Production process of high-strength precise titanium foil material for low-cost 3C flexible screen

Abstract

The application relates to the technical field of foil production, in particular to a low-cost high-strength precise titanium foil production process for 3C flexible screens; the process comprises the following steps: S1, blanking: taking a plate or a coiled strip as raw material; S2, rolling: feeding the raw material into a rolling mill to roll to obtain a semi-finished product titanium foil; S3, annealing: feeding the semi-finished product titanium foil into a vacuum furnace to perform annealing treatment to obtain a titanium foil. When the deformation rate is relatively large, the first lubricant at high temperature is sprayed to improve the plastic deformation capacity of the raw material, then the two lubricants are combined, the stress concentration in the raw material is reduced, the processing defects on the surface of the raw material are reduced, and when the deformation rate is relatively small, the second lubricant at low temperature is sprayed, the size of the raw material is more stable, and the machining precision is improved.

Description

Technical Field

[0001] This invention relates to the field of foil production technology, specifically to a low-cost production process for high-strength, high-precision titanium foil for 3C flexible screens. Background Technology

[0002] Flexible screens are a new type of display technology that offers better flexibility compared to traditional rigid screens, allowing for various irregular shapes and making them lightweight and portable. The production process typically involves using flexible materials as the substrate, such as plastic, glass, or metal substrates. Metal substrates, due to their significantly superior high-temperature resistance compared to plastic and glass substrates, show promising application prospects in small-scale flexible screens.

[0003] Titanium foil is a common choice for flexible screen substrates due to its excellent high-temperature resistance and flexibility. Rolling is currently the main production process for titanium foil due to its lower production cost. However, the dimensional stability of titanium foil is poor during rolling, resulting in poor dimensional accuracy. Furthermore, stress concentration occurs within the titanium foil, leading to numerous surface defects and affecting its strength. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a low-cost production process for high-strength, high-precision titanium foil for flexible 3C screens.

[0005] The technical solution of this invention is: a low-cost production process for high-strength, high-precision titanium foil for flexible 3C screens, comprising the following steps:

[0006] S1, Material feeding

[0007] The sheet or roll is used as raw material (Note: In actual production, sheet or roll with a thickness greater than 0.4m is generally selected for cutting. The solution of this invention is also mainly for sheet or roll with a thickness greater than 0.4m), and the raw material is cleaned to obtain the cleaned raw material.

[0008] S2, Rolling

[0009] The cleaned raw material is fed into a rolling mill for multiple rolling passes until the raw material thickness reaches 0.05-0.1 mm, thus obtaining semi-finished titanium foil.

[0010] During the rolling process, when δ1≥1 / 2δ, the single-pass rolling deformation rate is 25-30%, and a first lubricant at 120-140℃ is sprayed onto the surface of the raw material before each rolling pass;

[0011] When 1 / 4δ≤δ1<1 / 2δ, the single-pass rolling deformation rate is 10~15%. Before each rolling pass, a first lubricant at 90~100℃ is sprayed onto the surface of the raw material, and after each rolling pass, a second lubricant at 10~20℃ is sprayed onto the surface of the raw material and left to stand for 2~3 minutes.

[0012] When δ1 < 1 / 4δ, the single-pass rolling deformation rate is 5-8%. After each rolling pass, a second lubricant at 5-10℃ is sprayed onto the surface of the raw material and left to stand for 1-2 minutes.

[0013] Where δ is the initial thickness of the raw material, and δ1 is the current thickness of the raw material;

[0014] S3, Annealing

[0015] The semi-finished titanium foil is sent into a vacuum furnace for annealing. After annealing, the semi-finished titanium foil is stretched and straightened to obtain titanium foil.

[0016] Explanation: In the above process, when the deformation rate is large, a high-temperature first lubricant is sprayed to improve the plastic deformation capacity of the raw material, reduce the processing difficulty, and improve processing efficiency. Then, by using the first lubricant in combination with the second lubricant, the raw material can be reduced without multiple annealing processes, thus reducing internal stress concentration. Moreover, the two lubricants can form a protective film on the surface of the raw material, reducing processing defects on the surface. When the deformation rate is small, a low-temperature second lubricant is sprayed to stabilize the grain structure, making the raw material size more stable and improving processing accuracy.

[0017] Furthermore, the rolling speed during the rolling process is 2-4 m / s, and the rolling force is 50-80 kN.

