阅读说明：本技术 一种防热-隔热-承载组合式一体化预制体结构及数字化成形工艺 (Heat-proof, heat-insulation and bearing combined type integrated prefabricated body structure and digital forming process ) 是由 单忠德 孙正 吴晓川 张群 刘云志 战丽 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种防热-隔热-承载组合式一体化预制体结构及数字化成形工艺。该结构包括防热层、隔热层以及承载层,层间通过组合式导向套连接。该数字化成形工艺将预制体三维模型采用切片软件沿垂直方向进行分层,提取分层后每一层截面轮廓信息,并对复合材料构件进行有限元分析,确定热量传递与纤维体积分数的关系,计算每一层的层密度,根据每一层层密度规划单层纤维束走向,并确定纤维束铺放路径参数,根据提取的截面轮廓信息以及优化后的纤维束铺放路径、定位板孔径参数以及导向套尺寸参数,加工出符合使用要求的定位板,在定位底板上依次布置组合式导向套,依次进行织造,最后经致密化成型制备防热-隔热-承载组合式一体化复合材料。(The invention discloses a heat-proof, heat-insulation and bearing combined type integrated prefabricated body structure and a digital forming process. The structure comprises a heat-proof layer, a heat-insulating layer and a bearing layer, wherein the layers are connected through a combined guide sleeve. According to the digital forming process, a prefabricated body three-dimensional model is layered in the vertical direction by adopting slice software, profile information of each layered section is extracted, finite element analysis is carried out on a composite material component, the relation between heat transfer and fiber volume fraction is determined, the layer density of each layer is calculated, the trend of a single-layer fiber bundle is planned according to the layer density, the laying path parameter of the fiber bundle is determined, a positioning plate meeting the use requirement is processed according to the extracted section profile information, the optimized laying path of the fiber bundle, the aperture parameter of the positioning plate and the size parameter of a guide sleeve, combined guide sleeves are sequentially arranged on a positioning bottom plate, weaving is sequentially carried out, and finally the heat-proof, heat-insulation and bearing combined type integrated composite material is prepared through densification forming.)

1. The heat-proof, heat-insulating and bearing combined type integrated prefabricated body structure is characterized by comprising a heat-proof layer (1), a heat-insulating layer (2), a bearing layer (3) and a combined type guide sleeve (4) for connecting the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3), wherein the digital forming process comprises the following steps of:

s1: layering the prefabricated body three-dimensional model in the vertical direction by adopting general slicing software, extracting profile information of each layer of cross section after layering the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3), simultaneously carrying out finite element analysis on the composite material component, determining the relation between heat transfer in different directions and fiber volume fraction in the direction, determining the layer density of each layer according to a heat transfer and fiber volume fraction relation model in each direction, planning the trend of each layer of fiber bundles according to the calculated layer density, defining the laying path of the fiber bundles, defining the aperture parameter of a positioning plate and defining the size parameter of a guide sleeve;

s2: processing a positioning plate meeting the use requirement according to the section profile information extracted in the step S1, the optimized fiber bundle laying path, the positioning plate aperture parameter and the guide sleeve size parameter;

s3: according to the three-dimensional model of the prefabricated body and the section profile information extracted by S1, arranging combined guide sleeves (4) of the heat-proof layer (1) on the positioning base plate to form a guide array of the heat-proof layer (1), wherein the surface layers of the guide sleeves (4) of the heat-proof layer (1) are axially provided with matching grooves, the number of the matching grooves on the combined guide sleeves is the same or different, the widths of the matching grooves are the same or different, and the shapes of the matching grooves are the same or different;

s4: using a guide array formed by the combined guide sleeve (4) as a support, weaving fiber bundles along the guide sleeve (4) according to the fiber bundle path optimized in the step S1, fixing the fiber bundles in an engagement groove on the surface of the guide sleeve (4), and performing real-time regulation and control on the tension of the fiber bundles on different paths through a tension sensor (9) and a tension regulation and control device (5), so that each section of the fiber bundles are in different tension states, and weaving the prefabricated body of the heat-proof layer (1) is completed;

