A texture-based method for precise size control of thin plate chemical milling

Abstract

The present invention relates to the field of surface processing technology, and in particular to a texture-based method for precise dimensional control of chemical milling of thin plates. The method comprises the following steps: establishing a chemical milling rate-crystallographic orientation mapping relationship, calculating the chemical milling rate for the closest-packed surface, determining the texture type of the thin plate raw material and the volume fraction of each texture type; calculating the minimum angle between the crystal plane normal and the closest-packed surface for different texture types; calculating the chemical milling rate, and calculating the chemical milling time parameter based on the chemical milling depth. This method enables precise control of chemical milling dimensions.

Description

Technical Field

[0001] The present invention relates to the technical field of surface processing, and in particular to a method for precise control of the size of chemical milling of a thin plate based on texture. Background Art

[0002] Chemical milling involves exposing the metal component to be machined to a chemical etching solution. Compared to mirror milling, it offers advantages such as minimal deformation, high production efficiency, strong adaptability, and reduced stress. It continues to play an irreplaceable role in the manufacturing of thin-plate aircraft parts. To further meet the demands of lightweight aircraft design and precise assembly, the structural dimensions of chemically milled thin-plate parts require even higher precision control. The key control parameter is the milling rate, which is a key parameter to be controlled under a specific composition, concentration, and temperature of the chemical milling solution. However, the raw materials used for typical aircraft thin-plate components (including aluminum alloys, titanium alloys, and steel), influenced by the production and rolling processes, typically contain varying amounts and types of texture. Even with the same material grade and thickness, the types and amounts of texture can vary between manufacturers. Due to the varying interfacial energies associated with different crystallographic orientations, chemical milling rates vary with texture orientation. Conventional methods for controlling chemical milling rates fail to account for the influence of sheet texture. Using only milling rates derived from methods such as weighing, they are applied to all sheet thicknesses and manufacturers, making it difficult to achieve precise control of the chemically milled dimensions of thin-plate components. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention proposes a method for precise control of the size of chemical milling of thin plates based on texture, which can achieve precise control of the chemical milling size.

[0004] The present invention is achieved by adopting the following technical solutions:

[0005] A method for precise dimensional control of thin plate chemical milling based on texture, comprising the following steps:

[0006] Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. :

[0007]

[0008] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle;

[0009] Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction d k ;

[0010] Step S3. Calculate the crystal plane normal under different texture types n k ′ Minimum angle with the closest packed surface i k ;

[0011] Step S4. Calculate milling rate :

[0012]

[0013] Step S5: Calculate the milling time according to the milling depth.

[0014] In step S3, the minimum angle i k The calculation method is:

[0015]

[0016] Where, It is the normal direction of the most closely packed plane in the crystal.

[0017] Each texture type n k ′ / l k ′ Volume fraction d k The calculation method is: obtained according to the orientation distribution function ODF.

[0018] The step S1 specifically includes the following steps:

[0019] Step S 11 . Prepare chemical milling test blocks;

[0020] Step S 12 Determination of crystal orientation and original height of test surfaces in chemically milled test blocks;

[0021] Step S 13 . Test the milling rate;

[0022] Step S 14 . Calculate the milling rate of the densest surface .

[0023] The step S 11 Specifically, it means: selecting raw material plates of the same material, and obtaining chemical milling test blocks through heat treatment; one side of the chemical milling test block is the test surface, and the other side is the non-test surface; the test surface is polished, and the non-test surface is protected with chemical milling glue.

[0024] The step S 12 Determining the crystal orientation of the test surface in the chemical milling test block specifically refers to: determining the texture type and texture orientation of the test surface in the chemical milling test block, and obtaining the grain size of the sample surface. i #Orientation, i =1,…,n.

[0025] The orientation includes the normal direction of the crystal plane of the grain n i and rolling direction l i .

[0026] The step S 12 Determining the original height of the test surface in the milling test block specifically refers to: reconstructing the original test surface and measuring the average height of the original grains in units of grains .

[0027] The step S 14 Specifically refers to: according to the crystal plane normal and the closest packed plane normal in each grain The angle between the crystal plane and the normal is obtained. n i The most densely packed surface with the smallest angle , calculate the milling rate of the most densely packed surface .

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. This invention establishes a relationship between the chemical milling rate and the texture of thin plates cut with chemical milling based on quantitative texture characterization, improving precision to ±0.05mm compared to traditional chemical milling. Furthermore, based on the different texture types and texture contents in plates of varying thicknesses, the chemical milling rate of the densest surface can be quantitatively determined and directly applied to thin plate chemical milling, achieving efficient and precise control of customized chemical milling dimensions.

