JP2019084742A - Evaluation apparatus for raw material powder for additive manufacturing and evaluation jig therefor - Google Patents

Abstract

To provide an evaluation device for raw material powder for laminate molding, which can efficiently perform selection of raw material powder used for laminate molding, and the like.SOLUTION: An evaluation device of a present invention comprises a substantially cylindrical frame body having an annular flat upper end surface, a stage having a flat surface which is accommodated in the frame and can be lowered at least with respect to the upper end surface, a lowering means which can lower the stage with respect to the upper end surface at a predetermined interval, and a powder laying means for laying raw material powder used for laminate molding on the flat surface of the stage. Such an evaluation device is realized, for example, by incorporating an evaluation jig as described below in a molding stage of an actual laminate molding apparatus that performs powder bed fusion coupling method and the like. The evaluation jig has, for example, in addition to the frame (1) and the stage (2), a plurality of laminated shim plate (5) on which the stage is mounted, and a pull-out tool (7) capable of pulling out the shim plate one by one.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to an apparatus and the like for evaluating the suitability and the like of a raw material powder used in a layered manufacturing apparatus (so-called 3D printer).

  Recently, Additive Manufacturing (RP) (Rapid Prototyping) is frequently used to obtain a desired object by laminating a large number of cross-sectional layers in order to reduce the cost and time required to manufacture a prototype. . The additive manufacturing method starts with photofabrication using a photocurable resin, and various methods have been proposed. Among them, powder lamination molding method, in particular powder bed fusion bonding method (PBF), in which a raw material powder (especially metal powder) is solidified in order according to a desired three-dimensional shape to obtain a shaped object, is becoming mainstream at present.

  In the case of PBF, since the quality (density distribution, etc.) of recoating in which the raw material powder is laid one by one affects the quality (density distribution etc.) of the shaped object, many proposals have been made for an apparatus (simply referred to as "recoater") that performs recoating. There is a related description in the following patent documents.

WO 2015/151831

  However, before recoating, it is first important to properly select one suitable for laminate molding from a wide variety of raw material powders having different component compositions and forms (particle shape, particle size distribution, etc.). However, until now, it has been necessary to evaluate each raw material powder by carrying out a lamination molding for each raw material powder using an actual laminated molding apparatus (simply referred to as an "actual machine").

  However, in such a method, every time the raw material powder is changed, it is necessary to carefully clean the recoater and the modeling room of the actual machine to the inside, and it takes a very long time (several days) to clean it. Was. Thus, since the change (selection operation) of the raw material powder involves a large burden of man-hours, it has been practically difficult to evaluate many raw material powders.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an evaluation device and the like which can efficiently evaluate the raw material powder used for layered manufacturing.

  As a result of earnest research conducted by the present inventors to solve this problem, evaluation of the raw material powder without using a recoater and the like of a real machine (laminate modeling apparatus) which requires long cleaning work every time the raw material powder is changed. I thought of doing and completed the device that embodied this. The development of this result has led to the completion of the invention described hereinafter.

<< Evaluation system of raw material powder for layered modeling >>
(1) The evaluation device (simply referred to as "the evaluation device") of the raw material powder for laminate molding of the present invention comprises a substantially cylindrical frame having an annular flat upper end surface, and the frame body housed in the frame. A stage having a flat surface which can be lowered at least with respect to the end face, a lowering means capable of lowering the stage at a predetermined distance with respect to the upper end face, and powder on which the raw material powder used for additive manufacturing is spread on the flat surface of the stage And laying means.