s5: according to the three-dimensional model of the prefabricated body and the cross-sectional profile information extracted by S1, on the basis of the guide array of the heat-proof layer (1), the combined guide sleeve arrangement of the heat-insulating layer (2) is carried out to form the guide array of the heat-insulating layer (2), the surface layer of the guide sleeve (4) of the heat-insulating layer (2) is axially provided with the matching grooves, the number of the matching grooves on the combined guide sleeve is the same or different, the widths of the matching grooves are the same or different, and the shapes of the matching grooves are the same or different;

s6: repeating the step S4 to finish weaving the prefabricated body of the heat insulation layer (2);

s7: according to the three-dimensional model of the prefabricated body and the cross-section profile information extracted by S1, on the basis of the guide array of the heat insulation layer (2), the combined guide sleeve arrangement of the bearing layer (3) is carried out to form the guide array of the bearing layer (3), the surface layer of the guide sleeve (4) of the bearing layer (3) is axially provided with the fitting grooves, the number of the fitting grooves on the combined guide sleeve is the same or different, the widths of the fitting grooves are the same or different, and the shapes of the fitting grooves are the same or different;

s8: repeating the step S4 to finish weaving the prefabricated body of the bearing layer (3);

s9: after the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3) are woven, the weaving of the heat-proof-heat-insulating-bearing integrated prefabricated body is completed;

s10: and performing densification molding on the heat-proof, heat-insulation and bearing integrated prefabricated body to prepare the heat-proof, heat-insulation and bearing integrated composite material component.

2. The heat-proof, heat-insulating and load-bearing integrated preform structure and digital forming process as claimed in claim 1, wherein the finite element analysis is performed to determine the relationship between the heat transfer in different directions and the fiber volume fraction in the directions, and the boundary conditions in the finite element analysis are defined according to the actual working conditions of the composite material member, and then the relationship between the heat distribution and the fiber volume fraction in each direction is calculated according to the homogenization theory, so as to distribute the fiber volume fraction in each direction to each layer evenly.

3. The heat-proof, heat-insulating and load-bearing integrated preform structure and digital forming process according to claim 1, wherein the calculated layer density plans the direction of each layer of fiber bundle, firstly extracts node coordinate information of the heat distribution path inside the component according to the heat distribution path information of finite element analysis of claim 2 and a program written by Python, then defines the direction of the fiber bundle in slicing software according to the node coordinate information, and tries to lay the fiber bundle along the heat distribution path to complete the laying design of the fiber bundle path.

4. The structure of the heat-proof, heat-insulation and load-bearing integrated prefabricated body and the digital forming process of the structure of the heat-proof, heat-insulation and load-bearing integrated prefabricated body according to claim 1, wherein the heat-proof layer (1), the heat-insulation layer (2) and the load-bearing layer (3) are connected through the combined guide sleeve (4), so that the layering effect of components in the forming of the prefabricated body and after impregnation can be effectively reduced, and the integrated forming of the multi-structure prefabricated body is realized.

5. The heat-proof, heat-insulation and load-bearing integrated prefabricated body structure and the digital forming process as claimed in claim 1, wherein the heat-proof layer (1), the heat-insulation layer (2) and the load-bearing layer (3) are made of one or more of carbon fiber, silicon carbide fiber, quartz fiber, basalt fiber and aramid fiber, and the selected matrix material is one or more of resin, carbon and ceramic.

6. The heat-proof, heat-insulating and load-bearing integrated prefabricated body structure and the digital forming process according to claim 1, wherein the combined type guide sleeve (4) is made of one or more of fiber reinforced carbon-based or ceramic-based composite materials, metal and pure resin, the guide sleeve (4) can be one or more of a hollow tube, a semi-hollow tube and a solid rod, and the cross section of the guide sleeve (4) is in a shape of one or more of saw tooth, rectangle, semicircle and wave.

