CN114274544A - Method for preparing composite material reflector by adopting variable curvature mould - Google Patents

Abstract

A method for preparing a composite material reflector using a variable curvature mold, comprising the following steps: obtaining a variable curvature composite material mold; coating a release agent on the variable curvature composite material mold; On the variable-curvature composite material mold, the composite material layup is located above the release agent; and the composite material layup is coated. It can reduce the number of mold preparations and shorten the mold preparation time, improve the versatility of the mold, and reduce the cost of mold preparation.

Description

A method for preparing composite reflector using variable curvature mold

technical field

The invention belongs to the technical field of optical element preparation, and particularly relates to a preparation method of a composite material reflecting mirror.

Background technique

Composite materials are one of the main substrates for mirror fabrication due to their high specific stiffness, strong designability, and good corrosion resistance. At present, the preparation of composite reflection is usually obtained by imprinting and replicating the high-precision surface of the mold, and the parameters such as the curvature and aperture of the mirror surface correspond to the mold one-to-one. The preparation of mirrors with different parameters requires different molds. The specifications and models of the mirrors are complex, and a large number of molds are required. At the same time, high-precision molds have a long processing cycle and high processing costs.

SUMMARY OF THE INVENTION

In view of the above problems, a method is proposed to prepare a composite material mold with variable curvature first, and then adjust the curvature of the composite material mold to obtain the corresponding curvature of the mirror to be prepared.

The invention provides a method for preparing a composite material reflector by using a variable curvature mold, comprising the following steps:

Obtain variable curvature composite molds;

coating a mold release agent on the variable curvature composite mold;

affixing a composite material layup on the variable curvature composite material mold, the composite material layup being located above the release agent;

Coating the composite layup.

According to some embodiments, the obtaining a variable curvature composite mold includes: preparing an invariable curvature mold; preparing a primary variable curvature composite mold based on the invariable curvature mold; changing the primary variable curvature composite mold surface curvature to obtain variable curvature composite molds.

According to some embodiments, the preparation of the invariable curvature mold includes: based on the curvature of the composite material mirror to be prepared, determining the radius of curvature and the aperture for preparing the variable curvature composite material mold to prepare the invariable curvature mold.

According to some embodiments, the invariable curvature mold is machined using indium steel, optical glass, or glass-ceramic as a substrate.

According to some embodiments, preparing a primary variable-curvature composite mold based on the invariable curvature mold includes: laying a prepreg on the invariable-curvature mold according to a layup design, and preparing the primary variable-curvature mold Curvature composite molds.

According to some embodiments, wherein the changing the surface curvature of the primary variable curvature composite mold to obtain the variable curvature composite mold comprises: installing a driving device on the back of the primary variable curvature composite mold, and adjusting the driving The driving force of the device achieves the primary variable curvature mold curvature change.

According to some embodiments, the method further includes: after preparing the primary variable-curvature composite mold based on the invariable-curvature mold, detecting the surface shape of the primary variable-curvature composite mold to ensure that the surface shape accuracy meets the requirements to be Specular accuracy requirements for making composite mirrors; and/or,

After changing the surface curvature of the primary variable-curvature composite mold to obtain the variable-curvature composite mold, the surface shape accuracy of the variable-curvature composite mold is detected to ensure that the surface shape accuracy conforms to the reflection of the composite material to be prepared Mirror surface type accuracy requirements.

According to some embodiments, the applying the composite material layup on the variable curvature composite material mold, the composite material layup being over the release agent, comprises: applying the prepreg according to the layup design The composite material mirror blank is prepared by curing and molding on the variable curvature composite material mold.

According to some embodiments, the layup design is obtained according to the technical requirements of the material mirror parameters to be fabricated.

According to some embodiments, the method further includes: adjusting the surface shape of the mirror blank until it meets the surface shape requirements by adjusting the curvature of the variable curvature composite mold and/or the manufacturing process.

The present invention can achieve the following technical effects:

The invention realizes reducing the number of mold preparations and shortening the mold preparation time through the variable curvature mold, improves the versatility of the mold, and reduces the cost of mold preparation.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

Fig. 1 is the schematic flow chart of the preparation of composite material reflector according to the embodiment of the present invention;

FIG. 2 is a schematic flowchart of step 101 of the method shown in FIG. 1 according to an embodiment of the present invention;

3 is a schematic diagram of an invariable curvature composite mold and a primary variable curvature composite mold according to an embodiment of the present invention;

4 is a schematic diagram of pneumatic driving of a variable curvature composite mold according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a mirror blank of a variable curvature composite mold mirror according to an embodiment of the present invention.

