阅读说明：本技术 一种柔性超低密度气凝胶复合材料加工方法 (Processing method of flexible ultra-low density aerogel composite material ) 是由 张丽娟 李健 李文静 黄红岩 苏力军 赵英民 张昊 于 2020-05-25 设计创作，主要内容包括：本发涉及一种柔性构件的加工方法,包括：根据目标柔性构件坯体制备成型工装；利用成型工装制备柔性构件坯体；制备外型面加工工装和内型面加工工装；利用双面胶带将柔性构件坯体贴合在在外型面加工工装的外贴合面上并加工得到半加工坯体；在冷冻室冷却并脱模,获得半加工坯体；利用双面胶带将半加工坯体贴合在在内型面加工工装的内贴合面上并加工；在冷冻室冷却并脱模,获得加工好的柔性构件。本发明还涉及由所述方法制得的柔性构件。本发明可实现大尺寸柔性异型超低密度气凝胶复合材料的加工,获得密度低于28kg/m<Sup>3</Sup>、最大完整尺寸为300mmX300mm,厚度为10mm至30mm,型面和轮廓精度为±0.2mm的柔性构件,其在深空探测领域的热控系统热防护具有重大的应用前景。(The invention relates to a processing method of a flexible member, which comprises the following steps: preparing a forming tool according to a target flexible component blank; preparing a flexible component blank by using a forming tool; preparing an outer profile processing tool and an inner profile processing tool; attaching the flexible member blank to the outer attaching surface of the outer profile surface processing tool by using a double-sided adhesive tape and processing to obtain a semi-processed blank; cooling in a freezing chamber and demoulding to obtain a semi-processed blank; attaching the semi-processed blank body to the inner attaching surface of the inner profile processing tool by using a double-sided adhesive tape and processing; cooling in freezing chamber and demoulding to obtain the finished flexible member. The invention also relates to a flexible member produced by said method. The invention can realize the processing of large-size flexible special-shaped ultra-low density aerogel composite material, and the obtained density is lower than 28kg/m 3 The maximum complete size is 300mmX300mm, the thickness is 10mm to 30mm, the profile and contour accuracy is +/-0.2 mm, and the flexible component has a great application prospect in the thermal protection of a thermal control system in the field of deep space exploration.)

1. A method of manufacturing a flexible member, comprising the steps of:

(1) preparing a forming tool: preparing a forming tool with a corresponding shape and size according to the target shape and the target size of the ultra-low density aerogel composite material flexible member blank;

(2) preparing a flexible member blank: preparing the flexible member blank with a blank outer molded surface and a blank inner molded surface by using the molding tool;

(3) preparing a processing tool: preparing a processing tool, wherein the processing tool comprises an outer profile processing tool with an outer attaching surface capable of attaching to the inner profile of the blank of the flexible member blank and an inner profile processing tool with an inner attaching surface capable of attaching to the outer profile of the product of the flexible member, and positioning blocks are arranged on at least two adjacent edges of the outer profile processing tool and the inner profile processing tool respectively;

(4) processing of the outer profile of the product: bonding a first double-sided adhesive tape on the outer attaching surface of the outer profile processing tool, attaching the inner profile of the flexible member blank to the outer attaching surface of the outer profile processing tool by using the first double-sided adhesive tape, and processing the outer profile of the flexible material member to obtain a semi-processed blank;

(5) demoulding of the outer molded surface machining tool: putting the outer profile machining tool and the semi-machined green body attached to the outer profile machining tool into a freezing chamber and cooling to a first room temperature, and then removing the first double-sided adhesive tape to take the semi-machined green body from the outer profile machining tool;

(6) processing of the inner molded surface of the product: attaching the processed outer profile of the product to the inner attaching surface of the inner profile processing tool through a second double-sided adhesive tape, and processing the inner profile of the product of the flexible material member to obtain a processed flexible member;

(7) demoulding of the inner molded surface processing tool: and putting the inner molded surface processing tool and the processed flexible member attached to the inner molded surface processing tool into a freezing chamber, cooling to a second room temperature, and then removing the second double-sided adhesive tape so as to take the processed flexible member out of the inner molded surface processing tool.

2. The method of claim 1, wherein:

the first and second double-sided adhesive tapes independently have the following properties: the width is 10mm-15 mm; the stripping force is 10N/25 mm-20N/25 mm; the thickness is 0.08mm-0.1 mm;

preferably, the bonding distance of the first double-sided adhesive tape on the outer attaching surface of the outer profile processing tool is 8-10 mm; and/or the bonding distance of the second double-sided adhesive tape on the inner bonding surface of the inner profile processing tool is 8-10 mm;

and the gap between the flexible component blank and the outer profile processing tool and/or the gap between the flexible component blank and the inner profile processing tool after being attached is independently less than 0.05 mm.

