a powder layer is newly placed on the shaped article obtained in step (ii) according to step (i).
  • the powder in the irradiated part is melted and solidified to form a new formed object integrated with the previously formed part.
  • ⁇ Evaluation method> In order to evaluate that a large amount of amorphous is formed at the time of focusing and a large amount of crystalline at the time of non-focusing, it is preferable to observe an actual formed object.
  • EBSD Electro Back Scatter Diffraction Patterns
  • image acquisition of an IQ map Image Quality map
  • the IQ map is a two-dimensional image obtained by digitizing the sharpness of the Kikuchi pattern obtained from the region irradiated with the electron beam. At this time, although a signal can be obtained from the crystalline region but no signal can be obtained from the amorphous region, it can be used to determine where in the shaped object is amorphous and where is crystalline.
  • the density of amorphous is usually about 20% lower than that of crystalline, and the extent to which the shaped article is relatively with respect to the theoretical density of the crystalline state of the material constituting the shaped article It can be compared by whether it is. In this case, it is preferable to verify that the porosity of the shaped article is approximately constant.
  • Example 1 This embodiment relates to the evaluation of a shaped object obtained when the focus of the laser beam is in focus or out of focus.
  • the powder was heated in an electric furnace at 400 ° C. for 12 hours, and the weight change before and after was measured.
  • the weight loss was less than 0.5% by weight
  • the weight loss was less than 1.0% by weight.
  • ProX DMP 100 (trade name) of 3D SYSTEMS, in which a 50 W fiber laser (beam diameter: 65 ⁇ m) is mounted, was used.
  • a 30 ⁇ m thick first powder layer of the material powder was formed on an alumina base using a roller (step (i)).
  • the comparative sample 1 was formed on a part of the base, and the sample 1 was placed on the same base in a non-overlapping position.
  • a 20 W laser beam is applied to a square area of 6 ⁇ 6 mm and the focusing position (in the above apparatus used in the present embodiment, the stage height is ⁇ 1.5 mm).
  • the powder layer was irradiated, melted and solidified at a speed of 100 mm / s at 100 ⁇ m pitch so as to be filled at a pitch of 100 ⁇ m.
  • the laser beam of 30 W is 140 mm / mm at the unfocused position (the stage height -5.0 mm in this embodiment) with respect to the square area of 6 x 6 mm.
  • the powder layer was irradiated at a speed of s so as to be filled at a pitch of 100 ⁇ m, melted and solidified. Also, the drawing line was made parallel to the sides of the square. Next, a powder layer with a thickness of 20 ⁇ m was newly formed by a roller so as to cover the melting / consolidating portion (step (i)).
  • the powder layer immediately above the square area of Comparative Sample 1 and Sample 1 is irradiated with a laser in the same manner as the above conditions so as to be orthogonal to the drawing line of the first layer, and the powder in the 6 ⁇ 6 mm area is melted and solidified. I did. From the second layer, the thickness of the powder layer was fixed at 20 ⁇ m.
  • the fabricated objects of Comparative Sample 1 and Sample 1 were separated from the base alumina, and were cut and polished in a vertical plane parallel to the side face when the connecting part with the base was the lower face, to obtain an observation sample .
  • the observation was performed by EBSD, and the image acquisition of IQ map was performed.
  • the IQ map is a two-dimensional image obtained by digitizing the sharpness of the Kikuchi pattern obtained from the region irradiated with the electron beam. At this time, although a signal can be obtained from the crystalline region but no signal can be obtained from the region, it can be used to determine where in the shaped object is amorphous and where is crystalline. .
  • FIG. 5A shows an IQ map of a range including the region through which the central portion of the laser beam has passed in the cross section of the comparative sample 1. Moreover, in the cross section of the sample 1, an IQ map of a range including a region through which the central portion of the laser beam has passed is FIG. 5B.
  • the portion corresponding to the central portion of the laser beam is black and is composed of amorphous.
  • FIG. 5B it was found that the portion corresponding to the central portion of the laser beam was bright and was composed of crystalline material.
  • the crystalline portion has a eutectic structure formed from the powder configuration used in this example, it looks like a pattern, but there is no problem when it is judged to be crystalline.
  • Example 2 The present embodiment relates to the case where the forming conditions are changed in the in-focus and out-of-focus states.
  • the molded article shown in Table 1 was produced.
  • the laser power was changed in order from 20 W to 30 W and 40 W so that the powder layer was melted sufficiently in response to focusing and non-focusing, and the scan speed range was adjusted so that the scan pitch could be formed at a constant value of 100 ⁇ m. Is each condition value shown in Table 1.
  • the samples formed in the in-focus state (the stage height-1.5 mm in this example) added from Example 1 are set as comparative samples 2 to 5, and further, the out-of-focus state (in this example, the stage height-5) Samples 2 to 9 were made to have a size of 0 mm and -7.0 mm. Furthermore, the theoretical density of the three- dimensional object of this example is 5.72 g / cm 3 in the case of perfect crystallinity, and six faces of each sample formed in 6 ⁇ 6 ⁇ 6 mm are polished, and the weight and volume thereof are used. The density of the sample was calculated and further divided by the above theoretical density to obtain a relative density (100 ⁇ density of sample / theoretical density).
  • Comparative Samples 1 to 5 In the order of Comparative Samples 1 to 5, the scanning speed of the laser was gradually reduced to give more heat and try to crystallize the shaped object. However, at a relative density of around 85% as a whole, the values were flat. In Comparative Sample 5, the amount of heat was too large to maintain the shape of the object, and the relative density could not be calculated. Since the density of amorphous is about 20% lower than that of crystalline, the proportion of amorphous is large, and the relative density remained at about 85% as a whole.
  • the present embodiment relates to the correlation with the shape of the melted portion (also referred to as a solidified portion) by the laser beam in each of the in-focus and out-of-focus states.
  • melting part by a laser beam here points out the cross-sectional shape of the part which the powder layer melted and solidified by irradiation of a laser beam.
  • the shape of the melted portion (solidified portion) by the laser beam at the time of focusing and non-focusing generated by one irradiation was measured. Specifically, the powder layer is irradiated for one line while scanning the laser, and the solidified portion formed by melting and solidifying the powder is cut in a plane perpendicular to the scanning direction of the laser, and the shape thereof Observed. Shape is only the first layer (thickness of 30 ⁇ m of powder layer) and shape of melted part by laser beam at ratio of width L and depth D of solidified part as it bites into base alumina plate (D / L) Was quantified.
  • the parameters were varied from a stage height of 0.0 to -7.0 mm and a laser power of 20 to 40 W.
  • the scan speeds are all 100 mm / s.
  • the results are shown in Table 2.
  • the comparative samples 1 to 5 shown in Examples 1 and 2 can be said to be shaped articles irradiated with a laser beam which realizes a value of D / L of 1.29, or shaped articles in the vicinity conditions. Therefore, it can be seen that the laser beam under the irradiation condition where the D / L value is 1.29 is a shaped object containing a large amount of amorphous.
  • the cross section when the cross section has a sharp shape, it melts sharply in the depth direction, and heat is dissipated not only downward but also in many directions, front and rear, right and left at the time of solidification, thereby promoting quenching. It is presumed that it is amorphous. Therefore, it is inferred that the same state is obtained even when D / L is in the vicinity of this value or more (1.0 or more). Therefore, it is inferred that the same state is obtained even when D / L is in the vicinity of this value or more (1.0 or more).
  • the beam height change due to defocusing is the same regardless of whether the stage height is positive (when the stage height is 0.0 mm) or negative (when the stage height is -3.0 mm) from the in-focus position. We can confirm that there is. Therefore, in the embodiment of the present invention, only the negative side was examined.
  • the D / L value is less than 0.7 at any laser power, and it melts gently in the depth direction, and the condition of quenching is It was confirmed that the crystal was relaxed and reached crystallization.
  • the powder is not melted in the depth direction, and the powder does not solidify or melt completely in a ball shape in situ It became a situation to sinter. In this case, it was found that the bonding failure with the lower layer during lamination is not preferable.
  • the laser irradiation in the non-focused state of the present invention is performed under the irradiation condition (laser power, 0.2 ⁇ D / L ⁇ 0.7). It is preferable that the scanning speed is controlled.
  • the value of this embodiment is unique to the device used for the examination, since the value of the stage height depends on the device used. What is important is to adjust the intensity distribution of the laser beam irradiated to the powder layer by shifting the focus position relative to the powder layer, and to create a situation where the desired D / L value is achieved. That is, in the apparatus to be used, how much the focal position is shifted with respect to the powder layer depends on the type of powder to be used and the specification of the apparatus to be used.
  • the direct shaping method after melting the metal oxide with laser light, it is possible to avoid the situation of becoming amorphous when solidified, and to obtain a shaped article having a high proportion of crystalline. It is possible to produce a shaped article which is dense and which has little shrinkage at the time of firing.

