阅读说明：本技术 3d打印方法、打印装置及存储介质 (3D printing method, printing device and storage medium ) 是由 吴俊中 蒋韦 于 2020-11-30 设计创作，主要内容包括：本申请涉及一种3D粉末成型技术领域,尤其涉及3D打印方法、打印装置及存储介质。该3D打印方法包括：在成型腔室内提供粉末材料形成粉末材料层；在粉末材料层上喷射液体组合物形成目标模型层、在至少部分粉末材料层上喷射液体组合物形成阻挡层,其中,阻挡层设置于目标模型层与成型腔室的侧壁之间；重复形成粉末材料层、目标模型层和/或阻挡层,多层目标模型层叠加形成目标模型。阻挡层削减了粉末材料与成型腔室的侧壁之间的剪切力,降低了剪切力往粉末材料层的内部区域延伸的风险,减小目标模型因受到剪切力而移位的影响,提高目标模型的打印精度以及成型腔室横截面的利用率。(The application relates to the technical field of 3D powder forming, in particular to a 3D printing method, a printing device and a storage medium. The 3D printing method comprises the following steps: providing a powder material in a forming chamber to form a layer of powder material; spraying a liquid composition on the powder material layer to form a target model layer, and spraying a liquid composition on at least part of the powder material layer to form a barrier layer, wherein the barrier layer is arranged between the target model layer and the side wall of the forming chamber; and repeatedly forming the powder material layer, the target model layer and/or the barrier layer, and laminating multiple target models to form the target model. The barrier layer reduces shearing force between the powder material and the side wall of the forming cavity, reduces the risk that the shearing force extends to the inner area of the powder material layer, reduces the influence of displacement of the target model due to the shearing force, and improves the printing precision of the target model and the utilization rate of the cross section of the forming cavity.)

1. A3D printing method, characterized in that the 3D printing method comprises:

providing a powder material in a forming chamber (61) to form a layer of powder material (1);

-spraying a liquid composition on a layer of powder material (1) to form a target molding layer (2), -spraying a liquid composition on at least part of the layer of powder material (1) to form a barrier layer (3), wherein the barrier layer (3) is arranged between the target molding layer (2) and a sidewall (611) of the forming chamber (61);

and repeatedly forming the powder material layer (1), the target model layer (2) and/or the barrier layer (3), and forming a target model by overlapping a plurality of target model layers (2).

2. The 3D printing method according to claim 1, wherein spraying the liquid composition on the layer of powder material (1) forms the target model layer (2), and wherein spraying the liquid composition on at least part of the layer of powder material (1) forms the barrier layer (3), the 3D printing method in particular comprises: -spraying said liquid composition on said layer of powder material (1) to form a target mould area, -spraying said liquid composition on at least part of said layer of powder material (1) to form a barrier area;

-providing energy to the layer of powder material (1), causing the target mould region to form the target mould layer (2), and causing the barrier region to form the barrier layer (3).

3. The 3D printing method according to claim 2, wherein the energy is selected from at least one of radiation energy and thermal energy.

4. 3D printing method according to claim 1, characterized in that at least part of the barrier layer (3) is spaced apart in the stacking direction.

5. The 3D printing method according to claim 4, characterized in that the maximum distance in the stacking direction of adjacent barrier layers (3) is an integer multiple of the layer thickness of the powder material layer (1).

6. The 3D printing method according to claim 4, wherein the minimum distance in the stacking direction of adjacent barrier layers (3) is greater than or equal to zero.

7. 3D printing method according to claim 1, characterized in that adjacent barrier layers (3) are offset in a direction perpendicular to the stacking direction.

8. The 3D printing method according to claim 7, wherein a minimum distance between adjacent barrier layers (3) in a direction perpendicular to the stacking direction is greater than or equal to zero.

9. The 3D printing method according to any of claims 1 to 8, wherein the barrier layer (3) is located at an edge position of the layer of powder material (1).

10. The 3D printing method according to any of claims 1-8, wherein an amount of the liquid composition per unit area of the barrier region is greater than an amount of the liquid composition per unit area of the target model region.

11. The 3D printing method according to any of claims 1 to 8, wherein the barrier layer (3) is of a polygonal structure.

12. The 3D printing method according to claim 11, wherein a side length of the polygonal structure is a saw-toothed structure.

13. The 3D printing method according to claim 11, wherein the barrier layer is a mesh structure.

14. The 3D printing method according to claim 13, wherein the mesh structure is a triangular structure.

15. The 3D printing method according to any of claims 1 to 8, wherein spraying the liquid composition on the layer of powder material (1) forms a bedding layer (4) before spraying the liquid composition on the layer of powder material (1) forms the target model area.