3. The method of claim 1, wherein:

the thickness offset of the blank body outer molded surface and the blank body inner molded surface of the flexible component blank is independently 3-5 mm;

the precision of the profile of the external profile of the blank body of the flexible component blank and the profile of the internal profile of the blank body is +/-0.5 mm; and/or

The single-side allowance of the peripheral outline of the flexible component blank body is 20mm-30 mm.

4. The method of claim 1, wherein:

the outer molded surface machining tool and/or the inner molded surface machining tool are/is provided with positioning blocks corresponding to the positions;

preferably, the positioning blocks on the outer profile machining tool and/or the inner profile machining tool are different positioning blocks; more preferably, the number of the positioning blocks is 3-5;

in addition, preferably, the profile precision of the outer profile processing tool and the inner profile processing tool is independent to be +/-0.1 mm.

5. The method of claim 1, wherein:

machining the outer molded surface and the inner molded surface of the blank body according to the theoretical molded surface to the blank body to be machined which is bonded in place;

preferably, the machining of the outer molded surface and the inner molded surface of the blank body is performed by a numerical control machine, and more preferably, the numerical control machine is a three-axis linkage numerical control machine, a four-axis linkage numerical control machine or a five-axis linkage numerical control machine;

it is further preferred that the machining amount of the external blank profile and the internal blank profile of the flexible member blank is independently 3mm-5 mm;

it is further preferred that the machining precision of the external blank profile and the internal blank profile of the flexible member blank is independently ± 0.2 mm.

6. The method of claim 1, wherein:

in the step (4), pre-film-pasting is carried out on the flexible component blank, then the blank inner profile surface of the flexible component blank is pasted on the outer pasting surface of the outer profile surface processing tool, after the positioning is confirmed to be correct, the blank inner profile surface of the flexible component blank is pasted on the outer pasting surface of the outer profile surface processing tool through the first double-sided adhesive tape;

preferably, the pre-pasting mold is pre-pasted from the center of the flexible component blank to two sides.

7. The method of claim 1, wherein:

the first room temperature and the second room temperature are-10 ℃ to 0 ℃, and the freezing time is 40 minutes to 60 minutes.

8. The method of claim 1, wherein:

the flexible member has at least one of the following properties:

the density is less than 28kg/m³；

The maximum full size is 300mm by 300 mm;

the thickness is 10 mm-30 mm; and

the profile and profile accuracy is + -0.2 mm.

9. A flexible member made by the method of any one of claims 1 to 8.

10. Use of the flexible member of claim 9 in the manufacture of a thermal protective material for a thermal control system; more preferably, the thermal control system is a thermal control system used in deep space exploration; it is further preferred that the flexible member is a flat member or a profiled member.

Technical Field

The invention belongs to the field of thermal protection, particularly relates to the technical field of thermal protection materials of a thermal control system used in deep space exploration, and particularly relates to a processing method of a flexible ultralow-density aerogel composite material.

Background

The aerogel material is a novel low-density nano porous material and is the solid material with the best heat insulation performance at present. The aerogel is formed by mutually accumulating nano particles and has a three-dimensional network nano porous structure. The national laboratory of Lorentz Livermol in the United states firstly realizes the technical breakthrough of the preparation of the ultra-low density silicon dioxide aerogel, and the density of the prepared aerogel material can be as low as 3kg/m³. The application of the laboratory technology in the American jet propulsion laboratory in the aerospace field of the ultra-low density aerogel is realized; in 1997, the density of 15-20 kg/m was used in Sojourner, a Mars pathfinder³The silica aerogel is used for preparing the incubator of the core component, so that the purposes of heat preservation and insulation and weight reduction of equipment are achieved; the preparation technology is improved in 1999, and the prepared gradient density is 10-50 kg/m³Aerogel networksA unit for capturing comet matter particles. The flexible ultra-low density aerogel composite material can be used in the field of deep space exploration with extremely strict requirements on heat insulation environment and weight.

However, flexible materials are very difficult to precisely machine, especially flexible ultra low density aerogel composites, and problems of poor dimensions or poor edges often occur after the cutting process, so that the edge or dimensional yield of components made from flexible ultra low density aerogel composites is very low.