[0030] 2. In the present invention, polishing the test surface can avoid introducing residual stress into the surface of the chemical milling test block, which would affect the subsequent test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0032] Figure 1 It is a schematic diagram of the process of the present invention;

[0033] Figure 2 Schematic diagram of the texture of the 2024-O aluminum alloy sheet milling test block in the present invention;

[0034] Figure 3 This is the grain structure image of the 2024-O raw material plate in the present invention;

[0035] Figure 4 This is the ODF diagram of the orientation distribution of the 2024-O raw material plate in the present invention;

[0036] Figure 5 Schematic diagram of the texture of the milled test block of 5A02-O aluminum alloy sheet in the present invention;

[0037] Figure 6 This is the grain structure image of the 5A02-O raw material plate in the present invention;

[0038] Figure 7 This is the ODF diagram of the orientation distribution of the 5A02-O raw material plate in the present invention. DETAILED DESCRIPTION

[0039] Example 1

[0040] As a basic embodiment of the present invention, the present invention includes a method for precise size control of chemical milling of thin plates based on texture, comprising the following steps:

[0041] Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. :

[0042]

[0043] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle.

[0044] Step S2. Determine the texture type of the sheet material n k ′ / lk ′ and various texture types n k ′ / l k ′ Volume fraction d k .

[0045] Step S3. Calculate the crystal plane normal under different texture types n k ′ Minimum angle with the closest packed surface i k .

[0046] Step S4. Calculate milling rate :

[0047]

[0048] Step S5: Calculate the milling time parameter according to the milling depth.

[0049] Example 2

[0050] As a preferred embodiment of the present invention, the present invention includes a method for precise size control of thin plate chemical milling based on texture, comprising the following steps:

[0051] Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. :

[0052]

[0053] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle.

[0054] Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction dk .

[0055]

[0056] Where, Texture type n k ′ / l k ′ The volume occupied, V, refers to the total volume of the test sample.

[0057] Step S3. Calculate the crystal plane normal under different texture types n k ′ Minimum angle with the closest packed surface i k :

[0058]

[0059] Where, It is the normal direction of the most closely packed plane in the crystal.

[0060] Step S4. Calculate milling rate :

[0061]

[0062] Step S5: Calculate the milling time parameter according to the milling depth.

[0063] Example 3

[0064] As another preferred embodiment of the present invention, the present invention includes a method for precise control of the size of chemical milling of a thin plate based on texture, comprising the following steps:

[0065] Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. Specifically, the following steps are included:

[0066] Step S 11 Prepare a chemical milling test block. Select raw material plates of the same material and heat treat them to create a chemical milling test block. One side of the chemical milling test block serves as the test surface, while the other side serves as the non-test surface. Polish the test surface, and protect the non-test surface with chemical milling adhesive.

[0067] Step S 12 . Determination of crystal orientation and original height of test surfaces in chemically milled test blocks.

[0068] Step S 13 . Test the milling rate.

[0069] Step S14 . Calculate the milling rate of the densest surface :

[0070]

[0071] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle.

[0072] Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction d k .

[0073] Step S3. Calculate the crystal plane normal under different texture types n k ′ Minimum angle with the closest packed surface i k .

[0074] Step S4. Calculate milling rate :

[0075]

[0076] Step S5: Calculate the milling time parameter according to the milling depth.

[0077] Example 4

[0078] As the best embodiment of the present invention, refer to the attached Figure 1 The present invention includes a method for precise size control of chemical milling of thin plates based on texture, comprising the following steps:

[0079] Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. Specifically, the following steps are included:

[0080] Step S 11. Prepare chemical milling test blocks. Select raw material plates of the same material, and obtain chemical milling test blocks with the largest possible grain size through heat treatment, and the number of grains on the test surface is as small as possible. The materials are aluminum alloy, titanium alloy, and steel sheet with a thickness of 0.6mm≤δ≤5.0mm. Through heat treatment, and try to avoid deformation of the test block. Any one side of the chemical milling test block is used as the test surface, and the other side is used as the non-test surface. Use electrolytic polishing, vibration polishing and other methods to polish the test surface to avoid introducing residual stress into the surface of the chemical milling test block and affecting the subsequent test results. Protect the non-test surface with chemical milling glue.