Abstract

A ceramic molded object production method, which produces a ceramic molded objecs by (i) a step for smoothing a ceramic powder to form a powder layer, (ii) a step for irradiating a laser beam on the powder layer on the basis of three-dimensional data to crystallize the irradiated sites, and (iii) repeatedly performing steps (i) and (ii), is characterized in that in step (ii), the laser beam is irradiated on the surface of the powder layer in an unfocused state.

Description

セラミックス造形物の製造方法Manufacturing method of ceramic shaped article
　本発明は、セラミックス造形物の製造方法、特に、レーザー光を用いる直接造形方式での製造方法に関する。 The present invention relates to a method for producing a ceramic shaped article, in particular, a direct shaping method using a laser beam.
　近年、短時間で試作品を作製したり、少数部品を製造したりする用途において、材料粉末をエネルギービームで結合させて所望の造形物、特に三次元造形物を得る直接造形方式の三次元造形物の製造方法が普及している。特に金属分野では、粉末床熔融結合法（ｐｏｗｄｅｒ　ｂｅｄ　ｆｕｓｉｏｎ）において緻密で多様性のある造形物が得られている。金属造形物の高い緻密性は、金属粉末を効果的に熔融、凝固させることによって実現される。金属分野での成功を礎にして、セラミックス材料への展開も議論され、多くの取り組みが報告されている。酸化アルミニウムや酸化ジルコニウムなどの一般的なセラミックス材料は粉末床熔融結合法によく使用されるエネルギービームであるＮｄ：ＹＡＧレーザー、ないしＹｂファイバーレーザーの光を殆ど吸収しない。このため、金属同様に熔融させるためには、より多くのエネルギーを投入する必要があるが、レーザー光が拡散して熔融が不均一となるため、必要な造形精度を得ることが難しい状況にあった。また、セラミックス材料は融点が高いため、レーザー光によって熔融した後、凝固する際に、雰囲気や隣接する周辺部によって急冷される。非特許文献１には、得られる造形物は非晶質化することが開示されている。 In recent years, in applications in which a prototype is produced in a short time or a small number of parts are produced, three-dimensional shaping by direct shaping method in which material powders are combined with an energy beam to obtain a desired shaped article, in particular a three-dimensional shaped article Manufacturing methods for objects are widespread. In the metal field in particular, compact and versatile shaped articles are obtained in powder bed fusion. The high compactness of the shaped metal object is achieved by effectively melting and solidifying the metal powder. Building on the success in the metal field, the development of ceramic materials is also discussed, and many efforts have been reported. Common ceramic materials such as aluminum oxide and zirconium oxide hardly absorb the light of Nd: YAG laser or Yb fiber laser, which is an energy beam often used in powder bed fusion bonding method. For this reason, in order to make it melt like metal, it is necessary to input more energy, but since the laser beam is diffused and the melt becomes non-uniform, it is difficult to obtain the necessary shaping accuracy. The Further, since the ceramic material has a high melting point, it is melted by laser light and then, when solidified, it is rapidly cooled by the atmosphere or the adjacent peripheral portion. Non-Patent Document 1 discloses that the resulting shaped object is made amorphous.
　一方で、非特許文献２には、Ａｌ２Ｏ３―ＺｒＯ２共晶系組成のセラミックスを用いて融点を下げることにより、熔融に必要なエネルギーを低下させる技術が開示されている。加えて、非特許文献２には、造形領域を補助レーザー光で、１６００℃以上かつ融点を超えない温度に温めながら（予備加熱）、造形用のレーザー光を照射することで、熱応力の緩和や急冷を回避し、クラック発生を抑制しつつ結晶質の造形物を得る技術が開示されている。しかしながら、補助レーザー光による予備加熱領域のセラミックス材料粉末が焼結してしまうため、構造体の表面境界部の形状精度を得ることが困難であった。 On the other hand, Non-Patent Document 2 discloses a technique for reducing the energy required for melting by lowering the melting point using a ceramic of an Al 2 O 3 -ZrO 2 eutectic composition. In addition, in Non-Patent Document 2, the thermal stress is alleviated by irradiating the shaping region with auxiliary laser light while irradiating the shaping laser light while warming it to a temperature not lower than 1600 ° C. and not exceeding the melting point (preheating). There is disclosed a technique for obtaining a crystalline shaped object while avoiding rapid cooling and suppressing the occurrence of cracks. However, since the ceramic material powder in the preheating region by the auxiliary laser light is sintered, it is difficult to obtain the shape accuracy of the surface boundary portion of the structure.
　本発明は、予備加熱なしに形状精度の良い、結晶質のセラミックス造形物を得る製造方法を提供するものである。特に、粉末床熔融結合法において、レーザー光でセラミック粉末を熔融させた後、凝固するときに非晶質となる状況を回避し、結晶質比率の高い造形物を得る製造方法を提供するものである。 The present invention provides a manufacturing method for obtaining a crystalline ceramic shaped article with good shape accuracy without preheating. In particular, in the powder bed fusion bonding method, the present invention provides a manufacturing method for obtaining a shaped product having a high crystalline ratio by avoiding a situation in which the ceramic powder is melted by laser light and then solidified when solidified. is there.
　本発明の一態様は、セラミックス造形物の製造方法であって、
　（ｉ）セラミックス粉末を均し、粉末層を形成する工程と、
　（ｉｉ）前記粉末層に対し三次元データに基づいて集光光学系を介してレーザービームを照射し、照射部位を結晶化させる工程と、
　を繰り返し行い、セラミックス造形物を製造する方法であって、
　前記（ｉｉ）の工程において、前記レーザービームを前記粉末層の表面に対し非合焦な状態で照射することを特徴とする。 One aspect of the present invention is a method for producing a ceramic shaped article,
(I) leveling the ceramic powder to form a powder layer;
(Ii) applying a laser beam to the powder layer through a focusing optical system based on three-dimensional data to crystallize the irradiated portion;
Repeatedly to produce a ceramic shaped article,
In the step (ii), the laser beam is irradiated to the surface of the powder layer in an out-of-focus state.
　本発明によれば、粉末床熔融結合法において、粉末層の表面に対してレーザービームを非合焦な状態で照射することにより、粉末層に対して高温の予備加熱を行うことなく、熔融状態からの凝固速度を、結晶質が多く含まれる状態に制御することが可能となる。これにより、非晶質が多く含まれる造形物に比べて、機械強度の高い造形物を得ることが可能となる。さらに、造形後の熱処理において、非晶質から結晶質への収縮変形を抑制することが可能となる。 According to the present invention, in the powder bed fusion bonding method, the surface of the powder layer is irradiated with the laser beam in a non-focused state, so that the powder layer is melted without being subjected to high temperature preheating. It is possible to control the solidification rate from to a state in which a large amount of crystalline material is contained. This makes it possible to obtain a shaped article with high mechanical strength as compared to a shaped article containing a large amount of amorphous. Furthermore, in the heat treatment after shaping, it is possible to suppress the shrinkage deformation from amorphous to crystalline.
本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の一実施形態を模式的に示す断面図である。It is sectional drawing which shows typically one Embodiment of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の非合焦状態の概念を示す断面図である。It is sectional drawing which shows the concept of the unfocused state of the manufacturing method of the molded article of this invention. 本発明の造形物の製造方法の非合焦状態の概念を示す断面図である。It is sectional drawing which shows the concept of the unfocused state of the manufacturing method of the molded article of this invention. 本発明のレーザービームの断面形状を説明する概念図である。It is a conceptual diagram explaining the cross-sectional shape of the laser beam of this invention. 本発明のレーザービームの断面形状を説明する概念図である。It is a conceptual diagram explaining the cross-sectional shape of the laser beam of this invention. 本発明の造形物の製造方法におけるレーザービームの照射方法の一実施形態を示す概略図である。It is the schematic which shows one Embodiment of the irradiation method of the laser beam in the manufacturing method of the molded article of this invention. 合焦、非合焦の各状態でレーザービームを照射して得られた造形物のＥＢＳＤ法におけるＩＱマップ像である。It is an IQ map image in EBSD method of a modeling thing obtained by irradiating a laser beam in each state of focusing and non-focusing. 合焦、非合焦の各状態でレーザービームを照射して得られた造形物のＥＢＳＤ法におけるＩＱマップ像である。It is an IQ map image in EBSD method of a modeling thing obtained by irradiating a laser beam in each state of focusing and non-focusing.
　以下、本発明の実施形態について図面を参照しながら説明するが、本発明は以下の具体例になんら限定されるのもではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following specific examples.
　本発明は、直接造形方式、いわゆる粉末床熔融結合法において効果を発揮するものであり、基本的な造形の流れについて図１Ａ～１Ｈを用いて説明する。 The present invention exerts an effect in the direct shaping method, so-called powder bed fusion bonding method, and the basic shaping flow will be described with reference to FIGS. 1A to 1H.