CN201710121671.7 discloses a machine tool processing method of a high temperature resistant heat insulation sandwich material member, which comprises the following steps: (1) placing the component material blank in a processing tool; (2) positioning the component material blank by using the positioning features; (3) fixing the positioned component material blank; (4) and carrying out edge cutting processing on the component material blank to obtain an edge cutting processed component. However, this method is only suitable for processing a material in which a flexible core layer is sandwiched between two outer layers, which are hard or brittle, and cannot process a member to be processed made of a flexible ultra-low density aerogel composite material.

CN201710121128.7 discloses a numerical control processing method of a multi-component blank of a high-temperature-resistant heat-insulating sandwich material, which comprises the following steps: (1) placing a single blank material serving as a component material blank in a processing tool, wherein the processing tool is a shape following processing tool serving as a shape following mould; (2) positioning the component material blank by utilizing the positioning characteristics, so that the component material blank is attached and fixed on the shape following processing tool; (3) positioning and aligning on a numerical control machine tool by utilizing a positioning datum plane contained in the conformal machining tool, determining an original point of a coordinate, and fixing; (4) performing edge cutting processing on the component material blank to obtain an edge cutting processed component; (5) further cutting the edge cutting process member into a plurality of the sandwich material members by a dividing process. However, this method is also only suitable for processing a material in which a flexible core layer is sandwiched between two outer layers, which are hard or brittle, and cannot process a member to be processed made of a flexible ultra-low density aerogel composite material, or a member to be processed made of a flexible ultra-low density aerogel composite material.

The ultra-low density aerogel density that the inventor studied is extremely low, possess higher flexibility, can produce the deformation when preparing the body, and material itself can't kick-back under the stress condition, if direct net shaping, size shrinkage profile precision can't satisfy the requirement when the shaping on the one hand, on the other hand material deformation causes the assembly difficulty, consequently, for the profile precision that satisfies heterotypic member, need interior outer profile to leave the machining allowance and carry out the product finish machining, but flexible composite material can't add in the course of working and hold or adsorb fixedly, the processing degree of difficulty is very big. The inventor provides a processing method of a flexible member by deep experiments and combining a large number of theoretical analyses, the method can be used for processing flexible ultra-low density aerogel composite materials, the processing of the special-shaped ultra-low density aerogel composite materials is realized, and the maximum integral size can reach 300mm x300 mm; the thickness is 10 mm-30mm, and the method can be popularized to the processing of other flexible materials.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a processing method of a flexible member in a first aspect, which is characterized by comprising the following steps:

(1) preparing a forming tool: preparing a forming tool with a corresponding shape and size according to the target shape and the target size of the ultra-low density aerogel composite material flexible member blank;

(2) preparing a flexible member blank: preparing the flexible member blank with a blank outer molded surface and a blank inner molded surface by using the molding tool;

(3) preparing a processing tool: preparing a processing tool, wherein the processing tool comprises an outer profile processing tool with an outer attaching surface capable of attaching to the inner profile of the blank of the flexible member blank and an inner profile processing tool with an inner attaching surface capable of attaching to the outer profile of the product of the flexible member, and positioning blocks are arranged on at least two adjacent edges of the outer profile processing tool and the inner profile processing tool respectively;

(4) processing of the outer profile of the product: bonding a first double-sided adhesive tape on the outer attaching surface of the outer profile processing tool, attaching the inner profile of the flexible member blank to the outer attaching surface of the outer profile processing tool by using the first double-sided adhesive tape, and processing the outer profile of the flexible material member to obtain a semi-processed blank;

(5) demoulding of the outer molded surface machining tool: putting the outer profile machining tool and the semi-machined green body attached to the outer profile machining tool into a freezing chamber and cooling to a first room temperature, and then removing the first double-sided adhesive tape to take the semi-machined green body from the outer profile machining tool;

(6) processing of the inner molded surface of the product: attaching the processed outer profile of the product to the inner attaching surface of the inner profile processing tool through a second double-sided adhesive tape, and processing the inner profile of the product of the flexible material member to obtain a processed flexible member;

(7) demoulding of the inner molded surface processing tool: and putting the inner molded surface processing tool and the processed flexible member attached to the inner molded surface processing tool into a freezing chamber, cooling to a second room temperature, and then removing the second double-sided adhesive tape so as to take the processed flexible member out of the inner molded surface processing tool.

The present invention provides, in a second aspect, a flexible member made by the method of the first aspect of the invention.

