Ceramic slurry direct writing forming laser processing layer-by-layer composite manufacturing method
By printing periodic grooves on the top surface of each printing layer in ceramic slurry direct writing additive manufacturing and embedding the next layer, the problem of density reduction caused by layer gap is solved, and the high density and strength of ceramic parts are achieved.
Patent Information
- Application Number
- CN202510241261.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-03
- Publication Date
- 2025-04-25
AI Technical Summary
In the process of direct writing additive manufacturing of ceramic slurry, gaps are easily generated due to insufficient viscosity and gravity between layers, resulting in a decrease in the density of ceramic components.
The ceramic slurry direct writing molding laser processing layer by layer composite manufacturing method is adopted. By printing periodic grooves on the top surface of each printing layer and embedded in the grooves after the next printing layer is printed, the contact area between adjacent printing layers is increased and the connection environment is improved.
By increasing the contact area between the printing layers and improving the connection environment, the density and interlayer bonding force of the ceramic parts are significantly improved.
Smart Images
Figure CN119871635A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of additive manufacturing technology, and in particular to a layer-by-layer composite manufacturing method of ceramic slurry direct writing laser processing. Background Art
[0002] At present, in the slurry direct writing additive manufacturing process, due to the high viscosity and certain self-support of DIW slurry, the current layer of slurry only relies on its own viscosity and gravity to combine with the previous layer of slurry, which leads to gaps between layers, resulting in a decrease in the density of ceramic components, affecting the density of ceramic components.
[0003] Therefore, a composite molding method is needed to improve the density of ceramic parts manufactured by DIW slurry direct writing additive manufacturing. Summary of the invention
[0004] Based on this, it is necessary to provide a ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method to overcome the defects mentioned in the above background technology.
[0005] A ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method, the method comprising the following steps: after each printing layer of the ceramic green body is printed, periodic grooves are printed along the top surface thereof.
[0006] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method of the present invention, the method further comprises the following steps: Step 1: Divide the ceramic green body to be printed into multiple printing layers from bottom to top, wherein the printing layers include a plurality of self-repairing layers and a plurality of adjustment layers, wherein the first layer is a self-repairing layer, and the adjustment layers are arranged between the respective repairing layers, and are printed sequentially from bottom to top; Step 2: Print the current printing layer and initially finalize it. After initial finalization, obtain the correction area and remove it; Step 3: Print the next layer. If the next printing layer is a self-repairing layer, repeat step 2. If the next printing layer is an adjustment layer, its top surface height value needs to be compared with the theoretical value, and the adjustment layer should be corrected according to the comparison value or filled in the next layer of the adjustment layer; Step 4, repeating steps 2 and 3 layer by layer until a ceramic green body is obtained; Step 5: Heat and shape the ceramic green body.
[0007] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method of the present invention, the step 2 specifically includes: After the current printing layer is initially formed, the arc-shaped structures at both ends of the current printing layer are ablated according to the preset laser processing parameters to remove the part of the end of the current printing layer that cannot contact with the next printing layer, leaving only the part that is in close contact.
[0008] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method of the present invention, the periodic grooves are perpendicular to the extension direction of the printing path, and their size is smaller than that of the printing path.
[0009] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method of the present invention, the step 2 further comprises: When the current printing layer includes a hollow structure, after printing is completed, the intersection of the printing paths is trimmed with a laser to remove the overflowed material.
[0010] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method in the present invention, the method is implemented using an equipment, which includes: a mounting frame, a two-dimensional motion platform arranged along the X-axis direction of the equipment is provided at the lower part of one side of the mounting frame, and a slurry direct writing printing module, a heating module, a visual inspection module and a laser processing module arranged in sequence are provided above the two-dimensional motion.
[0011] As a preferred embodiment of the layer-by-layer composite manufacturing method of ceramic slurry direct writing laser processing in the present invention, the two-dimensional motion platform includes a motion X-axis, which extends along the X-axis direction, and the motion X-axis is provided with a motion Z-axis extending along the Z-axis direction. The motion Z-axis is slidably connected to the motion X-axis through a connector, and the motion Z-axis is provided with a workbench slidably connected thereto. The workbench includes a workbench bracket, one side of which is slidably connected to the motion Z-axis, and the top of which is provided with a heat insulation layer and a printing substrate in sequence from bottom to top.
