A novel hybrid machining method and apparatus based on ion beam additive and subtractive technologies

Abstract

The application provides a novel composite machining method and equipment based on ion beam additive and subtractive technology, first, the assembly and layout of a workpiece and a tooling are completed according to a preset machining condition; second, sputtering particles are generated by ion source bombardment of a sputtering target, the sputtering particle beam is shaped and corrected through a specially-made deposition function correction plate, and real-time closed-loop regulation and control is realized in cooperation with an optical thickness monitoring system to accurately level and repair the surface of the workpiece; finally, the machining station is switched, the surface of the workpiece is directly bombarded by an ion beam, and the workpiece is cooperatively machined in combination with a subtractive process. The application obtains a Gaussian-like deposition beam by shaping the deposition function correction plate, accurately fills local pits of an optical workpiece and smooths high-frequency fluctuations on the surface, real-time regulation and control are realized in cooperation with the optical thickness monitoring system, the workpiece base material does not need to be removed as a whole, the defect trimming time is greatly shortened, and material loss is reduced; meanwhile, the surface quality and machining efficiency of the optical element are effectively improved through cooperative machining in combination with the subtractive process, and the surface shape error is quickly converged.

Description

Technical Field

[0001] This invention relates to the field of ion beam processing, and more specifically to a novel composite processing method and equipment based on ion beam additive and subtractive manufacturing technology. Background Technology

[0002] Space optical imaging systems are increasingly widely used in various detection fields. With the development of science and technology, modern optical systems have increasingly higher requirements for the surface shape accuracy and surface roughness of optical components. Fast, accurate, and inexpensive processing methods are a perpetual pursuit. Existing optical mirror processing methods have many problems. First, for local pits in mirrors, traditional processing methods such as small grinding heads and stress disks must remove the entire layer to achieve the purpose of removing local pits. This process is often very long and has extremely low cost-effectiveness. Second, mid-to-high frequency errors are an important factor restricting the final manufacturing accuracy of large-aperture optical components. Traditional methods for handling mid-to-high frequency errors often use large-diameter grinding disks for mid-to-high frequency smoothing, which can suppress mid-to-high frequency errors to a certain extent. However, for large-aperture mirrors, the increase in grinding disk size leads to increased difficulty in process stability control and iteration of removal. The smoothing processing cycle is long, and due to process instability, new mid-to-high frequency errors are introduced, which can easily form a vicious cycle where errors are difficult to converge. Summary of the Invention

[0003] To address the problems of existing technologies, the present invention aims to provide a novel composite processing method and equipment based on ion beam additive and subtractive manufacturing technology. First, a correction plate is manufactured by reverse engineering and the deposition function and area are controlled to cover surface depressions and surface shape errors such as mid-to-high frequency. Then, subtractive processing is used to modify the shape, which greatly improves the overall processing efficiency and meets the requirements of cost-effectiveness in optical processing.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] On the one hand, this invention provides a novel composite processing method based on ion beam additive and subtractive manufacturing technology, comprising:

[0006] S1. Workpiece and tooling assembly: Complete the workpiece clamping and corresponding tooling assembly and layout according to the preset processing conditions.

[0007] S2. Ion beam sputtering additive leveling: Sputtering particles are generated by bombarding the sputtering target with an ion source. The sputtering particle beam is shaped and corrected by a deposition function correction plate. Combined with real-time closed-loop control by an optical thickness monitoring system, the workpiece surface is precisely leveled and repaired.

[0008] S3. Ion beam direct bombardment subtractive material removal: Switch the processing station and remove the additive manufacturing tooling. The workpiece surface is directly bombarded by an ion beam, and the overall material removal of the workpiece is completed by utilizing the ion etching effect.

[0009] Furthermore, the correction principle of the deposition function correction plate is as follows:

[0010] The deposition function correction plate has precision holes. The size of the holes, the spacing between the holes, and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function, so that the surface of the correction plate forms a zoned differentiated particle transmittance distribution. It can shape and constrain the disordered sputtering particle beam generated by the ion beam bombardment of the sputtering target, so that the sputtering particles penetrating the correction plate form a high-precision, well-ordered deposition beam that matches the Gaussian-type target deposition function, and deposit it in a specific recessed area or the entire workpiece.

[0011] Furthermore, step S1 specifically involves: clamping the workpiece to be processed onto a horizontal workpiece stage, and assembling a deposition function correction plate between the sputtering target and the workpiece processing surface.