[0081] Step S 12 . Determine the crystal orientation and original height of the test surface of the chemical milling test block. Determine the texture type and texture orientation of the test surface of the chemical milling test block, and obtain the sample surface grains 1#, 2#, 3#, ..., i #( i =1,…,n), including the grain normal n i and rolling direction l i More specifically, the method used to determine the surface grain orientation is electron backscatter diffraction (EBSD), and the number of grains selected is ≥5, and the orientation difference between different grains is as large as possible (judged by the pole figure orientation), and the grain size is as large as possible.

[0082] The original test surface was reconstructed using AFM and white light interferometer, and the 1#~ i #common n The average height of the original grains .

[0083] Step S 13 Test the milling rate. Configure milling fluids suitable for different raw materials, perform milling after degreasing and cleaning, and set different milling times. t , taking a theoretical plane parallel to the rolling surface as a reference, the surface thickness after milling is measured. i #common n Chemical milling height H of each grain i终 ,time t Inner grain 1#~ i The milling depth of # is recorded as h1=H 1原 -H 1终 , h2=H 2原 -H 2终 , h3=H 3原 -H 3终 ,…,h i =H i原 -H i终 ( i=1,…,n), grain 1#~ i # of milling rate v i =h i / t, for different grain plane normal directions n i If necessary, you can also create a specific milling solution v i - t time relationship.

[0084] Step S 14 Since chemical reactions during milling generally preferentially destroy low-energy crystal planes, which are usually the closest-packed crystal planes, such as {111} of face-centered cubic (fcc), {110} of body-centered cubic (bcc), and {0001} of hexagonal close-packed (hcp). Therefore, it is necessary to calculate the normal direction of the above crystal planes and the normal direction of the closest-packed plane in each grain. Since the most densely packed plane is generally a crystal plane family, including 1, ..., m most densely packed planes, there are a total of m most densely packed plane normals, j =1,…,m. In each grain, the normal direction to the crystal plane can be obtained. n i The most densely packed surface with the smallest angle , to calculate the milling rate of the most densely packed surface The calculation formula is as follows:

[0085]

[0086] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle.

[0087] Step S2. Raw material texture measurement. Determine the texture type of the sheet raw material. n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction d kBefore chemical milling parts, X-ray diffraction (XRD), electron backscatter diffraction (EBSD), neutron diffraction, etc. can be used to determine the surface texture type and texture content of the raw material plate used for the parts. Texture type n k ′ / l k ′ ,in k =1,…,n. The texture type is obtained according to the orientation distribution function ODF. n k ′ / l k ′ Volume fraction d k :

[0088]

[0089] Where, Refers to texture type n k ′ / l k ′ The volume occupied, V, refers to the total volume of the test sample.

[0090] Step S3: Calculation of chemical milling parameters.

[0091] Calculate the crystal plane normal direction under different texture types under the same chemical milling solution as in step S1 n k ′ Minimum angle with the closest packed surface i k :

[0092]

[0093] Where, It is the normal direction of the most closely packed plane in the crystal.

[0094] Then calculate the milling rate :

[0095]

[0096] Finally, the milling time parameters are calculated according to the milling depth.

[0097] In the above steps S1 to S3, the vectors need to be normalized to unit vectors with a modulus of 1 during the calculation process, including the crystal plane normal of the grain. n i , crystal orientation in rolling direction l i , the normal to the most closely packed plane in the crystal As well as the crystal plane normal and rolling direction of the surface texture of the raw material plate used for parts n k ′ / l k ′ .

[0098] Example 5

[0099] As a specific embodiment of the present invention, this example takes a 2024-O aluminum alloy sheet with a thickness of 3.0 mm and no aluminum cladding as an example. Based on this, a method for precise dimensional control of thin sheet chemical milling based on texture is proposed, which includes the following steps:

[0100] Step S1. Establishing a mapping relationship between milling rate and crystallographic orientation. Specifically, the following steps are included:

[0101] Step S 11 Prepare chemical milling test blocks. Prepare 10mm×5mm×3mm test blocks (L×LT×ST), set the heat treatment system: 430 After 10 hours of heat treatment, the chemically milled specimens obtained had grain sizes up to 300µm. One L×LT side of the chemically milled specimen was selected as the test surface, while the other L×LT side was designated as the non-test surface. The test surface was vibratory polished at 7200 rpm, using 200g of oil-based polishing fluid for 180 minutes, avoiding the introduction of stress. The non-test surface was protected with chemical milling adhesive.