[0012] As a preferred embodiment of the layer-by-layer composite manufacturing method of ceramic slurry direct writing laser processing in the present invention, the slurry direct writing printing module includes a Y-axis bracket and a nozzle assembly, the Y-axis bracket is provided with a driving assembly, the driving assembly is provided with a print head bracket that can slide along the Y-axis direction, the nozzle assembly is connected to the print head bracket, and its spraying end is facing the direction of the two-dimensional motion platform.
[0013] As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method in the present invention, the heating module includes a heating lamp, which is connected to the mounting frame through a heating lamp bracket, and the heating end of the heating lamp is oriented in the direction of the two-dimensional motion platform. As a preferred embodiment of the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method in the present invention, the visual inspection module includes a detection head, which is connected to the mounting frame through a detection head bracket, and the detection end of the detection head is facing the direction of the two-dimensional motion platform.
[0014] Beneficial effects of the present invention: The present invention processes a specific microstructure of periodic grooves on the top surface of the printed layer. After the next printed layer is printed, its bottom is embedded in the periodic grooves, thereby increasing the contact area between adjacent printed layers and improving the connection environment at the connection between adjacent printed layers, making the connection between adjacent printed layers tighter and improving the density of ceramic parts. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 Schematic diagram of the manufacturing method in the embodiment of the present application; Figure 2 This is one of the overall structural diagrams of the device in the embodiment of the present application; Figure 3 This is the second schematic diagram of the overall structure of the device in the embodiment of the present application; Figure 4 This is a schematic diagram of the structure of the slurry direct writing printing module in the embodiment of the present application; Figure 5 This is a working schematic diagram of a printing station in an embodiment of the present application; Figure 6 This is a schematic diagram of the working of the heating station in the embodiment of the present application; Figure 7 This is a working schematic diagram of the detection station in the embodiment of the present application; Figure 8 This is a working schematic diagram of a laser processing station in an embodiment of the present application; Description of reference numerals: 101, mounting frame; 102, detection head; 103, laser processing head; 104, printing substrate; 105, thermal insulation layer; 106, moving X-axis; 107, connector; 108, workbench bracket; 109, moving Z-axis; 110, heating lamp bracket; 111, heating lamp; 112, detection head bracket; 113, processing head bracket; 2. Slurry direct writing printing module; 201. Y-axis bracket; 202. Y-axis guide rod; 203. Lead screw; 204. Print head buckle; 205. Print nozzle; 206. Slurry storage tank; 207. Print head bracket; 208. Air inlet; 209. Drive motor; 3. Ceramic green body. DETAILED DESCRIPTION
[0017] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.
[0018] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0019] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0020] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0021] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0022] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.
[0023] Example This embodiment provides a ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method, such as Figure 1 As shown, the method comprises the following steps: Step 1: Divide the ceramic green body 3 to be printed into multiple printing layers from bottom to top, wherein the printing layers include a plurality of self-repairing layers and a plurality of adjustment layers, wherein the first layer is a self-repairing layer, and the adjustment layers are arranged between the respective repairing layers, and are printed sequentially from bottom to top; Step 2: Print the current printing layer and initially shape it. After the initial shaping, obtain and remove the correction area, and print periodic grooves along its top surface; Step 3: Print the next layer. If the next printing layer is a self-repairing layer, repeat step 2. If the next printing layer is an adjustment layer, its top surface height value needs to be compared with the theoretical value, and the adjustment layer should be corrected according to the comparison value or filled in the next layer of the adjustment layer; Step 4, repeating steps 2 and 3 layer by layer until a ceramic green body 3 is obtained; Step 5: heating and shaping the ceramic green body 3.