　先ず、基台１３０上に粉末１０１を載置し、ローラー１５２を用いて粉末１０１を均して、粉末層１０２を形成する（図１Ａ及び図１Ｂ）。次に、粉末層１０２の表面に、集光光学系を含むレーザービーム源１８０から射出したレーザービームを、造形対象である三次元モデルの３Ｄデータに基づいてスキャナ部１８１で走査しながら照射する。レーザービームが照射されている間に粉末が熔融し、レーザービームが通過した後に熔融部が凝固して、造形物１００が形成される（図１Ｃ）。次に、ステージ１５１を降下させ、前記造形物１００上に新たな粉末層１０２を形成し、３Ｄデータに基づいてレーザービームを走査しながら照射する(図１Ｄ及び図１Ｅ)。これら一連の工程を繰り返して行い、所望形状の造形物１００を形成する(図１Ｆ)。最後に、未凝固の粉末１０３を除去し（図１Ｇ）、必要に応じて造形物１００の不要部分の除去や、造形物１００と基台１３０との分離を行う（図１Ｈ）。 First, the powder 101 is placed on the base 130, and the powder 101 is leveled using a roller 152 to form the powder layer 102 (FIGS. 1A and 1B). Next, the surface of the powder layer 102 is irradiated with a laser beam emitted from a laser beam source 180 including a focusing optical system while being scanned by a scanner unit 181 based on 3D data of a three-dimensional model to be formed. The powder melts while being irradiated with the laser beam, and the melted portion solidifies after the laser beam passes to form the object 100 (FIG. 1C). Next, the stage 151 is lowered to form a new powder layer 102 on the object 100, and the laser beam is irradiated while scanning based on 3D data (FIGS. 1D and 1E). These series of steps are repeated to form a shaped object 100 having a desired shape (FIG. 1F). Finally, the non-solidified powder 103 is removed (FIG. 1G), and unnecessary portions of the shaped object 100 are removed and the shaped object 100 and the base 130 are separated as needed (FIG. 1H).
　本発明の第一の態様は、（ｉ）セラミックス粉末を均し、粉末層を形成する工程と、（ｉｉ）前記粉末層に対し三次元データに基づいてレーザービームを照射し、照射部位を結晶化させる工程と、を繰り返し行ってセラミックス造形物を製造する方法であって、前記（ｉｉ）の工程において、前記レーザービームを前記粉末層の表面に対し非合焦な状態で照射することを特徴とするセラミックス造形物の製造方法である。 The first aspect of the present invention comprises (i) leveling the ceramic powder to form a powder layer, and (ii) irradiating the powder layer with a laser beam based on three-dimensional data to crystallize the irradiated portion. And producing the shaped ceramic article by repeatedly applying the laser beam to the surface of the powder layer in an unfocused state in the step (ii). It is a manufacturing method of the ceramic modeling thing made with.
　以下、本発明の製造方法の各工程について説明する。
＜工程（ｉ）＞
　本発明に係る造形物の製造方法は、セラミックス粉末を均し、粉末層を形成する工程（ｉ）を有する。
　セラミックス粉末は、金属酸化物を主成分とすることが好ましい。造形物の原料の主成分として金属酸化物を用いることで、レーザービームの照射により分解、ガス化して造形不良を起こすようなことがなく、精度の良い造形物を得ることができる。
　前記金属酸化物を構成する金属の主成分はアルミニウムであることが好ましい。すなわち、酸化アルミニウムを主成分とする金属酸化物等を用いることができる。酸化アルミニウムは汎用的な構造用セラミックスであり、適切に熔融、凝固させることによって、高い機械的強度を有する造形物を得ることができる。 Hereinafter, each process of the manufacturing method of this invention is demonstrated.
<Step (i)>
The method for producing a shaped article according to the present invention comprises the step (i) of leveling the ceramic powder to form a powder layer.
The ceramic powder preferably contains a metal oxide as a main component. By using a metal oxide as a main component of a raw material of a shaped object, a shaped object with high accuracy can be obtained without causing decomposition and gasification by irradiation with a laser beam to cause formation defects.
It is preferable that the main component of the metal which comprises the said metal oxide is aluminum. That is, a metal oxide or the like mainly containing aluminum oxide can be used. Aluminum oxide is a versatile structural ceramic, and by appropriately melting and solidifying it, a shaped article having high mechanical strength can be obtained.
　本発明における粉末は、副成分として、酸化ガドリニウム、酸化テルビウムおよび酸化プラセオジムから選択される少なくとも一種を含んでいることがより好ましい。前記粉末は、酸化ガドリニウムを含むことで、Ａｌ２Ｏ３－Ｇｄ２Ｏ３共晶系組成近傍では、酸化アルミニウム単体よりも低融点となる。これによって少ない熱量で粉末の熔融が可能となり、粉末内でのレーザー光の拡散が抑制されるため、造形精度が向上する。また、酸化ガドリニウムを含むことで、造形物は２相以上からなる相分離構造となる。これにより、クラックの伸展が抑えられ、造形物の機械的強度が向上する。酸化ガドリニウムの代わりに、他の希土類元素（テルビウムやプラセオジムを除く）の酸化物を使用した場合も、酸化ガドリニウムと同じような効果が得られる。また、粉末がレーザー光に対して十分な吸収能を有していれば、粉末内における熱の広がりが抑制されて局所的に熔融、凝固し、非造形部への熱の影響が低減するため、造形精度が向上する。たとえば、Ｎｄ：ＹＡＧレーザーを使用する場合は、酸化テルビウム（Ｔｂ４Ｏ７）や酸化プラセオジム（Ｐｒ６Ｏ１１）などが良好なレーザー光の吸収を示すため、これらを副成分として粉末に含有していることがより好ましい。炭酸ガスレーザーのようにメンテナンスが必要なものではなく、本発明のレーザービームとして、Ｎｄ：ＹＡＧレーザーまたはＹｂファイバーレーザーを使用するとメンテナンス不要で出力安定性もあり、好ましい。また、波長が１μｍ近傍のレーザーであることが好ましい。 The powder in the present invention more preferably contains at least one selected from gadolinium oxide, terbium oxide and praseodymium oxide as accessory components. The powder contains gadolinium oxide, and thus has a melting point lower than that of aluminum oxide alone near the Al 2 O 3 -Gd 2 O 3 eutectic composition. As a result, the powder can be melted with a small amount of heat, and the diffusion of laser light in the powder is suppressed, so that the modeling accuracy is improved. In addition, by including gadolinium oxide, the shaped article has a phase separation structure composed of two or more phases. Thereby, the extension of the crack is suppressed, and the mechanical strength of the shaped article is improved. When an oxide of another rare earth element (except terbium and praseodymium) is used instead of gadolinium oxide, an effect similar to that of gadolinium oxide can be obtained. In addition, if the powder has sufficient absorbing power to the laser light, the spread of heat in the powder is suppressed, and local melting and solidification occur, and the influence of the heat on the non-shaped part is reduced. , Modeling accuracy is improved. For example, when using an Nd: YAG laser, terbium oxide (Tb 4 O 7 ), praseodymium oxide (Pr 6 O 11 ), etc. show good laser light absorption, so these are included in the powder as secondary components. Is more preferable. It does not require maintenance like a carbon dioxide gas laser, and use of an Nd: YAG laser or Yb fiber laser as a laser beam of the present invention is preferable because maintenance is unnecessary and the output stability is also possible. Moreover, it is preferable that it is a laser whose wavelength is about 1 micrometer.
　以上の観点から、より好適な粉末としては、Ａｌ２Ｏ３－Ｇｄ２Ｏ３、Ａｌ２Ｏ３－Ｔｂ４Ｏ７、Ａｌ２Ｏ３－Ｇｄ２Ｏ３－Ｔｂ４Ｏ７、Ａｌ２Ｏ３－Ｐｒ６Ｏ１１、Ａｌ２Ｏ３－Ｇｄ２Ｏ３－Ｐｒ６Ｏ１１等が挙げられる。 From the above viewpoints, as more preferable powders, Al 2 O 3 -Gd 2 O 3 , Al 2 O 3 -Tb 4 O 7 , Al 2 O 3 -Gd 2 O 3 -Tb 4 O 7 , Al 2 O 3 -Pr 6 O 11, Al 2 O 3 -Gd 2 O 3 -Pr 6 O 11 and the like.
　本発明で用いられる基台１３０の材料としては、三次元造形物の製造において通常用いられるセラミックス、金属、ガラス等の材料から造形物の用途や製造条件等を考慮して適宜選択し、使用することができる。 The material of the base 130 used in the present invention is appropriately selected and used from materials such as ceramics, metals, glass and the like usually used in the production of three-dimensional objects in consideration of applications of the object and production conditions. be able to.