16. The 3D printing method according to claim 15, wherein the flooring layer (4) is in contact with the barrier layer (3).

17. The 3D printing method according to claim 15, wherein the flooring layer (4) comprises a mesh structure and is provided with a plurality of layers;

the density of the lattice structure of the sub-layer (4) is gradually reduced along the stacking direction.

18. The 3D printing method according to claim 17, characterized in that the amount of the liquid composition per unit area of the bottom layer (4) is greater than the amount of the liquid composition per unit area of the top layer of the bottom layer (4) when printing the bottom layer (4).

19. The 3D printing method according to any of claims 1 to 8, wherein spraying the liquid composition on the layer of powder material (1) forms a draw (5), both ends of the draw (5) being connected to the target mold layer (2) and the barrier layer (3).

20. The 3D printing method according to claim 19, wherein the tractor (5) is a mesh structure.

21. The 3D printing method according to any of claims 1 to 8, wherein the liquid composition is selected from at least one of a photo-curable material and a thermo-curable material.

22. The 3D printing method according to any of claims 1-8, wherein the liquid composition at least partially dissolves powder materials, the liquid composition comprising one or more of a solvent, an auxiliary agent, an energy absorber material.

23. The 3D printing method according to any of claims 1 to 8, wherein the 3D printing method further comprises, before spraying the liquid composition on the layer of powder material (1), preheating the layer of powder material (1).

24. A printing device (6), characterized in that the printing device (6) is configured to perform the 3D printing method according to any one of claims 1 to 23, the printing device (6) comprising:

a powder supply member (62) for supplying a powder material to form a powder material layer (1);

a forming chamber (61), said forming chamber (61) being provided with a side wall (611) and a platform (612), said platform (612) being intended to carry said layer of powder material (1);

a liquid dispenser (63) for spraying a liquid composition on the layer of powder material (1) to form a target model layer (2) and/or a barrier layer (3);

wherein the barrier layer (3) is located between the target model layer (2) and the sidewall (611).

25. The printing device (6) according to claim 24, wherein the printing device (6) further comprises a controller (64), the controller (64) being configured to control the liquid dispenser (63) to spray the liquid composition on the layer of powder material (1) to form the target model layer (2) and to control the liquid dispenser (63) to spray the liquid composition on at least part of the layer of powder material (1) to form the barrier layer (3).

26. The printing device (6) according to claim 24, wherein the printing device (6) further comprises an energy generator (65) for providing energy to the layer of powder material (1) such that the liquid composition sprayed on the layer of powder material (1) forms the target model layer (2) and/or the barrier layer (3).

27. Printing device (6) according to claim 24, wherein the printing device (6) further comprises heating means (67) for preheating the layer of powder material (1).

28. Printing device (6) according to claim 27, wherein the heating means (67) comprises at least one of a heating lamp, a heating plate, a heating sheet, a heating wire.

29. The printing device (6) according to claim 24, wherein the printing device (6) further comprises a first lifting mechanism (66) and a second lifting mechanism (68), the first lifting mechanism (66) can drive the platform (612) to descend or ascend, and the second lifting mechanism (68) can drive the powder supply component (62) to ascend or descend.

30. Printing device (6) according to claim 26, wherein the energy generator (65) comprises at least one of a UV-LED lamp, an infrared radiation lamp, a laser.

31. A storage medium characterized in that it stores instructions for controlling the execution of a 3D printing method according to any one of claims 24 to 30 of a printing apparatus (6).

Technical Field

The application relates to the technical field of 3D powder forming, in particular to a 3D printing method, a printing device and a storage medium.

Background

In the existing 3D powder molding technology, the molding device includes: the powder feeding device comprises a powder feeding cylinder, a powder spreading stick, a forming cavity and a lifting component, wherein the forming cavity comprises a side wall and a supporting plate, in the 3D printing process, the powder spreading stick pushes powder materials from the powder feeding cylinder to the supporting plate of the forming cavity to form a powder material layer with a certain thickness, and then a laser or ink-jet printing head is used for irradiating or jetting ink in a printing area according to layer printing data so as to form a layer of a target model; and then the lifting part drives the supporting plate to move downwards relative to the side wall of the forming cavity by a certain distance of the thickness of the powder material layer, the powder paving roller carries out the powder paving action of the next period, the layer forming step of the target model is repeated, and the target model is finally manufactured. Because the powder material on the supporting plate has certain mobility, in the process that the lifting component drives the supporting plate to descend, shearing force is formed between the powder material on the periphery above the supporting plate and the side wall due to friction, flatness of the side wall or verticality of the side wall and the like, so that the powder material has certain transverse movement on the supporting plate, the shearing force is gradually increased along with increase of a target model in a forming cavity, and finally the increased shearing force causes deviation of the forming position of the target model, so that the formation of a subsequent layer deviates relative to a previous layer, the accuracy of the formed target model is reduced, and even printing needs to be carried out again.