[0012] Furthermore, step S2 specifically includes: according to the different workpieces being processed, the sputtering target 2 rotates and adjusts the target material; the ion source emits an ion beam to bombard the sputtering target, generating a beam of sputtered atomic and molecular particles; after the particle beam is shaped by the deposition function correction plate, it forms a standard Gaussian deposition beam, which is selectively deposited on the local concave areas of the workpiece or the overall surface of the workpiece, filling the micro-pits of the workpiece and smoothing the high-frequency morphology of the workpiece surface; during the processing, the optical thickness monitoring system collects the deposition rate on the workpiece surface in real time, dynamically adjusts the spatial position of the correction plate or the working parameters of the ion source, and stabilizes the output shape of the deposition function.

[0013] Furthermore, step S3 specifically includes: removing all additive manufacturing fixtures such as sputtering targets and deposition function correction plates inside the optical path, fixing the workpiece with the help of a vertical workpiece stage; starting the ion source so that the ion beam directly and vertically bombards the workpiece surface without obstruction, and uniformly removing the workpiece surface material by relying on the ion etching effect to complete the overall subtractive shaping of the workpiece.

[0014] Furthermore, the preparation steps of the deposition function correction plate are as follows:

[0015] Step a: Deploy the Faraday cup array and measure the raw sputtered particle spatial distribution data without a deposition function correction plate;

[0016] Step b: Combining the preset Gaussian-type target deposition function with the measured original distribution data, the particle transmittance distribution in each region of the correction plate is inverted and solved, and the pore arrangement parameters are determined by pore size modulation or pore density modulation.

[0017] Step c: Based on the determined hole arrangement parameters, a laser precision drilling process is used to process and shape the correction plate substrate to obtain a deposition function correction plate that matches the requirements of Gaussian deposition.

[0018] A novel composite processing equipment based on ion beam additive and subtractive manufacturing technology, applied to the aforementioned novel composite processing method based on ion beam additive and subtractive manufacturing technology, includes a horizontal workpiece stage, a deposition function correction plate, a vertical workpiece stage, an ion source, and a sputtering target. The deposition function correction plate is horizontally disposed on the upper side of the horizontal workpiece stage. The vertical workpiece stage and the ion source are respectively installed on the left and right sides of the deposition function correction plate. The sputtering target is installed between the vertical workpiece stage and the ion source and is rotatable.

[0019] Furthermore, the deposition function correction plate has precision holes, and the size of the holes, the spacing between the holes, and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function.

[0020] The beneficial effects of this invention are as follows:

[0021] This invention obtains a Gaussian-like deposition beam by shaping the deposition function correction plate, which can accurately fill local pits in optical workpieces and smooth high-frequency undulations on the surface. Combined with the optical thickness monitoring system for real-time control, the deposition effect is stable. It does not require the overall removal of the workpiece substrate material, which greatly shortens the defect repair time and reduces material loss. At the same time, combined with the ion beam subtractive processing, it can quickly converge surface shape errors and effectively improve the surface quality and overall processing efficiency of optical components. Attached Figure Description

[0022] Figure 1 This is a logic flowchart of the processing method of the present invention;

[0023] Figure 2 This is a schematic diagram of the fabrication process of the deposition function correction plate;

[0024] Figure 3 This is an assembly diagram of the processing equipment of the present invention.

[0025] Figure label:

[0026] 1. Vertical workpiece stage; 2. Sputtering target; 3. Ion source; 4. Deposition function correction plate; 5. Horizontal workpiece stage. Detailed Implementation

[0027] In the description of this embodiment, it should be noted that the terms "upper", "lower", "center", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of the invention is usually placed in when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0029] On the one hand, this invention provides a novel composite processing method based on ion beam additive and subtractive manufacturing technology, such as... Figure 1 As shown, it includes:

[0030] S1. Workpiece and tooling assembly: Complete the workpiece clamping and corresponding tooling assembly and layout according to the preset processing conditions.

[0031] S2, Ion beam sputtering additive leveling: Sputtering particles are generated by bombarding sputtering target 2 with ion source 3. The sputtering particle beam is shaped and corrected by deposition function correction plate 4. In conjunction with optical thickness monitoring system, real-time closed-loop control is used to accurately level and repair the workpiece surface.

[0032] S3. Ion beam direct bombardment subtractive material removal: Switch the processing station and remove the additive manufacturing tooling. The workpiece surface is directly bombarded by an ion beam, and the overall material removal of the workpiece is completed by utilizing the ion etching effect.

