CN114536744A - Spatial framework composite material based on multi-material 3D printing technology - Google Patents
Spatial framework composite material based on multi-material 3D printing technology Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
- B29C64/106—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
- B29C64/171—Processes of additive manufacturing specially adapted for manufacturing multiple 3D objects
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/30—Auxiliary operations or equipment
- B29C64/386—Data acquisition or data processing for additive manufacturing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/30—Auxiliary operations or equipment
- B29C64/386—Data acquisition or data processing for additive manufacturing
- B29C64/393—Data acquisition or data processing for additive manufacturing for controlling or regulating additive manufacturing processes
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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
- B33Y10/00—Processes of additive manufacturing
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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
- B33Y50/00—Data acquisition or data processing for additive manufacturing
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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
- B33Y50/00—Data acquisition or data processing for additive manufacturing
- B33Y50/02—Data acquisition or data processing for additive manufacturing for controlling or regulating additive manufacturing processes
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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
- B33Y70/00—Materials specially adapted for additive manufacturing
- B33Y70/10—Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
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- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
- C09J11/02—Non-macromolecular additives
- C09J11/04—Non-macromolecular additives inorganic
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Abstract
The invention discloses a space framework composite material based on a multi-material 3D printing technology, which belongs to the technical field of composite materials and comprises an internal space framework and an external coating shell, wherein the internal space framework comprises a plurality of same internal space unit structures, each internal space unit structure comprises a plurality of connecting balls and connecting rods, two end points of each connecting rod are respectively connected to two adjacent connecting balls, and the connecting part of each connecting ball and each connecting rod adopts circular arc transition. The invention has unique internal space skeleton structure, better compression resistance, bending resistance and shearing resistance; the combined surface of the rod and the ball adopts circular arc transition, so that better stress distribution performance is achieved; the nano silicon dioxide and the graphene oxide are added in the preparation of the basalt fiber composite material slurry, so that the mechanical property of the composite material can be effectively improved, and the composite material has the functions of sterilization, antistatic property, toughening, water resistance and the like; the 3D printing forming has higher processing forming speed and efficiency and higher precision.
Description
Technical Field
The invention relates to a space framework composite material based on a multi-material 3D printing technology, and belongs to the technical field of composite materials.
Background
The composite material is prepared from fibers such as carbon fibers, glass fibers and aromatic polyester and substrates such as epoxy resin, a metal substrate and a ceramic substrate by a physical or chemical method, has the mechanical characteristics of light weight, high specific strength and specific rigidity and the like compared with metal materials, and is applied to various industries in various fields of actual life. The development of modern science and technology cannot be separated from the development of composite materials, and meanwhile, the development of composite materials also promotes the rapid development of science and technology, thereby playing an important role. The production scale of the composite material is continuously enlarged, and the application range is continuously expanded.
The net-shaped space structure can be used as a way for realizing the light weight of the structure due to the larger specific strength, the larger specific surface area and the excellent impact resistance effect, and can be widely applied to the fields of aerospace, medical treatment, automobile and ship manufacturing. Therefore, the composite material is designed in a net-shaped space structure, so that the composite material product can meet normal use requirements, the lightweight design of the structure can be realized, the material cost can be saved, and the method has important practical significance.
Because the reticular space structure is more complicated, the traditional mould processing mode is difficult to reach the processing and forming requirement, and therefore the 3D printing technology is needed to realize the processing and forming requirement. The 3D printing technology is a process of manufacturing a connecting material into a real object in a mode of stacking 3D model data layer by layer. 3D printing has the advantages of reduced material usage, labor costs and scrap, faster production time, customized freedom and geometric complexity. Unlike the traditional manufacturing industry, the 3D printed product needs to be integrally formed, and each part of the product often needs to take different roles, requiring the use of multiple materials. Therefore, multi-material 3D printing techniques and equipment offer the potential to drive large-scale precision manufacturing in modern industrialization. Multi-material multi-nozzle 3D printing technology that enables fast, continuous, and seamless switching between multiple different printed materials through the use of high-speed pressure valves. The new technology can be applied to a single-nozzle or large-scale multi-nozzle array printing head, and free switching of multiple materials in the 3D printing process is achieved.
