Sunken 3D printing method and sunken 3D printing equipment

Abstract

The invention discloses a sinking type 3D printing method and sinking type 3D printing equipment. The method comprises the following steps: S1, putting a heat transfer medium into an inner cavity of a printer; s2, preparing the temperature-sensitive phase-change material into printing ink, and putting the printing ink into a charging barrel of a printer; s3, designing a model and carrying out extrusion type ink direct writing 3D printing; and S4, after printing is finished, a cleaning solution is directly used for removing the heat transfer medium from the whole printing piece, and a three-dimensional model is obtained. According to the sinking type 3D printing device, the heat transfer medium is mainly adopted for providing heat for printing ink to enable the printing ink to be subjected to phase change, and due to the fact that the printing head is located above the liquid level of the heat transfer medium, printing of the temperature-sensitive phase change material can be achieved through sinking type 3D printing.

Description

Technical Field

[0001] The present invention relates to the field of 3D printing technology, and more specifically, to a sinking 3D printing method and a sinking 3D printing device. Background Art

[0002] 3D printing technology is a revolutionary manufacturing method that brings great potential for transformation to various fields by converting digital models into physical objects. Among them, 3D printing technology for thermosetting materials has been widely applied. This technology stacks thermally curable materials layer by layer through a direct extrusion method and cures them to form a solid under appropriate conditions. It has shown great potential in industrial manufacturing, construction, medical and other fields.

[0003] However, 3D printing of thermosetting materials also has some challenges. First of all, rheology is an important consideration factor. The material needs to have a low viscosity and high fluidity so that it can be precisely controlled and maintain stability during the printing process. Secondly, choosing the right material is also crucial. Different fields have different performance requirements for materials, so careful material selection and testing are required. In addition, the performance and control ability of the printing device also have an important impact on the quality and accuracy of the finished product.

[0004] On the other hand, 3D printing technology for low-temperature phase softening materials has some limitations. Since the melting points of these materials are lower than room temperature, they cannot be printed and formed at room temperature by heating and melting.

[0005] Therefore, a new 3D printing method needs to be provided. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a sinking 3D printing method. This method uses a temperature-sensitive phase change material as printing ink and combines a heat transfer medium to achieve 3D printing.

[0007] The present invention adopts the following technical solutions:

[0008] A sinking 3D printing method, which includes the following steps:

[0009] S1: Place the heat transfer medium into the inner cavity of the printer; the heat transfer medium in this embodiment can be silicone oil;

[0010] S2: Configure the temperature-sensitive phase change material into printing ink and put it into the cartridge of the printer; among them, the temperature-sensitive phase change material can be a thermosetting polymer such as silicone rubber and epoxy resin, or a low-temperature phase change material such as paraffin and hydrogel;

[0011] S3: Design a model and perform extrusion ink direct writing 3D printing;

[0012] S4: After printing is completed, the entire printed piece is directly used to remove the heat transfer medium with a cleaning solution to obtain a three-dimensional model. The cleaning solution can be a surfactant solution such as dishwashing liquid, or an organic solvent such as n-hexane, acetone, etc.

[0013] Among them, S1 and S2 in the above steps have no sequence. They can be carried out in the order of S1 and S2, or S2 first and then S1, or S1 and S2 can be carried out simultaneously.

[0014] Among them, step S1 also includes a step of degassing the heat transfer medium; the degassing treatment is specifically to perform a vacuum treatment on the inner cavity of the printer. Among them, the negative pressure of the vacuum treatment is 200~500 kPa, the time is 10~60 min, and the temperature is 20~30 °C.

[0015] Among them, the thermosensitive phase change material in step S2 is silicone rubber, and the printing ink includes silicone rubber and a curing agent. Specifically, silicone rubber and the curing agent are mixed in a certain ratio to obtain a prepared mixture. Among them, the mass ratio of silicone rubber to the curing agent is 20:1~1:1. The curing agent can be a curing agent corresponding to silicone rubber.

[0016] Among them, step S2 also includes a step of removing bubbles from the printing ink by high-speed centrifugation or vacuum treatment;

[0017] Among them, the process of removing bubbles by high-speed centrifugation is: the rotation speed is 1500~3000 r / min, and the time is 30~10 min;

[0018] The process of removing bubbles by vacuum treatment is: the negative pressure is 300~400 kPa, the time is 30 min, and the temperature is 20~30 °C.

[0019] Among them, step S3 is specifically to design a three-dimensional model in three-dimensional modeling software, slice it to obtain Gcode and import it into a 3D printer. The printing ink in the material cylinder of the printer enters the printing syringe, and layer-by-layer printing is carried out according to the Gcode instructions, and the printing platform gradually descends in the heat transfer medium.

[0020] Among them, designing a three-dimensional model in the three-dimensional modeling software is specifically to use computer-aided design software to design a three-dimensional structure model with an irregular shape and save it as an STL file.

