Double-process composite ceramic fiber toughening direct-writing forming 3D printing platform and printing method thereof

Abstract

The invention relates to the field of ceramic additive manufacturing, in particular to a double-process composite ceramic fiber toughening direct-writing forming 3D printing platform and a printing method thereof.The platform comprises a double-nozzle multi-material extrusion forming mechanism and further comprises a three-axis displacement table driving the double-nozzle multi-material extrusion forming mechanism to conduct three-dimensional motion; a printing substrate for completing 3D printing is arranged on the three-axis displacement table; according to the method, a continuous fiber toughening ceramic extruder is used for printing an external ceramic structure, an FDM extruder is used for printing an internal filling mechanism, and the problems that in the prior art, a complex ceramic structure is difficult to form, low in precision, large in material consumption and the like can be solved.

Description

Technical Field

[0001] The present invention relates to the field of ceramic additive manufacturing, and more specifically to a dual-process composite ceramic fiber toughening direct writing 3D printing platform and a printing method thereof. Background Art

[0002] Fused Deposition Modeling (FDM) is a 3D printing technology that heats, melts and extrude various thermoplastic polymers such as PLA, PETG and ABS. The process principle is that the molding material is squeezed into the nozzle through the extrusion mechanism and heated to a molten state in the nozzle. The nozzle is installed on a multi-degree-of-freedom motion platform and makes planar motion according to the pre-set contour information and filling trajectory. After the material is melted, it is extruded through the nozzle and evenly spread on each layer of the cross-sectional contour of the part. At this time, the extruded material quickly cools and solidifies in a short time, and adheres to the solidified material of the previous layer, stacking layer by layer to finally generate the required solid parts.

[0003] Direct writing technology is a type of 3D printing technology. Its basic feature is that high-viscosity liquid or high-viscosity paste mixed with solid and liquid is stored in a material tank as printing raw material and connected to a nozzle. The nozzle is installed on a multi-degree-of-freedom mobile platform that can complete three-dimensional movement under the control of a microcontroller unit MCU. Mechanical pressure or pneumatic pressure is used to push the raw material out of the nozzle to continuously extrude and pre-form on the printing platform, and then corresponding post-processing is performed according to the material to obtain the final three-dimensional molded component.

[0004] At present, complex ceramic structures such as closed cavities / channels and hollow lattices have problems such as difficult forming, low precision and high material consumption. In addition, such ceramic components are limited by the inherent brittleness of ceramic materials and have poor ability to resist dynamic loads or impacts. Summary of the invention

[0005] The purpose of the present invention is to provide a dual-process composite ceramic fiber toughened direct writing 3D printing platform and a printing method thereof, which can solve the problems of difficult forming, low precision, and high material consumption of complex ceramic structures in the prior art.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A dual-process composite ceramic fiber toughening direct writing 3D printing platform, including a dual-nozzle multi-material extrusion molding mechanism, and also includes a three-axis displacement platform for driving the dual-nozzle multi-material extrusion molding mechanism to perform three-dimensional movement, and the three-axis displacement platform is provided with a printing substrate for completing 3D printing;

[0008] The dual-nozzle multi-material extrusion molding mechanism includes a continuous fiber toughened ceramic extruder and an FDM extruder, and the continuous fiber toughened ceramic extruder and the FDM extruder switch working states through vertical displacement;

[0009] The continuous fiber toughened ceramic extruder and the FDM extruder communicate with the MCU via the CAN bus; that is, all the controlled components on the extruder are connected to a BIGTREETECH EBB42 CAN tool board installed on the extruder, and this tool board communicates with the MCU via a four-strand wire. If the extruder needs to be dismantled, just pull out the four-strand wire;

[0010] The continuous fiber toughened ceramic extruder and the FDM extruder achieve vertical displacement through a lifting mechanism;

[0011] The lifting mechanism includes an electric push rod, the electric push rod is fixedly connected to the continuous fiber toughened ceramic extruder, the telescopic end of the electric push rod is fixedly connected to the FDM extruder, and the continuous fiber toughened ceramic extruder is slidably connected to the extrusion mechanism back plate of the FDM extruder through a pair of micro linear guide rails;

[0012] The electric push rod has two working positions, namely, extension and contraction. When the electric push rod is extended, the continuous fiber toughened ceramic extruder is lifted and the FDM extruder is in a working state. When the electric push rod is contracted, the continuous fiber toughened ceramic extruder is lowered and in a working state.