The combination of the multi-material 3D printing technology and the composite material can improve the application of the composite material in the traditional production and manufacturing, so that the mechanical property and the physical property of the printed part are more excellent, and the low-cost, high-efficiency, light-weight product design and personalized customization of the design are realized. Therefore, the processing and manufacturing of composite material products are more and more extensive by adopting a multi-material 3D printing mode.
The basalt fiber composite material is one of composite materials with good development potential in modern engineering application. As the basalt fiber composite material has various excellent mechanical properties, the basalt fiber composite material is more and more popular in engineering application. Has been widely applied to the fields of aerospace engineering, vehicle engineering, ocean engineering, construction engineering and the like, and is an important composition material for various spacecrafts, rockets, airplanes, high-speed trains, automobiles, ships, bridges, roads, buildings and the like. Therefore, to popularize the application field and application occasion of the basalt fiber composite material, the internal structure and the forming mode of the basalt fiber composite material must be optimized, and the requirements of social and economic development on high requirements and high standards of the basalt fiber composite material are met and adapted.
The patent with publication number CN113845756A discloses a preparation method of a basalt fiber composite material, which takes basalt fiber as a matrix, and makes multi-walled carbon nanotubes and graphene nanosheets electrophoretically deposited on the basalt fiber by an electrophoretic deposition method to form a conductive network. And coating the surface of the basalt fiber attached with the multi-walled carbon nanotube and the graphene nanosheet with a resin and curing agent mixed solution, and performing die pressing to obtain the basalt fiber composite material. The damage monitoring can be carried out on the prepared basalt fiber composite material more conveniently, and the defect of the material is effectively avoided. On one hand, because the mold structure is relatively simple, the obtained basalt fiber composite material product has a relatively simple structure, cannot prepare a basalt fiber composite material product with a complex space structure, and cannot meet the market diversification requirement. On the other hand, since the compression molding may have defects such as a bad mold filling phenomenon, a burr phenomenon, and a joint line phenomenon, it is difficult to ensure the quality of the basalt fiber composite material finished product.
The patent with publication number CN108339979B discloses a method for preparing a three-dimensional mesh space structure composite material by 3D printing, which comprises the steps of firstly preparing ceramic metal composite powder, performing layer-by-layer printing by 3D printing to form a three-dimensional mesh space metal matrix composite material preform, and then performing printing on a mesh space part in the preform by using pure metal powder to obtain the three-dimensional mesh space structure composite material. However, the composite material with the three-dimensional reticular space structure prepared by the method mainly has the following defects: firstly, the composite material obtained by the preparation method is formed by combining a three-dimensional net-shaped space metal matrix composite material prefabricated body and a metal matrix. The problem of large contact interface exists at the joint of the three-dimensional reticular space metal matrix composite prefabricated body and the metal matrix, and the rigidity and the damping of the contact interface are changed due to the discontinuity of two materials and the mechanical property at the contact interface, so that the dynamic characteristic of the overall structural performance of the composite material is influenced; secondly, the whole three-dimensional reticular space structure composite material prepared by the method is of a cubic structure, and the specific surface area and the space rigidity are small, so that the composite material has weak capability of resisting elastic deformation when the three-dimensional space is stressed. Most importantly, the three-dimensional reticular space structure composite material prepared by the method is in right-angle transition, and the stress concentration problem can be caused. In addition, a plurality of round holes are formed in the surface of the composite material, and the problem of stress concentration also occurs at the circumference of the round holes, particularly the round holes close to the edge.
Patent publication No. CN110128144A discloses a metal and ceramic composite material comprising a ceramic skeleton and a metal matrix. The metal substrate is internally provided with a ceramic framework which is a three-dimensional net structure consisting of a plurality of hollow ceramic balls and a plurality of ceramic rods for connecting the two adjacent hollow ceramic balls. The composite material mainly has the following defects: on one hand, the hollow ceramic ball and the ceramic rod are directly connected without circular arc transition, and due to the fact that the combination of the ball and the rod has geometric mutation, the problem of obvious stress concentration exists, fragile surfaces are easily generated at the combination, and the fatigue safety coefficient of the material is finally weakened; on the other hand, the ceramic ball is of a hollow structure, if the wall thickness of the ceramic ball is too small and the hollow proportion is large, the mechanical property of the ceramic ball is poor, and the ceramic ball is easy to deform. If the wall thickness of the ceramic ball is too large and the hollow ratio is small, material waste is caused. And similarly, the ceramic rod is of a solid structure, and the lightweight design principle of the composite material cannot be met.