[0021] Among them, slicing to obtain Gcode and importing it into a 3D printer in step S3 is specifically to set parameters such as printing temperature, platform temperature, needle size, extrusion pressure, extrusion speed, aperture, internal structure, and layer thickness in the slicing software, perform slicing operations to obtain a gcode file, and the gcode file is wirelessly transmitted to the 3D printing platform through wifi.

[0022] Among them, the parameters are specifically printing temperature 0~200°C, platform temperature 0~200°C, needle size 0.05~0.2 mm, extrusion pressure 30 kPa~500 kPa, extrusion speed 5~15 mm / s, internal structure bouligand crossing and layer thickness 0.05~0.2 mm.

[0023] Preferably, the heat transfer medium is silicone oil, and the thermosensitive phase change material is Dow Corning Sylgard 184 silicone rubber.

[0024] Among them, the print head of the 3D printer is located above the liquid level of the heat transfer medium.

[0025] A sinking 3D printing device, the sinking 3D printing device is provided with a temperature sensor, a temperature controller and a temperature regulating device. Among them, the temperature sensor is used to collect the temperature of the heat transfer medium, the temperature controller is used to receive the signal of the temperature sensor and compare it with the preset temperature value, and then send a temperature control signal for heating / cooling the heat transfer medium to the temperature regulating device, and the temperature regulating device is used to heat / cool the heat transfer medium.

[0026] The beneficial effects of the present invention are as follows:

[0027] (1) The present invention mainly uses a heat transfer medium to provide heat for the printing ink to cause a phase change. Since the print head is located above the liquid level of the heat transfer medium, the sinking 3D printing of the present invention can realize the printing of thermosensitive phase change materials.

[0028] (2) The present invention can print three-dimensional complex structures of various thermosensitive phase change materials without support.

[0029] (3) Through layer-by-layer printing, with the heat transfer medium as the support material, the present invention can achieve 100% utilization of the ink material. Description of the Drawings

[0030] Figure 1 is an overall schematic diagram of the structure of the sinking 3D printing device of the present invention.

[0031] Figure 2 is a partial schematic diagram of the sinking 3D printing device of the present invention.

[0032] The reference numerals are: 100 - print head; 200 - inner cavity; 210 - main cavity; 220 - auxiliary cavity; 300 - temperature sensor; 400 - temperature controller; 500 - temperature regulating device. Detailed Embodiments

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] Participate Figure 1 , a sunken 3D printing device, including a print head 100 and an inner cavity 200. Among them, the print head 100 is communicated with the cartridge of the printer (not shown in the figure), and the printing ink in the cartridge can enter the print head 100 for printing.

[0035] The print head 100 can move in the x, y, and z directions. The inner cavity 200 is used to place the heat transfer medium. During 3D printing, the print head 100 is always located above the inner cavity 200. Preferably, the distance between the print head 100 and the liquid surface of the heat transfer medium is 0.1 mm to 1 mm.

[0036] Preferably, refer to Figure 1 , the inner cavity 200 includes a main cavity 210 and an auxiliary cavity 220. The main cavity 210 and the auxiliary cavity 220 are communicated through a communication port. At the start of 3D printing, the heat transfer medium is placed in the main cavity 210. As 3D printing progresses, part of the heat transfer medium flows into the auxiliary cavity 220, thereby maintaining the distance between the print head and the liquid surface of the heat transfer medium.

[0037] In one of the embodiments, refer to Figure 2 , the sunken 3D printing device of the present invention is further provided with a temperature sensor 300, a temperature controller 400, and a temperature control device 500. Among them, the temperature sensor 300 is arranged in the heat transfer medium and is used to collect the temperature of the heat transfer medium. The temperature controller 400 is used to receive the signal of the temperature sensor 300, compare it with a preset temperature value, and then send a temperature control signal for heating / cooling the heat transfer medium to the temperature control device 500. The temperature control device 500 is used to perform heating / cooling treatment on the heat transfer medium. The temperature control device 500 can be a liquid working medium temperature control device, and the temperature control device 500 is arranged outside the inner cavity 200.

[0038] The temperature sensor of the sunken printing device of the present invention collects the temperature in the liquid and transmits it to the temperature controller. The temperature controller compares the measured temperature of the liquid with the preset temperature value for curing the printing material, generates a temperature control signal for heating / cooling the liquid, and controls the heater to heat / cool the liquid, so that the temperature of the liquid at the printing location is the same as the preset temperature value. Since the print head is above the liquid surface of the heat transfer medium, complex heat preservation facilities are not required, and the printing ink in the syringe can also be prevented from undergoing a phase change in advance.