　本発明において用いる粉末は、樹脂バインダー等の炭素を含有する素材が添加されていないことが好ましい。また、水分を除き、粉末を４００℃まで加熱したときの重量損失が２％以下であることが好ましい。より好ましくは、８００℃まで加熱したときの重量損失が２％以下であることが好ましい。 It is preferable that the raw material containing carbons, such as a resin binder, is not added to the powder used in this invention. Moreover, it is preferable that a weight loss at the time of removing water | moisture content and heating a powder to 400 degreeC is 2% or less. More preferably, the weight loss when heated to 800 ° C. is 2% or less.
　粉末１０１を基台１３０に配置する方法は特に限定されない。粉末床熔融結合法の場合は、図１Ａ及び図１Ｂに示すように、ローラー１５２やブレード等で基台１３０の上に層状に粉末１０１を配置する。粉末層１０２をより平滑に均すためには、流動性のよい粉末を用いることが好ましく、球形で５μｍ以上の粉末を多く含むことが好ましい。また、レーザービームで効果的に造形物を得るには、粉末層１０２の層厚は５μｍ以上１００μｍ以下であることが好ましい。 The method of disposing the powder 101 on the base 130 is not particularly limited. In the case of the powder bed fusion bonding method, as shown in FIGS. 1A and 1B, the powder 101 is disposed in layers on the base 130 by a roller 152, a blade or the like. In order to level the powder layer 102 more smoothly, it is preferable to use a powder having good flowability, and it is preferable to contain many powders having a spherical shape of 5 μm or more. Moreover, in order to obtain a three-dimensional object effectively by a laser beam, the layer thickness of the powder layer 102 is preferably 5 μm or more and 100 μm or less.
＜工程（ｉｉ）＞
　本発明に係る造形物の製造方法は、上記工程（ｉ）で形成した粉末層１０２に対し、造形対象物である三次元モデルの三次元データに基づいて、集光されたレーザービームを照射し、照射部位を結晶化させる工程を有する。以下、好適な実施形態に基づいて本工程を説明する。 <Step (ii)>
The method for producing a shaped article according to the present invention irradiates the collected laser beam on the powder layer 102 formed in the step (i) based on three-dimensional data of the three-dimensional model which is the shaped object. , And the step of crystallizing the irradiated site. Hereinafter, the present process will be described based on the preferred embodiment.
　粉末床熔融結合法の場合は、図１Ａ～図１Ｃに示すように、工程（ｉ）で基台１３０上に配置した粉末層１０２の表面の所定の領域にレーザービームを照射して粉末を熔融し、次いで凝固させる。粉末にレーザービームを照射すると、粉末がレーザー光を吸収し、さらに熱に変換されて粉末が熔融する。レーザービームの照射が終了すると、熔融した粉末は、雰囲気および隣接するその周辺部からの放熱により冷却されて凝固し、造形物の一断面が形成される。非特許文献１と２からの帰結として、予備加熱がない場合には熔融および凝固の過程における急冷によって、造形物は非晶質から構成されてしまうという課題がある。 In the case of the powder bed fusion bonding method, as shown in FIGS. 1A to 1C, a predetermined region of the surface of the powder layer 102 disposed on the base 130 in step (i) is irradiated with a laser beam to melt the powder. Then coagulate. When the powder is irradiated with a laser beam, the powder absorbs the laser light and is further converted to heat to melt the powder. When the irradiation of the laser beam is completed, the molten powder is cooled and solidified by the heat released from the atmosphere and the adjacent peripheral portion thereof to form a cross section of the shaped article. As a result of Non Patent Literatures 1 and 2, there is a problem that the shaped article is composed of an amorphous material by quenching in the process of melting and solidification without preheating.
　しかしながら、本工程では、高温の予備加熱なしに結晶化させることができる。特に、レーザービームを、粉末層１０２の表面に対して、非合焦の状態で照射することにより、熔融箇所の結晶化を実現することができる。合焦、非合焦の各状態を図３Ａ及び図３Ｂの概念図を用いて説明する。レーザービームはレーザービーム源１８０に含まれる光学系（ファイバーや集光レンズ等を含む）により、ビームの中央部のエネルギー密度が高い状態で粉末層に達するようになっている。合焦とは粉末層の表面にレーザービームの焦点が合っている状態を指し、非合焦とは焦点が合っていない状態を指す。但し、焦点が合っていない状態とは、粉末層の表面がレーザービームの焦点深度外に位置している状態と言い換えることもできるが、この意味に限定されるものではない。詳しくは後述するが、本発明の本質は、粉末層上で所望のレーザービームの強度プロファイルを得るために粉末層に対し焦点位置をずらしていることである。このため、本発明における非合焦とは、その目的を達成する上においては、使用している装置の集光光学系の焦点距離から特定される焦点位置から単にずれている状態を意味しているとも言える。 However, in this step, crystallization can be performed without high temperature preheating. In particular, by irradiating the surface of the powder layer 102 with a laser beam in a non-focused state, crystallization of the melted portion can be realized. The in-focus and out-of-focus states will be described using the conceptual diagrams of FIGS. 3A and 3B. The laser beam reaches the powder layer in a state where the energy density at the central portion of the beam is high due to an optical system (including a fiber, a condenser lens, and the like) included in the laser beam source 180. Focusing refers to the state in which the laser beam is in focus on the surface of the powder layer, and out-of-focus refers to the state in which the laser beam is not in focus. However, the state of being out of focus can be reworded as the state in which the surface of the powder layer is located outside the depth of focus of the laser beam, but it is not limited to this meaning. Although the details will be described later, the essence of the present invention is to shift the focal position relative to the powder layer in order to obtain the desired laser beam intensity profile on the powder layer. For this reason, in the present invention, in order to achieve the purpose, defocusing means simply a state of being deviated from the focal point position specified from the focal length of the condensing optical system of the apparatus being used. It can be said that
　なお、レーザービーム１８２の合焦位置（図３ＡのＡＡ‘断面近傍）における強度分布は、図３Ｂの上図に示される通りに急峻なガウシアン分布となっている。一方、レーザービーム１８２の非合焦位置（図３ＡのＢＢ’断面近傍）における強度分布は、図３Ｂの下図に示される通りに合焦位置に比べ相対的に緩やかな強度分布となっている。 The intensity distribution at the in-focus position of the laser beam 182 (near the cross section AA in FIG. 3A) is a steep Gaussian distribution as shown in the upper part of FIG. 3B. On the other hand, the intensity distribution at the out-of-focus position of the laser beam 182 (near the BB 'cross section in FIG. 3A) is a relatively gentle intensity distribution as compared to the in-focus position, as shown in the lower part of FIG.
　非合焦状態で粉末層にレーザービームを照射すると、合焦の場合と異なり、加熱部の温度勾配が緩和されるため、レーザー照射後の急冷を回避することができる。このため、急冷に起因する非晶質の形成を抑制することができ、その結果として結晶質の割合の高いセラミックス造形物を得ることができる。 When the powder layer is irradiated with a laser beam in an out-of-focus state, unlike the case of focusing, the temperature gradient of the heating part is relaxed, and therefore, quenching after laser irradiation can be avoided. Therefore, the formation of amorphous due to rapid cooling can be suppressed, and as a result, a ceramic shaped article having a high ratio of crystalline can be obtained.
　次に、非合焦状態でレーザービーム照射を行う方法について説明する。例えば集光光学系の合焦状態を、図１Ｂの粉末層１０２の表面に設定している装置の場合、非合焦状態にするためには工程（ｉ）で粉末層１０２を形成した後、ステージ１５１の高さを上方向または下方向に所望量変化させることで実現可能である（例えば図２Ａ）。また、ステージ１５１の高さではなく、レーザービーム源１８０に含まれる集光光学系のレンズの移動、または光路中へのレンズの挿脱により非合焦状態を実現することもできる。また、レーザービームの断面形状の整形により所望の強度分布とすることも可能である（図２Ｂ）。 Next, a method of performing laser beam irradiation in an out-of-focus state will be described. For example, in the case of an apparatus in which the focusing state of the condensing optical system is set on the surface of the powder layer 102 in FIG. 1B, after forming the powder layer 102 in step (i), This can be realized by changing the height of the stage 151 upward or downward by a desired amount (for example, FIG. 2A). In addition, the out-of-focus state can also be realized by moving the lens of the focusing optical system included in the laser beam source 180 or inserting or removing the lens into the light path instead of the height of the stage 151. It is also possible to obtain a desired intensity distribution by shaping the cross-sectional shape of the laser beam (FIG. 2B).
　本発明における非合焦状態をより詳しく定義するために、レーザービームを粉末層に１ラインスキャン照射した場合に生じる熔融、凝固部の熔融の幅（Ｌ）と、熔融の深さ（Ｄ）の比Ｄ／Ｌで定義する。なお、この照射は造形時と同じレーザーパワー、スキャン速度のもとで行われる。 In order to define the non-focused state in the present invention in more detail, the melting, the melting width (L) of the solidified portion, and the melting depth (D) which occur when the powder layer is irradiated with a laser beam for 1 line scan. It defines by ratio D / L. In addition, this irradiation is performed under the same laser power and scanning speed as at the time of modeling.