The current patents on the preparation and processing of composite materials focus mainly on two aspects: on one hand, the formula of the composite material is optimized and perfected so as to improve the comprehensive mechanical property of the composite material; on the other hand, the composite mode and the internal structure of the composite material are improved, so that the processing and forming efficiency of the composite material and various properties of a composite material formed part are improved. The patent of preparing the basalt fiber composite material product with a complex space structure by taking the basalt fiber green environment-friendly material as a main body is relatively lacked. The unique spatial reticular structure is designed, so that the optimal mechanical property under the condition of light weight can be realized, and the mechanical property of the structural body in the spatial three-dimensional direction can be optimized. Therefore, the composite material is structured in a space network structure, and the use of the composite material can be more effectively utilized. Therefore, the basalt fiber composite material with a unique internal space structure needs to be provided, and then the 3D printing method is combined for forming processing, so as to realize the preparation of the basalt fiber composite material product with a complex space structure, and push the basalt fiber composite material to a wider application field.
Disclosure of Invention
In order to solve the problems, the invention provides a space frame composite material based on a multi-material 3D printing technology. The composite material prepared according to the invention has a unique internal space skeleton structure, and has better compression resistance, bending resistance, shearing resistance and stress distribution compared with the composite material with a common structure. Secondly, the nano silicon dioxide and the graphene oxide are added in the preparation process of the basalt fiber composite material slurry, so that the mechanical property of the composite material can be effectively improved, and special functions such as sterilization, antistatic property, toughening, water resistance and the like can be endowed to the composite material. Finally, the composite material with the internal space skeleton structure is formed in a 3D printing mode, and compared with die forming, the composite material has the advantages of higher machining forming speed and efficiency and higher machining precision.
The invention provides a space framework composite material based on a multi-material 3D printing technology, which comprises an internal space framework and an external coating shell, wherein the internal space framework comprises a plurality of same internal space unit structures, each internal space unit structure comprises a plurality of connecting balls and a connecting rod, two end points of each connecting rod are respectively connected to two adjacent connecting balls, the connecting positions of the connecting balls and the connecting rods adopt circular arc transition, and the circular arc radiuses R of the connecting balls and the connecting rods are respectively equal to the circular arc radiuses R of the connecting balls and the connecting rods1The connecting ball diameter D and the connecting rod diameter D satisfy the following relational expression: r is not more than d1≤D；
The connecting rod in the internal space skeleton is made of basalt fiber composite material, and the connecting ball in the internal space skeleton is made of silicon carbide ceramic composite material; the external cladding shell is made of concrete material, ceramic composite material and ceramic metal composite material;
the connecting ball comprises an inner ball shell, an outer ball shell and a connecting ball internal reinforcing rib, the inner ball shell and the outer ball shell are concentrically arranged, and the inner ball shell and the outer ball shell are fixedly connected through the connecting ball internal reinforcing rib; the internal reinforcing ribs of the connecting ball are symmetrically and uniformly distributed in the center of the ball, the joints of the internal reinforcing ribs of the connecting ball and the inner spherical shell and the outer spherical shell are all in circular arc transition, and the circular arc radius R of the joints of the internal reinforcing ribs of the connecting ball and the inner spherical shell and the outer spherical shell is2And the thickness t of the internal reinforcing rib of the connecting ball1Satisfy the following relation：0.5t1≤R2≤1.5t1；
The connecting rod comprises an inner cylinder, an outer cylinder and a connecting rod internal reinforcing rib; the inner cylinder and the outer cylinder are coaxially arranged and fixedly connected through an internal reinforcing rib of the connecting rod; the connecting rod internal reinforcing ribs are arranged at equal intervals along the central shaft, the joints of the connecting rod internal reinforcing ribs and the inner cylinder and the outer cylinder are in circular arc transition, and the circular arc radius R of the joints of the connecting rod internal reinforcing ribs and the inner cylinder and the outer cylinder is3And the thickness t of the internal reinforcing rib of the connecting rod2Satisfies the following relation: 0.5t2≤R3≤1.5t2。
In one embodiment of the present invention, the basic shape of the internal space cell structure includes a regular cube, a regular tetrahedron, and a regular hexahedron.