Detailed ways

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections It should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

Spatially relative terms such as "below", "below", "lower", "below", "above", "above", etc. may be used herein for convenience Description is used to describe the relationship of one element or feature to another element or feature as illustrated in the figures. It will be understood that these spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" or "beneath" other elements or features would then be oriented "under the other elements or features" above the characteristics". Thus, the exemplary terms "under" and "under" can encompass both an orientation of above and below. Terms such as "before" or "before" and "after" or "followed by" may similarly be used, for example, to indicate the order in which light travels through elements. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. In addition, it will also be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will be further understood that the terms "comprising" and/or "comprising" when used in this specification designate the presence of stated features, integers, steps, operations, elements and/or parts, but do not exclude one or more The presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof, of other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items, and the phrase "at least one of A and B" means A only, B only, or both A and B.

It will be understood that when an element or layer is referred to as being "on," "connected to," "coupled to," or "adjacent to another element or layer" When present, it may be directly on, directly connected to, directly coupled to, or directly adjacent to another element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly connected to," "directly coupled to," "directly adjacent to" another element or layer , with no intervening elements or layers present. However, in no case should "on" or "directly on" be interpreted as requiring a layer to completely cover the layer below.

Embodiments of the invention are described herein with reference to schematic illustrations (and intermediate structures) of idealized embodiments of the invention. As such, variations to the shapes of the illustrations are to be expected, eg, as a result of manufacturing techniques and/or tolerances. Accordingly, embodiments of the present invention should not be construed as limited to the particular shapes of the regions illustrated herein, but are to include deviations in shapes due, for example, to manufacturing. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be construed to have meanings consistent with their meanings in the relevant art and/or the context of this specification, and will not be idealized or overly interpreted in a formal sense, unless expressly defined as such herein.

The present invention provides a method for preparing a composite material reflector using a variable curvature mold, as shown in FIG. 1 , comprising the following steps:

S101, obtaining a variable curvature composite material mold;

S102, coating a release agent on the variable curvature composite material mold;

S103, sticking a composite material layup on the variable curvature composite material mold, and the composite material layup is located above the release agent;

S104, coating the composite material layer.

Since the surface curvature of the variable-curvature mold can be changed, the manufacturing requirements for mirrors with different curvatures can be realized by changing the curvature of the surface of the variable-curvature mold without changing the mold, thereby reducing the number of molds to be prepared and shortening the mold. Preparation time, improve the versatility of the mold, reduce the cost of mold preparation.

Although in some scenarios, the curvature of the composite material mirror to be prepared has a corresponding variable curvature composite material mold, the composite material mirror to be prepared can be produced by the preparation method shown in Figure 1, however, In other application scenarios, if there is no corresponding variable curvature composite mold, the variable curvature composite mold needs to be installed first.

Corresponding to these application scenarios, according to some embodiments, the step S101, obtaining a variable curvature composite material mold, as shown in FIG. 2, includes:

S1011, preparing an invariable curvature mold;

S1012, based on the invariable curvature mold, prepare a primary variable curvature composite material mold;

S1013, changing the surface curvature of the primary variable-curvature composite material mold to obtain a variable-curvature composite material mold.

According to some embodiments, S1011, the preparation of the invariable curvature mold includes: based on the curvature of the composite material mirror to be prepared, determining the radius of curvature and aperture for preparing the variable curvature composite material mold to prepare the invariable curvature mold.

Illustratively, indium steel, optical glass, or glass-ceramic is used as a substrate to machine the invariable curvature mold.

According to some embodiments, S1012, the preparing a primary variable-curvature composite material mold based on the invariable curvature mold includes: laying a prepreg on an invariable-curvature mold according to a layup design, and preparing the primary Variable curvature composite mold.

According to some embodiments, S1013, the changing the surface curvature of the primary variable-curvature composite material mold to obtain the variable-curvature composite material mold includes: installing a driving device on the back of the primary variable-curvature composite material mold, and adjusting the driving The driving force of the device achieves the primary variable curvature mold curvature change.

According to some embodiments, the method further includes: after preparing the primary variable-curvature composite mold based on the invariable-curvature mold, detecting the surface shape of the primary variable-curvature composite mold to ensure that the surface shape accuracy meets the requirements to be Specular accuracy requirements for making composite mirrors; and/or,

After changing the surface curvature of the primary variable-curvature composite mold to obtain the variable-curvature composite mold, the surface shape accuracy of the variable-curvature composite mold is detected to ensure that the surface shape accuracy conforms to the reflection of the composite material to be prepared Mirror surface type accuracy requirements.