The present invention provides in a third aspect the use of a flexible member according to the second aspect of the invention in the manufacture of a thermal protective material for a thermal control system; more preferably, the thermal control system is a thermal control system used in deep space exploration; it is further preferred that the flexible member is a flat member or a profiled member.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) the invention can realize the processing of large-size flexible special-shaped ultra-low density aerogel composite material, and the density of the composite material is lower than 28kg/m³The maximum integral size is 300 mm-300 mm, and the thickness is 10 mm-30 mm; the profile and profile accuracy is + -0.2 mm.

(2) The invention can be used for preparing large-size flexible ultra-low density composite material members with various types and specifications, has higher strength and flexibility, and has great application prospect for thermal protection of a thermal control system in the deep space detection field with strict requirements on weight and thermal environment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The present invention provides, in a first aspect, a method of processing a flexible member, characterized by comprising the steps of:

(1) preparing a forming tool: preparing a forming tool with a corresponding shape and size according to the target shape and the target size of the ultra-low density aerogel composite material flexible member blank;

(2) preparing a flexible member blank: preparing the flexible member blank with a blank outer molded surface and a blank inner molded surface by using the molding tool;

(3) preparing a processing tool: preparing a processing tool, wherein the processing tool comprises an outer profile processing tool with an outer attaching surface capable of attaching to the inner profile of the blank of the flexible member blank and an inner profile processing tool with an inner attaching surface capable of attaching to the outer profile of the product of the flexible member, and positioning blocks are arranged on at least two adjacent edges of the outer profile processing tool and the inner profile processing tool respectively;

(4) processing of the outer profile of the product: bonding a first double-sided adhesive tape on the outer attaching surface of the outer profile processing tool, attaching the inner profile of the flexible member blank to the outer attaching surface of the outer profile processing tool by using the first double-sided adhesive tape, and processing the outer profile of the flexible material member to obtain a semi-processed blank;

(5) demoulding of the outer molded surface machining tool: putting the outer profile machining tool and the semi-machined green body attached to the outer profile machining tool into a freezing chamber and cooling to a first room temperature, and then removing the first double-sided adhesive tape to take the semi-machined green body from the outer profile machining tool;

(6) processing of the inner molded surface of the product: attaching the processed outer profile of the product to the inner attaching surface of the inner profile processing tool through a second double-sided adhesive tape, and processing the inner profile of the product of the flexible material member to obtain a processed flexible member;

(7) demoulding of the inner molded surface processing tool: and putting the inner molded surface processing tool and the processed flexible member attached to the inner molded surface processing tool into a freezing chamber, cooling to a second room temperature, and then removing the second double-sided adhesive tape so as to take the processed flexible member out of the inner molded surface processing tool.

The inventor finds that according to the structural characteristics of the special-shaped ultralow-density aerogel composite material, the flexible member blank, particularly the blank made of the special-shaped ultralow-density aerogel composite material, can be processed by adjusting the processing mode, adopting a bonding and fixing mode, demolding at low temperature and the like, and further optimizing the processing of the flexible member blank by adjusting the bonding area, the bonding position and the distance, and ensuring the processing precision.

In some embodiments, the flexible member blank can be made from a flexible ultra-low density aerogel composite, the flexible member being made from the flexible member blank.

In other preferred embodiments, the green body of flexible member has a compressive strength of less than 400Pa (at 10% deformation), such as 300Pa or 200Pa, for example 200 to 350 Pa.

In some preferred embodiments, the first and second double-sided tapes independently have the following properties: a width of 10mm to 15mm (e.g. 11, 12, 13 or 14 mm); a peel force of 10N/25mm to 20N/25mm (e.g., 12, 14, 16, or 18N/25 mm); the thickness is 0.08mm to 0.1mm (e.g., 0.09 mm).

Preferably, the bonding distance of the first double-sided adhesive tape on the outer attaching surface of the outer profile processing tool is 8mm to 10mm (for example, 9 mm). Further or alternatively, the bonding distance of the second double-sided adhesive tape on the inner attaching surface of the inner profile processing tool is 8mm-10mm (for example, 9 mm).

It is further preferred that the gap between the flexible member blank and the outer profile machining tool and/or the inner profile machining tool after attachment is independently less than 0.05mm, for example (0.01 to 0.04mm, such as 0.02 or 0.03 mm).

In other preferred embodiments, the thickness offset of the green body outer profile and the green body inner profile of the green body of the flexible member is independently 3-5mm (e.g., 4 mm).

The precision of the profile of the external profile of the blank body of the flexible component blank and the profile of the internal profile of the blank body is +/-0.5 mm.

It is also preferred that the single margin of the peripheral profile of the flexible member blank is 20mm to 30mm (e.g., 21, 22, 23, 24, 25, 26, 27, 28, or 29 mm).