In one embodiment of the present invention, the connecting rod is a double-layer hollow cylinder, and the length-diameter ratio is 1: 5; the connecting ball is double-layer hollow spherical shell shape, and the diameter ratio of the connecting rod to the connecting ball is 1: 1.5.
the second purpose of the invention is to provide a preparation method of basalt fiber composite material slurry, which comprises the following steps:
step1, preparing a basalt fiber surface modification solution by using a silane coupling agent, ethanol, a pH regulator, an antistatic agent and water;
step2, adding the chopped basalt fibers into the basalt fiber surface modification solution obtained in the step1, and stirring to obtain a basalt fiber emulsion;
step3, adding the composite material solution into the basalt fiber emulsion obtained in the step2 to obtain basalt fiber composite emulsion;
step4, adding an adhesive and a curing agent into the basalt fiber composite emulsion obtained in the step3, and stirring to obtain basalt fiber composite slurry I;
step5, putting the basalt fiber composite slurry I obtained in the step4 into a planetary ball mill for stirring and grinding to obtain basalt fiber composite slurry II;
step 6, filtering the basalt fiber composite slurry II obtained in the step5 by using a filter screen to obtain basalt fiber composite slurry III;
and 7, loading the basalt fiber composite slurry III obtained in the step 6 into a 3D printing nozzle, and then loading the 3D printing nozzle into a three-dimensional composite configuration direct-writing modeling system for printing.
In one embodiment of the present invention, the composite material solution in step3 includes an inorganic composite material solution and an organic composite material solution; the inorganic composite solution comprises nano-silica; the organic composite solution includes a polyamide.
In an embodiment of the present invention, the adhesive in the step4 is an epoxy resin, and the curing agent is an epoxy resin curing agent.
In an embodiment of the invention, the three-dimensional composite configuration direct writing modeling system in the step 7 comprises two independent printing nozzles, wherein one nozzle is filled with basalt fiber composite slurry, and the other nozzle is filled with silicon carbide ceramic composite slurry.
The third purpose of the present invention is to provide a printing method of a space frame composite material based on a multi-material 3D printing technology, wherein the printing method of the space frame composite material based on the multi-material 3D printing technology comprises the following steps:
step1, establishing a composite material model with a space architecture by using three-dimensional modeling software, and importing an STL file into slicing software for processing after the STL file is generated;
step2, adding a support structure;
step3, setting slicing parameters;
step4, setting printing parameters;
and Step5, post-processing to finally obtain the composite material model with the space architecture.
In one embodiment of the invention, the slicing parameters include layer height, length and width, printing speed and fill rate; the printing parameters comprise the temperature of the spray head, the temperature of the hot bed and the printing speed.
In one embodiment of the invention, the post-processing comprises deburring, polishing, high pressure air cleaning and sand blasting coloring of the printed model.
Advantageous effects
1. The composite material with the space framework provided by the invention has uniform stress distribution and does not have the problem of stress concentration. The internal space framework structure provided by the invention is unique, the internal space framework structure consists of the connecting balls and the connecting rods, the three-dimensional space stress can be borne, the connecting rods are stressed rods and supporting rods in the stress process, the connecting rods and the connecting balls are mutually supported and cooperatively work, and the connecting rods and the connecting balls are in arc transition. Therefore, the stress distribution at the joint surface of each connecting rod and the connecting ball is uniform. Compared with the composite material with the traditional structure, the composite material with the space framework has higher space rigidity, so that the composite material with the structure has better integrity and stronger anti-interference capability. In addition, the composite material with the space framework has larger specific strength and specific surface area, and is superior to the traditional composite material in compression resistance and shear resistance.
2. The composite material with the space framework can better meet the principle of light weight design. The connecting ball is of a double-layer hollow spherical shell structure, the connecting rod is of a double-layer hollow cylindrical structure, and the two structures are symmetrical and stable. On the premise of achieving the required mechanical property, the self-weight of the structure can be minimized, and certain requirements on service life and reliability can be met.