　Ｄ／Ｌは、１．０以下であることが好ましく、さらに０．２≦Ｄ／Ｌ≦０．７であることが好ましい。Ｄ／Ｌが１．０以下であることで、凝固時の急冷に起因する非晶質の形成を抑制することができる。 D / L is preferably 1.0 or less, and more preferably 0.2 ≦ D / L ≦ 0.7. When D / L is 1.0 or less, the formation of amorphous due to rapid cooling during solidification can be suppressed.
　なお、Ｄ／Ｌは、非合焦状態におけるレーザービームのパワー、スキャン速度によって調整できる。 The D / L can be adjusted by the power of the laser beam in the out-of-focus state and the scanning speed.
　因みに、本発明のレーザービーム照射による造形物の形成においては、レーザービームはラインスキャンであり、隣接する複数本のライン状のスキャンにより面を構成するものである。粉末層の厚みは、５μｍ以上１００μｍ以下であることが好ましいことと、造形精度の要請から、ライン幅を１００μｍ程度として、隣接するライン間の平均距離は２０μｍ以上４００μｍ以下であることが好ましい。より好ましくは、５０μｍ以上２００μｍ以下である。粉末層の厚みとレーザービームを照射するライン間距離の比（ライン間距離／粉末層厚さ）は、４から６程度が好適である。 Incidentally, in the formation of a shaped object by the laser beam irradiation of the present invention, the laser beam is a line scan, and the surface is constituted by a plurality of adjacent linear scans. The thickness of the powder layer is preferably 5 μm or more and 100 μm or less, and in view of the requirement of modeling accuracy, the line width is about 100 μm, and the average distance between adjacent lines is preferably 20 μm or more and 400 μm or less. More preferably, it is 50 micrometers or more and 200 micrometers or less. The ratio of the thickness of the powder layer to the distance between the lines irradiated with the laser beam (the distance between lines / the thickness of the powder layer) is preferably about 4 to 6.
＜工程（ｉ）、（ｉｉ）の繰り返し＞
　本発明に係る造形物の製造方法は、上記工程（ｉ）、（ｉｉ）の工程を繰り返し、造形物を形成する。 <Repeat of steps (i) and (ii)>
The method for producing a shaped article according to the present invention repeats the steps (i) and (ii) to form a shaped article.
　工程（ｉｉ）で得られた造形物の上に、工程（ｉ）によって新たに粉末層を配置する。配置された粉末にレーザービームを照射すると、照射部の粉末は熔融、凝固し、先に造形された部分と一体となった新たな造形物が形成される。工程（ｉ）と工程（ｉｉ）を交互に繰り返すことで所望の三次元形状を有する造形物が得られる。 A powder layer is newly placed on the shaped article obtained in step (ii) according to step (i). When the arranged powder is irradiated with a laser beam, the powder in the irradiated part is melted and solidified to form a new formed object integrated with the previously formed part. By alternately repeating step (i) and step (ii), a three-dimensional object having a desired three-dimensional shape can be obtained.
＜評価方法＞
　合焦時に非晶質が多く形成され、非合焦時に結晶質が多いことを評価するには、実際の造形物の観察を行うことが好ましい。特に、ＥＢＳＤ（Ｅｌｅｃｔｒｏｎ　Ｂａｃｋ　Ｓｃａｔｔｅｒ　Ｄｉｆｆｒａｃｔｉｏｎ　Ｐａｔｔｅｒｎｓ）法では、ＩＱマップ（Ｉｍａｇｅ　Ｑｕａｌｉｔｙ　ｍａｐ）の画像取得を行うことが好ましい。ＩＱマップとは、電子線を照射した領域から得られる菊池パターンの先鋭度を数値化し、２次元画像としたものである。このとき、結晶質の領域からはシグナルが得られるが、非晶質の領域からはシグナルが得られないため、造形物のどこが非晶質で、どこが結晶質かを判別することに利用できる。 <Evaluation method>
In order to evaluate that a large amount of amorphous is formed at the time of focusing and a large amount of crystalline at the time of non-focusing, it is preferable to observe an actual formed object. In particular, in the EBSD (Electron Back Scatter Diffraction Patterns) method, it is preferable to perform image acquisition of an IQ map (Image Quality map). The IQ map is a two-dimensional image obtained by digitizing the sharpness of the Kikuchi pattern obtained from the region irradiated with the electron beam. At this time, although a signal can be obtained from the crystalline region but no signal can be obtained from the amorphous region, it can be used to determine where in the shaped object is amorphous and where is crystalline.
　また、非晶質は結晶質に比べて、一般的に２割程度低密度であることが多く、造形物を構成する材料の結晶状態の理論密度に対して、造形物が相対的にどの程度であるかで比較することができる。この場合、造形物の空孔率がおおよそ一定の条件であるとして検証することが好ましい。 Moreover, in general, the density of amorphous is usually about 20% lower than that of crystalline, and the extent to which the shaped article is relatively with respect to the theoretical density of the crystalline state of the material constituting the shaped article It can be compared by whether it is. In this case, it is preferable to verify that the porosity of the shaped article is approximately constant.
　以下に実施例を挙げて、本発明に係る造形物の製造方法を詳細に説明するが、本発明は、以下の実施例になんら限定されるものではない。 EXAMPLES The method for producing a shaped article according to the present invention will be described in detail by way of examples, but the present invention is not limited to the following examples.
（実施例１）
　本実施例は、レーザービームの焦点が、合焦、非合焦の場合に得られる造形物の評価に関する。 Example 1
This embodiment relates to the evaluation of a shaped object obtained when the focus of the laser beam is in focus or out of focus.
＜本発明の一例であるセラミックス粉末の準備＞
　それぞれ粒子が球状のα－Ａｌ２Ｏ３粉末（平均粒径２０μｍ）、Ｇｄ２Ｏ３粉末（平均粒径２５μｍ）、Ｔｂ4Ｏ7粉末（平均粒径３μｍ）を用意し、質量比でＡｌ２Ｏ３：Ｇｄ２Ｏ３：Ｔｂ４Ｏ７＝２．１０：２．００：０．１８となるように各粉末を秤量した。各秤量粉末を乾式ボールミルで３０分間混合して混合粉末（材料粉末）を得た。 Preparation of Ceramic Powder as an Example of the Present Invention
Prepare α-Al 2 O 3 powder (average particle diameter 20 μm), Gd 2 O 3 powder (average particle diameter 25 μm), and Tb 4 O 7 powder (average particle diameter 3 μm) in which the particles are spherical, respectively. Each powder was weighed so that 2 O 3 : Gd 2 O 3 : Tb 4 O 7 = 2.10: 2.00: 0.18. Each weighed powder was mixed in a dry ball mill for 30 minutes to obtain a mixed powder (material powder).
　この混合粉末に含まれる有機成分の量を調査するために、粉末を４００℃の電気炉で１２時間加熱して、前後の重量変化を計測したところ、重量損失は０．５重量％未満であった。また、８００℃の電気炉で１２時間加熱して、前後の重量変化を計測したところ、重量損失は１．０重量％未満であった。 In order to investigate the amount of organic components contained in this mixed powder, the powder was heated in an electric furnace at 400 ° C. for 12 hours, and the weight change before and after was measured. The weight loss was less than 0.5% by weight The In addition, when heating was performed in an electric furnace at 800 ° C. for 12 hours and weight change before and after was measured, the weight loss was less than 1.0% by weight.
＜造形工程＞
　造形物の形成には、５０Ｗのファイバーレーザー（ビーム径６５μｍ）が搭載されている３Ｄ　ＳＹＳＴＥＭＳ社のＰｒｏＸ　ＤＭＰ　１００（商品名）を用いた。 <Forming process>
For the formation of a shaped object, ProX DMP 100 (trade name) of 3D SYSTEMS, in which a 50 W fiber laser (beam diameter: 65 μm) is mounted, was used.