[0024] In this embodiment, the step 2 specifically includes: After the current printing layer is initially finalized, an ultrafast laser is used to process periodic grooves on the top surface of the printing layer and the processing layer according to the preset laser processing parameters, and the arc structures at both ends of the current printing layer or processing layer are ablated to remove the parts of the end of the printing layer or processing layer that cannot contact the next printing layer or processing layer, leaving only the parts in close contact. In this way, when printing the next layer, the extruded slurry can fully contact the current printing layer, thereby improving the interlayer adhesion performance and thus improving the strength and density of the component.
[0025] In this embodiment, in step 3, it is also necessary to compare the top surface height value with the theoretical value, and to correct the adjustment layer or fill in the next layer of the adjustment layer according to the comparison value, specifically including: After the processing layer is printed, the top surface of the current ceramic green body 3 is scanned, and its height value is compared with the theoretical value. When the actual height value is less than the theoretical value, the difference between the two is recorded and compensated by adding printing layers. When the actual height is greater than the theoretical value, the contour of the raised area is extracted, and the corresponding scanning path is generated in the area according to the preset laser processing parameters. Laser scanning and ablation are performed along the path to remove the raised part on the top of the green body.
[0026] In this embodiment, the periodic grooves are perpendicular to the extension direction of the printing path or arranged along other specific orientations, and their dimensions such as width and depth are smaller than the dimensions of the printing path. This structure enables the bottom of the next printing layer to be embedded in the periodic grooves after printing, thereby increasing the contact area between adjacent printing layers and improving the connection environment at the connection between adjacent printing layers, thereby increasing the interlayer bonding force and further improving the density of the parts.
[0027] In this embodiment, if the current printing layer includes a hollow structure, the overlapped parts of the printed materials between the layers of the ceramic green body 3 will be deformed due to gravity, resulting in the overflow of materials in the horizontal direction, resulting in inconsistent shrinkage rates during sintering of the ceramic green body 3. When printing such structures, after each layer is printed, the intersection of the printing paths can be trimmed using an ultrafast laser to remove the overflowed materials, so that the line width at each location remains uniform, so that the shrinkage rates at each location of the ceramic green body 3 during sintering are as consistent as possible, reducing the internal stress of the parts and avoiding cracking of the ceramic parts.
[0028] This embodiment also provides a device for implementing the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method, such as Figure 2 and Figure 3 As shown, the device includes: a mounting frame 101, a two-dimensional motion platform arranged along the X-axis direction of the device is provided at the lower part of one side of the mounting frame 101, and a slurry direct writing printing module 2, a heating module, a visual inspection module and a laser processing module arranged in sequence are provided above the two-dimensional motion.
[0029] In this embodiment, the two-dimensional motion platform includes a motion X-axis 106, which extends along the X-axis direction of the device. The motion X-axis 106 is provided with a motion Z-axis 109 extending along the Z-axis direction of the device. The motion Z-axis 109 is slidably connected to the motion X-axis 106 through a connector 107. The motion X-axis 106 and the motion Z-axis 109 are driven by an external motor to achieve movement in two directions. The motion Z-axis 109 is provided with a workbench slidably connected to it.
[0030] In this embodiment, the workbench includes a workbench bracket 108, one side of which is slidably connected to the moving Z axis 109, and the top of the workbench is provided with a heat insulation layer 105 and a printing substrate 104 from bottom to top. The printing substrate 104 is threadedly connected to the heat insulation layer 105. Holes are left in the printing substrate 104 for installing heating wires and thermocouples, which can heat the printing substrate 104 at a constant temperature to keep the bottom temperature of the ceramic green body 3 constant during the printing process.