In the prior art, in order to prevent the forming position of the target model from being shifted due to shearing force, the distance between the contour of the target model and the side wall is usually larger, however, the method reduces the utilization rate of the cross section of the forming chamber, the forming chamber with larger cross section is needed when the target model with the same size is printed, the volume of the printing device is increased, and the manufacturing cost of the printing device is increased.

Disclosure of Invention

The application provides a 3D printing method, a printing device and a storage medium, aiming at reducing the risk of target model deviation caused by shearing force and improving the printing precision of a target model and the utilization rate of the cross section of a forming cavity.

The application provides a 3D printing method in a first aspect, and the 3D printing method comprises the following steps:

providing a powder material in a forming chamber to form a layer of powder material;

spraying a liquid composition on a layer of powder material to form a target molding layer, spraying a liquid composition on at least a portion of the layer of powder material to form a barrier layer, wherein the barrier layer is disposed between the target molding layer and a sidewall of the molding chamber;

and repeatedly forming the powder material layer, the target model layer and/or the barrier layer, and forming a target model by overlapping a plurality of target model layers.

In one possible design, when the liquid composition is ejected on the powder material layer to form the target model layer and the liquid composition is ejected on at least a part of the powder material layer to form the barrier layer, the 3D printing method specifically includes: spraying the liquid composition on the layer of powder material to form a target mold region, spraying the liquid composition on at least a portion of the layer of powder material to form a barrier region;

providing energy to the layer of powder material, causing the target mold region to form the target mold layer, and causing the barrier region to form the barrier layer.

In one possible design, the energy is selected from at least one of radiant energy and thermal energy.

In one possible design, at least some of the barrier layers are spaced apart in the stacking direction.

In one possible design, the maximum distance between adjacent barrier layers in the stacking direction is an integer multiple of the layer thickness of the powder material layer.

In one possible design, the minimum distance between adjacent barrier layers in the stacking direction is greater than or equal to zero.

In one possible design, adjacent barrier layers are offset in a direction perpendicular to the stacking direction.

In one possible design, the minimum distance between adjacent barrier layers in a direction perpendicular to the stacking direction is greater than or equal to zero.

In one possible design, the barrier layer is located at an edge position of the layer of powder material.

In one possible design, the amount of the liquid composition per unit area of the barrier region is greater than the amount of the liquid composition per unit area of the target model region.

In one possible design, the barrier layer is a polygonal structure.

In one possible embodiment, the sides of the polygonal structure are of a sawtooth-like structure.

In one possible design, the barrier layer is a mesh structure.

In one possible design, the mesh structure is a triangular structure.

In one possible design, the liquid composition is sprayed on the layer of powder material to form a bedding layer before the liquid composition is sprayed on the layer of powder material to form the target model area.

In one possible design, the bedding layer is in contact with the barrier layer.

In one possible design, the flooring layer comprises a grid structure and is provided with a plurality of layers;

the density of the lattice structure of the bedding layer is gradually reduced along the stacking direction.

In one possible design, the amount of the liquid composition in the unit area of the bottom layer located at the bottom is greater than the amount of the liquid composition in the unit area of the bottom layer located at the top layer when the bottom layer is printed.

In one possible design, the liquid composition is sprayed on the layer of powder material to form a draw, the two ends of which are connected to the target model layer and the barrier layer.

In one possible design, the traction part is a grid structure.

In one possible design, the liquid composition is selected from at least one of a photo-curable material and a thermally curable material.

In one possible design, the liquid composition at least partially dissolves the powder material, the liquid composition including one or more of a solvent, an adjuvant, an energy absorber material.

In one possible design, the 3D printing method further includes, before spraying the liquid composition on the layer of powder material, preheating the layer of powder material.

A second aspect of the present application provides a printing apparatus for executing the printing method of any one of the above, the printing apparatus comprising:

a powder supply part for supplying a powder material to form a powder material layer;

the forming chamber is provided with a side wall and a platform, and the platform is used for bearing the powder material layer;

a liquid dispenser for spraying a liquid composition on the layer of powder material to form a target model layer and/or barrier layer;

wherein the barrier layer is located between the target model layer and the sidewall.

In one possible design, the printing device further includes a controller for controlling the liquid dispenser to spray the liquid composition on the layer of powder material to form the target model layer and for controlling the liquid dispenser to spray the liquid composition on at least a portion of the layer of powder material to form the barrier layer.

In one possible design, the printing device further includes an energy generator for providing energy to the powder material layer such that the liquid composition sprayed on the powder material layer forms the target mold layer and/or the barrier layer.