　最初に、ローラーを用いてアルミナ製の基台上に前記材料粉末の３０μｍ厚の一層目の粉末層を形成した（工程（ｉ））。次いで、前記基台上の一部に比較サンプル１を、同一基台上の重ならない位置にサンプル１を配置するレイアウトにおいて造形を行った。比較サンプル１においては、工程（ｉｉ）として、６×６ｍｍの正方形の領域に対して２０Ｗのレーザービームを、合焦位置（本実施例で使用した上記装置においてはステージ高さ－１．５ｍｍ）において１００ｍｍ／ｓの速さで、１００μｍピッチで塗りつぶすように前記粉末層に照射し、熔融、凝固させた。一方、サンプル１では本発明の工程（ｉｉ）として、６×６ｍｍの正方形の領域に対して３０Ｗのレーザービームを非合焦位置（本実施装置においてはステージ高さ－５．０ｍｍ）において１４０ｍｍ／ｓの速さで、１００μｍピッチで塗りつぶすように前記粉末層に照射し、熔融、凝固させた。また、描画ラインは正方形の辺に平行になるようにした。次に、前記熔融・凝固部を覆うように２０μｍ厚の粉末層をローラーで新たに形成した（工程（ｉ））。一層目の描画ラインと直交するように、比較サンプル１とサンプル１の正方形の領域直上にある粉末層に、レーザーを前記条件と同様に照射し、６×６ｍｍの領域内の粉末を熔融、凝固させた。なお、２層目からは、粉末層の厚さを２０μｍで一定とした。 First, a 30 μm thick first powder layer of the material powder was formed on an alumina base using a roller (step (i)). Next, the comparative sample 1 was formed on a part of the base, and the sample 1 was placed on the same base in a non-overlapping position. In Comparative Sample 1, as the step (ii), a 20 W laser beam is applied to a square area of 6 × 6 mm and the focusing position (in the above apparatus used in the present embodiment, the stage height is −1.5 mm). The powder layer was irradiated, melted and solidified at a speed of 100 mm / s at 100 μm pitch so as to be filled at a pitch of 100 μm. On the other hand, in the sample 1, as the step (ii) of the present invention, the laser beam of 30 W is 140 mm / mm at the unfocused position (the stage height -5.0 mm in this embodiment) with respect to the square area of 6 x 6 mm. The powder layer was irradiated at a speed of s so as to be filled at a pitch of 100 μm, melted and solidified. Also, the drawing line was made parallel to the sides of the square. Next, a powder layer with a thickness of 20 μm was newly formed by a roller so as to cover the melting / consolidating portion (step (i)). The powder layer immediately above the square area of Comparative Sample 1 and Sample 1 is irradiated with a laser in the same manner as the above conditions so as to be orthogonal to the drawing line of the first layer, and the powder in the 6 × 6 mm area is melted and solidified. I did. From the second layer, the thickness of the powder layer was fixed at 20 μm.
　このような工程（ｉ）と（ｉｉ）の繰り返しにより、底面６ｍｍ×６ｍｍで高さ６ｍｍの２つの造形物を作製した。描画手順としては、図４に示すように描画し、ｎ層からｎ＋１層、ｎ＋２層、ｎ＋３層と、各層の間で、方向を９０°回転させながら造形物が所望の厚みになるまで繰り返した。図４において、鎖線で囲まれた上記正方形の領域内で、実線は実際にレーザーを照射しながら走査するラインであり、破線はレーザーを照射せずに走査するラインを示している。 By repeating such steps (i) and (ii), two shaped objects having a bottom surface of 6 mm × 6 mm and a height of 6 mm were produced. As a drawing procedure, drawing is performed as shown in FIG. 4 and repeated until the desired thickness of the object is obtained while rotating the direction 90 ° between the n layer, the n + 1 layer, the n + 2 layer, the n + 3 layer and each layer. . In FIG. 4, in the square area surrounded by a chain line, a solid line is a line which is scanned while actually irradiating a laser, and a broken line indicates a line which is scanned without irradiating a laser.
＜評価＞
　作製した比較サンプル１とサンプル１の造形物は、基台のアルミナから切り離し、基台との接続部を下面としたとき、側面に平行な鉛直面で切断、研磨を行い、観察用試料とした。観察は、ＥＢＳＤによって行い、ＩＱマップの画像取得を行った。ＩＱマップとは、電子線を照射した領域から得られる菊池パターンの先鋭度を数値化し、２次元画像としたものである。このとき、結晶質の領域からはシグナルが得られるが、領域からはシグナルが得られないため、造形物のどこが非晶質で、どこが結晶質であるかを判別することに利用することができる。 <Evaluation>
The fabricated objects of Comparative Sample 1 and Sample 1 were separated from the base alumina, and were cut and polished in a vertical plane parallel to the side face when the connecting part with the base was the lower face, to obtain an observation sample . The observation was performed by EBSD, and the image acquisition of IQ map was performed. The IQ map is a two-dimensional image obtained by digitizing the sharpness of the Kikuchi pattern obtained from the region irradiated with the electron beam. At this time, although a signal can be obtained from the crystalline region but no signal can be obtained from the region, it can be used to determine where in the shaped object is amorphous and where is crystalline. .
　比較サンプル１の断面において、レーザービームの中央部が通過していた領域を含む範囲のＩＱマップが図５Ａである。また、サンプル１の断面において、レーザービーム中央部が通過していた領域を含む範囲のＩＱマップが図５Ｂである。 FIG. 5A shows an IQ map of a range including the region through which the central portion of the laser beam has passed in the cross section of the comparative sample 1. Moreover, in the cross section of the sample 1, an IQ map of a range including a region through which the central portion of the laser beam has passed is FIG. 5B.
　ＩＱマップ図５Ａでは、レーザービームの中央部に該当する箇所が黒くなっており、非晶質から構成されることが判った。一方で、図５Ｂでは、レーザービームの中央部に該当する箇所が明るくなっており、結晶質から構成されることが判った。また、本実施例で用いた粉末構成から、結晶質部分は共晶組織が形成されているため、模様があるように見えるが、結晶質と判断して問題はない。 In the IQ map FIG. 5A, it was found that the portion corresponding to the central portion of the laser beam is black and is composed of amorphous. On the other hand, in FIG. 5B, it was found that the portion corresponding to the central portion of the laser beam was bright and was composed of crystalline material. In addition, although the crystalline portion has a eutectic structure formed from the powder configuration used in this example, it looks like a pattern, but there is no problem when it is judged to be crystalline.
　以上から、レーザービームを合焦位置で粉末層の表面に照射した場合の比較サンプル１は、非晶質領域が結晶質領域より相対的に多く含まれていた。また、レーザービームを非合焦位置で粉末層の表面に照射した場合のサンプル１は、結晶質領域が非晶質領域より相対的に多く含まれて構成されていることが明らかとなった。その結果、結晶質の造形物を得るためには、レーザービームを非合焦位置で照射することが有効であることが確認された。 From the above, in the case of Comparative Sample 1 in which the surface of the powder layer was irradiated with the laser beam at the in-focus position, the amorphous region was relatively larger than the crystalline region. In addition, it was revealed that Sample 1 in the case where the surface of the powder layer was irradiated with the laser beam at the non-focused position was configured such that the crystalline region was contained relatively more than the amorphous region. As a result, it was confirmed that it is effective to irradiate the laser beam at an out-of-focus position in order to obtain a crystalline shaped object.
（実施例２）
　本実施例は、合焦、非合焦の各状態で造形条件を変化させた場合に関する。
　実施例１の造形工程にならい、比較サンプル１、サンプル１の他に、表１に示す造形物を作製した。合焦、非合焦に対応させて粉末層が十分熔融するようにレーザーパワーを２０Ｗから３０Ｗ、４０Ｗと順に変化させ、スキャンピッチが１００μｍの一定値で造形できるよう、スキャン速度範囲を調整したのが表１に示す各条件値である。 (Example 2)
The present embodiment relates to the case where the forming conditions are changed in the in-focus and out-of-focus states.
In addition to the comparative sample 1 and the sample 1 in accordance with the molding process of Example 1, the molded article shown in Table 1 was produced. The laser power was changed in order from 20 W to 30 W and 40 W so that the powder layer was melted sufficiently in response to focusing and non-focusing, and the scan speed range was adjusted so that the scan pitch could be formed at a constant value of 100 μm. Is each condition value shown in Table 1.
　実施例１から追加した合焦状態（本実施例ではステージ高さ－１．５ｍｍ）で造形したサンプルを比較サンプル２～５とし、さらに非合焦状態（本実施例では、ステージ高さ－５．０ｍｍと－７．０ｍｍ）で造形したサンプルをサンプル２～９とした。さらに、本実施例の造形物の理論密度は完全な結晶質の場合５．７２ｇ／ｃｍ３であり、６×６×６ｍｍに造形した各サンプルの６面を研磨し、その重量と体積から各サンプルの密度を算出して、さらに上記理論密度で割ることで、相対密度（１００×サンプルの密度／理論密度）とした。 The samples formed in the in-focus state (the stage height-1.5 mm in this example) added from Example 1 are set as comparative samples 2 to 5, and further, the out-of-focus state (in this example, the stage height-5) Samples 2 to 9 were made to have a size of 0 mm and -7.0 mm. Furthermore, the theoretical density of the three- dimensional object of this example is 5.72 g / cm 3 in the case of perfect crystallinity, and six faces of each sample formed in 6 × 6 × 6 mm are polished, and the weight and volume thereof are used. The density of the sample was calculated and further divided by the above theoretical density to obtain a relative density (100 × density of sample / theoretical density).