[0018] Note: The above rolling parameters can ensure production efficiency and reduce processing defects on the surface of raw materials.

[0019] Further, the cleaning step is as follows: the raw material is immersed in the pickling solution for 5-10 minutes, and then the raw material is washed with water and dried in sequence; the pickling solution includes, by weight percentage: 30-40% nitric acid, 0.3-0.6% hydrofluoric acid, and the remainder is water.

[0020] Note: The above cleaning steps can effectively remove oil and oxide layers from the surface of raw materials, reduce processing defects, and ensure the accuracy of subsequent processing.

[0021] Further, the components of the first lubricant, by weight, include: 15-25 parts stearic acid, 35-40 parts trimethylolpropane oleate, 10-15 parts triisooctanoic acid glyceride, and 4-8 parts dialkyldiphenylamine;

[0022] The second lubricant comprises, by weight, 20-25 parts cocamidopropyl betaine, 8-12 parts triethanolamine, 5-10 parts pentaerythritol phosphate, 6-9 parts sorbitan monooleate, and 30-40 parts water.

[0023] Explanation: The first lubricant can make the surface of the raw material smoother, making grain boundary slip easier, improving the plastic deformation capacity of the raw material, and facilitating the expansion of plastic deformation. The second lubricant can absorb the temperature generated by the deformation of the material, stabilize the grain structure, reduce the shrinkage of the raw material after rolling, and when the first lubricant and the second lubricant are used together, they can reduce the internal stress concentration of the raw material and form a protective film on the surface of the raw material, reducing the processing defects on the surface of the raw material.

[0024] Furthermore, when δ1≥1 / 2δ, the spraying rate of the first lubricant is 300~400ml / m 2 ;

[0025] When 1 / 4δ≤δ1<1 / 2δ, the spraying rate of the first lubricant is 200~250ml / m 2 The second lubricant is sprayed at a rate of 150–200 ml / m. 2 ;

[0026] When δ1 < 1 / 4δ, the spraying rate of the second lubricant is 100–150 ml / m. 2 .

[0027] Note: Limiting the spraying amount of the first and second lubricants can ensure the performance of the titanium foil while reducing the waste of the first and second lubricants.

[0028] Furthermore, the annealing process is performed under a vacuum degree ≤ 1.0 × 10⁻⁶. -4 Under Pa conditions, the semi-finished titanium foil is kept at 550-580℃ for 30-40 minutes, then cooled in the furnace to 320-340℃, and then removed from the furnace and air-cooled to room temperature.

[0029] Note: Annealing can reduce residual stress in titanium foil, refine grains, improve the toughness of titanium foil, and reduce deformation and cracks on the surface of titanium foil.

[0030] Furthermore, the cooling rate during the furnace cooling process is 6–9 °C / min.

[0031] Note: Limiting the cooling rate can prevent the titanium foil from deforming and cracking due to excessive cooling, thus ensuring the annealing effect.

[0032] Furthermore, the straightening tension of the tension straightener is 60-80 kN, and the tensile deformation rate is 0.05-0.1%.

[0033] Note: Straightening can eliminate wrinkles and curls on titanium foil, making the titanium foil thickness uniform.

[0034] The beneficial effects of this invention are:

[0035] (1) When the deformation rate is large, the process of the present invention sprays a high-temperature first lubricant to improve the plastic deformation capacity of the raw material. Then, by using two lubricants together, the internal stress concentration of the raw material can be reduced and the processing defects on the surface of the raw material can be reduced. When the deformation rate is small, a low-temperature second lubricant is sprayed to make the raw material size more stable and improve the processing accuracy.

[0036] (2) The first lubricant of the present invention can improve the plastic deformation ability of the raw material, and the second lubricant can stabilize the size of the raw material and reduce the shrinkage of the raw material after rolling. When the first lubricant and the second lubricant are used together, they can reduce the internal stress concentration of the raw material and form a protective film on the surface of the raw material, thereby reducing the processing defects on the surface of the raw material. Detailed Implementation

[0037] To further illustrate the methods and effects of this invention, the technical solution of this invention will be clearly and completely described below in conjunction with experiments.

[0038] Example 1: A low-cost production process for high-strength, high-precision titanium foil for flexible 3C screens, comprising the following steps:

[0039] S1, Material feeding

[0040] Using 1.0mm thick boards as raw materials, the raw materials are cleaned to obtain cleaned raw materials. The cleaning steps are as follows: the raw materials are immersed in pickling solution for 8 minutes, followed by washing with water and drying. The pickling solution contains, by weight percentage: 35% nitric acid, 0.5% hydrofluoric acid, and the remainder is water.