In one possible design, the printing device further comprises a heating element for preheating the layer of powder material.

In one possible design, the heating component includes at least one of a heating lamp, a heating plate, a heating sheet, and a heating wire.

In one possible design, the printing device further includes a first lifting mechanism and a second lifting mechanism, the first lifting mechanism can drive the platform to descend or ascend, and the second lifting mechanism can drive the powder supply component to ascend or descend.

In one possible design, the energy generator comprises at least one of a UV-LED lamp, an infrared radiation lamp, a laser.

A third aspect of the present application provides a storage medium storing instructions for controlling the printing apparatus to execute any one of the 3D printing methods described above.

The technical scheme provided by the application can achieve the following beneficial effects.

The application provides a 3D printing method, a printing device and a storage medium, in the process of forming a target model, a liquid composition is sprayed on at least part of a non-target model layer of a part of a powder material layer to form a barrier layer, the barrier layer divides the powder material in a forming cavity into a plurality of sections in the laminating direction, so that the shearing force between the powder material and a side wall in the forming cavity is reduced, the risk that the shearing force extends to the inner area of the powder material layer is reduced, the influence of displacement of the target model caused by the shearing force is reduced, and the printing precision of the target model and the utilization rate of the cross section of the forming cavity are improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

FIG. 1 is a schematic cross-sectional view of a target model printing process in an embodiment of the present application;

FIG. 2 is a schematic cross-sectional view of a target model printing process in yet another embodiment of the present application;

FIG. 3 is a schematic structural diagram of a target model in the stacking direction during printing according to an embodiment of the present disclosure;

FIG. 4 is a schematic view of the structure of a target model in the stacking direction during printing according to another embodiment of the present application;

FIG. 5 is a schematic view of the structure of a target model in the stacking direction during printing according to another embodiment of the present application;

FIG. 6 is a schematic view of the structure of a target model in the stacking direction during printing according to another embodiment of the present application;

FIG. 7 is a schematic view of the structure of a target model in the stacking direction during printing according to another embodiment of the present application;

FIG. 8 is a schematic cross-sectional view of a bedding layer in a 3D printing method provided in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a bottom layer in a stacking direction in the 3D printing method provided in the embodiment of the present application;

fig. 10 is a schematic structural diagram of a printing apparatus provided in an embodiment of the present application.

Reference numerals:

1-a layer of powder material;

2-target model layer;

3-a barrier layer;

4, paving a bottom layer;

5-a traction part;

6-a printing device;

61-a shaping chamber;

611-side walls;

612-a platform;

62-a powder supply member;

621-powder storage cavity;

622-powder spreader;

623-a support plate;

63-a liquid dispenser;

64-a controller;

65-an energy generator;

66-a first lifting mechanism;

67-a heating means;

68-a second lifting mechanism.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

Detailed Description

For better understanding of the technical solutions of the present application, the following detailed descriptions of the embodiments of the present application are provided with reference to the accompanying drawings.

It should be understood that the embodiments described are only a few embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the examples of this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It should be noted that the terms "upper", "lower", "left", "right", and the like used in the embodiments of the present application are described in terms of the angles shown in the drawings, and should not be construed as limiting the embodiments of the present application. In addition, in this context, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on "or" under "the other element or be indirectly on" or "under" the other element via an intermediate element.

As shown in fig. 1 to 7, the present embodiment provides a 3D printing method, the 3D printing method including: providing a powder material in the forming chamber 61 to form a powder material layer 1; spraying a liquid composition on the powder material layer 1 to form a target model layer 2, and spraying a liquid composition on at least a part of the powder material layer 1 to form a barrier layer 3, wherein the barrier layer 3 is disposed between the target model layer 2 and a sidewall 611 of the molding chamber 61; the powder material layer 1, the target model layer 2 and/or the barrier layer 3 are repeatedly formed, and the target model is formed by overlapping a plurality of target model layers 2.

In the present embodiment, during the molding of the target model, the barrier layer 3 is formed by spraying the liquid composition onto at least a part of the powder material layer 1, and the barrier layer 3 divides the powder material in the molding chamber 61 into a plurality of segments in the stacking direction, thereby reducing the shearing force between the powder material in the molding chamber 61 and the side wall 611, reducing the risk of the shearing force extending toward the inner region of the powder material layer 1, reducing the influence of the displacement of the target model due to the shearing force, and improving the printing accuracy of the target object.

When the powder material layer 1 is formed by providing the powder material, the powder material may be preheated by the heating member 67 to increase the temperature of the powder material, so as to reinforce the strength of the target model.