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　比較サンプル１から５の順に、レーザーのスキャン速度を段階的に低下させ、より多い熱量を与えて造形物の結晶化を試みた。しかし、総じて８５％程度の相対密度で、値は横ばいであった。また、比較サンプル５では、熱量が多くて造形物の形が維持できず、相対密度を算出することができなかった。非晶質は結晶質よりも２割程度低密度であるため、非晶質の割合が多く、総じて８５％程度の相対密度に留まった。 In the order of Comparative Samples 1 to 5, the scanning speed of the laser was gradually reduced to give more heat and try to crystallize the shaped object. However, at a relative density of around 85% as a whole, the values were flat. In Comparative Sample 5, the amount of heat was too large to maintain the shape of the object, and the relative density could not be calculated. Since the density of amorphous is about 20% lower than that of crystalline, the proportion of amorphous is large, and the relative density remained at about 85% as a whole.
　次に、サンプル１から４の順に、レーザーのスキャン速度を段階的に低下させ、より多い熱量を与えて造形物のさらなる結晶化を試みた。サンプル１は結晶質から構成されていることが実施例１より判っているが、さらにサンプル２から４の順に相対密度の向上が見られ、結晶質の存在割合がより高まったことが判る。さらに、ステージ高さを－７．０ｍｍとしたサンプル５～９においては、同様にレーザースキャン速度を低下させると、相対密度が向上し、結晶質（相対密度９０％以上）の割合が高まることが判った。 Next, in order of samples 1 to 4, the scanning speed of the laser was gradually decreased to give more heat and try to further crystallize the shaped object. Although it is known from Example 1 that sample 1 is composed of crystalline materials, the relative density is further improved in the order of samples 2 to 4, and it can be seen that the existing ratio of crystalline materials is further enhanced. Furthermore, in Samples 5 to 9 where the stage height is -7.0 mm, the relative density is improved and the ratio of crystalline (relative density 90% or more) is increased when the laser scanning speed is similarly reduced. understood.
　以上から、合焦状態では、熱量をより多く与えても結晶化に向かうことがなく、非合焦状態では、結晶化に向かう傾向が得られ、結晶質化を促進させるためには非合焦状態での造形が必要であることが確認された。 From the above, in the in-focus state, even if a large amount of heat is given, it does not go to crystallization, and in the non-in-focus state, a tendency toward crystallization is obtained, and in order to promote crystallization It was confirmed that modeling in the state was necessary.
（実施例３）
　本実施例は、合焦、非合焦各状態のレーザービームによる熔融部（凝固部とも言い換えることができる）の形状との相関に関する。なお、ここでいうレーザービームよる熔融部の形状とは、レーザービームの照射により粉末層が熔融・凝固した部分の断面形状を指す。 (Example 3)
The present embodiment relates to the correlation with the shape of the melted portion (also referred to as a solidified portion) by the laser beam in each of the in-focus and out-of-focus states. In addition, the shape of the fusion | melting part by a laser beam here points out the cross-sectional shape of the part which the powder layer melted and solidified by irradiation of a laser beam.
　実施例１と同様の粉末を用いて、１回の照射により発生した合焦時・非合焦時のレーザービームよる熔融部（凝固部）の形状を計測した。具体的には、粉末層にレーザーを走査しながら１ライン分照射し、粉末が熔融・凝固することにより形成された凝固部を、レーザーの走査方向に対して垂直な面で切断し、その形状を観察した。造形は最初の１層（粉末層の厚み３０μｍ）のみとし、基台のアルミナ板に食い込む形で凝固した部分の幅Ｌと深さＤの比でレーザービームによる熔融部の形状（Ｄ／Ｌ）を数値化した。 Using the same powder as in Example 1, the shape of the melted portion (solidified portion) by the laser beam at the time of focusing and non-focusing generated by one irradiation was measured. Specifically, the powder layer is irradiated for one line while scanning the laser, and the solidified portion formed by melting and solidifying the powder is cut in a plane perpendicular to the scanning direction of the laser, and the shape thereof Observed. Shape is only the first layer (thickness of 30 μm of powder layer) and shape of melted part by laser beam at ratio of width L and depth D of solidified part as it bites into base alumina plate (D / L) Was quantified.
　パラメータは、ステージ高さを０．０から－７．０ｍｍ、レーザーパワーを２０から４０Ｗまで変化させた。スキャン速度はすべて１００ｍｍ／ｓである。その結果を、表２に示す。 The parameters were varied from a stage height of 0.0 to -7.0 mm and a laser power of 20 to 40 W. The scan speeds are all 100 mm / s. The results are shown in Table 2.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　この結果から熔融・凝固したときの熔融部（凝固部）の断面が最も鋭い形状（最大Ｄ／Ｌ値）を有するのが、ステージ高さ、－１．５ｍｍの時であり、この位置が合焦位置であると考える。実施例１、２で示された比較サンプル１～５は、Ｄ／Ｌが１．２９という値を実現するレーザービームによって照射された造形物、ないし近傍条件での造形物ということができる。したがって、Ｄ／Ｌ値が１．２９となる照射条件でのレーザービームでは非晶質が多く含まれた造形物となることが判る。また、この断面が鋭い形状を有している場合には、深さ方向に鋭く熔融し、凝固時に熱が下方のみならず前後左右の多方向に散逸することにより、急冷が促進される結果、非晶質化していると推察される。従って、Ｄ／Ｌがこの値近傍以上（１．０以上）でも、同様の状態になっているとものと推察される。従って、Ｄ／Ｌがこの値近傍以上（１．０以上）でも、同様の状態になっていると推察される。 From this result, it is when the stage height is -1.5 mm that the section of the melted part (solidified part) has the sharpest shape (maximum D / L value) when melted and solidified, and this position is the same position. I think it is in focus position. The comparative samples 1 to 5 shown in Examples 1 and 2 can be said to be shaped articles irradiated with a laser beam which realizes a value of D / L of 1.29, or shaped articles in the vicinity conditions. Therefore, it can be seen that the laser beam under the irradiation condition where the D / L value is 1.29 is a shaped object containing a large amount of amorphous. In addition, when the cross section has a sharp shape, it melts sharply in the depth direction, and heat is dissipated not only downward but also in many directions, front and rear, right and left at the time of solidification, thereby promoting quenching. It is presumed that it is amorphous. Therefore, it is inferred that the same state is obtained even when D / L is in the vicinity of this value or more (1.0 or more). Therefore, it is inferred that the same state is obtained even when D / L is in the vicinity of this value or more (1.0 or more).
　なお、ステージ高さは合焦位置からプラス側（ステージ高さが０．０ｍｍの時）でもマイナス側（ステージ高さが－３．０ｍｍの時）でも、非合焦化によるビームの変化は同等であることも確認できる。そのため、本発明の実施例では、マイナス側についてのみ検討した。 Note that the beam height change due to defocusing is the same regardless of whether the stage height is positive (when the stage height is 0.0 mm) or negative (when the stage height is -3.0 mm) from the in-focus position. We can confirm that there is. Therefore, in the embodiment of the present invention, only the negative side was examined.
　非合焦の－５．０ｍｍのステージ高さの場合には、いずれのレーザーパワーでもＤ／Ｌ値が０．７を下回っており、深さ方向になだらかに熔融しており、急冷の具合が緩和され、結晶化に至っていることが確認できた。ただし、ステージ高さで－６．０ｍｍの２０～２５Ｗ、－７．０ｍｍの２０～３０Ｗの領域では、深さ方向に熔融しておらず、粉末がその場でボール状に凝固ないし熔融しきらず焼結するような状況となった。この場合には、積層時に下層との接合不良となるため好ましくないことが判明した。 In the case of a non-focused -5.0 mm stage height, the D / L value is less than 0.7 at any laser power, and it melts gently in the depth direction, and the condition of quenching is It was confirmed that the crystal was relaxed and reached crystallization. However, in the region of 20 to 25 W at -6.0 mm and 20 to 30 W at -7.0 mm at the stage height, the powder is not melted in the depth direction, and the powder does not solidify or melt completely in a ball shape in situ It became a situation to sinter. In this case, it was found that the bonding failure with the lower layer during lamination is not preferable.
　以上のことから、結晶質の割合が高い造形物を得るには、本発明の非合焦状態でのレーザー照射は、０．２≦Ｄ／Ｌ≦０．７となる照射条件（レーザーパワー、スキャン速度）に制御されていることが好ましい。 From the above, in order to obtain a shaped product having a high crystalline ratio, the laser irradiation in the non-focused state of the present invention is performed under the irradiation condition (laser power, 0.2 ≦ D / L ≦ 0.7). It is preferable that the scanning speed is controlled.
　補足として、ステージ高さの値は使用する装置に依存するため、本実施例の値は検討に用いた装置固有のものである。重要なことは、粉末層に対し焦点位置を相対的にずらすことにより、粉末層に照射されるレーザービームの強度分布を調整し、所望のＤ／Ｌ値となる状況を作り出すことである。即ち、使用する装置において、粉末層に対し焦点位置をどの程度ずらすかは使用する粉末の種類、使用する装置の仕様で変わってくるものである。 As a supplement, the value of this embodiment is unique to the device used for the examination, since the value of the stage height depends on the device used. What is important is to adjust the intensity distribution of the laser beam irradiated to the powder layer by shifting the focus position relative to the powder layer, and to create a situation where the desired D / L value is achieved. That is, in the apparatus to be used, how much the focal position is shifted with respect to the powder layer depends on the type of powder to be used and the specification of the apparatus to be used.