3. The composite material with the space framework has the characteristics of integrity, balance and stability. The composite material with the space framework is internally composed of a plurality of internal space units with the same structure, so that the internal structure of the composite material is more symmetrical and regular, the overall balance and stability of the composite material are improved, the difficulty of 3D printing and forming of the composite material can be reduced, and the printing efficiency is improved.
4. According to the composite material with the space framework, the connecting balls of the internal space units are made of the silicon carbide ceramic matrix composite material, the silicon carbide ceramic matrix composite material has good bonding performance with the basalt fiber composite material, and the strength of the connecting positions can be effectively improved. In addition, the composite material also has the advantages of high temperature resistance, oxidation resistance, abrasion resistance, small density, corrosion resistance and the like, and can improve the overall performance of the composite material.
5. According to the composite material with the space framework, the graphene oxide is added in the process of preparing the basalt fiber composite material slurry, so that the functional groups and the surface roughness of the surface of the basalt fiber can be increased, the interface bonding performance between the basalt fiber and the epoxy resin is improved, and the interlaminar shear strength, the tensile strength and the toughness of the composite material are further improved.
6. According to the composite material with the space framework, the nano silicon dioxide is added in the process of preparing the basalt fiber composite material slurry, so that the surface roughness and lipophilicity of basalt fibers can be improved, the interface compatibility between the basalt fibers and epoxy resin is improved, and the mechanical property of the composite material is enhanced. In addition, the nano silicon dioxide has the characteristics of sterilization, static resistance, ultraviolet radiation resistance, water resistance and the like and can be reserved in the composite material.
7. The composite material with the space framework provided by the invention not only has excellent mechanical properties, but also has the advantages of high temperature resistance, corrosion resistance, light weight and the like, and can be applied to various industrial fields such as aerospace, automobiles, transportation, shipbuilding and the like.
8. The composite material with the space framework is formed in a 3D printing mode, and compared with a traditional die forming and processing mode, the composite material with the space framework has higher processing precision and processing efficiency.
Drawings
FIG. 1 is a flow chart of the preparation of basalt fiber composite slurry according to the present invention;
FIG. 2 is a flow chart of the printing process of the spatial structured composite material based on the multi-material 3D printing technology according to the present invention;
FIG. 3 is a schematic diagram of the structure of the internal unit of the single tetrahedral space;
FIG. 4 is a schematic diagram of a plurality of cube-type internal space skeletons according to the present invention;
FIG. 5 is a schematic view of the arc transition structure of the joint of the connecting ball and the connecting rod of the present invention;
FIG. 6 is a schematic view of the relationship between the arc transition dimensions of the joint of the connecting ball and the connecting rod of the present invention;
FIG. 7 is a schematic structural view of a "honeycomb" type composite material of the present invention;
FIG. 8 is a schematic view of the internal structure of the connecting ball of the present invention;
fig. 9 is a schematic view of the internal structure of the connecting rod of the present invention.
Wherein: 1. a connecting ball; 2. a connecting rod; 3. an outer cladding shell; 11. an outer spherical shell; 12. an inner spherical shell; 13. connecting internal reinforcing ribs of the balls; 21. an outer cylinder of the connecting rod; 22. a connecting rod inner cylinder; 23. inside strengthening rib of connecting rod.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. In which like parts are designated by like reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings. The terms "inner" and "outer" are used to refer to directions toward and away from, respectively, the geometric center of a particular component.
Example 1
The utility model provides a space framework combined material based on many materials 3D printing technique, as shown in fig. 3, fig. 4, fig. 5, fig. 6 and fig. 7, space framework combined material based on many materials 3D printing technique includes inner space skeleton and outside cladding casing 3, inner space skeleton includes a plurality of the same inner space unit structures, every inner space unit structure includes a plurality of connection balls 1 and connecting rod 2, the both ends point of connecting rod 2 is connected respectively on two adjacent connection balls 1, connect ball 1 and connecting rod 2's junction and adopt the circular arc transition, connect the circular arc radius R of ball 1 and connecting rod 2 department1Is connected withBetween the diameter D of the ball receiving 1 and the diameter D of the connecting rod 2, namely the circular arc radius R at the position of the connecting ball 1 and the connecting rod 21The diameter D of the connecting ball 1 and the diameter D of the connecting rod 2 satisfy the following relational expression: r is not more than d1D is less than or equal to D; a plurality of adjacent tie rods 2 enclose the basic shape of the internal space cell structure. The basic shape of the internal space unit structure comprises a regular cube, a regular tetrahedron or a regular hexahedron and the like.