[0031] like Figure 4 As shown, the slurry direct writing printing module 2 includes a Y-axis bracket 201 and a nozzle assembly, the Y-axis bracket 201 is provided with a driving assembly, the driving assembly includes a lead screw 203 and a driving motor 209, one end of the lead screw 203 is rotatably connected to the Y-axis bracket 201, and the other end thereof is transmission-connected to the driving motor 209, and the two sides of the lead screw 203 are provided with a Y-axis guide rod 202, and the lead screw 203 is provided with a print head bracket 207 that is screwed and connected thereto, and the two ends thereof are slidably connected to the Y-axis guide rod 202 to limit it, and the print head bracket 207 can move along the Y-axis direction under the drive of the driving assembly. The nozzle assembly includes a slurry storage tank 206, the output end of which is provided with a printing nozzle 205 facing the direction of the two-dimensional motion platform, and the top of which is provided with an air inlet 208 for connecting to an air pump; the slurry storage tank 206 is detachably connected to the print head bracket 207 through the print head buckle 204 at the bottom of the print head bracket 207.
[0032] In this embodiment, the heating module includes a heating lamp 111 , which is connected to the mounting frame 101 via a heating lamp bracket 110 , and the heating end of the heating lamp 111 faces the direction of the two-dimensional motion platform.
[0033] In this embodiment, the visual inspection module includes a detection head 102, which is connected to the mounting frame 101 through a detection head bracket 112. The detection end of the detection head 102 faces the direction of the two-dimensional motion platform. The detection head 102 is connected to an external controller and a computer through a data cable.
[0034] In this embodiment, the laser processing module includes a laser processing head 103, which is connected to the mounting frame 101 through a processing head bracket 113. The output end of the laser processing head 103 is facing the direction of the two-dimensional motion platform. The laser enters the laser processing head 103 through an external laser and an optical path, and is then emitted from the laser processing head 103 and focused on the workpiece surface. The processing head can realize the movement of the focused light spot on the XOY plane according to the planned path.
[0035] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0036] The method of using the above device includes the following steps: S1, loading ceramic slurry into the slurry storage tank 206, fixing the slurry storage tank 206 on the print head bracket 207 via the print head buckle 204, and connecting the air inlet 208 on the top of the slurry storage tank 206 to the air pump.
[0037] S2, such as Figure 5 As shown, the workbench and the printing nozzle 205 are moved to the printing station and positioned at the starting position of printing, the air pump is turned on, and the slurry in the slurry storage tank 206 is pressed out from the printing nozzle 205 by high-pressure gas, and the pressed slurry is deposited on the printing substrate 104. The X-axis of the two-axis motion platform is linked with the Y-axis of the printing module, so that the print head prints according to a preset path to obtain a layered ceramic green body 3; after the ceramic green body 3 of the current printing layer is printed, the air pump stops supplying gas, the pressure in the slurry storage tank 206 returns to normal, and the slurry stops being pressed out.
[0038] S3, such as Figure 6 As shown, after one layer of printing is completed, the two-axis motion platform drives the workbench to move to the heating station, and the heating lamp 111 starts to work, so that the solvent in the ceramic green body 3 evaporates and the green body is initially consolidated. After the heating is completed, the heating lamp 111 is turned off.
[0039] S4, the two-axis motion platform drives the workbench to move to the laser processing station, and the external laser and laser processing head 103 start working. According to the preset laser processing parameters, ultrafast laser is used to process periodic grooves on the top surface of the printed layer, and the arc-shaped structures at both ends of the current printed layer are ablated to remove the end of the current printed layer that cannot contact the next printed layer. After the processing and ablation are completed, the external laser and laser processing head 103 are turned off, and the workbench returns to the printing station.
[0040] S5, repeat S2 to S4 until the correction layer processing is completed.
[0041] S6, such as Figure 7 As shown, after the correction layer is processed, the two-axis motion platform drives the workbench to move to the detection station, and the detection head 102 starts to work. The two-axis motion platform drives the workbench to move at a uniform speed along the X direction, so that the line laser emitted by the detection head 102 evenly scans the top surface of the ceramic green body 3, and obtains the three-dimensional data of the top surface of the ceramic green body 3.