[0013] The three-axis translation platform includes a mounting platform, an X-axis moving platform, a Z-axis moving platform and a Y-axis moving platform. The printing substrate is adsorbed on the X-axis moving platform by magnetic force. The X-axis moving platform is mounted on the mounting platform through a slide rail mechanism and uses a synchronous belt drive. The Z-axis moving platform is mounted on the mounting platform through a slide rail mechanism and uses a lead screw drive. The Y-axis moving platform is mounted on the Z-axis moving platform through a slide rail mechanism and uses a synchronous belt drive.

[0014] The FDM extruder is slidably connected to the Y-axis moving platform through a linear sliding bearing, and the Y-axis moving platform drives the FDM extruder to move in the Y-axis direction through a stepping motor driving a synchronous belt;

[0015] A dual-process composite ceramic fiber toughened direct writing 3D printing method, the method uses a continuous fiber toughened ceramic extruder to print an external ceramic structure, and uses an FDM extruder to print an internal filling mechanism, the method comprising the following steps:

[0016] Step 1: The continuous fiber reinforced ceramic extruder works to complete the printing of the bottom continuous fiber reinforced ceramic structure;

[0017] Step 2: After the bottom continuous fiber-reinforced ceramic structure is printed, the number of layers that need to be filled in the cavity is reached. At this time, the continuous fiber-reinforced ceramic extruder first completes the printing of the peripheral ceramic structure, and then the FDM extruder completes the filling of the internal cavity structure and continues to stack layer by layer;

[0018] Step 3: After all the layers that need to be filled with cavities are completed, the continuous fiber reinforced ceramic extruder completes the printing of the remaining ceramic structure on the top.

[0019] The beneficial effects of the present invention are:

[0020] Through the continuous fiber-reinforced ceramic extruder and FDM extruder, fiber-reinforced ceramic 3D printing and fused deposition modeling 3D printing can be realized simultaneously. By combining the two processes, the manufacture of high-toughness ceramic cavity structures can be realized, which provides an effective solution to the difficulty in manufacturing such structures.

[0021] By improving the control signal communication mode of the dual extruder, the present invention can greatly reduce the number of lines that need to be plugged and unplugged compared to the traditional mode in which all controlled components are directly connected to the MCU, thereby realizing the rapid disassembly and installation of the continuous fiber toughened ceramic extruder and facilitating debugging and maintenance;

[0022] The three-axis translation stage is driven by a high-precision closed-loop stepper motor, so the motion accuracy can be fully guaranteed. The printing platform has an open structure with excellent scalability and is easy to modify. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0024] Figure 1 It is a schematic diagram of the structure of the double-nozzle multi-material extrusion molding mechanism of the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the dual-process composite ceramic fiber toughening direct writing 3D printing platform of the present invention;

[0026] Figure 3 It is a schematic diagram of the manufacturing process of the closed cavity structure ceramic component of the present invention.

[0027] In the figure: continuous fiber reinforced ceramic extruder 1; electric push rod 2; micro linear guide 3; extrusion mechanism back plate 4; linear sliding bearing 5; FDM extruder 6; dual nozzle multi-material extrusion molding mechanism 7; three-axis translation stage 8; printing base 9; mounting platform 10; X-axis moving platform 11; Z-axis moving platform 12; Y-axis moving platform 13. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings.

[0029] like Figures 1 to 3As shown, in order to achieve the technical effect of "solving the problems of difficult forming, low precision, and high material consumption of complex ceramic structures in the prior art", the structure and function of a dual-process composite ceramic fiber toughened direct writing molding 3D printing platform are described in detail below;

[0030] A dual-process composite ceramic fiber toughening direct writing 3D printing platform, comprising a dual-nozzle multi-material extrusion molding mechanism 7, and a three-axis displacement platform 8 for driving the dual-nozzle multi-material extrusion molding mechanism 7 to perform three-dimensional movement, and a printing substrate 9 for completing 3D printing is arranged on the three-axis displacement platform 8;

[0031] The three-axis translation stage 8 is a translation stage of the fused deposition 3D printer prusa i3 mk3s+; the FDM extruder is a supporting product of the existing fused deposition 3D printer prusa i3 mk3s+;

[0032] like Figure 1 As shown, the three-axis translation stage 8 can drive the dual-nozzle multi-material extrusion molding mechanism 7 to move and complete the three-dimensional movement in space. The dual-nozzle multi-material extrusion molding mechanism 7 can simultaneously realize fiber-reinforced ceramic 3D printing and fused deposition modeling 3D printing. By combining the two processes, the manufacture of high-toughness ceramic cavity structures can be realized. The dual-nozzle multi-material extrusion molding mechanism 7 prints on the printing substrate 9;