According to some embodiments, the applying the composite material layup on the variable curvature composite material mold, the composite material layup being over the release agent, comprises: applying the prepreg according to the layup design The composite material mirror blank is prepared by curing and molding on the variable curvature composite material mold.

Exemplarily, the design of the layup is obtained according to the technical requirements of the material to be prepared and the parameters of the mirror.

According to some embodiments, the method further includes: adjusting the surface shape of the mirror blank until it meets the surface shape requirements by adjusting the curvature of the variable curvature composite mold and/or the manufacturing process.

In order to facilitate understanding, the foregoing embodiments are combined into the following embodiments for description. It should be noted that the steps and material processes in the following description are for the purpose of explaining clearly and as detailed as possible, and do not constitute a closed description of the embodiments. , materials and processes are not necessarily included in other embodiments of the present invention.

In one embodiment, by S1011, an invariable curvature mold is prepared;

Wherein, based on the curvature of the composite material mirror to be prepared, the shape technical parameters such as the curvature radius and diameter of the composite material mold with variable curvature are determined, and indium steel or optical glass is used as the base material to process and prepare the invariable curvature mold.

Continue to pass S1012, based on the invariable curvature mold, prepare a primary variable curvature composite material mold;

Among them, according to the technical parameter requirements of the variable curvature composite material mold, the optimization of the composite material lay-up design is completed, and the prepreg is laid on the non-variable curvature mold according to the lay-up design, and the vacuum bag process or other composite material molding process is adopted. A primary variable curvature composite mold was prepared.

Continue through S1013, changing the surface curvature of the primary variable curvature composite material mold to obtain a variable curvature composite material mold;

Among them, the high-precision surface profile of the variable-curvature composite material mold is detected by an interferometer, and the surface profile accuracy must be superior to the requirements of the mirror surface profile of the composite material mirror to be processed. A driving device is installed on the back of the variable-curvature composite material mold, such as Air pressure drive or support ring drive, etc., as the power mechanism for adjusting the curvature, adjust the driving ability of the drive device to realize the change of the curvature of the variable curvature mold, meet the design requirements and detect the surface shape accuracy under different curvatures, all of which must meet the surface shape accuracy. The precision requirements for the mirror surface of the composite material to be prepared.

Wherein, the prepared variable curvature composite material mold is adjusted to the curvature of the composite material mirror to be prepared and the surface shape is detected.

After obtaining the variable-curvature composite material mold, the step of preparing the composite material mirror can be started. Therefore, next, perform S102, and apply a release agent on the variable-curvature composite material mold;

Continue to perform S103: paste the composite material layup on the variable curvature composite material mold, and the composite material layup is located above the release agent;

Among them, according to the technical requirements of the parameters of the composite material mirror to be prepared, the optimization of the composite material layup design is completed, and the prepreg is laid on the variable curvature composite material mold according to the layup design, and the composite material mirror mirror blank is prepared by curing and molding. , and detect the surface shape, if it does not meet the requirements, according to the interferometer test results, adjust the variable curvature composite material mold and preparation process, etc., until it meets the surface shape requirements.

After obtaining the mirror blank that meets the surface shape requirements, in order to form the "reflection" function of the mirror, it is necessary to continue to perform S104: coating the composite material layer.

Among them, the prepared composite material mirror blank is coated with a film, and the final inspection is carried out.

The manufacturing method of the present invention for manufacturing a composite material reflector by using a variable curvature mold has been described above, and the embodiments of the present invention will be further described below with reference to FIGS. 3 to 5 .

In one embodiment, the required parameters of the mirror to be installed are as follows: the effective aperture to be prepared is 50 mm (considering the edge effect, the mirror aperture is prepared at 60 mm), the radius of curvature is 100 mm, the thickness is 4 mm, and the reflection of concave carbon fiber composite materials applied to long-wave infrared mirror.

Based on the aforementioned preparation method, the preparation steps are exemplarily listed as follows:

S1011, preparing an invariable curvature mold. Wherein, based on the curvature of the composite material mirror to be prepared, the shape technical parameters such as the radius of curvature and the diameter of the composite material mold with variable curvature are determined, and the base material is processed and prepared into a mold with constant curvature.