(2) According to the evaluation apparatus of the present invention, the characteristics, suitability, etc. of the raw material powder for lamination modeling (simply referred to as "raw material powder" or "powder") without performing intrinsic lamination molding using a real machine Can be evaluated. For this reason, according to the evaluation device of the present invention, as in the conventional case, every time the raw material powder is changed, the powder laying device (such as recoater) or powder feeding device (feeder, powder piping, etc.) of the actual machine takes a long time There is no need to clean or to prepare a large amount of raw material powder necessary for the operation of the actual machine. Therefore, by using the evaluation apparatus of the present invention, it is possible to evaluate the suitability of various raw material powders very efficiently, and from the plural kinds of raw material powders different in component composition, particle size distribution, particle shape etc. It is possible to select a suitable raw material powder with a light burden.

<< Evaluation jig for raw material powder for layered modeling >>
(1) The present invention can be grasped not only as an evaluation device but also as an evaluation jig. That is, according to the present invention, a substantially cylindrical frame body having an annular flat upper end surface, a stage having a flat surface which is accommodated in the frame and can be lowered at least with respect to the upper end surface, and the stage is mounted It may be an evaluation jig (simply referred to as an “evaluation jig”) for the layered material powder comprising a plurality of stacked shim plates and a pull-out tool for pulling out the shim plate one by one.

(2) If the evaluation jig of the present invention is used, the above-mentioned evaluation device can be realized easily. For example, by incorporating the evaluation jig into the molding stage of the actual machine, etc., while utilizing a part of the actual machine (for example, heating means such as a laser), the powder feeder (realtor, feeder, powder piping etc.) of the actual machine It is possible to evaluate the raw material powder without using. Therefore, evaluation and selection of the raw material powder can be efficiently performed while reducing the number of operation man-hours associated with the change of the raw material powder and reducing the amount of the raw material powder used.

  In addition, although the lamination molding apparatus incorporating an evaluation jig | tool does not ask the kind, the lamination molding apparatus (especially modeling stage) which performs the powder bed fusion bonding method mentioned later or a directional energy deposition method is suitable, for example.

<< Others >>
(1) The evaluation of the raw material powder as referred to in this specification may be made based on the structure, density, etc. of the solidified body obtained after the raw material powder is irradiated with a high energy beam such as a laser and melted. It may be made based on the powdering property of the raw material powder (for example, the roughness, waviness, particle size distribution, etc. of the recoated powder surface) of the raw material powder when the spreading and the melting and solidification are repeated.

  The raw material powder referred to in the present specification may be, in addition to metal powder, compound powder such as ceramics, resin powder or the like. Further, the raw material powder is not limited to a single type powder, and may be a mixed powder in which a plurality of types of powders are mixed. In addition, according to the evaluation device of the present invention, not only the case where the same kind of raw material powder is repeatedly laminated (powdered) but also the case where different raw material iron powder is laminated can be coped with.

(2) The layered manufacturing apparatus referred to in the present specification is an apparatus that performs additive manufacturing (AM) using powder, and the apparatus that performs powder sintering lamination molding also performs powder fixed lamination molding It may be a device. According to the powder sinter layered manufacturing apparatus, the raw material powder (mainly metal powder) of each layer is sequentially irradiated with a high energy beam as a heating source to sequentially sinter the raw material powder (including melting and solidification). By doing so, a shaped object is obtained. According to the powder fixed lamination forming method, a shaped article is obtained by sequentially blowing an adhesive (ink) to the raw material powder of each layer and sequentially bonding the raw material powder.

  The powder sinter layered manufacturing apparatus may be an apparatus that performs powder bed fusion bonding (PBF) or an apparatus that performs directed energy deposition (DED). PBF scans a high energy beam (laser, electron beam, etc.) along a predetermined path every time a raw material powder (metal powder) is spread thinly, and repeatedly melting and solidifying the metal powder to form a desired shape. It is a method of obtaining a shaped article (metal bulk body). DED is a method of obtaining a shaped article (metal bulk) having a desired shape by scanning (moving) the position of melting and solidification while melting and solidifying the metal powder projected near the focal point of the high energy beam.

(3) Unless otherwise specified, "x to y" in the present specification includes the lower limit x and the upper limit y. Ranges such as “a to b” may be newly established as new lower limit values or upper limit values for arbitrary numerical values included in various numerical values or numerical ranges described in the present specification.