The connecting rod 2 in the internal space skeleton is made of basalt fiber composite material, and the connecting ball 1 in the internal space skeleton is made of silicon carbide ceramic composite material. The material of the external cladding shell 3 can be selected according to specific application and requirements, for example, the concrete material can be applied to the field of buildings; the ceramic composite material can be applied to the fields of precision instruments, aerospace, automobiles and the like; the ceramic-metal composite material can be applied to the fields of large-scale machinery, bridges and the like. The composite material with the space frame is processed and molded in a 3D printing mode. The chopped basalt fibers used in the embodiment have the diameter of 10 microns, the length of 1-10 microns and the length-diameter ratio of 0.1-1.
As shown in fig. 3, 4, 5, 6 and 7, the shape and size of the connecting rod 2 and the connecting ball 1 are the same. The connecting rod 2 is cylindrical, and the length-diameter ratio is 1: 5. the connecting ball 1 is spherical, and the diameter ratio of the connecting rod 2 to the connecting ball 1 is 1: 1.5.
as shown in fig. 8, the connecting ball 1 is a double-layer hollow spherical shell structure, the connecting ball 1 includes an inner spherical shell 12, an outer spherical shell 11 and a connecting ball internal reinforcing rib 13, the inner spherical shell 12 and the outer spherical shell 11 are concentrically arranged, and the inner spherical shell 12 and the outer spherical shell 11 are fixedly connected through the connecting ball internal reinforcing rib 13; the internal reinforcing ribs 13 of the connecting ball are symmetrically and uniformly distributed in the center of the ball, the joints of the internal reinforcing ribs 13 of the connecting ball and the inner spherical shell 12 and the outer spherical shell 11 are all in circular arc transition, and the circular arc radius R of the joints of the internal reinforcing ribs 13 of the connecting ball and the inner spherical shell 12 and the outer spherical shell 11 is2The thickness t of the connecting ball internal reinforcing rib 13 is 0.5 times1And 1.5 times of the thickness t of the connecting ball internal reinforcing rib 131Namely the joint of the internal reinforcing rib 13 of the connecting ball and the inner spherical shell 12 and the outer spherical shell 11Radius of arc R2And thickness t of the connecting ball internal reinforcing rib 131Satisfies the following relation: 0.5t1≤R2≤1.5t1。
As shown in fig. 9, the connecting rod 2 is a double-layer hollow cylindrical structure, and the connecting rod 2 comprises an inner cylinder 22, an outer cylinder 21 and a connecting rod internal reinforcing rib 23; the inner cylinder 22 and the outer cylinder 21 are coaxially arranged, and the inner cylinder 22 and the outer cylinder 21 are fixedly connected through an internal reinforcing rib 23 of the connecting rod; the internal reinforcing ribs 23 of the connecting rod are arranged at equal intervals along the central shaft, the joints of the internal reinforcing ribs 23 of the connecting rod and the inner cylinder 22 and the outer cylinder 21 are in arc transition, and the arc radius R of the joints of the internal reinforcing ribs 23 of the connecting rod and the inner cylinder 22 and the outer cylinder 21 is3Thickness t of the internal reinforcing rib 23 of the connecting rod is 0.5 times2And 1.5 times the thickness t of the internal reinforcing rib 23 of the connecting rod2The radius of the circular arc R between the connecting rod inner reinforcing rib 23 and the connection of the inner cylinder 22 and the outer cylinder 213And the thickness t of the tie rod inner rib 232Satisfies the following relation: 0.5t2≤R3≤1.5t2。
Example 2
As shown in fig. 1, the internal space frame and the external cladding shell both contain basalt fiber composite material, and this embodiment provides a method for preparing basalt fiber composite material slurry, where the preparation of the basalt fiber composite material slurry includes the following steps:
step1, preparing a basalt fiber surface modification solution by using a silane coupling agent, ethanol, a pH regulator, an antistatic agent and water;
step2, adding the chopped basalt fibers into the basalt fiber surface modification solution obtained in the step1, and stirring to obtain a basalt fiber emulsion;
step3, adding the composite material solution into the basalt fiber emulsion obtained in the step2 to obtain basalt fiber composite emulsion;
step4, adding an adhesive and a curing agent into the basalt fiber composite emulsion obtained in the step3, and stirring to obtain basalt fiber composite slurry I;
step5, putting the basalt fiber composite slurry I obtained in the step4 into a planetary ball mill for stirring and grinding to obtain basalt fiber composite slurry II;
step 6, filtering the basalt fiber composite slurry II obtained in the step5 by using a filter screen to obtain basalt fiber composite slurry III;
and 7, loading the basalt fiber composite slurry III obtained in the step 6 into a 3D printing nozzle, and then loading and adding the 3D printing nozzle into a three-dimensional composite configuration direct-writing modeling system to start printing.