Specifically, the effective diameter of the composite material mirror to be prepared is 50 mm and the curvature is 100 mm, and the basic parameters of the invariable curvature mold for preparing the variable curvature composite material mold are determined as the diameter of 60 mm, the radius of curvature of 100 mm, and the thickness of 20 mm.

Considering the edge effect of composite materials, that is, composite materials often have edges, therefore, the diameter is set to 50mm+10mm, 60mm, and according to the specific stiffness and thermal expansion coefficient of the mold material, the diameter-thickness ratio is selected to be 3~5:1. The diameter is 60mm, then the thickness is 20mm~12mm, so as to meet the requirement that the pressure deformation during the heating and composite material forming process is smaller than the surface shape accuracy.

Illustratively, invariable curvature molds are fabricated using indium steel, optical glass, or glass-ceramic as substrates.

Considering the application scenario, as shown in FIG. 3 , the base material is processed and prepared into a concave invariable curvature mold 320 . In order to ensure the mold accuracy, the surface shape accuracy of the processed mold needs to be detected.

Exemplarily, the surface shape accuracy is related to the application scenario of the mirror, and the surface shape accuracy of the invariable curvature mold is better than 1/40λ. The surface accuracy is better than 1/40λ, that is, 265nm.

S1012, based on the invariable curvature mold, prepare a primary variable curvature composite material mold;

Among them, according to the technical parameter requirements of the variable curvature composite material mold, the optimization of the composite material lay-up design is completed, and the prepreg is laid on the non-variable curvature mold according to the lay-up design, and the vacuum bag process or other composite material molding process is adopted. A variable curvature composite mold was prepared.

Exemplarily, as shown in Figure 3, based on the classical laminate theory and technical parameters such as the variable curvature mold radius of 100mm, the diameter of 60mm, and the thickness of 2mm, the layup design of the variable curvature composite mold is completed [0 90 45 -45] 3s, lay it on the surface of the invariable curvature mold according to the layup design, use the vacuum bag process to prepare the convex primary variable curvature mold mirror blank 310, and test its surface accuracy, which is better than 1/35λ (λ=10.6μm ), for example 302nm, otherwise, if the surface shape accuracy does not meet the requirements, repeat S1012 until the surface shape accuracy requirements are met.

Illustratively, the composite material prepreg may be M40, T300, T600, T700 or T800.

Illustratively, the primary composite mold 310 is prepared using a vacuum bagging process, an RTM process, or a compression molding process.

S1013, changing the surface curvature of the primary variable-curvature composite material mold to obtain a variable-curvature composite material mold.

As shown in Fig. 4, the annular aerodynamic deformation shell is bonded to the back of the variable curvature mold mirror blank, and the air volume between the back of the variable curvature mold and the annular aerodynamic deformation shell is controlled through the air inlet 430, and the resulting air pressure changes The curvature radius of the convex variable curvature mold can be changed. For example, the variation range of the curvature radius is between 95mm and 110mm. The surface shape detected by the long-wave infrared interferometer must be better than 1/35λ (λ=10.6μm), such as 302nm, Otherwise, repeat S1012 and S1013 until the requirements are met.

Continue to adjust the air pressure to keep the pressure at 1 atmosphere to make the curvature radius of the convex variable curvature mold 410 100mm, and check its surface shape, which must be better than 1/35λ (λ=10.6μm), and apply mold release agent on its high-precision surface for use.

Next, according to the requirements of an effective diameter of 50 mm, a radius of curvature of 100 mm, and a thickness of 4 mm to be prepared, based on the classical laminate theory, the layup is determined to be [0 90 45 -45] 6s, and it is laid on the convex variable curvature mold according to the layup design. The surface of 510 is cured at room temperature, and the mirror blank 540 to be prepared is prepared. The detection surface type must be better than 1/30λ (λ=10.6 μm).

Next, the mirror blank with a diameter of 60mm, a radius of curvature of 100mm, and a thickness of 4mm is coated with a reflective film, and a long-wave infrared interferometer is used to detect the surface shape. The surface shape accuracy is better than 1/30λ (λ=10.6μm). Qualified to complete the preparation of the mirror.

On the basis of the completion of the previous embodiment, the next mirror preparation requirements are: the effective diameter to be prepared is 50mm (considering the edge effect, the mirror diameter is prepared at 60mm), the radius of curvature is 105mm, and the thickness is 6mm. Concave carbon fiber applied to long-wave infrared Composite mirrors.