7. The heat-proof, heat-insulating and load-bearing integrated preform structure and digital forming process as claimed in claim 1, wherein the tension adjusting device is installed between the knitting needle and the fiber drum, the tension of the yarn during the conveying process is measured by the tension sensor, and the measured tension is compared with a set value to adjust in real time, so that the fiber bundle is always in a tensioned state.

8. The integrated heat-insulating and load-bearing prefabricated body structure and the digital forming process thereof according to claim 1, wherein the combined guide sleeve can be combined in one or more of threaded connection, bonding, riveting and plugging.

Technical Field

The invention relates to the field of composite materials, in particular to a heat-proof, heat-insulation and bearing combined type integrated prefabricated body structure and a digital forming process, which are used for the field of heat-proof, heat-insulation and bearing integrated heat protection of composite materials.

Background

The continuous fiber reinforced composite material has the characteristics of high specific strength, high specific stiffness, excellent thermal stability, strong designability and the like, and is widely applied to the fields of aerospace, transportation and the like. The fiber reinforced carbon-based and ceramic-based composite material has the advantages of high temperature resistance, impact resistance and the like, and becomes a preferred material for high-temperature structural members in the field of aviation, such as thermal protection systems of various aircrafts.

With the continuous improvement of the fields of aerospace, transportation and the like on the requirement of light weight and the development towards multifunctional integration, the future aircraft thermal protection system is developing towards the multifunctional integration of heat prevention, heat insulation and bearing, and then higher requirements are put forward on the preform forming process. At present, the preparation process and the structural characteristics of the prefabricated body are limited, so that the prefabricated body with a multilayer structure is difficult to integrally form, and meanwhile, the impregnated composite material member has poor delamination resistance and becomes the bottleneck of the integral forming of the composite material member of the thermal protection system.

Aiming at the problem that the integrated forming of the prefabricated body with the multilayer structure is difficult, the integrated integral forming of the heat-proof, heat-insulation and load-bearing multilayer prefabricated body is a problem which needs to be solved urgently.

Disclosure of Invention

The invention provides a heat-proof, heat-insulation and bearing combined type integrated prefabricated body structure and a digital forming process, aiming at solving the problems, realizing the heat-proof, heat-insulation and bearing integration of typical components in the field of heat protection, further improving the performance of a heat protection system and reducing the weight of a composite material component.

The invention adopts the following technical scheme:

the utility model provides a heat protection-thermal-insulated-bear combination formula integration preform structure and digital shaping technology, integration preform structure includes heat protection layer (1), insulating layer (2), bearer layer (3) and connects combination formula uide bushing (4) of heat protection layer (1), insulating layer (2), bearer layer (3), and the digital shaping technology step of integration preform includes:

s1: layering the prefabricated body three-dimensional model in the vertical direction by adopting general slicing software, extracting profile information of each layer of cross section after layering the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3), simultaneously carrying out finite element analysis on the composite material component, determining the relation between heat transfer in different directions and fiber volume fraction in the direction, determining the layer density of each layer according to a heat transfer and fiber volume fraction relation model in each direction, planning the trend of each layer of fiber bundles according to the calculated layer density, defining the laying path of the fiber bundles, defining the aperture parameter of a positioning plate and defining the size parameter of a guide sleeve;

s2: processing a positioning plate meeting the use requirement according to the section profile information extracted in the step S1, the optimized fiber bundle laying path, the positioning plate aperture parameter and the guide sleeve size parameter;

s3: according to the three-dimensional model of the prefabricated body and the section profile information extracted by S1, arranging combined guide sleeves (4) of the heat-proof layer (1) on the positioning base plate to form a guide array of the heat-proof layer (1), wherein the surface layers of the guide sleeves (4) of the heat-proof layer (1) are axially provided with matching grooves, the number of the matching grooves on the combined guide sleeves is the same or different, the widths of the matching grooves are the same or different, and the shapes of the matching grooves are the same or different;