[0041] S2, Rolling

[0042] As shown in Table 1 below, the cleaned raw material is fed into the rolling mill for 19 rolling passes until the raw material thickness reaches 0.1 mm, thus obtaining semi-finished titanium foil.

[0043] During the rolling process, when δ1≥1 / 2δ, the single-pass rolling deformation rate is 25-30%. Before each rolling pass, a first lubricant at 130℃ is sprayed onto the surface of the raw material, and the spraying amount of the first lubricant is 350ml / m. 2 ;

[0044] When 1 / 4δ≤δ1<1 / 2δ, the single-pass rolling deformation rate is 10~15%. Before each rolling pass, a first lubricant at 95℃ is sprayed onto the raw material surface, and after each rolling pass, a second lubricant at 15℃ is sprayed onto the raw material surface and allowed to stand for 2.5 minutes. The spraying amount of the first lubricant is 220ml / m. 2 The second lubricant was sprayed at a rate of 170 ml / m. 2 ;

[0045] When δ1 < 1 / 4δ, the single-pass rolling deformation rate is 5-8%. After each rolling pass, a second lubricant at 8°C is sprayed onto the raw material surface and allowed to stand for 1.5 minutes. The spraying amount of the second lubricant is 120 ml / m. 2 ;

[0046] Where δ is the initial thickness of the raw material, and δ1 is the current thickness of the raw material; the rolling speed is 3m / s and the rolling force is 65kN;

[0047] Table 1. Rolling deformation rate data for each pass in this embodiment.

[0048]

[0049] S3, Annealing

[0050] The semi-finished titanium foil was placed in a vacuum furnace for annealing. After annealing, the semi-finished titanium foil was stretched and straightened to obtain titanium foil. The annealing method was as follows: under a vacuum degree of 1.0 × 10⁻⁶... -4 Under Pa conditions, the semi-finished titanium foil was kept at 560℃ for 35 min, and then cooled to 330℃ in the furnace at a cooling rate of 7℃ / min. After that, it was removed from the furnace and air-cooled to room temperature. The straightening tension was 70kN and the tensile deformation rate was 0.08%.

[0051] The components of the first lubricant, by weight, include: 20 parts stearic acid, 38 parts trimethylolpropane oleate, 12 parts triisooctanoic acid glyceride, and 6 parts dialkyldiphenylamine.

[0052] The second lubricant comprises, by weight, 23 parts cocamidopropyl betaine, 10 parts triethanolamine, 8 parts pentaerythritol phosphate, 7 parts sorbitan monooleate, and 35 parts water.

[0053] Example 2: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the temperature of the first lubricant is 120℃; when 1 / 4δ≤δ1<1 / 2δ, the temperature of the first lubricant is 90℃ and the temperature of the second lubricant is 10℃; when δ1<1 / 4δ, the temperature of the second lubricant is 5℃.

[0054] Example 3: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the temperature of the first lubricant is 140℃; when 1 / 4δ≤δ1<1 / 2δ, the temperature of the first lubricant is 100℃ and the temperature of the second lubricant is 20℃; when δ1<1 / 4δ, the temperature of the second lubricant is 10℃.

[0055] Example 4: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the spraying amount of the first lubricant is 300ml / m 2When 1 / 4δ≤δ1<1 / 2δ, the spraying rate of the first lubricant is 200ml / m. 2 The second lubricant was sprayed at a rate of 150 ml / m. 2 When δ1 < 1 / 4δ, the spraying rate of the second lubricant is 100 ml / m. 2 .

[0056] Example 5: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the spraying amount of the first lubricant is 400ml / m 2 When 1 / 4δ≤δ1<1 / 2δ, the spraying rate of the first lubricant is 250ml / m. 2 The second lubricant was sprayed at a rate of 200 ml / m. 2 When δ1 < 1 / 4δ, the spraying rate of the second lubricant is 150 ml / m. 2 .

[0057] Example 6: This example is basically the same as Example 1, except that the components of the first lubricant include, by weight, 15 parts stearic acid, 35 parts trimethylolpropane oleate, 10 parts triisooctanoic acid glyceride, and 4 parts dialkyldiphenylamine.