[0033] The continuous fiber toughened ceramic extruder 1 and the FDM extruder 6 communicate with the MCU via the CAN bus, that is, all the controlled components on the extruder are connected to a BIGTREETECH EBB42CAN tool board installed on the extruder, and the tool board communicates with the MCU via a four-strand wire;

[0034] The dual-nozzle multi-material extrusion molding mechanism 7 includes a continuous fiber toughened ceramic extruder 1 and an FDM extruder 6, and the continuous fiber toughened ceramic extruder 1 and the FDM extruder 6 switch working states through vertical displacement;

[0035] The continuous fiber toughened ceramic extruder 1 and the FDM extruder 6 realize vertical displacement through a lifting mechanism; the lifting mechanism includes an electric push rod 2, the electric push rod 2 is fixedly connected to the continuous fiber toughened ceramic extruder 1, the telescopic end of the electric push rod 2 is fixedly connected to the FDM extruder 6, and the continuous fiber toughened ceramic extruder 1 is slidably connected to the extrusion mechanism back plate 4 of the FDM extruder 6 through a pair of micro linear guide rails 3;

[0036] The electric push rod 2 has two working positions, namely, extension and shortening. When the electric push rod 2 is extended, the continuous fiber-reinforced ceramic extruder 1 is lifted and the FDM extruder 6 is in a working state. When the electric push rod 2 is shortened, the continuous fiber-reinforced ceramic extruder 1 is lowered and in a working state. By starting the electric push rod 2, the switching of the working states of the continuous fiber-reinforced ceramic extruder 1 and the FDM extruder 6 is controlled, thereby completing the fiber-reinforced ceramic 3D printing and the fused deposition modeling 3D printing.

[0037] The three-axis translation stage 8 includes a mounting platform 10, an X-axis moving platform 11, a Z-axis moving platform 12 and a Y-axis moving platform 13. The printing substrate 9 is adsorbed on the X-axis moving platform 11 by magnetic force. The X-axis moving platform 11 is mounted on the mounting platform 10 through a slide rail mechanism and is driven by a synchronous belt. The Z-axis moving platform 12 is mounted on the mounting platform 10 through a slide rail mechanism and is driven by a lead screw. The Y-axis moving platform 13 is mounted on the Z-axis moving platform 12 through a slide rail mechanism and is driven by a synchronous belt.

[0038] The FDM extruder 6 is slidably connected to the Y-axis moving platform through a linear sliding bearing 5, and the Y-axis moving platform drives the FDM extruder 6 to move in the Y-axis direction through a stepping motor driving a synchronous belt;

[0039] The X-axis stepper motor can drive the X-axis moving platform to move along the X-axis through the synchronous belt, thereby driving the printing substrate 9 to move along the X-axis, the Z-axis stepper motor can drive the Y-axis moving platform 13 to move along the Z-axis through the lead screw, and the Y-axis stepper motor can drive the dual-nozzle multi-material extrusion molding mechanism to move along the Y-axis through the synchronous belt, thereby realizing the movement of the dual-nozzle multi-material extrusion molding mechanism along the X-, Y-, and Z-axes;

[0040] A dual-process composite ceramic fiber toughened direct writing 3D printing method, the method uses a continuous fiber toughened ceramic extruder 1 to print an external ceramic structure, and uses an FDM extruder 6 to print an internal filling mechanism, the method comprising the following steps:

[0041] Step 1: The continuous fiber reinforced ceramic extruder 1 works to complete the printing of the bottom continuous fiber reinforced ceramic structure; Figure 3 (31)

[0042] Step 2: After the bottom continuous fiber-reinforced ceramic structure is printed, the number of layers required for cavity filling is reached. At this time, the continuous fiber-reinforced ceramic extruder 1 first completes the printing of the peripheral ceramic structure, and then the FDM extruder 6 completes the filling of the internal cavity structure and continues to stack layer by layer; Figure 3 (32)

[0043] Step 3: After all the layers that need to be filled in the cavity are completed, the continuous fiber reinforced ceramic extruder 1 completes the printing of the remaining ceramic structure on the top; Figure 3 (33)

[0044] After printing is completed, the parts are removed and sintered in a certain way. After sintering, the external ceramic is densified, and the internal thermoplastic polymer is decomposed into gas at high temperature, usually carbon dioxide, water and some gaseous organic compounds. Since there are many micropores in the sintered ceramic material, these gases can be discharged from these micropores to finally form a closed cavity structure. At this point, the manufacturing of continuous fiber-reinforced ceramic closed cavity components is completed. Figure 3 (34) as shown.