s4: using a guide array formed by the combined guide sleeve (4) as a support, weaving fiber bundles along the guide sleeve (4) according to the fiber bundle path optimized in the step S1, fixing the fiber bundles in an engagement groove on the surface of the guide sleeve (4), and performing real-time regulation and control on the tension of the fiber bundles on different paths through a tension sensor (9) and a tension regulation and control device (5), so that each section of the fiber bundles are in different tension states, and weaving the prefabricated body of the heat-proof layer (1) is completed;

s5: according to the three-dimensional model of the prefabricated body and the section profile information extracted by S1, on the basis of the guide array of the heat-proof layer (1), the combined guide sleeve arrangement of the heat-insulating layer (2) is carried out to form the guide array of the heat-insulating layer (2), the surface layer of the guide sleeve (4) of the heat-insulating layer (2) is axially provided with the fitting grooves, the number of the fitting grooves on the combined guide sleeve is the same or different, the widths of the fitting grooves are the same or different, and the shapes of the fitting grooves are the same or different;

s6: repeating the step S4 to finish weaving the prefabricated body of the heat insulation layer (2);

s7: according to the three-dimensional model of the prefabricated body and the section profile information extracted by S1, on the basis of the guide array of the heat insulation layer (2), carrying out combined guide sleeve arrangement on the bearing layer (3) to form the guide array of the bearing layer (3), wherein the surface layer of the guide sleeve (4) of the bearing layer (3) is axially provided with the fitting grooves, the number of the fitting grooves on the combined guide sleeve is the same or different, the widths of the fitting grooves are the same or different, and the shapes of the fitting grooves are the same or different;

s8: repeating the step S4 to finish weaving the prefabricated body of the bearing layer (3);

s9: after the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3) are woven, the weaving of the heat-proof-heat-insulating-bearing integrated prefabricated body is completed;

s10: and performing densification molding on the heat-proof, heat-insulation and bearing integrated prefabricated body to prepare the heat-proof, heat-insulation and bearing integrated composite material component.

Furthermore, by finite element analysis and determining the relationship between the heat transfer in different directions and the fiber volume fraction in the directions, the boundary conditions in the finite element analysis are defined according to the actual use condition of the composite material component, the relationship between the heat distribution and the fiber volume fraction in each direction is calculated according to the homogenization theory, and the fiber volume fraction in each direction is evenly distributed to each layer.

And further planning the direction of each layer of fiber bundles according to the calculated layer density, firstly extracting node coordinate information of the heat distribution path in the component by adopting a program written by Python according to the heat distribution path information of finite element analysis, then defining the direction of the fiber bundles in slice software according to the node coordinate information, and enabling the fiber bundle laying path to follow the heat distribution path as much as possible to finish the laying design of the fiber bundle path.

Furthermore, the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3) are connected through the combined guide sleeve (4), so that the layering effect of the member during and after the preform is formed can be effectively reduced, and the integral forming of the multi-structure preform is realized.

Furthermore, the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3) are made of one or more of carbon fiber, silicon carbide fiber, quartz fiber, basalt fiber and aramid fiber, and the selected matrix material is one or more of resin, carbon and ceramic.

Furthermore, the material of the combined type guide sleeve (4) is one or more of fiber reinforced carbon base or ceramic matrix composite, metal and pure resin, the guide sleeve (4) can be one or more of a hollow tube, a semi-hollow tube and a solid rod, and the cross section of the guide sleeve (4) is in a shape of one or more of saw tooth, rectangle, semicircle and wave.

Furthermore, a tension regulating device is arranged between the knitting needle and the fiber roller, the tension of the yarn in the conveying process is measured through a tension sensor, and then the tension is compared with a set value to be regulated in real time, so that the fiber bundle is always in a tension state.

Further, the combined guide sleeve can be combined in one or more of threaded connection, bonding, riveting and plugging.