[0058] Example 7: This example is basically the same as Example 1, except that the components of the first lubricant include, by weight, 25 parts stearic acid, 40 parts trimethylolpropane oleate, 15 parts triisooctanoic acid glyceride, and 8 parts dialkyldiphenylamine.

[0059] Example 8: This example is basically the same as Example 1, except that the components of the second lubricant, by weight, include: 20 parts cocamidopropyl betaine, 8 parts triethanolamine, 5 parts pentaerythritol phosphate, 6 parts sorbitan monooleate, and 30 parts water.

[0060] Example 9: This example is basically the same as Example 1, except that the components of the second lubricant, by weight, include: 25 parts cocamidopropyl betaine, 12 parts triethanolamine, 10 parts pentaerythritol phosphate, 9 parts sorbitan monooleate, and 40 parts water.

[0061] Example 10: This example is basically the same as Example 1, except that the semi-finished titanium foil is kept at 550°C for 35 minutes.

[0062] Example 11: This example is basically the same as Example 1, except that the semi-finished titanium foil is kept at 580°C for 35 minutes.

[0063] Example 12: This example is basically the same as Example 1, except that the semi-finished titanium foil is cooled to 320°C in the furnace, and the cooling rate during the furnace cooling process is 6°C / min.

[0064] Example 13: This example is basically the same as Example 1, except that the semi-finished titanium foil is cooled to 340°C in the furnace, and the cooling rate during the furnace cooling process is 9°C / min.

[0065] Example 14: This example is basically the same as Example 1, except that the thickness of the raw material is 0.8 mm.

[0066] Example 15: This example is basically the same as Example 1, except that the thickness of the raw material is 1.2 mm.

[0067] Comparative Example 1: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the single-pass rolling deformation rate is 20-25%; when 1 / 4δ≤δ1<1 / 2δ, the single-pass rolling deformation rate is 5-10%; and when δ1<1 / 4δ, the single-pass rolling deformation rate is 2-5%.

[0068] Comparative Example 2: This example is basically the same as Example 1, except that when δ1≥1 / 2δ, the single-pass rolling deformation rate is 30-35%; when 1 / 4δ≤δ1<1 / 2δ, the single-pass rolling deformation rate is 15-20%; and when δ1<1 / 4δ, the single-pass rolling deformation rate is 8-12%.

[0069] Comparative Example 3: This example is basically the same as Example 1, except that the single-pass rolling deformation rate is 10-15% throughout the entire process.

[0070] Comparative Example 4: This example is basically the same as Example 1, except that the temperature of the first lubricant is always 95°C and the temperature of the second lubricant is always 15°C.

[0071] Comparative Example 5: This example is basically the same as Example 1, except that the spraying amount of the first lubricant is always 220 ml / m. 2 The spray volume of the second lubricant was consistently 170 ml / m. 2 .

[0072] Comparative Example 6: This example is basically the same as Example 1, except that the first lubricant is used instead of the second lubricant.

[0073] Comparative Example 7: This example is basically the same as Example 1, except that a second lubricant is used instead of the first lubricant.

[0074] Comparative Example 8: This example is basically the same as Example 1, except that commercially available rolling lubricating oil is used instead of the first lubricant and the second lubricant.

[0075] Comparative Example 9: This example is basically the same as Example 1, except that the semi-finished titanium foil is kept at 560°C for 35 minutes and then directly removed from the furnace and air-cooled.

[0076] Experimental Example: To investigate the influence of process parameters on the properties of titanium foil in each embodiment, performance tests were conducted on the titanium foil prepared in each embodiment. The specific investigation is as follows:

[0077] 1. Investigating the effect of rolling deformation rate range on the properties of titanium foil.

[0078] Using Example 1 and Comparative Examples 1-4 as experimental comparisons, the properties of titanium foil under different rolling deformation rate ranges are shown in Table 2 below:

[0079] Table 2 Properties of titanium foil under different rolling deformation rates

[0080] Example 1 512 ±0.004 Comparative Example 2 514 ±0.004 Comparative Example 3 483 ±0.008 Comparative Example 4 445 ±0.030

[0081] As shown in Table 2, compared with Comparative Examples 2 and 3, the tensile strength of titanium foil in Example 1 gradually increases and the thickness tolerance gradually decreases as the range of single-pass rolling deformation rate decreases. Among them, Example 1 has the highest tensile strength and the smallest thickness tolerance, which indicates that the titanium foil in Example 1 has the highest strength and the best dimensional accuracy. As the range of single-pass rolling deformation rate continues to decrease, the performance of titanium foil begins to show no significant change. However, the decrease in the range of single-pass rolling deformation rate will lead to an increase in the number of rolling passes. Therefore, from a cost perspective, the rolling deformation rate range selected in Example 1 is the optimal one.