In further preferred embodiments, the outer profile machining tool and/or the inner profile machining tool have positioning blocks in corresponding positions. Preferably, the positioning blocks on the outer profile machining tool and/or the inner profile machining tool are positioning blocks with different positions. More preferably, the number of positioning blocks is 3-5, such as 4.

In addition, preferably, the profile precision of the outer profile processing tool and the inner profile processing tool is independent to be +/-0.1 mm.

In further preferred embodiments, the machining of the outer and inner blank profiles is carried out according to a theoretical profile for the blank to be machined that is bonded in place.

Preferably, the machining of the outer profile of the blank body and the inner profile of the blank body is performed by a numerical control machine, and more preferably, the numerical control machine is a three-axis linkage numerical control machine, a four-axis linkage numerical control machine or a five-axis linkage numerical control machine.

Additionally or even further preferably, the off-body profile and the in-body profile of the green body of the flexible member are independently machined to be between 3mm and 5mm (e.g., 4 mm).

It is further preferred that the machining precision of the external blank profile and the internal blank profile of the flexible member blank is independently ± 0.2 mm.

In other preferred embodiments, in the step (4), pre-filming is performed on the flexible member blank, then the blank inner profile of the flexible member blank is attached to the outer attachment surface of the outer profile processing tool, and after the positioning is confirmed to be correct, the blank inner profile of the flexible member blank is attached to the outer attachment surface of the outer profile processing tool by using the first double-sided adhesive tape.

Preferably, the pre-pasting mold is pre-pasted from the center of the flexible component blank to two sides.

In other preferred embodiments, the first room temperature and the second room temperature are from-10 ℃ to 0 ℃ (e.g., -5 ℃) and the freezing time is from 40 minutes to 60 minutes (e.g., 50 minutes).

In other preferred embodiments, the flexible member has at least one of the following properties: the density is less than 28kg/m³(ii) a The maximum full size is 300mm by 300 mm; a thickness of 10mm to 30mm (e.g., 20 mm); and the precision of the molded surface is +/-0.2 mm. More preferably, the flexible member has two of said properties, for example said density and maximum full dimension, or said density and thickness, or said density and profile accuracy, or said maximum full dimension and thickness, or said maximum full dimension and profile accuracy, or said thickness and profile accuracy; more preferably, the flexible member has three of the properties, for example, the density, maximum full dimension and thickness, or the density, maximum full dimension and profile accuracy, or the maximum full dimension, thickness and profile accuracy; it is further preferred that the flexible member has all four properties.

In some embodiments, the flexible member may be a regular shaped member or a profiled member, such as an arc, S, L, saddle, etc.

The present invention provides, in a second aspect, a flexible member made by the method of the first aspect of the invention.

The present invention provides in a third aspect the use of a flexible member according to the second aspect of the invention in the manufacture of a thermal protective material for a thermal control system; more preferably, the thermal control system is a thermal control system used in deep space exploration; it is further preferred that the flexible member is a flat member or a profiled member.

According to the invention, the flexible special-shaped surface ultra-low density aerogel composite material is finally obtained through designing, preparing and processing the tooling, pre-die-attaching, machining and die-removing.

The invention provides a method for processing a flexible member, such as a flexible member made of a flexible ultra-low density aerogel composite material, comprising the following steps: designing and preparing a forming tool and a processing tool, processing the forming tool and the processing tool, attaching a die to a product, processing, removing the die, performing post-processing and the like. Wherein, can carry out the design of shaping frock and processing frock according to product body target dimension and shape, can adopt digit control machine tool more than the triaxial for example to carry out the profile processing, paste the moderate double-sided sticky tape of viscosity to the frock surface again, paste body or semi-finished product and make its laminating target in place in making the frock in, it is processed after putting into the lathe benchmark location with it, after the processing is accomplished, in order to guarantee that double-sided sticky tape does not bond the product, put into certain low temperature condition with processingequipment together with the processing component and handle a period, take off the product, finally obtain heterotypic ultra-low density aerogel combined material. The maximum integral size of the aerogel material prepared by the method is 300 mm-300 mm, and the thickness of the aerogel material is 10 mm-30 mm; the density is less than 28kg/m³The processing precision of the molded surface is +/-0.2 mm, and the processing of special components such as cambered surfaces, L-shaped components, saddle-shaped components and the like can be completed. The flexible ultra-low density aerogel composite material prepared by the method provided by the invention is successfully applied to the thermal protection of a deep space detector.