[0045] It should be noted that the printing mechanism here is not only suitable for cavity printing in closed spaces, but also for certain ceramic suspended structures, such as closed cavities / channels, hollow lattices, etc.

Claims

1. A dual-process composite ceramic fiber toughening direct writing 3D printing platform, comprising a dual-nozzle multi-material extrusion molding mechanism (7), characterized in that: It also includes a three-axis displacement platform (8) for driving the dual-nozzle multi-material extrusion molding mechanism (7) to perform three-dimensional movement, and a printing base (9) for completing 3D printing is arranged on the three-axis displacement platform (8).

2. A dual-process composite ceramic fiber toughened direct writing 3D printing platform according to claim 1, characterized in that: The dual-nozzle multi-material extrusion molding mechanism (7) comprises a continuous fiber toughened ceramic extruder (1) and an FDM extruder (6), and the continuous fiber toughened ceramic extruder (1) and the FDM extruder (6) switch working states through vertical displacement.

3. A dual-process composite ceramic fiber toughening direct writing 3D printing platform according to claim 2, characterized in that: The continuous fiber toughened ceramic extruder (1) and the FDM extruder (6) both communicate with the MCU via a CAN bus.

4. A dual-process composite ceramic fiber toughened direct writing 3D printing platform according to claim 2, characterized in that: The continuous fiber toughened ceramic extruder (1) and the FDM extruder (6) achieve vertical displacement through a lifting mechanism.

5. A dual-process composite ceramic fiber toughening direct writing 3D printing platform according to claim 4, characterized in that: The lifting mechanism comprises an electric push rod (2), the electric push rod (2) is fixedly connected to a continuous fiber toughened ceramic extruder (1), the telescopic end of the electric push rod (2) is fixedly connected to an FDM extruder (6), and the continuous fiber toughened ceramic extruder (1) is slidably connected to an extrusion mechanism back plate (4) of the FDM extruder (6) via a pair of micro linear guide rails (3).

6. A dual-process composite ceramic fiber toughened direct writing 3D printing platform according to claim 5, characterized in that: The electric push rod (2) has two working positions, namely, extension and contraction. When the electric push rod (2) is extended, the continuous fiber-reinforced ceramic extruder (1) is lifted and the FDM extruder (6) is in a working state. When the electric push rod (2) is contracted, the continuous fiber-reinforced ceramic extruder (1) is lowered and in a working state.

7. A dual-process composite ceramic fiber toughened direct writing 3D printing platform according to claim 2, characterized in that: The three-axis translation platform (8) comprises a mounting platform (10), an X-axis moving platform (11), a Z-axis moving platform (12) and a Y-axis moving platform (13); the printing substrate (9) is adsorbed on the X-axis moving platform (11) by magnetic force; the X-axis moving platform (11) is mounted on the mounting platform (10) by a slide rail mechanism and is driven by a synchronous belt; the Z-axis moving platform (12) is mounted on the mounting platform (10) by a slide rail mechanism and is driven by a lead screw; and the Y-axis moving platform (13) is mounted on the Z-axis moving platform (12) by a slide rail mechanism and is driven by a synchronous belt.

8. A dual-process composite ceramic fiber toughened direct writing 3D printing platform according to claim 7, characterized in that: The FDM extruder (6) is slidably connected to the Y-axis moving platform via a linear sliding bearing (5), and the Y-axis moving platform drives the FDM extruder (6) to move in the Y-axis direction via a stepping motor driving a synchronous belt.

9. A dual-process composite ceramic fiber toughening direct writing 3D printing method, characterized in that: The method uses a continuous fiber reinforced ceramic extruder (1) to print the external ceramic structure and uses an FDM extruder (6) to print the internal filling structure.

10. A dual-process composite ceramic fiber toughening direct writing 3D printing method according to claim 9, characterized in that: The method comprises the following steps: Step 1: The continuous fiber-reinforced ceramic extruder (1) works to complete the printing of the bottom continuous fiber-reinforced ceramic structure; Step 2: After the bottom continuous fiber-reinforced ceramic structure is printed, the number of layers required for cavity filling is reached. At this time, the continuous fiber-reinforced ceramic extruder (1) first completes the printing of the peripheral ceramic structure, and then the FDM extruder (6) completes the filling of the internal cavity structure and continues to stack layer by layer; Step 3: After all the layers that need to be filled with cavities are completed, the continuous fiber reinforced ceramic extruder (1) completes the printing of the remaining ceramic structure on the top.

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