[0082] Compared with Comparative Example 4, in Example 1, the tensile strength of the titanium foil decreased and the dimensional tolerance increased after the single-pass rolling deformation rate range remained unchanged. This may be because the processing method of changing the rolling deformation rate range can reduce internal defects of the titanium foil and reduce shrinkage after rolling.

[0083] 2. Investigate the effects of temperature and spraying amount of the first and second lubricants on the properties of titanium foil.

[0084] Using Examples 1-5 and Comparative Examples 4 and 5 as experimental comparisons, the titanium foil properties of the first lubricant and the second lubricant under different temperatures and spray amounts are shown in Table 3 below:

[0085] Table 3. Titanium foil properties under different temperatures and spray amounts with the first and second lubricants.

[0086] Example 1 512 ±0.004 Example 2 503 ±0.006 Example 3 495 ±0.006 Example 4 505 ±0.005 Example 5 490 ±0.006 Comparative Example 4 472 ±0.009 Comparative Example 5 476 ±0.008

[0087] As can be seen from the data in Table 3, the temperature and spraying amount of the first and second lubricants both affect the performance of the titanium foil. If the temperature of the first and second lubricants is too high or too low, or the spraying amount is too high or too low, the strength of the titanium foil will decrease and the dimensional accuracy will deteriorate. The titanium foil of Example 1 has the highest strength and the best dimensional accuracy. Therefore, the temperature and spraying amount of the first and second lubricants selected in Example 1 are optimal.

[0088] Compared with Comparative Examples 4 and 5, keeping the temperature and spray volume of the first and second lubricants constant in Example 1 resulted in a decrease in the strength and a deterioration in the dimensional accuracy of the titanium foil. This may be because keeping the temperature and spray volume of the first and second lubricants constant would cause the plastic deformation capacity of the titanium foil to not match the amount of deformation, resulting in defects during the titanium foil processing.

[0089] 3. Investigate the effect of the ratio of the first lubricant to the second lubricant on the properties of titanium foil.

[0090] Using Examples 1, 6-9, and Comparative Examples 6-8 as experimental comparisons, the titanium foil properties under different component ratios of the first and second lubricants are shown in Table 4 below:

[0091] Table 4. Titanium foil properties under different composition ratios of the first and second lubricants.

[0092] Example 1 512 ±0.004 Example 6 503 ±0.006 Example 7 496 ±0.006 Example 8 504 ±0.005 Example 9 498 ±0.007 Comparative Example 6 479 ±0.009 Comparative Example 7 473 ±0.011 Comparative Example 8 432 ±0.018

[0093] As shown in Table 4, the composition ratio of the first lubricant and the second lubricant both affect the performance of the titanium foil. The titanium foil of Example 1 has the highest strength and the best dimensional accuracy. Therefore, the composition ratio of the first lubricant and the second lubricant selected in Example 1 is the optimal.

[0094] Compared with Comparative Examples 6 and 7, in Example 1, using only the first lubricant or the second lubricant resulted in a decrease in the strength and a deterioration in the dimensional accuracy of the titanium foil. This may be because using only one lubricant cannot improve the plastic deformation capacity of the titanium foil and cannot stabilize the size of the titanium foil. Compared with Comparative Example 8, in Example 1, after replacing the first lubricant and the second lubricant with commercially available rolling lubricating oil, the strength of the titanium foil decreased significantly and the dimensional accuracy deteriorated significantly. This may be because commercially available rolling lubricating oil cannot improve the plastic deformation capacity of the titanium foil. Therefore, the first lubricant and the second lubricant in Example 1 are optimal.

[0095] 4. Investigating the effect of annealing parameters on the properties of titanium foil

[0096] Using Examples 1, 10-13, and Comparative Example 9 as experimental comparisons, the properties of titanium foil under different annealing parameters are shown in Table 5 below:

[0097] Table 5 Properties of titanium foil under different annealing parameters

[0098] Example 1 512 ±0.004 Example 10 497 ±0.007 Example 11 492 ±0.006 Example 12 501 ±0.005 Example 13 499 ±0.006 Comparative Example 9 468 ±0.009

[0099] As shown in Table 5, the annealing parameters affect the performance of titanium foil. Too high or too low holding temperature, or too fast or too slow cooling rate, will lead to a decrease in the strength of titanium foil and a deterioration in dimensional accuracy. Therefore, the annealing parameters selected in Example 1 are optimal.