It is a perspective view showing an evaluation jig which is one example. It is the AA sectional view. It is a perspective view which shows the extraction tool which comprises a part of the evaluation jig. It is a schematic diagram which shows a mode that powdery raw material powder etc. are performed by the evaluation apparatus which integrated the evaluation jig | tool in the real machine.

  One or more components arbitrarily selected from the present specification may be added to the components of the present invention. The contents described in the present specification can be appropriately applied not only to the evaluation apparatus or the evaluation jig but also to an evaluation method using the same.

«Descent means»
The lowering means can lower the stage (flat surface) for evaluation by a predetermined amount. The stage may be lowered by an electric mechanism or the like, but may be adjusted by pulling out a shim plate having a predetermined thickness. For example, the lowering means preferably includes a plurality of stacked shim plates on which the stage is mounted, and a pulling means for pulling out each shim plate one by one. The drawing-out means is, for example, a separator which is interposed between adjacent shim plates to restrict movement of the shim plate in the drawing-out direction, and a drawing tool which pulls the shim plate one by one by hooking the end of the shim plate. It consists of

  In addition, it is preferable that the separator interposed between the shim plates and the shim plates adjacent to each other is, for example, housed in a stacked state in a housing portion formed below the frame housing the stage. At this time, the separator is, for example, locked in the storage portion, whereby movement (interlocking) in the pulling direction of the shim plate is restricted.

  In the evaluation apparatus of the present invention, it is sufficient to be able to evaluate the suitability and the like of the raw material powder, so it is not always necessary to repeat many operations such as lowering the stage and dusting. Therefore, it is preferable for the operator to perform these operations sequentially in order to be simple and to be easy to operate, and it is not necessary to provide a complicated mechanism and to reduce the number of cleaning man-hours and maintenance man-hours thereafter.

<< Powdering method >>
By the powder laying means, the raw material powder can be laid substantially uniformly on the stage. Apart from the recoater provided in the actual machine, a small and simple recoater dedicated to the evaluation device can also be used. However, as described above, it is preferable that the worker can easily put the powder on. Therefore, the powder laying means is preferably a spatula (blade) or a roller which moves along the upper end face of the frame. At this time, the worker may move the spatula or the roller, or the spatula or the roller may be moved along the upper end surface of the frame by an actuator including a slider or a cylinder.

<< Heating means >>
When it is necessary to melt and solidify the raw material powder (especially metal powder) laid on the stage (for example, it is necessary to evaluate the raw material powder by observing the structure of the molten solidified material obtained by PBF or DED) Case), the evaluation apparatus of the present invention is preferably provided with a heating means capable of melting the raw material powder by irradiating the raw material powder laid on the stage with a high energy beam.

  As long as the suitability of the raw material powder can be evaluated, the heating means may be a laser provided exclusively for the evaluation device, or a laser provided in an actual machine that performs PBF or DED may be used.

  The high energy beam referred to in the present specification is preferably one capable of outputting sufficient energy to melt the raw material powder, for example, a light beam (laser) or an electron beam (electron beam). Further, the heating means preferably includes a drive mechanism for relatively moving (i.e., scanning) the irradiation position of the high energy beam along a desired trajectory. The drive mechanism may move (scan) the high energy beam side using a galvano scanner or the like, or may move the stage side.

Frame and Stage
The frame accommodates the descending stage and has an annular flat upper end surface. The upper end surface is a reference surface for dusting. When the evaluation jig of the present invention is incorporated into a molding stage (casing) of an existing layered manufacturing apparatus to constitute an evaluation apparatus, the outer shape of the frame according to the present invention has a shape that can be fitted into the modeling stage of the laminated molding apparatus. Is preferable.