The powder material may be one or more of a polymer powder material, a ceramic material, a metal powder material, a glass powder material, and the like. Specifically, the polymer powder material may be at least one of Polystyrene (PS), polyvinyl chloride (PVC), polyacrylonitrile, acrylonitrile-styrene-acrylate copolymer (ASA), Polyamide (PA), polyester, Polyurethane (PU), poly (meth) acrylate, polyvinyl fluoride, chlorinated polyolefin, polyvinyl alcohol (PVA) containing hydroxyl groups, cellulose, modified cellulose.

Taking the polymer powder material as an example, the melting point or melting temperature of the powder material in this embodiment may be 60 ℃ to 300 ℃. The particle shape and particle size of the powder material are not particularly limited. In the powder material provided by the embodiment, when the powder material layer 1 is formed, the flow property of the powder material can meet the use requirement, and the gap formed between the powder materials can be filled with the sprayed liquid composition.

The powder material in this embodiment may be in the shape of sphere, dendrite, flake, disk, needle, rod, etc. according to the difference in the process of manufacturing the powder material. The powder material has an average particle diameter of 1 to 400 μm, preferably 30 to 200 μm. The particle spacing in the powder material is approximately 5nm to 100 μm, and is not limited thereto. The particle spacing of the powder material in this example is in the range of 5nm to 100 μm, and when the liquid composition is selectively applied to the powder material layer 1, the liquid composition can rapidly penetrate into the inside of the powder material layer 1 through the spacing and remain partially on the surface layer, thereby wetting the surface of the powder material in the selected region.

The thickness of the powder material layer 1 is 10 μm to 500. mu.m, preferably 50 μm to 150. mu.m. It is understood that when the thickness of the powder material layer 1 is thin, a target pattern with high resolution can be formed, but the time taken to manufacture the target pattern is greatly lengthened, and the manufacturing cost is increased; when the thickness of the powder material layer 1 is thick, the time for the liquid composition to infiltrate the powder material is lengthened, and the resolution of the target pattern formed by manufacturing is lowered, which is difficult to achieve.

The powder material may further comprise additives including at least one of flow aids, fillers. Wherein, the flow assistant is used for improving the fluidity of the powder material, and the flow assistant can be silicon dioxide, talcum powder and the like; the filler is used to improve the mechanical strength of the target model, and may be, for example, graphene, carbon nanotubes, glass fibers, kaolin, etc., without limitation in this application.

In one possible design, when the liquid composition is sprayed on the powder material layer 1 to form the target model layer 2 and the liquid composition is sprayed on at least a part of the powder material layer 1 to form the barrier layer 3, the 3D printing method specifically includes: spraying a liquid composition on the powder material layer 1 to form a target model area, and spraying a liquid composition on at least part of the powder material layer 1 to form a blocking area; energy is supplied to the powder material layer 1 to form the target model layer 2 in the target model area and to form the barrier layer 3 in the barrier area.

In this embodiment, the liquid composition is sprayed on the powder material layer 1 to form the target model region according to the cross-sectional data of the target model, and the specific manner of obtaining the cross-sectional data of the target model may be: the method comprises the steps of obtaining original data of a target model in a scanning mode, carrying out 3D modeling to obtain a digital model of the target model, or designing and constructing the target model to obtain the digital model of the target model, carrying out data type conversion on the digital model, for example, converting the digital model into a format which can be identified by slicing software, such as an STL format, a PLY format, a WRL format and the like, carrying out slicing layering on the model by using the slicing software to obtain sliced layer image data, and processing the layered image data to obtain cross section data of the target model. The cross-sectional data of the object model includes information representing the shape of the object, and/or information representing the color of the object.

Wherein a target model area is formed by spraying a liquid composition on the powder material layer 1 according to the cross-sectional data of the target model, and a barrier area is formed by spraying a liquid composition on at least a part of the powder material layer 1. And the blocking area formed on the powder material layer 1 in this embodiment is a cross-section part of a non-target model, and the data source of the blocking area may be automatically generated by data processing software when the target model is sliced and layered, or may be data stored in a storage program of a printing device.

The liquid composition is not limited in this embodiment as long as it can finally cure and mold the material on which the liquid composition is ejected. The liquid composition may be a liquid composition containing an energy absorber which, upon absorption of the energy provided, converts the energy into thermal energy, thereby melt-forming the powder material in contact therewith; or the liquid composition is a light-cured material, the liquid composition contains a light-cured component, the light-cured component can dissolve the powder material, and the light-cured component is induced by the photoinitiator to carry out polymerization reaction under the irradiation of supplied energy such as radiant energy so as to entangle and cure the dissolved powder molecules for forming; alternatively, the liquid composition is a thermosetting material, the liquid composition contains a thermosetting component, and the thermosetting component is initiated to polymerize by the thermal initiator under the irradiation of energy such as heat energy, and the formed polymer wraps the powder material.