The invention has the following advantages:

1. according to the invention, firstly, layering is carried out along a certain direction according to the three-dimensional model of the component, weaving is carried out according to the profile information of the section of the layer, the dimension reduction weaving of the prefabricated body is realized, and the process difficulty is reduced.

2. The fiber bundle laying path of the invention plays the performances of different types of fibers to the maximum extent along the heat transfer direction in the component.

3. The heat-proof layer, the heat-insulating layer and the bearing layer are formed by winding along the combined guide sleeve, the combined guide sleeve can be connected by one or more of thread connection, bonding, riveting and splicing, the multi-structure and multi-material prefabricated body can be integrally formed, and the layered effect of the impregnated composite material component can be effectively reduced.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification

The illustrative embodiments and their description are provided to illustrate the invention and should not be construed as limiting the invention. In the drawings:

FIG. 1 shows a schematic view of a heat protection-insulation-load bearing combined monolithic preform structure;

FIG. 2 shows a schematic view of a modular guide sleeve;

FIG. 3 shows a schematic view of a modular guide sleeve connection;

FIG. 4 shows a schematic diagram of a tension real-time regulation system;

FIG. 5 shows a schematic view of the fiber weaving process along the mating structure guide sleeve;

FIG. 6 shows a schematic view of a composite material of a thermal-protective, thermal-insulating, and load-bearing-fit integrated preform after carburization impregnation.

Reference numerals

The method comprises the following steps of 1-heat-proof layer, 2-heat-insulating layer, 3-bearing layer, 4-combined guide sleeve, 5-tension force regulating device, 6-heat-proof-heat-insulating-bearing integrated prefabricated body, 7-bottom plate, 8-fiber tension meter, 9-fiber bundle and 10-weaving needle.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The invention will be described in detail below with reference to the accompanying drawings and examples.

According to an exemplary embodiment of the present invention, a multi-structure preform to be prepared is shown in FIG. 1. First, a guide sleeve with a fitting structure as shown in fig. 2 is prepared, in the embodiment, the combined guide sleeve is a solid cylinder, and the fiber bundles are wound along fitting grooves of different guide sleeves which are positioned on the same horizontal plane.

According to the embodiment of the invention, the combined guide sleeves are made of aluminum alloy, and the guide sleeves with different sizes are bonded into a whole through AB glue, as shown in figure 3.

According to the embodiment of the invention, the tension is regulated and controlled in real time as shown in figure 3, the tension adjusting device is shown as 3, whether the tension value of the fiber bundle (9) in the weaving process is in a set interval is judged through a control program according to the tension value measured in a fiber tension meter (8), if the measured value is in the set interval, the tension adjusting device (5) is kept still, and if the tension measured value is not in the set interval, the tension adjusting device (5) moves along the vertical fiber direction or the parallel fiber direction, so that the tension value of the fiber bundle is adjusted to be in the set interval.

According to the embodiment of the invention, the heat-proof layer (1), the heat-insulating layer (2) and the bearing layer (3) are respectively woven after the path information planning of the fiber bundles is completed, the weaving process is shown in fig. 4, the weaving needle (10) carries the fiber bundles to weave along the space between two fitting grooves of adjacent guide sleeves, wherein the diameter of each guide sleeve is 4mm, the diameter of each fitting cylinder is 6mm, and the center distance between the two adjacent guide sleeves is 20 mm. The fitting guide sleeve (4) is fixed on the bottom plate (7).

According to the embodiment of the invention, the fibers of the heat-proof layer (1) are silicon carbide fibers, the fibers of the heat-insulating layer (2) are quartz fibers, and the fibers of the bearing layer (3) are carbon fibers.

After weaving all layers, a multi-structure and multi-material joggle joint preform as shown in fig. 1 is prepared, and a continuous fiber reinforced carbon-based composite material (6) is prepared through carburizing treatment, as shown in fig. 5.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.