The upper end surface (flat surface) of the stage may be circular, oval, square or the like. In addition, as long as the size sufficient for the evaluation of the raw material powder is secured, it is preferable that the size of the stage is small in terms of cleaning performance, workability, and the like. Therefore, the area of the flat surface of the stage is preferably 200 cm ² or less, 150 cm ² or less, and more preferably 100 cm ² or less. In terms of handling and the like, the area of the flat surface of the stage is preferably 25 cm ² or more, and more preferably 50 cm ² or more.

<< Chamber >>
The evaluation of the raw material powder can be performed in the air atmosphere, but it is more preferable to be performed in the atmosphere along the modeling environment of the actual machine. Therefore, it is preferable that the evaluation device of the present invention also be provided with a chamber (case, housing) capable of controlling the atmosphere. However, when using a part of the actual machine, a chamber already installed in the actual machine may be used.

"Constitution"
The perspective view of evaluation jig S which can implement | achieve the evaluation apparatus of raw material powder is shown to FIG. 1A by integrating in the modeling stage M of a lamination-modeling apparatus (PBF). Moreover, the cross section (AA cross section) of the approximate center vicinity was shown to FIG. 1B.

  The evaluation jig S includes a frame 1 having a substantially square columnar outer shape and a cylindrical inner shape, a cylindrical stage 2 inserted into the cylindrical portion 12 of the frame 1, and a substantially square plate for supporting the frame 1 And a plurality of shim plates 5 and separators 6 alternately stacked on the base 3. As shown in FIG. The stage 2 inserted into the cylindrical portion 12 of the frame 1 is placed on the laminated shim plate 5 and separator 6.

  As shown to FIG. 1B, the separator 6 consists of a substantially square shaped thin plate which has the notch part 61 in the four corners. Each notch 61 is engaged with the support 13 at the four corners of the frame 1. Therefore, the separator 6 can move in the vertical direction, but the movement in the lateral direction is restricted.

  The shim plate 5 is formed of a rectangular thin plate, and can be inserted through the opening 14 of the frame 1 in the lateral direction. Further, at one end side of the shim plate 5, a retaining hole 51 is provided.

  Extraction of the shim plate 5 is performed using the extraction tool 7 shown in FIG. Specifically, the claw 71 of the pull-out tool 7 is hooked in the retaining hole 51 of the shim plate 5. In this state, when the puller 7 is moved in the lateral direction by holding the grip portion 72, the shim plate 5 can be pulled out.

  Adjacent shim plates 5 are separated by a separator 6 whose lateral movement is restricted. For this reason, even if one shim plate 5 is pulled out, the adjacent shim plates 5 on the lower side thereof will not be pulled out interlockingly.

  When the evaluation jig S as in this embodiment is used, for example, the work of drawing the shim plates 5 one by one can be performed efficiently and reliably even in a chamber such as a glove box.

<< Evaluation of raw material powder >>
The evaluation of the raw material powder can be performed by the following operation. First, a plurality of shim plates 5 and separators 6 are alternately stacked and disposed in an inner space formed by the frame 1 and the base 3. At this time, the shim plate 5 is adjusted in direction so that the retaining holes 51 are aligned with the opening 14 side. Further, the thickness and the number of laminated layers of the shim plate 5 and the separator 6 are such that the flat surface 21 (φ 3.5 cm / area 38.5 cm ² ) of the stage 2 is a frame when the stage 2 is placed thereon. It is adjusted in advance so as to be flush with the upper end surface 11 of the ring 1. The evaluation jig S is held by being fitted into the modeling stage M of the layered modeling apparatus. The inner space formed by the frame 1 (especially, the support 13) and the base 3 in the present embodiment corresponds to the storage in the present invention.

  Next, from the flush state between the flat surface 21 of the stage 2 and the annular upper end surface 11 of the frame 1, one shim plate 5 is drawn using the drawing tool 7. Then, a bottomed cylindrical recess c having a depth corresponding to the plate thickness (for example, 50 to 200 μm) of the shim plate 5 is formed by the cylindrical portion 12 of the frame 1 and the flat surface 21 of the stage 2 .