The composite material solution in the step3 includes an inorganic composite material solution (such as nano silica) and an organic composite material solution (such as polyamide). In this embodiment, the inorganic composite material solution includes a composite material solution prepared from nano-silica and amic acid, and a composite material solution prepared from graphene oxide and amic acid. The interface bonding performance between the basalt fibers and the epoxy resin can be effectively enhanced, and the interlaminar shear strength of the composite material is improved.
The adhesive in the step4 is epoxy resin, and the curing agent is an epoxy resin curing agent (E-33), wherein the mass ratio of the epoxy resin to the curing agent is 3: 1.
The three-dimensional composite configuration direct-writing modeling system in the step 7 comprises two independent printing nozzles, wherein one nozzle is filled with basalt fiber composite slurry, and the other nozzle is filled with silicon carbide ceramic composite slurry.
Example 3
As shown in fig. 2, the embodiment provides a printing method of a spatial structure composite material based on a multi-material 3D printing technology, including the following steps:
step1, establishing a composite material model with a space architecture by utilizing three-dimensional modeling software such as SolidWorks and 3Dmax, and importing an STL file into slicing software for processing after the STL file is generated;
step2, adding a support structure;
step3, setting slicing parameters;
step4, setting printing parameters;
and Step5, post-processing to finally obtain the composite material model with the space architecture.
As shown in fig. 2, the slicing parameters specifically include layer height, length and width, printing speed, filling rate, and the like. The printing parameters specifically include a nozzle temperature, a hot bed temperature, a printing speed and the like. And the post-processing comprises the processes of deburring, polishing, high-pressure air cleaning, sand blasting, coloring and the like on the printed model.
As shown in fig. 4 and 7, the composite material with the space structure can be processed and molded into a plurality of different structures, such as a cube type, a diamond type, a hexagonal type, etc., by a 3D printing method. And a required space architecture model can be generated through 3D scanning by combining reverse engineering according to the actual requirements of users.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents may be substituted for elements thereof without departing from the scope of the invention.
Claims (10)
1. The utility model provides a space framework combined material based on many materials 3D printing technique, a serial communication port, including inner space skeleton and outside cladding casing, inner space skeleton includes a plurality of the same inner space cell structures, every inner space cell structure includes a plurality of connection balls and connecting rod, the both ends point of connecting rod is connected respectively on two adjacent connection balls, connect the junction adoption circular arc transition of ball and connecting rod, connect the circular arc radius R of ball and connecting rod department1The connecting ball diameter D and the connecting rod diameter D satisfy the following relational expression: r is not more than d1≤D；
The connecting rod in the internal space skeleton is made of basalt fiber composite material, and the connecting ball in the internal space skeleton is made of silicon carbide ceramic composite material; the external cladding shell is made of concrete material, ceramic composite material and ceramic metal composite material;
the connecting ball comprises an inner ball shell, an outer ball shell and a connecting ball internal reinforcing rib, the inner ball shell and the outer ball shell are concentrically arranged, and the inner ball shell and the outer ball shell are fixedly connected through the connecting ball internal reinforcing rib; the internal reinforcing ribs of the connecting ball are symmetrically and uniformly distributed in the center of the ball, the joints of the internal reinforcing ribs of the connecting ball and the inner spherical shell and the outer spherical shell adopt circular arc transition, and the circular arc radius R of the joints of the internal reinforcing ribs of the connecting ball and the inner spherical shell and the outer spherical shell is2And the thickness t of the internal reinforcing rib of the connecting ball1Satisfies the following relation: 0.5t1≤R2≤1.5t1；
The connecting rod comprises an inner cylinder, an outer cylinder and a connecting rod internal reinforcing rib; the inner cylinder and the outer cylinder are coaxially arranged and fixedly connected through an internal reinforcing rib of the connecting rod; the connecting rod internal reinforcing ribs are arranged at equal intervals along the central shaft, the joints of the connecting rod internal reinforcing ribs and the inner cylinder and the outer cylinder are in circular arc transition, and the circular arc radius R of the joints of the connecting rod internal reinforcing ribs and the inner cylinder and the outer cylinder is3And the thickness t of the internal reinforcing rib of the connecting rod2The following relation is satisfied: 0.5t2≤R3≤1.5t2。
2. The multi-material 3D printing technology-based spatial architecture composite material according to claim 1, wherein the basic shape of the internal spatial cell structure comprises regular cubes, regular tetrahedrons, and regular hexahedrons.