The liquid composition at least partially dissolves the powder material, and the liquid composition may further comprise auxiliaries, which may be, for example, conventionally known materials such as initiators, leveling agents, defoamers, surfactants, and the like. The initiator is used for initiating the liquid composition to react, and can be selected from a photoinitiator, a free radical initiator, an anionic initiator, a cationic initiator and the like according to the type of the liquid composition; the leveling agent is used to improve the fluidity of the liquid composition and the wetting property of the powder material, and at the same time, to adjust the surface tension of the liquid composition so that it can be normally printed, which is not limited in this embodiment. The antifoaming agent is mainly used for preventing foaming of the liquid composition, and the antifoaming agent may be, for example, a silicone antifoaming agent, a polyether antifoaming agent, a fatty acid ester antifoaming agent, or the like; surfactants are mainly used to control the wettability, permeability and surface tension of the liquid composition to the powder material, and may be, for example, anionic surfactants, nonionic surfactants and amphoteric surfactants.

The liquid composition may further include a colorant, and when the liquid composition contains the colorant, a colored 3D object may be realized, and the colorant may be a dye or a pigment.

The method comprises the steps that a powder material layer 1, a target model layer 2 and/or a barrier layer 3 are repeatedly formed, when a target model is formed by overlapping multiple target model layers 2, whether the current target model layer 2 is the last layer is determined, and when the current target model layer 2 is determined not to be the last layer, the powder material layer 1, the target model layer 2 and/or the barrier layer 3 are repeatedly formed; when it is confirmed that the current target model layer 2 is the last layer, the target model is formed.

In one possible design, the energy is selected from at least one of radiant energy and thermal energy. Depending on the type of liquid composition, the energy supplied may vary, such as thermal energy, radiation energy, etc., wherein the radiation energy may specifically be UV radiation.

As shown in fig. 1 and 2, in one possible design the barrier layer 3 is located at the edge position of the layer of powder material 1. The liquid composition is sprayed on the powder material layer 1 according to the cross-sectional data of the target model to form a target model area, and the liquid composition is sprayed on at least part of the non-target model area on the powder material layer 1 to form a blocking area which is positioned at the edge of the powder material layer 1 and has a gap with the target model area where the liquid composition is not sprayed.

In one possible design, the amount of liquid composition per unit area of the barrier region is greater than the amount of liquid composition per unit area of the target modeled region, such that the liquid composition is in sufficient contact with the powder material to increase the consolidation strength of the powder material.

As shown in fig. 3 to 5, in one possible design, at least some of the barrier layers 3 are spaced apart in the stacking direction. The maximum distance of adjacent barrier layers 3 in the stacking direction is an integral multiple of the layer thickness of the powder material layer 1. The minimum distance of adjacent barrier layers 3 in the stacking direction is greater than or equal to zero.

Specifically, as shown in fig. 3, the barrier layer 3 is formed on the powder material layers 1d and 1e, respectively, the barrier layer 3 is not formed on the powder material layer 1f, the barrier layer 3 is formed on the powder material layers 1g and 1h, respectively, the barrier layer 3 is not formed on the powder material layer 1i, and the barrier layer 3 is formed on the powder material layers 1j and 1l, respectively. The barrier layers 3 are distributed at intervals in the laminating direction, and the barrier layers 3 are not formed at intervals after every two barrier layers 3, and the interval distance is equal to the thickness of one powder material layer 1.

As shown in fig. 4, the barrier layer 3 is formed on the powder material layer 1d, the barrier layer 3 is not formed on the powder material layers 1e and 1f, the barrier layer 3 is formed on the powder material layer 1g, the barrier layer 3 is not formed on the powder material layers 1h and 1i, the barrier layer 3 is formed on the powder material layer 1j, and the barrier layer 3 is not formed on the powder material layer 1 l. The barrier layers 3 are distributed at intervals in the laminating direction, and the barrier layers 3 are not formed at intervals of two layers after each barrier layer 3, and the interval distance is equal to the thickness of the two powder material layers 1.

As shown in fig. 5, the barrier layer 3 is formed on the left side in the powder material layer 1d, the barrier layer 3 is formed on the right side in the powder material layer 1e, the barrier layer 3 is formed on the left side in the powder material layer 1f, the barrier layers 3 are formed on the right sides in the powder material layers 1g and 1h, respectively, the barrier layer 3 is formed on the left side in the powder material layer 1i, the barrier layer 3 is formed on the right side in the powder material layer 1j, and the barrier layer 3 is formed on the left side in the powder material layer 1 l. The barrier layers 3 are distributed at intervals in the laminating direction, and the barrier layers 3 are discontinuously distributed without forming a barrier wall, so that the shearing force of the powder material in the molding cavity 61 is not generated, and the shearing force of the side wall 611 to the powder material in the molding cavity 61 is reduced.