  Thereafter, the raw material powder p is placed on the depression c and the upper end surface 11 of the frame 1, and the spatula 8 (powder laying means) is horizontally moved in one direction along the upper end surface 11 of the frame 1. Thereby, the raw material powder p is filled in the hollow c, and the powder surface is in a leveled state.

  A laser (heating means) is irradiated (scanned) onto the raw material powder thus spread. In addition, the laser utilized what was previously provided in the real machine (PBF).

  Thereafter, the shim plate 5 is pulled out, dusted, and laser scanning is sequentially repeated. By repeating such an operation, a sample (solid body) formed by melting and solidifying the raw material powder is obtained. The suitability of the raw material powder used is evaluated by taking out the sample and observing and analyzing it.

  When another raw material powder is to be evaluated, the evaluation jig S and the periphery thereof are cleaned, and the above-described operation is repeated. Thereby, evaluation of a plurality of raw material powders can be performed efficiently with light burden.

  In addition, if evaluation jig S like a present Example is used, it can also carry out laminating | stacking alternately etc. of multiple types of raw material powder easily. When laminating a plurality of types of raw material powders, it is preferable that the powder is supplied using a rotary type feeding device capable of supplying different types of raw material powders to the upper end surface 11 of the frame 1 at predetermined rotation angles.

S Evaluation jig 1 Frame 2 Stage 3 Base 5 Shim plate 6 Separator 7 Drawer 8 Spatula p Raw material powder

Claims (10)

A substantially cylindrical frame body having an annular flat upper end surface;
A stage having a flat surface which is accommodated in the frame and can be lowered at least with respect to the upper end surface;
Lowering means capable of lowering the stage with respect to the upper end face at a predetermined interval;
Powder laying means for laying raw material powder used for additive manufacturing on the flat surface of the stage;
An evaluation device of a raw material powder for layered manufacturing comprising:   The apparatus for evaluating a material powder for layered modeling according to claim 1, wherein the powder laying means comprises a spatula or a roller moving along the upper end surface of the frame.   The evaluation device of the raw material powder for laminate modeling according to claim 2, wherein the powder laying means further includes an actuator formed of a slider or a cylinder that moves the spatula or the roller along the upper end surface of the frame. The evaluation device of a raw material powder for laminate modeling according to claim 1, wherein an area of a flat surface of the stage is 200 cm ² or less. The lowering means includes a plurality of stacked shim plates on which the stage is mounted;
Pulling out means for pulling out the shim plate one by one;
The evaluation apparatus of the raw material powder for layered modeling in any one of Claims 1-4 provided with these.   The evaluation of the raw material powder for layered formation according to claim 5, wherein the lowering means further has a separator which is interposed between the adjacent shim plates and in which movement of the shim plates in the drawing direction is restricted. apparatus.   The evaluation device for raw material powder for laminate modeling according to any one of claims 1 to 6, further comprising heating means capable of melting the raw material powder by irradiating the raw material powder laid on the stage with a high energy beam. A substantially cylindrical frame body having an annular flat upper end surface;
A stage having a flat surface which is accommodated in the frame and can be lowered at least with respect to the upper end surface;
A plurality of stacked shim plates on which the stage is mounted;
A puller for pulling out the shim plate one by one;
Evaluation jig of the raw material powder for layered modeling provided with. Furthermore, a separator interposed between adjacent ones of the shim plates;
A storage portion which accommodates the shim plate and the separator and restricts the movement of the separator in the drawing direction of the shim plate;
The evaluation jig | tool of the raw material powder for layered modeling of Claim 8 which it has.   The evaluation jig of the raw material powder for layered formation according to claim 8 or 9, which is incorporated in a shaping stage of a layered shaping apparatus for performing a powder bed fusion bonding method or a directed energy deposition method.

Images