[0039] Example 1

[0040] A sunken 3D printing method, using the aforementioned 3D printing equipment, includes the following steps:

[0041] S1: Use silicone oil liquid as the heat transfer matrix, evacuate the inner cavity of the printer, and perform degassing treatment on the heat transfer matrix; wherein, the negative pressure for degassing treatment is 200 kPa, the time is 10 min, and the temperature is 30 °C;

[0042] S2: Use Dow Corning Sylgard 184 silicone rubber as the thermosensitive phase change material, mix Dow Corning Sylgard 184 silicone rubber with the corresponding curing agent according to a ratio of 20:1 to obtain the prepared PDMS silica gel, and then perform high-speed centrifugation on the prepared PDMS silica gel at room temperature to remove air bubbles, and load the PDMS silica gel with removed air bubbles into the printer's matching cartridge for standby. Among them, the process of removing air bubbles by high-speed centrifugation is a rotation speed of 1500 r / min and a time of 30 min.

[0043] S3: Use computer-aided design software such as Solidworks to design a three-dimensional structure model with irregular shape and save it as an STL file; set parameters such as printing temperature, platform temperature, needle size, extrusion pressure, extrusion speed, pore size, internal structure, and layer thickness in the slicing software, and perform slicing operation to obtain a gcode file; the gcode file obtained by the slicing software is wirelessly transmitted to the 3D printing platform through wifi; after the 3D printing platform receives the gcode file, it starts to execute commands, the printing needle extrudes layer by layer, and the printing platform gradually descends in the heat transfer liquid medium. Thus, the designed printing model is printed.

[0044] Specifically, the printing temperature is 180 °C, the platform temperature is 180 °C, the needle size is 0.05 mm, the extrusion pressure is 30 kPa, the extrusion speed is 5 mm / s, the internal structure is bouligand crossing, and the layer thickness is 0.05 mm.

[0045] S4: After printing, directly use n-hexane solution to remove the heat transfer medium from the whole printed part to obtain the designed three-dimensional model.

[0046] Example 2

[0047] A sunken 3D printing method, using the aforementioned 3D printing equipment, includes the following steps:

[0048] S1: Use silicone oil liquid as the heat transfer medium, evacuate the inner cavity of the printer, and perform degassing treatment on the heat transfer medium; wherein, the negative pressure for degassing treatment is 500 kPa, the time is 60 min, and the temperature is 20 °C;

[0049] S2: Use Dow Corning Sylgard 184 silicone rubber as the thermosensitive phase change material. Mix Dow Corning Sylgard 184 silicone rubber with the curing agent in a ratio of 1:1 to obtain the prepared PDMS silica gel. Then, perform high-speed centrifugation on the prepared PDMS silica gel at room temperature to remove air bubbles, and load the PDMS silica gel without air bubbles into the printer's matching cartridge for standby. The process of removing air bubbles by high-speed centrifugation is as follows: the rotation speed is 3000 r / min, and the time is 10 min.

[0050] S3: Use computer-aided design software such as Solidworks to design a three-dimensional structure model with irregular shape and save it as an STL file; set parameters in the slicing software as printing temperature, platform temperature, needle size, extrusion pressure, extrusion speed, pore size, internal structure, and layer thickness, and perform slicing operation to obtain a gcode file; the gcode file obtained by the slicing software is wirelessly transmitted to the 3D printing platform through wifi; after the 3D printing platform receives the gcode file, it starts to execute the command, and the printing needle extrudes layer by layer, and the printing platform gradually descends in the heat transfer liquid medium. Thus, the designed printing model is printed.

[0051] Specifically, the printing temperature is 200 °C, the platform temperature is 200 °C, the needle size is 0.2 mm, the extrusion pressure is 500 kPa, the extrusion speed is 15 mm / s, the internal structure is bouligand crossing, and the layer thickness is 0.2 mm.

[0052] S4: After printing, directly use a dishwashing liquid solution to remove the heat transfer medium from the whole printed part to obtain the designed three-dimensional model.

[0053] Example 3

[0054] A sunken 3D printing method, using the aforementioned 3D printing equipment, includes the following steps:

[0055] S1: Use silicone oil liquid as the heat transfer medium, evacuate the printer's inner cavity, and perform degassing treatment on the heat transfer medium; among them, the negative pressure for degassing treatment is 300 kPa, the time is 40 min, and the temperature is 25 °C;

[0056] S2: Use liquid paraffin as the thermosensitive phase change material, and then perform vacuum treatment on the liquid paraffin at room temperature to remove air bubbles, and load the liquid paraffin without air bubbles into the printer's matching cartridge for standby. Among them, the process of removing air bubbles by vacuum treatment is a negative pressure of 300 - 400 kPa, the time is 30 min, and the temperature is 20 - 30 °C.