3. The spatial framework composite material based on the multi-material 3D printing technology as claimed in claim 2, wherein the connecting rod is a double-layer hollow cylinder with a length-diameter ratio of 1: 5; the connecting ball is double-layer hollow spherical shell shape, and the diameter ratio of the connecting rod to the connecting ball is 1: 1.5.
4. the preparation method of the basalt fiber composite material slurry is characterized by comprising the following steps:
step1, preparing a basalt fiber surface modification solution by using a silane coupling agent, ethanol, a pH regulator, an antistatic agent and water;
step2, adding the chopped basalt fibers into the basalt fiber surface modification solution obtained in the step1, and stirring to obtain a basalt fiber emulsion;
step3, adding the composite material solution into the basalt fiber emulsion obtained in the step2 to obtain basalt fiber composite emulsion;
step4, adding an adhesive and a curing agent into the basalt fiber composite emulsion obtained in the step3, and stirring to obtain basalt fiber composite slurry I;
step5, putting the basalt fiber composite slurry I obtained in the step4 into a planetary ball mill for stirring and grinding to obtain basalt fiber composite slurry II;
step 6, filtering the basalt fiber composite slurry II obtained in the step5 by using a filter screen to obtain basalt fiber composite slurry III;
and 7, loading the basalt fiber composite slurry III obtained in the step 6 into a 3D printing nozzle, and then loading the 3D printing nozzle into a three-dimensional composite configuration direct-writing modeling system for printing.
5. The basalt fiber composite material slurry preparation method according to claim 4, wherein the composite material solution in the step3 includes an inorganic composite material solution and an organic composite material solution; the inorganic composite solution comprises nano-silica; the organic composite solution includes a polyamide.
6. The preparation method of basalt fiber composite material slurry according to claim 4, wherein the adhesive in the step4 is an epoxy resin, and the curing agent is an epoxy resin curing agent.
7. The basalt fiber composite material slurry preparation method according to claim 4, wherein the three-dimensional composite configuration direct writing modeling system in the step 7 comprises two independent printing nozzles, wherein one nozzle is filled with the basalt fiber composite material slurry, and the other nozzle is filled with the silicon carbide ceramic composite material slurry.
8. A printing method of a space frame composite material based on a multi-material 3D printing technology is characterized by comprising the following steps of:
step1, establishing a composite material model with a space architecture by using three-dimensional modeling software, and importing an STL file into slicing software for processing after the STL file is generated;
step2, adding a support structure;
step3, setting slicing parameters;
step4, setting printing parameters;
and Step5, post-processing to finally obtain the composite material model with the space architecture.
9. The method of printing the spatial architecture composite based on the multi-material 3D printing technique according to claim 8, wherein the slicing parameters include layer height, length and width, printing speed and filling rate; the printing parameters comprise the temperature of the spray head, the temperature of the hot bed and the printing speed.
10. The method for printing the spatial structure composite based on the multi-material 3D printing technology according to the claim 8, wherein the post-processing comprises deburring, polishing, high-pressure air cleaning and sand blasting coloring of the printed model.
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