CN111360253A - 3D printing support removing method - Google Patents
3D printing support removing method Download PDFInfo
- Publication number
- CN111360253A CN111360253A CN202010179210.7A CN202010179210A CN111360253A CN 111360253 A CN111360253 A CN 111360253A CN 202010179210 A CN202010179210 A CN 202010179210A CN 111360253 A CN111360253 A CN 111360253A
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- China
- Prior art keywords
- isolation layer
- main body
- printing
- acid
- nozzle
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/40—Structures for supporting workpieces or articles during manufacture and removed afterwards
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/60—Treatment of workpieces or articles after build-up
- B22F10/62—Treatment of workpieces or articles after build-up by chemical means
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/50—Means for feeding of material, e.g. heads
- B22F12/53—Nozzles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/50—Means for feeding of material, e.g. heads
- B22F12/55—Two or more means for feeding material
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- 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
- B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/10—Formation of a green body
- B22F10/18—Formation of a green body by mixing binder with metal in filament form, e.g. fused filament fabrication [FFF]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Abstract
The application discloses a 3D printing support removing method, which comprises the following steps: (1) adopting a double-nozzle printing system, wherein a main nozzle supplies a main body material, a secondary nozzle supplies an isolation layer material, and the isolation layer material is prepared by mixing at least one of acid-soluble oxide, acid-soluble inorganic salt, water-soluble material and material dissolved in organic solvent with an organic polymer solvent containing polyformaldehyde; (2) controlling the main nozzle to print the support structure; (3) after the support structure is printed, controlling the auxiliary spray head to print an isolation layer on the support structure; (4) controlling the main nozzle to print the main body member; (5) after the printing of the main body component is finished, taking down the main body component and the supporting structure for degreasing treatment and sintering treatment; (6) and (4) carrying out the degradation treatment of the isolation layer on the product obtained in the step (5), dissolving the isolation layer, and separating the main body component from the supporting structure. The support that 3D printed the product has been solved in this application and has been got rid of inefficiency, very easily causes the problem of injury to work piece itself.
Description
Technical Field
The application relates to the field of 3D printing, in particular to a 3D printing support removing method.
Background
In the field of metal 3D printing, FDM (fused deposition) printing technology is widely used. According to the technology, a printing wire formed by extruding and molding metal powder mixed with a high polymer binder is heated to a molten state through a printing nozzle and then is stacked layer by layer to form a model, most of high polymer materials are removed through a cracking reaction catalyzed by acid to obtain a degreased blank, and finally the degreased blank is sintered at a high temperature to obtain a metal part.
In the metal 3D printing process, because the forming mode is piled up for the successive layer, the printing process needs to add the support so that printing can be accomplished smoothly when unsettled, hollow structure appear in the part. The related art selects alumina ceramics as a support material printed together with a workpiece, and the support material is degreased and sintered together with the workpiece and removed by a physical method such as mechanical knocking after sintering is completed.
The biggest defect existing in the prior art is the support removing mode, when the support is removed by using a physical method, the support removing of a complex workpiece and a thin-wall workpiece is difficult to process, the workpiece is extremely easy to damage when the support is removed, and meanwhile, the support removing efficiency by using the physical method is low, the operation needs to be carried out on the workpieces one by one, and time and labor are wasted.
Aiming at the problems that the support removal efficiency of a 3D printing product is low and the workpiece is easily damaged in the related technology, an effective solution is not provided at present.
Disclosure of Invention
The application mainly aims to provide a 3D printing support removing method to solve the problems that in the related technology, the support removing efficiency of a 3D printing product is low and the workpiece is easily damaged.
In order to achieve the above object, the present application provides a 3D printing support removing method, including the steps of: (1) adopting a double-nozzle printing system, wherein a main nozzle supplies a main body material, a secondary nozzle supplies an isolation layer material, and the isolation layer material is prepared by mixing at least one of acid-soluble oxide, acid-soluble inorganic salt, water-soluble material and material dissolved in organic solvent with an organic polymer solvent containing polyformaldehyde; (2) controlling the main nozzle to print the support structure; (3) after the support structure is printed, controlling the auxiliary spray head to print an isolation layer on the support structure; (4) controlling the main nozzle to print the main body member; (5) after the printing of the main body component is finished, taking down the main body component and the supporting structure for degreasing treatment and sintering treatment; (6) and (4) carrying out the degradation treatment of the isolation layer on the product obtained in the step (5), dissolving the isolation layer, and separating the main body component from the supporting structure.
Further, the acid-soluble oxide is at least one of calcium oxide, magnesium oxide, lithium oxide, and zinc oxide.
Further, the acid-soluble inorganic salt is at least one of barium carbonate and calcium carbonate.
Further, the degradation mode in the step (6) is to soak the main body component and the support structure in a specific solution to degrade the isolation layer.
Further, the degreasing treatment in the step (5) is performed in a catalytic degreasing furnace.
Further, the sintering treatment in the step (5) is performed in a sintering furnace.
Furthermore, the thickness of the isolation layer is adjustable, and the thickness of the isolation layer is integral multiple of the diameter of the wire rod.