[0042] S7, such as Figure 8As shown, after the detection and comparison is completed, if the actual height is greater than the theoretical height, the two-axis motion platform drives the workbench to move to the laser processing station, and the external laser and laser processing head 103 start working. According to the data obtained from the visual detection, the laser processing path is planned to ablate the top surface of the ceramic green body 3, eliminate the accumulated layer thickness error of the printing, and process a special microstructure to improve the interlayer bonding performance of the green body. If the actual height is less than the theoretical height, the difference between the two is recorded and compensated by increasing the number of printing layers.
[0043] S8, repeat S5, S6 and S7 until the printing and ablation of the last layer are completed to obtain a complete ceramic green body 3.
[0044] S9, the ceramic green body 3 is removed from the printed substrate 104, and is subjected to drying and sintering steps to form a ceramic part.
[0045] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.
Claims
1. A ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method, characterized in that: The method comprises the following steps: after each printing layer of the ceramic green body is printed, periodic grooves are printed along the top surface thereof. (Processing periodic grooves is the main distinguishing technical feature of this application and needs to be placed in the exclusive right).
2. According to claim 1, the ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method is characterized in that: The following steps are also included: Step 1: Divide the ceramic green body to be printed into multiple printing layers from bottom to top, wherein the printing layers include a plurality of self-repairing layers and a plurality of adjustment layers, wherein the first layer is a self-repairing layer, and the adjustment layers are arranged between the respective repairing layers, and are printed sequentially from bottom to top; Step 2: Print the current printing layer and initially finalize it. After initial finalization, obtain the correction area and remove it; Step 3: Print the next layer. If the next printing layer is a self-repairing layer, repeat step 2. If the next printing layer is an adjustment layer, its top surface height value needs to be compared with the theoretical value, and the adjustment layer should be corrected according to the comparison value or filled in the next layer of the adjustment layer; Step 4, repeating steps 2 and 3 layer by layer until a ceramic green body is obtained; Step 5: Heat and shape the ceramic green body.
3. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 2 is characterized in that: The step 2 specifically includes: After the current printing layer is initially formed, the arc-shaped structures at both ends of the current printing layer are ablated according to the preset laser processing parameters to remove the part of the end of the current printing layer that cannot contact with the next printing layer, leaving only the part that is in close contact.
4. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 3 is characterized in that: The step 2 also includes: When the current printing layer includes a hollow structure, after printing is completed, the intersection of the printing paths is trimmed with a laser to remove the overflowed material.
5. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 1, characterized in that: The periodic grooves are perpendicular to the extending direction of the printing track, and the size of the periodic grooves is smaller than the size of the printing track.
6. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 1, characterized in that: The method is implemented using a device, which includes: a mounting frame, a two-dimensional motion platform arranged along the X-axis direction of the device is provided at the lower part of one side of the mounting frame, and a slurry direct writing printing module, a heating module, a visual inspection module and a laser processing module are arranged in sequence above the two-dimensional motion.
7. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 6, characterized in that: The two-dimensional motion platform includes a motion X-axis extending in the X-axis direction, the motion X-axis is provided with a motion Z-axis extending in the Z-axis direction, the motion Z-axis is slidably connected to the motion X-axis through a connector, a workbench slidably connected thereto is provided on the motion Z-axis, the workbench includes a workbench bracket, one side of which is slidably connected to the motion Z-axis, and a heat insulation layer and a printing substrate are sequentially provided on the top of the workbench from bottom to top.
8. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 6, characterized in that: The slurry direct writing printing module includes a Y-axis bracket and a nozzle assembly, the Y-axis bracket is provided with a driving assembly, the driving assembly is provided with a print head bracket that can slide along the Y-axis direction, the nozzle assembly is connected to the print head bracket, and its spraying end faces the direction of the two-dimensional motion platform.
9. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 6, characterized in that: The heating module comprises a heating lamp, which is connected to the mounting frame via a heating lamp bracket, and the heating end of the heating lamp faces the direction of the two-dimensional motion platform.
10. The ceramic slurry direct writing laser processing layer-by-layer composite manufacturing method according to claim 6, characterized in that: The visual inspection module comprises a detection head, which is connected to a mounting frame via a detection head bracket, and a detection end of the detection head faces the direction of the two-dimensional motion platform.