[0100] Compared with Comparative Example 9, the titanium foil strength decreased and the dimensional accuracy deteriorated after direct air cooling after being taken out of the furnace in Example 1. This may be because the cooling rate was too fast, resulting in more cracks inside the titanium foil. Therefore, the annealing method selected in Example 1 is the optimal one.

[0101] 5. Investigate the effect of raw material thickness on the properties of titanium foil.

[0102] Using Examples 1 and 14-15 as experimental comparisons, the properties of titanium foil with different raw material thicknesses are shown in Table 6 below:

[0103] Table 6 Properties of titanium foil with different raw material thicknesses

[0104] Example 1 512 ±0.004 Example 14 506 ±0.005 Example 15 515 ±0.004

[0105] As shown in Table 6, choosing a thicker raw material leads to a decrease in the strength and dimensional accuracy of the titanium foil. Choosing a thinner raw material results in a small difference in the performance of the titanium foil, but using a thinner raw material is more expensive. Therefore, the raw material thickness chosen in Example 1 is optimal.

Claims

1. A low-cost manufacturing process for high-strength, high-precision titanium foil for flexible 3C screens, characterized in that, Includes the following steps: S1, Material feeding Using sheet metal or rolls as raw materials, and cleaning the raw materials to obtain cleaned raw materials; The cleaning steps are as follows: immerse the raw material in the pickling solution for 5-10 minutes, and then wash and dry the raw material in sequence; the pickling solution includes, by weight percentage: 30-40% nitric acid, 0.3-0.6% hydrofluoric acid, and the remainder is water; S2, Rolling The cleaned raw material is fed into a rolling mill for multiple rolling passes until the raw material thickness reaches 0.05~0.1mm, resulting in semi-finished titanium foil. During the rolling process, when δ1≥1 / 2δ, the single-pass rolling deformation rate is 25~30%. Before each rolling pass, a first lubricant at 120~140℃ is sprayed onto the surface of the raw material; the spraying amount of the first lubricant is 300~400ml / m. 2 ; When 1 / 4δ≤δ1<1 / 2δ, the single-pass rolling deformation rate is 10~15%. Before each rolling pass, a first lubricant at 90~100℃ is sprayed onto the raw material surface, and after each rolling pass, a second lubricant at 10~20℃ is sprayed onto the raw material surface and allowed to stand for 2~3 minutes. The spraying amount of the first lubricant is 200~250ml / m. 2 The second lubricant is sprayed at a rate of 150~200ml / m. 2 ; When δ1 < 1 / 4δ, the single-pass rolling deformation rate is 5-8%. After each rolling pass, a second lubricant at 5-10℃ is sprayed onto the raw material surface and allowed to stand for 1-2 minutes. The spraying amount of the second lubricant is 100-150 ml / m. 2 ; Where δ is the initial thickness of the raw material, and δ1 is the current thickness of the raw material; the rolling speed during rolling is 2~4m / s, and the rolling force is 50~80kN; The components of the first lubricant, by weight, include: 15-25 parts stearic acid, 35-40 parts trimethylolpropane oleate, 10-15 parts triisooctanoic acid glyceride, and 4-8 parts dialkyldiphenylamine; The second lubricant comprises, by weight, 20-25 parts of cocamidopropyl betaine, 8-12 parts of triethanolamine, 5-10 parts of pentaerythritol phosphate, 6-9 parts of sorbitan monooleate, and 30-40 parts of water. S3, Annealing The semi-finished titanium foil is placed in a vacuum furnace for annealing. After annealing, the semi-finished titanium foil is stretched and straightened to obtain titanium foil. The annealing method is as follows: under a vacuum degree ≤1.0×10⁻⁶... -4 Under Pa conditions, the semi-finished titanium foil is kept at 550~580℃ for 30~40min, then cooled in the furnace to 320~340℃, and then air-cooled to room temperature; the cooling rate during the furnace cooling process is 6~9℃ / min; the straightening tension is 60~80kN, and the tensile deformation rate is 0.05~0.1%.

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