[0033] The key to the above method lies in the deposition function correction plate 4. The correction principle of the deposition function correction plate 4 is as follows:

[0034] The deposition function correction plate 4 has precision holes on its plate body. The size of the holes, the spacing between the holes and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function, so that the plate surface forms a zoned differentiated particle transmittance distribution. It can shape and constrain the disordered sputtering particle beam generated by the ion beam bombardment of the sputtering target 2, so that the sputtering particles penetrating the correction plate form a high-precision, well-ordered deposition beam that matches the Gaussian-type target deposition function, and deposit it in a specific recessed area or the entire workpiece.

[0035] In addition, step S1 specifically involves: clamping the workpiece to be processed on the horizontal workpiece stage 5, and assembling the deposition function correction plate 4 between the sputtering target 2 and the workpiece processing surface; the sputtering target 2 as a whole can rotate.

[0036] Step S2 specifically includes: depending on the different workpieces being processed, the sputtering target 2 is rotated and the target material is adjusted; the ion source 3 emits an ion beam to bombard the sputtering target 2, generating a beam of sputtered atomic and molecular particles; after being shaped by the deposition function correction plate 4, the particle beam forms a standard Gaussian deposition beam, which is selectively deposited on the local concave areas of the workpiece or the entire surface of the workpiece, filling the micro-pits of the workpiece and smoothing the high-frequency morphology of the workpiece surface; during the processing, the optical thickness monitoring system collects the deposition rate on the workpiece surface in real time, dynamically adjusts the spatial position of the correction plate or the working parameters of the ion source 3, and stabilizes the output morphology of the deposition function.

[0037] Step S3 specifically includes: removing all additive manufacturing fixtures such as the sputtering target 2 and the deposition function correction plate 4 inside the optical path, fixing the workpiece with the support of the vertical workpiece stage 1; starting the ion source 3 so that the ion beam can directly and vertically bombard the workpiece surface without obstruction, and uniformly removing the workpiece surface material by relying on the ion etching effect to complete the overall subtractive shaping of the workpiece.

[0038] It should be noted that, as Figure 2 As shown, the preparation steps of the deposition function correction plate 4 are as follows:

[0039] Step a: Deploy the Faraday cup array and measure the original sputtered particle spatial distribution data without the deposition function correction plate 4;

[0040] Step b: Combining the preset Gaussian-type target deposition function with the measured original distribution data, the particle transmittance distribution in each region of the correction plate is inverted and solved, and the pore arrangement parameters are determined by pore size modulation or pore density modulation.

[0041] Step c: Based on the determined hole arrangement parameters, laser precision drilling technology is used to process and shape the correction plate substrate to obtain the deposition function correction plate 4 that matches the requirements of Gaussian deposition.

[0042] On the other hand, the present invention provides a novel composite processing equipment based on ion beam additive and subtractive manufacturing technology, which is applied to the aforementioned novel composite processing method based on ion beam additive and subtractive manufacturing technology, such as... Figure 3 As shown, it includes a horizontal workpiece stage 5, a deposition function correction plate 4, a vertical workpiece stage 1, an ion source 3, and a sputtering target 2. The deposition function correction plate 4 is horizontally arranged on the upper side of the horizontal workpiece stage 5. The vertical workpiece stage 1 and the ion source 3 are respectively installed on the left and right sides of the deposition function correction plate 4. The sputtering target 2 is installed between the vertical workpiece stage 1 and the ion source 3 and the sputtering target 2 can rotate.

[0043] In addition, the deposition function correction plate 4 has precision holes, and the size of the holes, the spacing between the holes and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function.

[0044] Based on the composite processing method of ion beam additive and subtractive manufacturing, local additive manufacturing is used to fill in the pits in localized concave areas, "replacing subtraction with addition" to reduce processing allowance. In mid-to-high frequency surface areas that are difficult to handle with traditional subtractive manufacturing, additive technology is used to cover the uneven areas of the surface to make the surface smooth, reducing the difficulty of removing mid-to-high frequency errors. Combined with high deterministic removal methods, ultra-smooth processing is achieved. This "combination of addition and subtraction" improves the final manufacturing accuracy and surface convergence efficiency of the mirror.