[0057] S3: Use computer-aided design software such as Solidworks to design a three-dimensional structure model with an irregular shape and save it as an STL file; set parameters in the slicing software as printing temperature, platform temperature, needle size, extrusion pressure, extrusion speed, hole diameter, internal structure, and layer thickness, and perform slicing operations to obtain a gcode file; the gcode file obtained by the slicing software is wirelessly transmitted to the 3D printing platform through wifi; after receiving the gcode file, the 3D printing platform starts to execute commands, and the printing needle extrudes layer by layer while the printing platform gradually descends within the heat transfer liquid medium. Thus, the designed printing model is printed.

[0058] Specifically, the printing temperature is 10°C, the platform temperature is 10°C, the needle size is 0.1 mm, the extrusion pressure is 200 kPa, the extrusion speed is 10 mm / s, the internal structure is bouligand crossing, and the layer thickness is 0.1 mm.

[0059] S4: After printing, directly use acetone solution to remove the heat transfer medium from the entire printed part to obtain the designed three-dimensional model.

[0060] It is easy for those skilled in the art to understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

[0061] The parts not elaborated in detail in the specification of the present invention belong to the well-known technology in the art. The above embodiments are provided only for the purpose of describing the present invention and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims. All equivalent replacements and modifications made without departing from the spirit and principles of the present invention shall be covered within the scope of the present invention.

Claims

1. A sunken 3D printing method, characterized in that: It includes the following steps: S1: Place the heat transfer medium into the inner cavity of the printer; S2: Configure the thermosensitive phase change material into printing ink and put it into the cartridge of the printer; the thermosensitive phase change material is a thermosetting polymer or a low-temperature phase change material; S3: Design a model and perform extrusion-based ink direct writing 3D printing; S4: After printing, directly use a cleaning solution to remove the heat transfer medium from the whole printed part to obtain a three-dimensional model.

2. The sunken 3D printing method according to claim 1, characterized in that: Step S1 further includes a step of degassing the heat transfer medium; the degassing treatment is specifically to perform a vacuum treatment on the inner cavity of the printer, wherein the negative pressure of the vacuum treatment is 200~500 kPa, the time is 10~60 min, and the temperature is 20~30 °C.

3. The sunken 3D printing method according to claim 1, wherein: In step S2, the thermosensitive phase change material is silicone rubber, and the printing ink includes silicone rubber and a curing agent. Specifically, the silicone rubber and the curing agent are mixed in a certain ratio to obtain a prepared mixture, wherein the mass ratio of the silicone rubber to the curing agent is 20:1~1:

1.

4. The sunken 3D printing method according to claim 3, wherein: Step S2 further includes a step of removing bubbles from the printing ink by high-speed centrifugation or vacuum treatment; Among them, the process of removing bubbles by high-speed centrifugation is: the rotation speed is 1500~3000 r / min, and the time is 10~30 min; The process of removing bubbles by vacuum treatment is: the negative pressure is 300~400 kPa, the time is 30 min, and the temperature is 20~30 °C.

5. The sink-type 3D printing method according to claim 3, characterized in that: Step S3 is specifically to design a three-dimensional model in three-dimensional modeling software, slice it to obtain Gcode and import it into a 3D printer. The printing ink in the cartridge of the printer enters the printing syringe, and layer-by-layer printing is performed according to the Gcode instructions. The printing platform gradually descends in the heat transfer medium.

6. The sunken 3D printing method according to claim 5, characterized in that: Designing a three-dimensional model in the three-dimensional modeling software is specifically to use computer-aided design software to design a three-dimensional structure model with an irregular shape and save it as an STL file.

7. The sunken 3D printing method according to claim 1, characterized in that: Slicing to obtain Gcode and importing it into a 3D printer in step S3 is specifically to set parameters in the slicing software as printing temperature, platform temperature, needle size, extrusion pressure, extrusion speed, pore size, internal structure, and layer thickness, perform slicing operations to obtain a gcode file, and the gcode file is wirelessly transmitted to the 3D printing platform through wifi.

8. The sunken 3D printing method according to claim 7, characterized in that: The parameters are specifically printing temperature 0~200 °C, platform temperature 0~200 °C, needle size 0.05~0.2 mm, extrusion pressure 30 kPa~500 kPa, extrusion speed 5~15 mm / s, internal bouligand cross-filling structure, and layer thickness 0.05~0.2 mm.

9. The sink-type 3D printing method according to any one of claims 1 to 8, characterized in that: The print head of the 3D printer is located above the liquid level of the heat transfer medium.

10. A sunken 3D printing device, characterized in that: The sinking 3D printing device is provided with a temperature sensor, a temperature controller, and a temperature regulating device. Among them, the temperature sensor is used to collect the temperature of the heat transfer medium, the temperature controller is used to receive the signal of the temperature sensor, compare it with the preset temperature value, and then send a temperature control signal for heating / cooling the heat transfer medium to the temperature regulating device, and the temperature regulating device is used to perform heating / cooling treatment on the heat transfer medium.

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