　本発明によれば、直接造形方式において、レーザー光で金属酸化物を熔融した後、凝固させるときに非晶質となる状況を回避し、結晶質の存在比率の高い造形物を得ることができ、緻密で、かつ焼成時の収縮の少ない造形物を製造することができる。 According to the present invention, in the direct shaping method, after melting the metal oxide with laser light, it is possible to avoid the situation of becoming amorphous when solidified, and to obtain a shaped article having a high proportion of crystalline. It is possible to produce a shaped article which is dense and which has little shrinkage at the time of firing.
　本発明は上記実施の形態に制限されるものではなく、本発明の精神及び範囲から離脱することなく、様々な変更及び変形が可能である。従って、本発明の範囲を公にするために以下の請求項を添付する。 The present invention is not limited to the above embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Accordingly, the following claims are attached to disclose the scope of the present invention.
　本願は、２０１７年１０月２７日提出の日本国特許出願特願２０１７－２０８１９０、および２０１８年１０月２４日提出の日本国特許出願特願２０１８－２０００２９を基礎として優先権を主張するものであり、それらの記載内容の全てをここに援用する。 The present application claims priority based on Japanese Patent Application No. 2017-208190 filed Oct. 27, 2017 and Japanese Patent Application No. 2018-200029 filed Oct. 24, 2018. , The entire contents of those descriptions are incorporated herein.
１００　造形物
１０１　粉末
１０２　粉末層
１０３　未凝固の粉末
１３０　基台
１５１　ステージ
１５２　ローラー
１８０　レーザービーム源
１８１　スキャナ部

  DESCRIPTION OF SYMBOLS 100 Shaped object 101 Powder 102 Powder layer 103 Unconsolidated powder 130 Base 151 Stage 152 Roller 180 Laser beam source 181 Scanner part

Claims (9)

  1. 　（ｉ）セラミックス粉末を均し、粉末層を形成する工程と、
    　（ｉｉ）前記粉末層に対し三次元データに基づいてレーザービームを照射し、照射部位を結晶化させる工程と、
    　を繰り返し行い、セラミックス造形物を製造する方法であって、
    　前記（ｉｉ）の工程において、前記レーザービームは前記粉末層の表面に対し非合焦な状態で照射されることを特徴とするセラミックス造形物の製造方法。     (I) leveling the ceramic powder to form a powder layer;
    (Ii) irradiating the powder layer with a laser beam based on three-dimensional data to crystallize the irradiated site;
    Repeatedly to produce a ceramic shaped article,
    In the step (ii), the laser beam is irradiated to the surface of the powder layer in a non-focused state.
  2. 　前記（ｉｉ）の工程において、予備加熱を行わないことを特徴とする請求項１に記載のセラミックス造形物の製造方法。 In the process of said (ii), preheating is not performed, The manufacturing method of the ceramic shaped article of Claim 1 characterized by the above-mentioned.
  3. 　前記（ｉｉ）の工程において、前記照射部位の粉末層を熔融させるエネルギーを有するレーザービームを用いることを特徴とする請求項１または２に記載のセラミックス造形物の製造方法。 The method according to claim 1 or 2, wherein in the step (ii), a laser beam having energy to melt the powder layer of the irradiation site is used.
  4. 　前記粉末が金属酸化物を主成分とすることを特徴とする請求項１～３のいずれか一項に記載のセラミックス造形物の製造方法。 The method for producing a ceramic formed article according to any one of claims 1 to 3, wherein the powder contains a metal oxide as a main component.
  5. 　前記金属酸化物を構成する金属の主成分がアルミニウムであることを特徴とする請求項４に記載のセラミックス造形物の製造方法。 The method for producing a ceramic formed article according to claim 4, wherein the main component of the metal constituting the metal oxide is aluminum.
  6. 　前記粉末を８００℃まで加熱した際の重量損失が、２％以下であることを特徴とする請求項１～５のいずれか一項に記載のセラミックス造形物の製造方法。 The method for producing a ceramic formed article according to any one of claims 1 to 5, wherein a weight loss when the powder is heated to 800 ° C is 2% or less.
  7. 　前記レーザーが、Ｎｄ：ＹＡＧレーザーまたはＹｂファイバーレーザーであることを特徴とする請求項１～６のいずれか一項に記載のセラミックス造形物の製造方法。 The method for producing a ceramic formed article according to any one of claims 1 to 6, wherein the laser is an Nd: YAG laser or a Yb fiber laser.
  8. 　前記粉末層の層厚が、５μｍ以上１００μｍ以下であることを特徴とする請求項１～７のいずれか一項に記載のセラミックス造形物の製造方法。 The method for producing a ceramic formed article according to any one of claims 1 to 7, wherein the layer thickness of the powder layer is 5 μm to 100 μm.
  9. 　前記レーザー照射における１回の照射により発生する前記粉末の熔融の幅Ｌと熔融の深さＤの比であるＤ／Ｌが、０．２≦Ｄ／Ｌ≦０．７であることを特徴とする請求項１～８のいずれか一項に記載のセラミックス造形物の製造方法。

          D / L, which is the ratio of the melting width L of the powder to the melting depth D generated by one irradiation in the laser irradiation, is 0.2 ≦ D / L ≦ 0.7. A method for producing a ceramic shaped article according to any one of claims 1 to 8.

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023277052A1 (en) * 2021-06-30 2023-01-05 キヤノン株式会社 Article having silicon carbide as main component, and method for manufacturing same

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130064706A1 (en) * 2009-12-04 2013-03-14 Slm Solutions Gmbh Optical irradiation unit for a plant for producing workpieces by irradiation of powder layers with laser radiation
JP2016504215A (en) * 2012-11-30 2016-02-12 スネクマ Part manufacturing method by melting powder, powder particles reach the bath in a low temperature state
JP2016516888A (en) * 2013-02-27 2016-06-09 エスエルエム ソルーションズ グループ アーゲー Workpiece manufacturing apparatus and manufacturing method with adjusted fine structure
JP2016540109A (en) * 2013-09-23 2016-12-22 レニショウ パブリック リミテッド カンパニーＲｅｎｉｓｈａｗ Ｐｕｂｌｉｃ Ｌｉｍｉｔｅｄ Ｃｏｍｐａｎｙ Additive manufacturing apparatus and method
US20170045877A1 (en) * 2015-02-12 2017-02-16 Glowforge, Inc. Visual preview for laser fabrication
JP2017082321A (en) * 2015-07-20 2017-05-18 エスエルエム ソルーションズ グループ アーゲー Method and device for controlling irradiation system in dependence on workpiece geometry
JP2017208190A (en) 2016-05-17 2017-11-24 大日本印刷株式会社 Heating electrode device, electrically heated panel, and vehicle
JP2018200029A (en) 2017-05-29 2018-12-20 株式会社Ihi Power generation system

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130064706A1 (en) * 2009-12-04 2013-03-14 Slm Solutions Gmbh Optical irradiation unit for a plant for producing workpieces by irradiation of powder layers with laser radiation
JP2016504215A (en) * 2012-11-30 2016-02-12 スネクマ Part manufacturing method by melting powder, powder particles reach the bath in a low temperature state
JP2016516888A (en) * 2013-02-27 2016-06-09 エスエルエム ソルーションズ グループ アーゲー Workpiece manufacturing apparatus and manufacturing method with adjusted fine structure
JP2016540109A (en) * 2013-09-23 2016-12-22 レニショウ パブリック リミテッド カンパニーＲｅｎｉｓｈａｗ Ｐｕｂｌｉｃ Ｌｉｍｉｔｅｄ Ｃｏｍｐａｎｙ Additive manufacturing apparatus and method
US20170045877A1 (en) * 2015-02-12 2017-02-16 Glowforge, Inc. Visual preview for laser fabrication
JP2017082321A (en) * 2015-07-20 2017-05-18 エスエルエム ソルーションズ グループ アーゲー Method and device for controlling irradiation system in dependence on workpiece geometry
JP2017208190A (en) 2016-05-17 2017-11-24 大日本印刷株式会社 Heating electrode device, electrically heated panel, and vehicle
JP2018200029A (en) 2017-05-29 2018-12-20 株式会社Ihi Power generation system

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
FUNCTION & MATERIALS, vol. 34, September 2014 (2014-09-01), pages 12 - 17
PHYSICS PROCEDIA, vol. 5, 2010, pages 587 - 594
See also references of EP3702121A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023277052A1 (en) * 2021-06-30 2023-01-05 キヤノン株式会社 Article having silicon carbide as main component, and method for manufacturing same

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