[0045] Although embodiments of the present invention have been described in the specification, these embodiments are merely illustrative and should not be construed as limiting the scope of protection of the present invention. Various omissions, substitutions, and modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A novel composite processing method based on ion beam additive and subtractive manufacturing technology, characterized in that, include: S1. Workpiece and tooling assembly: Complete the workpiece clamping and corresponding tooling assembly and layout according to the preset processing conditions. S2. Ion beam sputtering additive leveling: Sputtering particles are generated by bombarding the sputtering target with an ion source. The sputtering particle beam is shaped and corrected by a deposition function correction plate. Combined with real-time closed-loop control by an optical thickness monitoring system, the workpiece surface is precisely leveled and repaired. S3. Ion beam direct bombardment subtractive material removal: Switch the processing station and remove the additive manufacturing tooling. The workpiece surface is directly bombarded by an ion beam, and the overall material removal of the workpiece is completed by utilizing the ion etching effect.

2. The novel composite processing method based on ion beam additive and subtractive manufacturing technology as described in claim 1, characterized in that, The correction principle of the deposition function correction plate is as follows: The deposition function correction plate has precision holes. The size of the holes, the spacing between the holes, and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function, so that the surface of the correction plate forms a zoned differentiated particle transmittance distribution. It can shape and constrain the disordered sputtering particle beam generated by the ion beam bombardment of the sputtering target, so that the sputtering particles penetrating the correction plate form a high-precision, well-ordered deposition beam that matches the Gaussian-type target deposition function, and deposit it in a specific recessed area or the entire workpiece.

3. The novel composite processing method based on ion beam additive and subtractive manufacturing technology as described in claim 1, characterized in that, Step S1 specifically involves: clamping the workpiece to be processed on a horizontal workpiece stage, and assembling a deposition function correction plate between the sputtering target and the workpiece processing surface.

4. The novel composite processing method based on ion beam additive and subtractive manufacturing technology as described in claim 1, characterized in that, Step S2 specifically includes: adjusting the sputtering target by rotating it according to the different workpieces being processed; the ion source emitting an ion beam to bombard the sputtering target, generating a beam of sputtered atomic and molecular particles; the particle beam is shaped by the deposition function correction plate to form a standard Gaussian deposition beam, which is selectively deposited on local depressions or the entire surface of the workpiece, filling micro-pits and smoothing the high-frequency morphology of the workpiece surface; during the processing, the optical thickness monitoring system collects the deposition rate on the workpiece surface in real time, dynamically adjusts the spatial position of the correction plate or the working parameters of the ion source, and stabilizes the output shape of the deposition function.

5. A novel composite processing method based on ion beam additive and subtractive manufacturing technology as described in claim 1, characterized in that, Step S3 specifically includes: removing all additive manufacturing fixtures such as sputtering targets and deposition function correction plates inside the optical path, fixing the workpiece with the help of a vertical workpiece stage; starting the ion source so that the ion beam can directly and vertically bombard the workpiece surface without obstruction, and uniformly removing the workpiece surface material by relying on the ion etching effect to complete the overall subtractive shaping of the workpiece.

6. A novel composite processing method based on ion beam additive and subtractive manufacturing technology as described in claim 1, characterized in that, The preparation steps of the deposition function correction plate are as follows: Step a: Deploy the Faraday cup array and measure the raw sputtered particle spatial distribution data without a deposition function correction plate; Step b: Combining the preset Gaussian-type target deposition function with the measured original distribution data, the particle transmittance distribution in each region of the correction plate is inverted and solved, and the pore arrangement parameters are determined by pore size modulation or pore density modulation. Step c: Based on the determined hole arrangement parameters, a laser precision drilling process is used to process and shape the correction plate substrate to obtain a deposition function correction plate that matches the requirements of Gaussian deposition.

7. A novel composite processing equipment based on ion beam additive-subtractive manufacturing technology, applied to the novel composite processing method based on ion beam additive-subtractive manufacturing technology as described in any one of claims 1-6, characterized in that, The device includes a horizontal workpiece stage, a deposition function correction plate, a vertical workpiece stage, an ion source, and a sputtering target. The deposition function correction plate is horizontally positioned above the horizontal workpiece stage. The vertical workpiece stage and the ion source are respectively installed on the left and right sides of the deposition function correction plate. The sputtering target is installed between the vertical workpiece stage and the ion source and is rotatable.

8. A novel composite processing equipment based on ion beam additive and subtractive manufacturing technology as described in claim 7, characterized in that, The deposition function correction plate has precision holes, and the size of the holes, the spacing between the holes, and the array arrangement are all designed according to the differentiated design of the Gaussian-type target deposition function.

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