[0102] Step S 12 . Determine the crystal orientation and original height of the test surface in the chemical milling test block. Determine the texture type and texture orientation of the test surface of the chemical milling test block, as shown in the attached instructions. Figure 2 According to the polar figure orientation, the grain sizes of the grains on the surface of the sample are selected as 1#, 2#, 3#, 4#, 5#, and 6#, including the normal direction of the grain surface. n i and rolling direction l i , respectively (1 01.1)1 / [0 1 0]1, (1.2 0 2.1)2 / [0 1 0]2, (0 0 1)3 / [1.1 1.2 0]3, (1 1 1)4 / [-1 1 0]4, (21.3 2)5 / [1 0 -1]5, (0 0 1)6 / [1 0 0]6. The original test surface was reconstructed using white light interferometry, and the average height H of the original grains was measured in units of grains. 1原 =2.941, H 2原 = 2.943, H 3原 =2.945, H 4原 =2.940, H 5原=2.943, H 6原 =2.939.

[0103] Step S 13 Test the milling rate and establish a milling rate-crystallographic orientation mapping relationship. Prepare the milling solution: NaOH (200g / L), Al (5g / L), and set the temperature to room temperature. Mill the aluminum alloy after degreasing and cleaning. Set the milling time to t = 10 minutes and measure the surface grain size after milling. 6 #Chemical milling height H 1终 =2.900mm, H 2终 =2.904mm, H 3终 =2.917mm, H 4终 =2.889mm, H 5终 =2.894mm, H 6终 =2.911mm, the milling depth is recorded as h1=H 1原 -H 1终 =0.041mm, h2=H 2原 -H 2终 =0.039mm, h3=H 3原 -H 3终 =0.028mm, h4=H 4原 -H 4终 =0.051mm, h5=H 5原 -H 5终 =0.049mm, h6=H 6原 -H 6终 =0.028mm. Milling rate v 1=h1 / t=0.0041mm / min, v 2=h2 / t=0.0039mm / min, v 3=h3 / t=0.0028mm / min, v 4=h4 / t=0.0051mm / min, v 5=h5 / t=0.0049mm / min, v 6=h6 / t=0.0028mm / min. For different grain normal directions n i , can be established under specific milling solution v i - tSince chemical reactions during milling generally prioritize the destruction of low-energy crystal planes, 2024-O aluminum alloy is mainly composed of fcc parent phase, and the closest-packed crystal planes include (111), (11-1), (1-11), and (-111), such as {111} of face-centered cubic fcc, {110} of body-centered cubic bcc, and {0001} of close-packed hexagonal hcp. Therefore, it is necessary to calculate the normal direction of the above crystal planes and the normal direction of the closest-packed plane in each grain. The angle between the two. Generally, the closest packed plane is a crystal plane family, which contains multiple closest packed planes, defined here as ,in j =1,…,m. The minimum angles between the normal direction of the crystal plane and the closest-packed plane in each grain are 35.3°, 38.0°, 54.7°, 0°, 10.6°, and 54.7°, respectively. The closest-packed planes with the minimum angles between the normal direction of the crystal plane and the grains 1# to 6# are (111) or (1-11), (111) or (1-11), (111) or (1-11) or (-111), (111), (111) or (1-11) or (-111), respectively. The milling rate of the closest-packed plane is calculated. v 密 =0.00495mm / min. The calculation method is as follows:

[0104]

[0105] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, For n i The most densely packed surface with the smallest angle.

[0106] Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction d k Before chemical milling parts, the surface texture type and texture content of the raw material plate used for the parts are determined, as shown in the attached manual. Figure 3As shown, the main textures are brass texture and R texture, which are {110} / <1-12> and {124} / <211> According to the orientation distribution function ODF, as shown in the appendix of the manual Figure 4 As shown, the volume fraction of brass texture {110} / <1-12> is obtained d 1 =81.5%, R texture {124} / <211> Volume fraction d 2 =18.5%.

[0107] Step S3. Calculate the crystal plane normal direction under different texture types using the same milling solution as step S1. n k Minimum angle with the closest packed surface i k , the minimum angle under the two textures i 1 =35.3°, i 2 =28.1°. The calculation method is as follows:

[0108]

[0109] Where, It is the normal direction of the most closely packed plane in the crystal.

[0110] Step S4. Calculate milling rate =0.0041mm / min, the calculation method is as follows:

[0111]

[0112] Step S5. Then, the milling time parameter is calculated according to the milling depth. The thickness accuracy after milling can reach ±0.05mm.