In the embodiment of the present application, the support structure and the main nozzle are printed by using a dual nozzle printing system in which the main nozzle prints the support structure and the main body member, and after the support structure is printed, the auxiliary nozzle prints an isolation layer on the supporting structure, the isolation layer is prepared by mixing at least one of acid-soluble oxide, acid-soluble inorganic salt, water-soluble material and material dissolved in organic solvent with organic polymer solvent containing polyformaldehyde, the main body component and the supporting structure are jointly degraded after the main body component is printed, so that the isolation layer is degraded, thereby separating the support structure from the main body member, achieving the purpose of quickly removing the support structure while maintaining the integrity of the main body member, therefore, the problems that in the related technology, the efficiency of supporting and removing a 3D printing product is low and the workpiece is easily damaged are solved.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, serve to provide a further understanding of the application and to enable other features, objects, and advantages of the application to be more apparent. The drawings and their description illustrate the embodiments of the invention and do not limit it. In the drawings:
fig. 1 is a schematic flow diagram according to an embodiment of the application.
Detailed Description
In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but 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.
It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used.
In this application, the terms "upper", "lower", "inside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.
Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.
Furthermore, the terms "disposed," "provided," "connected," "secured," and the like are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
In addition, the term "plurality" shall mean two as well as more than two.
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.
As shown in fig. 1, an embodiment of the present application provides a 3D printing support removing method, including the following steps: (1) adopting a double-nozzle printing system, wherein a main nozzle supplies a main body material, a secondary nozzle supplies an isolation layer material, and the isolation layer material is prepared by mixing at least one of acid-soluble oxide, acid-soluble inorganic salt, water-soluble material and material dissolved in organic solvent with an organic polymer solvent containing polyformaldehyde; (2) controlling the main nozzle to print the support structure; (3) after the support structure is printed, controlling the auxiliary spray head to print an isolation layer on the support structure; (4) controlling the main nozzle to print the main body member; (5) after the printing of the main body component is finished, taking down the main body component and the supporting structure for degreasing treatment and sintering treatment; (6) and (4) carrying out the degradation treatment of the isolation layer on the product obtained in the step (5), dissolving the isolation layer, and separating the main body component from the supporting structure.
In the embodiment, a dual-nozzle printing system is adopted, a main nozzle uses a main material to print a support structure and a main component, the main material can adopt materials commonly used in 3D printing in the related technology, after the support structure is printed, an auxiliary nozzle prints an isolation layer on the support structure, the isolation layer is prepared by mixing at least one of acid-soluble oxides, acid-soluble inorganic salts, water-soluble materials and materials dissolved in organic solvents with an organic polymer solvent containing polyformaldehyde, after the main component is printed, the main component and the support structure are taken down together and are subjected to degreasing treatment, the degreasing treatment can be carried out in a catalytic degreasing furnace, the end point degreasing rate is above 9%, the degreased product is subjected to sintering treatment, the sintering treatment can be carried out in the sintering furnace, the product subjected to sintering treatment is subjected to sintering molding, and finally, the molded product is subjected to isolation layer degradation treatment, the isolation layer is dissolved, so that the main body component and the supporting structure are naturally separated, and by adopting the support removing method, the purpose of quickly removing the supporting structure while keeping the integrity of the main body component is achieved, and the problems that in the related technology, the support removing efficiency of a 3D printing product is low, and the workpiece is easily damaged are solved.
As shown in fig. 1, as a preferable mode, at least one of calcium oxide, magnesium oxide, lithium oxide, and zinc oxide is used as the acid-soluble oxide, and at least one of barium carbonate and calcium carbonate is used as the acid-soluble inorganic salt.
As shown in fig. 1, as a preferable mode, the degradation mode in step (6) is to soak the main body member and the support structure in a specific solution to degrade the isolation layer, and when acid-soluble oxide is used to dissolve acid-soluble inorganic salt as the material of the isolation layer, a dilute strong acid solution containing dilute hydrochloric acid, dilute sulfuric acid, dilute nitric acid and the like is used for soaking during the degradation process as a method for removing the support structure after the sintering is finished; when a water-soluble material or a material dissolved in an organic solvent is used as the material of the isolation layer, water or the organic solvent is used for soaking during degradation treatment as a method for removing the support structure after sintering is finished, and the degradation treatment method of the two is selected according to the material of the isolation layer.
As shown in fig. 1, as a preferable mode, the thickness of the isolation layer is adjustable, the thickness of the isolation layer is integral multiple of the diameter of the wire rod, and the thickness of the isolation layer can be adjusted according to the structure of the main body component as the isolation layer is printed layer by layer through the auxiliary spray head.
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.