In one possible design, the adjacent barrier layers 3 are offset in a direction perpendicular to the stacking direction, as shown in fig. 6 and 7. The minimum distance of the adjacent barrier layers 3 in the direction perpendicular to the stacking direction is greater than or equal to zero.

Specifically, as shown in fig. 6, a barrier layer 3 is formed on each layer of the powder material layer 1, the barrier layers 3 are discontinuously distributed in the stacking direction, two adjacent barrier layers 3 are connected end to end in the direction perpendicular to the stacking direction, and the distance S is the width of one barrier layer 3.

As shown in fig. 7, a barrier layer 3 is formed on each layer of the powder material layer 1, the barrier layers 3 are discontinuously distributed in the stacking direction, two adjacent barrier layers 3 do not contact each other in the direction perpendicular to the stacking direction, and the distance S' is greater than the width of one barrier layer 3. The barrier layers 3 are arranged in a staggered manner in the direction perpendicular to the stacking direction, so that no barrier wall is formed, i.e. no shear force is generated on the powder material in the molding chamber 61 and the shear force of the side walls 611 on the powder material in the molding chamber 61 is reduced.

In one possible design, the barrier layer 3 is a polygonal structure. The side length of the polygonal structure is a saw-toothed structure. The barrier layer is a net structure. The mesh structure may be a triangular structure. In this embodiment, as shown in fig. 2, the blocking area has a polygonal structure with a sawtooth-shaped side length. The barrier layer is a net structure, and the net structure can be a triangular structure. The triangular structure has good stability, and the dosage of the liquid composition can be reduced under the condition of providing enough anti-shearing force intensity.

As shown in fig. 3 to 7, in one possible design, the bedding layer 4 is formed by spraying a liquid composition on the layer of powder material 1 before spraying the liquid composition on the layer of powder material 1 to form the target model area. The bottom layer 4 is in contact with the barrier layer 3. In this embodiment, before forming the target pattern area, the liquid composition is sprayed on the powder material layers 1 of 1b and 1c to form the multiple-layered bottom layer 4, and the bottom layer 4 is in contact with the barrier layer 3, thereby improving the adhesive strength between the powder material layer 1 and the stage 612 and preventing the target pattern from being displaced during printing.

As shown in fig. 8 and 9, in one possible design, the flooring layer 4 comprises a grid structure and is provided with a plurality of layers; the density of the lattice structure of the bedding layer 4 is gradually reduced in the stacking direction. In this embodiment, the bottom layer 4 may be a grid structure, the liquid composition is sprayed at the grid lines, and the liquid composition is not sprayed in the grid, so that the amount of the liquid composition used is reduced while providing sufficient adhesive strength.

In one possible design, the amount of liquid composition per unit area of the bottom layer 4 is greater than the amount of liquid composition per unit area of the upper layer 4 when printing the bottom layer 4. In the present embodiment, from the bottom floor layer 4a to the floor layer 4d, the density of the lattice structure in the floor layer 4 is gradually decreased and the amount of the liquid composition per unit area when the bottom floor layer 4a is formed is larger than that when the upper floor layer 4 is formed, and the amount of the liquid composition is decreased while providing sufficient adhesive strength, so that the floor layer 4 can be removed easily in the post-treatment of the target model.

As shown in fig. 2, in one possible design, a draft part 5 is formed by spraying a liquid composition on the powder material layer 1, and both ends of the draft part 5 are connected to the objective mold layer 2 and the barrier layer 3. In this embodiment, a traction portion 5 exists between the target model area and the blocking area, one end of the traction portion 5 is connected with the target model area, and the other end of the traction portion is connected with the blocking area, so that the defect of warping caused by stress concentration in the target model printing process can be reduced.

In one possible design, the traction part 5 is of a grid structure. In this embodiment, the traction portion 5 may be a mesh structure, and the mesh structure may reduce the amount of the liquid composition used while providing the connection function.

As shown in fig. 10. The present embodiment also provides a printing apparatus 6, the printing apparatus 6 being configured to execute a 3D printing method, the printing apparatus 6 including: a powder supply part 62 for supplying a powder material to form the powder material layer 1; a forming chamber 61, the forming chamber 61 being provided with a side wall 611 and a platform 612, the platform 612 being adapted to carry the layer of powder material 1; a liquid dispenser 63 for spraying a liquid composition on the layer of powder material 1 to form the target model layer 2 and/or the barrier layer 3; wherein the barrier layer 3 is located between the target model layer 2 and the sidewall 611.