[0113] Traditional milling rate testing methods use a weighing method to calculate the milling rate of 2024-O aluminum sheet at 0.00262 mm / min. Milling time is then calculated based on the milling depth, resulting in a thickness accuracy of only ±0.1 mm. In contrast, this method allows for higher-precision control of milled aluminum sheet dimensions, while also enabling personalized precision control for sheet materials with different texture types.

[0114] Example 6

[0115] As another specific embodiment of the present invention, this example takes a 5A02-O aluminum alloy sheet with a thickness of 2.0 mm as an example. Based on this, a method for precise dimensional control of thin sheet chemical milling based on texture is proposed, which includes the following steps:

[0116] Step S1. Establishing a mapping relationship between milling rate and crystallographic orientation. Specifically, the following steps are included:

[0117] Step S 11 Prepare chemical milling test blocks. Prepare 10mm×5mm×2mm test blocks (L×LT×ST), set the heat treatment system: 450 After 10 hours of heat treatment, the chemically milled specimens obtained had grain sizes up to 100µm. One L×LT side of the chemically milled specimen was selected as the test surface, while the other L×LT side was designated as the non-test surface. The test surface was vibrated and polished at 7200 rpm with 200g of oil-based polishing fluid for 180 minutes, avoiding the introduction of stress. The non-test surface was protected with chemical milling adhesive.

[0118] Step S 12 . Determine the crystal orientation and original height of the test surface in the chemical milling test block. Determine the texture type and texture orientation of the test surface of the chemical milling test block, as shown in the attached instructions. Figure 5 According to the polar figure orientation, the grains with larger grain sizes, 1#, 2#, 3#, 4#, and 5#, are selected from the sample surface, including the grain normal direction. n i and rolling direction l i , respectively (1.1 1.11)1 / [-1 1 0]1, (1 1 2.3)2 / [1 -1 0]2, (0 0 1)3 / [1 1 0]3, (1 1.3 1)4 / [1 -1 0.3]4, (0 11)5 / [1 -1 2]5. The original test surface was reconstructed using white light interferometry, and the average height H of the original grains was measured in units of grains. 1原 =1.933, H 2原 =1.934, H 3原 =1.939, H 4原 =1.935, H 5原 =1.933.

[0119] Step S 13 Test the milling rate and establish a milling rate-crystallographic orientation mapping relationship. Prepare the milling solution: NaOH (200g / L), Al (5g / L), room temperature. Mill the aluminum alloy after degreasing and cleaning. Set the milling time to t = 15 minutes and measure the surface grain size after milling. 6 #Chemical milling height H 1终 =1.885mm, H 2终 =1.889mm, H 3终 =1.911mm, H 4终 =1.887mm, H 5终=1.893mm. The milling depth is recorded as h1=H 1原 -H 1终 =0.048mm, h2=H 2原 -H 2终 =0.045mm, h3=H 3原 -H 3终 =0.028mm, h4=H 4原 -H 4终 =0.048mm, h5=H 5原 -H 5终 =0.040mm. Milling rate v 1=h1 / t=0.00322mm / min, v 2=h2 / t=0.00297mm / min, v 3=h3 / t=0.00187mm / min, v 4=h4 / t=0.00320mm / min, v 5=h5 / t=0.00264mm / min. Since chemical reactions during milling generally prioritize destroying low-energy crystal planes, 5A02-O aluminum alloy is mainly composed of fcc parent phase, and the closest-packed crystal planes include (111), (11-1), (1-11), (-111), such as {111} of face-centered cubic fcc, {110} of body-centered cubic bcc, and {0001} of close-packed hexagonal hcp. Therefore, it is necessary to calculate the normal direction of the above crystal planes based on the normal direction of the closest-packed plane in each grain. The angle between the two. Generally, the closest packed plane is a crystal plane family, which contains multiple closest packed planes, defined here as ,in j =1,…,m. The minimum angles between the normal to the crystal plane in each grain and the closest-packed plane are 2.53°, 23.1°, 54.7°, 7.33°, and 35.3°, respectively. The closest-packed planes with the minimum angles between the normal to the crystal plane in grains 1#-5# are (111), (111), (111), or (1-11), or (-111), (111), (111), or (-111), and the milling rate of the closest-packed plane is calculated. =0.00323mm / min. The calculation method is as follows:

[0120]

[0121] Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain, Forn i The most densely packed surface with the smallest angle.