Claims (6)
1. A3D printing support removing method is characterized by comprising the following steps:
(1) adopting a double-nozzle printing system, wherein a main nozzle supplies a main body material, a secondary nozzle supplies an isolation layer material, and the isolation layer material is prepared by mixing at least one of acid-soluble oxide, acid-soluble inorganic salt, water-soluble material and material dissolved in organic solvent with an organic polymer solvent containing polyformaldehyde;
(2) controlling the main nozzle to print the support structure;
(3) after the support structure is printed, controlling the auxiliary spray head to print an isolation layer on the support structure;
(4) controlling the main nozzle to print the main body member;
(5) after the printing of the main body component is finished, taking down the main body component and the supporting structure for degreasing treatment and sintering treatment;
(6) and (4) carrying out the degradation treatment of the isolation layer on the product obtained in the step (5), dissolving the isolation layer, and separating the main body component from the supporting structure.
2. The 3D printing support removal method according to claim 1, wherein the acid-soluble oxide employs at least one of calcium oxide, magnesium oxide, lithium oxide, and zinc oxide.
3. The 3D printing support removing method according to claim 1, wherein the acid-soluble inorganic salt employs at least one of barium carbonate and calcium carbonate.
4. The 3D printing support removal method according to any one of claims 1 to 3, wherein the degradation manner in the step (6) is to soak the body member and the support structure in a specific solution to degrade the isolation layer.
5. The 3D printing support removal method according to claim 4, wherein the degreasing treatment in the step (5) is performed in a catalytic degreasing furnace.
6. The 3D printing support removal method according to claim 5, wherein the sintering process in step (5) is performed in a sintering furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010179210.7A CN111360253A (en) | 2020-03-17 | 2020-03-17 | 3D printing support removing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010179210.7A CN111360253A (en) | 2020-03-17 | 2020-03-17 | 3D printing support removing method |
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| CN111360253A true CN111360253A (en) | 2020-07-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010179210.7A Pending CN111360253A (en) | 2020-03-17 | 2020-03-17 | 3D printing support removing method |
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| CN (1) | CN111360253A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112024887A (en) * | 2020-08-25 | 2020-12-04 | 苏州复浩三维科技有限公司 | Method and system for optimizing printing of ceramic isolation layer |
| CN112371994A (en) * | 2020-10-22 | 2021-02-19 | 苏州复浩三维科技有限公司 | Printing method of workpiece support, support structure and workpiece with support |
| CN113478606A (en) * | 2021-06-18 | 2021-10-08 | 上海建工建材科技集团股份有限公司 | 3D printing double-nozzle device with clay as supporting material and using method |
| CN114749682A (en) * | 2022-04-07 | 2022-07-15 | 中国第一汽车股份有限公司 | Isolation material, metal 3D printing part and preparation method thereof |
| CN115255382A (en) * | 2022-07-25 | 2022-11-01 | 钟伟 | 3D printing conformal sintering supporting method and device thereof |
| CN115365513A (en) * | 2022-08-18 | 2022-11-22 | 华中科技大学 | Easy-to-remove support structure for SLM (Selective laser melting) forming and preparation method and application thereof |
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| CN106738874A (en) * | 2016-11-24 | 2017-05-31 | 南京航空航天大学 | A kind of method of quick removal 3D printing support |
| CN107586375A (en) * | 2017-10-30 | 2018-01-16 | 广东工业大学 | A kind of water-soluble support materials |
| CN109195776A (en) * | 2016-04-14 | 2019-01-11 | 德仕托金属有限公司 | Increasing material manufacturing with support construction |
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| CN105992688A (en) * | 2014-10-14 | 2016-10-05 | 花王株式会社 | Soluble material for three-dimensional molding |
| WO2017017941A1 (en) * | 2015-07-27 | 2017-02-02 | Canon Kabushiki Kaisha | Laminate molding method and program for use in the same |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112024887A (en) * | 2020-08-25 | 2020-12-04 | 苏州复浩三维科技有限公司 | Method and system for optimizing printing of ceramic isolation layer |
| US11325278B2 (en) | 2020-08-25 | 2022-05-10 | Suzhou Fusion Tech Co., Ltd. | Method and system of optimizing printing of ceramic isolation layer |
| CN112371994A (en) * | 2020-10-22 | 2021-02-19 | 苏州复浩三维科技有限公司 | Printing method of workpiece support, support structure and workpiece with support |
| CN113478606A (en) * | 2021-06-18 | 2021-10-08 | 上海建工建材科技集团股份有限公司 | 3D printing double-nozzle device with clay as supporting material and using method |
| CN114749682A (en) * | 2022-04-07 | 2022-07-15 | 中国第一汽车股份有限公司 | Isolation material, metal 3D printing part and preparation method thereof |
| CN114749682B (en) * | 2022-04-07 | 2024-03-15 | 中国第一汽车股份有限公司 | Isolation material, metal 3D printing part and preparation method thereof |
| CN115255382A (en) * | 2022-07-25 | 2022-11-01 | 钟伟 | 3D printing conformal sintering supporting method and device thereof |
| WO2024021352A1 (en) * | 2022-07-25 | 2024-02-01 | 钟伟 | 3d printing conformal sintering supporting method and device |
| CN115365513A (en) * | 2022-08-18 | 2022-11-22 | 华中科技大学 | Easy-to-remove support structure for SLM (Selective laser melting) forming and preparation method and application thereof |
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