In this embodiment, the powder supplying component 62 pushes the powder material into the platform 612 of the forming chamber 61, so that the powder material layer 1 is formed on the platform 612, the liquid distributor 63 sprays the liquid composition on the powder material layer 1 to form the target model layer 2 and/or the barrier layer 3, and the barrier layer 3 is disposed between the target model layer 2 and the sidewall 611, that is, the barrier layer 3 segments the powder material layer 1, thereby reducing the shearing force between the powder material in the forming chamber 61 and the sidewall 611, and reducing the risk that the target model moves due to the influence of the shearing force.

The powder supply component 62 comprises a powder storage cavity 621 and a powder spreader 622, the powder storage cavity 621 is used for storing powder materials, a movable support plate 623 is arranged inside the powder storage cavity 621, and the support plate 623 can ascend or descend in the stacking direction; the powder spreader 622 is used to spread the powder material in the powder storage chamber 621 onto the platform 612 to form the powder material layer 1, and the powder spreader 622 may be a powder spreading stick or a scraper.

The liquid dispenser 63 is an ink jet print head, which may be a single channel print head or a multi-channel print head, the number of print heads in this embodiment being dependent on the type of liquid composition used and the amount of liquid composition that needs to be applied, e.g., where the liquid compositions include functional materials of different colors, the liquid compositions of different colors are ejected through different print heads or different channels of the same print head.

In one possible design, the printing device 6 further comprises a controller 64 and an energy generator 65, the controller 64 being configured to control the liquid dispenser 63 to spray the liquid composition on the layer of powder material 1 to form the target mold area and to control the liquid dispenser 63 to spray the liquid composition on at least a portion of the layer of powder material 1 to form the barrier area; the energy generator 65 is used to supply energy to the powder material layer 1 so that the liquid composition sprayed on the powder material layer 1 forms the target mold layer 2 and/or the barrier layer 3. In the present embodiment, the controller 64 controls the liquid dispenser 63 to spray the liquid composition on the powder material layer 1 to form the target model region according to the cross-sectional data of the target model, controls the liquid dispenser 63 to spray the liquid composition on at least a part of the non-target model region of at least a part of the powder material layer 1 to form the blocking region, and controls the energy generator 65 to supply energy to the powder material layer 1 to form the target model region into the target model layer 2 and the blocking region into the blocking layer 3.

In one possible design, the printing device 6 further comprises a heating member 67 for preheating the layer 1 of powder material and increasing the temperature of the powder material. Wherein the heating part 67 includes at least one of a heating lamp, a heating plate, a heating sheet, and a heating wire.

In one possible design, the printing device 6 further includes a first lifting mechanism 66 and a second lifting mechanism 68, the first lifting mechanism 66 can drive the platform 612 to ascend or descend, and the second lifting mechanism 68 can drive the powder supply component 62 to descend or ascend. In this embodiment, the first elevating mechanism 66 is connected to the platform 612 to drive the platform 612 to descend or ascend in the stacking direction, and the second elevating mechanism 68 is connected to the powder feeding member 62 to drive the powder feeding member 62 to ascend or descend in the stacking direction. As shown in fig. 10, during operation of the printing apparatus 6, the first lifting mechanism 66 controls the platform 612 to descend, and the second lifting mechanism 68 controls the powder supplying member 62 to ascend.

In one possible design, the energy generator 65 includes at least one of a UV-LED lamp, an infrared radiation lamp, a laser. The energy provided by the energy generator 65 may be radiant energy or thermal energy, and the energy generator 65 may be selected from at least one of a UV-LED lamp, an infrared radiation lamp, and a laser. It should be noted that the particular type of energy generator 65 selected is dependent upon the components of the liquid composition, and that when the liquid composition is photopolymerized, the energy generator 65 provides radiant energy, such as UV radiation, which causes the photopolymerization to occur; when the liquid composition undergoes thermal polymerization, the energy generator 65 supplies thermal energy such as infrared radiation lamps, and the thermal polymerization is initiated by the thermal energy.

The printing device 6 may also comprise a temperature monitor (not shown in the figures) for monitoring the temperature of the layer 1 of powder material.

The controller 64 is used for controlling the operation of at least one of the powder supply part 62, the liquid distributor 63, the energy generator 65, the heating part 67 and the temperature monitor. For example, the temperature monitor feeds back the monitored temperature to the controller 64, and the controller 64 controls the heating unit 67 and the power generator 65 to supply power according to the information fed back from the temperature monitor.

The present embodiment also provides a storage medium storing instructions for controlling the printing apparatus 6 to execute the 3D printing method. The storage medium includes a stored program having stored thereon instructions that control a device on which the storage medium is located to perform the 3D printing method described above.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.