[0122] Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction d k Before chemical milling parts, the surface texture type and texture content of the raw material plate used for the parts are determined, as shown in the attached manual. Figure 6 As shown, the main textures are brass texture, pure copper texture, and S texture, which are {110} / <1-12>, {112} / <111> 、{123} / <634> According to the orientation distribution function ODF, as shown in the appendix of the manual Figure 7 As shown, the volume fraction of brass texture {110} / <1-12> is obtained d 1 =51.3%, pure copper texture {112} / <111> Volume fraction d 2 =26.3%, S texture {123} / <634> Volume fraction d 3 =22.4%.

[0123] Step S3. Calculate the crystal plane normal direction under different texture types using the same milling solution as step S1. n k ′ Minimum angle with the closest packed surface i k , the minimum angle under the three textures i 1 =35.3°, i 2 =19.5°, i 3 =22.2°. The calculation method is as follows:

[0124]

[0125] Where, It is the normal direction of the most closely packed plane in the crystal.

[0126] Step S4. Calculate milling rate =0.00282mm / min, the calculation method is as follows:

[0127]

[0128] Step S5. Then, the milling time parameter is calculated according to the milling depth. The thickness accuracy after milling can reach ±0.05mm.

[0129] The traditional milling rate test method is to calculate the milling rate of 5A02-O aluminum plate by weighing method. =0.00505mm / min, and then the milling time parameters are calculated according to the milling depth. The thickness accuracy after milling can only reach ±0.1mm. In contrast, this method can achieve higher-precision control of the milling dimensions of aluminum alloy thin plates, and can also achieve personalized and precise control for thin plates with different texture types.

[0130] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical solutions and technical concepts of the present invention without creative mental work, which all fall within the scope of protection of the present invention.

Claims

1. A method for precise dimensional control of thin plate chemical milling based on texture, characterized by: The following steps are involved: Step S1. Establish the relationship between the milling rate and the crystallographic orientation mapping, and calculate the milling rate of the most densely packed surface. : Where, n is the number of grains, v i for i #Grain milling rate, n i for i #Normal direction of the grain surface, For n i The most densely packed surface with the smallest angle; Step S2. Determine the texture type of the sheet material n k ′ / l k ′ and various texture types n k ′ / l k ′ Volume fraction δ k ； Step S3. Calculate the crystal plane normal under different texture types n k ′ Minimum angle with the closest packed surface θ k ; Step S4. Calculate milling rate : Step S5: Calculate the milling time according to the milling depth.

2. The method for precise dimensional control of thin plate chemical milling based on texture according to claim 1, characterized in that: In step S3, the minimum angle θ k The calculation method is: Where, It is the normal direction of the most closely packed plane in the crystal.

3. The method for precise dimensional control of thin plate chemical milling based on texture according to claim 1, characterized in that: Each texture type n k ′ / l k ′ Volume fraction δ k The calculation method is: obtained according to the orientation distribution function ODF.

4. A method for precise dimensional control of thin plate chemical milling based on texture according to any one of claims 1 to 3, characterized in that: The step S1 specifically includes the following steps: Step S 11 . Prepare chemical milling test blocks; Step S 12 Determination of crystal orientation and original height of test surfaces in chemically milled test blocks; Step S 13 . Test the milling rate; Step S 14 . Calculate the milling rate of the densest surface .

5. The method for precise control of the size of thin plate chemical milling based on texture according to claim 4, characterized in that: The step S 11 Specifically, it means: selecting raw material plates of the same material, and obtaining chemical milling test blocks through heat treatment; one side of the chemical milling test block is the test surface, and the other side is the non-test surface; the test surface is polished, and the non-test surface is protected with chemical milling glue.

6. The method for precise control of the size of thin plate chemical milling based on texture according to claim 4, characterized in that: The step S 12 Determining the crystal orientation of the test surface in the chemical milling test block specifically refers to: determining the texture type and texture orientation of the test surface in the chemical milling test block, and obtaining the grain size of the sample surface. i #Orientation, i =1,…,n.

7. The method for precise dimensional control of thin plate chemical milling based on texture according to claim 6, characterized in that: The orientation includes the normal direction of the crystal plane of the grain n i and rolling direction l i .

8. The method for precise dimensional control of thin plate chemical milling based on texture according to claim 4, characterized in that: The step S 12 Determining the original height of the test surface in the milling test block specifically refers to: reconstructing the original test surface and measuring the average height of the original grains in units of grains .

9. The method for precise dimensional control of thin plate chemical milling based on texture according to claim 4, characterized in that: The step S 14 Specifically refers to: according to the crystal plane normal and the closest packed plane normal in each grain The angle between the crystal plane and the normal is obtained. n i The most densely packed surface with the smallest angle , calculate the milling rate of the densest surface .

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