Considering that the variable curvature composite mirror mold has been prepared, as shown in Figure 4, for this preparation requirement, it is only necessary to adjust the curvature radius of the convex variable curvature mold shown in Figure 4 to 105mm by changing the air pressure , the ply can be changed to [0 90 45 -45] 9s, and the rest can be done according to the corresponding steps, which will not be repeated here.

The radius of the variable-curvature composite mirror mold is changed from 100mm in the previous use to the current 105mm, and the preparation of the mirror is completed. In this process, there is no need to prepare a new mirror mold, and the mold used in the previous use is directly used. Change the radius of curvature to get a new mirror mold.

It can be seen that, since the surface curvature of the variable curvature mold can be changed, for the production requirements of mirrors with different curvatures, it can be achieved by changing the curvature of the surface of the variable curvature mold without changing the mold, thereby reducing the number of mold preparations. Quantity and shorten the mold preparation time, improve the versatility of the mold, and reduce the cost of mold preparation.

Exemplarily, the variation range of the surface curvature of the variable curvature mold mentioned in the present disclosure is 95 mm to 110 mm, and as long as the curvature of the mirror to be prepared is within the aforementioned range, there is no need to replace the mold.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other.

Although the embodiments of the present invention have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present invention. Embodiments are subject to variations, modifications, substitutions and variations.

The above specific embodiments of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made according to the technical concept of the present invention shall be included in the protection scope of the claims of the present invention.

Claims (10)

1. a method that adopts variable curvature mould to prepare composite material mirror, it is characterized in that, described method comprises the steps: Obtain variable curvature composite molds; coating a mold release agent on the variable curvature composite mold; affixing a composite material layup on the variable curvature composite material mold, the composite material layup being located above the release agent; The composite layup is coated. 2. The method for preparing a composite material mirror using a variable curvature mold according to claim 1, wherein the obtaining of the variable curvature composite material mold comprises: Preparation of invariable curvature molds; Based on the invariable curvature mold, preparing a primary variable curvature composite mold; The surface curvature of the primary variable curvature composite mold is varied to obtain a variable curvature composite mold. 3. The method for preparing a composite material mirror using a variable curvature mold according to claim 2, wherein the preparation of the invariable curvature mold comprises: Based on the curvature of the composite material mirror to be prepared, determine the radius of curvature and aperture for preparing the variable curvature composite material mold to prepare the invariable curvature mold. 4 . The method for preparing a composite material reflector using a variable curvature mold according to claim 2 , wherein the invariable curvature mold is processed by using indium steel, optical glass or glass-ceramic as a base material. 5 . 5. The method for preparing a composite material mirror using a variable curvature mold according to claim 2, wherein, based on the invariable curvature mold, preparing a primary variable curvature composite material mold, comprising: The primary variable-curvature composite material mold is prepared by laying the prepreg on the invariable-curvature mold according to the lay-up design. 6. The method for preparing a composite material reflector using a variable curvature mold according to claim 2, wherein said changing the surface curvature of the primary variable curvature composite material mold to obtain a variable curvature composite material mold, include: A driving device is installed on the back of the primary variable-curvature composite mold, and the driving force of the driving device is adjusted to change the curvature of the primary variable-curvature mold. 7. The method for preparing a composite material reflector using a variable curvature mold according to claim 2, further comprising: After the primary variable curvature composite mold is prepared based on the invariable curvature mold, the surface shape of the primary variable curvature composite mold is detected to ensure that the surface shape accuracy conforms to the mirror surface of the composite reflector to be prepared. type accuracy requirements; and/or, After changing the surface curvature of the primary variable-curvature composite mold to obtain a variable-curvature composite mold, the surface shape accuracy of the variable-curvature composite mold is detected to ensure that the surface shape accuracy conforms to the reflection of the composite material to be prepared Mirror surface type accuracy requirements. 8. The method for preparing a composite material reflector using a variable curvature mold according to claim 1, wherein the composite material layup is attached to the variable curvature composite material mold, and the composite material layup is located at the Above the release agent, including: According to the layup design, the prepreg is laid on the variable curvature composite material mold, and the composite material mirror blank is prepared by curing and molding. 9 . The method for preparing a composite material reflector by using a variable curvature mold according to claim 8 , wherein the lay-up design is obtained according to the technical requirements for the parameters of the material reflector to be prepared. 10 . 10. The method for preparing a composite material mirror using a variable curvature mold according to claim 8 or 9, further comprising: By adjusting the curvature of the variable curvature composite mold and/or the manufacturing process, the surface shape of the mirror blank is adjusted until it meets the surface shape requirements.

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