A rolling method for low-expansion alloy ultra-thin precision foils

Abstract

The application discloses a kind of low expansion alloy ultra-thin precision foil rolling method, comprising: (1) roll system configuration, one intermediate roll taper is 0.28x180mm, two intermediate free roller convexity is 0.15mm, two intermediate driving roll is flat roll;(2) rolling process design, material preparation is less than 1.5%, the rolling speed is 140-150m / min, the rolling oil flow is 600-800L / min, the first, second, third pass uses the M2 work roll with a diameter of 28-30mm, subsequent pass uses the M2 work roll with a diameter of 25-28mm, the roughness Ra of work roll used in last two passes is 0.15-0.17 μm, the same roll diameter difference of work roll is less than 3 μm.The application optimizes rolling process and roll system configuration, effectively controls the flatness of product, and the thickness tolerance fluctuation is small, the surface quality is stable, solves the technical problems of low expansion alloy ultra-thin precision stainless steel foil product flatness, surface quality is unstable, and is suitable for industrialized mass production, meets the high-end industry high-quality requirements of ultra-thin precision stainless steel foil.

Description

Technical Field

[0001] This invention belongs to the field of stainless steel foil rolling technology, and particularly relates to a method for rolling ultra-thin precision foil of low expansion alloy. Background Technology

[0002] Low-expansion alloy ultrathin precision stainless steel foil refers to cold-rolled stainless steel strip with a thickness of less than 0.05 mm that achieves a very small or even near-zero coefficient of thermal expansion within a temperature range near room temperature. The main steel grades include nickel-based alloys such as 4J32, 4J36, and 4J42. In the 1920s, low-expansion alloys replaced platinum as lead wires for glass sealing, significantly reducing costs. In the 1950s and 60s, the applications of low-expansion alloys continued to expand, mainly used in radio tubes, bimetallic strips for temperature control in thermostats, length scales, and geodetic baseline rulers. In the 1980s and 90s, they were widely used in microwave technology, liquid gas storage containers, shadow mask steel strips for color televisions, overhead power transmission line cores, resonant cavities, laser collimator cavities, and substrates for three-step repeatable lithography cameras. Since the beginning of the 21st century, with the rapid development of aerospace technology, new applications have included structural components in aerospace remote sensors, precision lasers, optical measurement systems and waveguides, support systems for giant lenses in microscopes and astronomical telescopes, and various scientific instruments that require the installation of lenses.

[0003] Currently, the thinnest thickness of this low-expansion alloy product in the market has reached 0.025mm. Due to its excellent mechanical properties and lightweight characteristics, it has been favored by high-end and cutting-edge markets. As applications increasingly demand higher performance and precision, the requirements for steel strip thickness, shape, and surface finish are becoming more stringent. However, its higher nickel content, compared to austenitic stainless steel, makes it more prone to roller adhesion, relatively higher heat generation, and excessive material plasticity, resulting in surface roller marks and poor flatness.

[0004] Therefore, it is necessary to develop a rolling method for low-expansion alloy ultra-thin precision foils. By optimizing the rolling process and roll configuration, the rolling surface and plate shape can be improved, and the production of high-end products of low-expansion alloy ultra-thin precision stainless steel foils can be stabilized to meet customer needs. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the present invention provides a method for rolling low-expansion alloy ultrathin precision foil, comprising: (1) Roller system configuration The rolling process is carried out using a 20-roll mill. The taper of the intermediate roll of the first mill is designed to be 0.28*180mm, the crown of the intermediate free roll of the second mill is designed to be 0.15mm, and the intermediate drive roll of the second mill is designed to be a flat roll. (2) Rolling process design The low-expansion alloy raw material of initial thickness is rolled into low-expansion alloy ultra-thin precision stainless steel foil of target thickness using a 20-roll mill in multiple passes. The difference between the raw material and the sheet is controlled to be less than 1.5%, the rolling speed is controlled to be 140-150 m / min, and the rolling oil flow rate is controlled to be 600-800 L / min. The diameter used in the 1st, 2nd, and 3rd passes is [missing information]. 28-30mm M2 work rolls, subsequent passes use a diameter of [missing information]. The work rolls used in the last two passes are M2 work rolls with a surface roughness Ra of 0.15-0.17μm, and the diameter difference between the work rolls is controlled to be less than 3μm.

[0006] Furthermore, in the above-mentioned method for rolling ultra-thin precision foil of low-expansion alloy, after the first rolling pass is completed, the tail steel sleeve is replaced with a steel sleeve with a taper of less than 0.2mm.

[0007] Furthermore, in the above-mentioned method for rolling ultra-thin precision foil of low-expansion alloy, the work rolls are replaced after each rolling pass.

[0008] Furthermore, in the above-mentioned method for rolling ultra-thin precision foil of low-expansion alloy, the surface roughness Ra of the work rolls used in the other passes, except for the last two passes, is 0.35-0.45μm.

[0009] Furthermore, in the above-mentioned low-expansion alloy ultrathin precision foil rolling method, the rolling deformation gradually decreases from the first pass to the last pass.

[0010] Furthermore, in the above-mentioned low-expansion alloy ultrathin precision foil rolling method, the rolling force gradually decreases from the first pass to the last pass.

[0011] Furthermore, in the above-mentioned method for rolling ultra-thin precision foil of low-expansion alloy, the 20-roll mill is a SUNDWIG four-column 20-roll mill.

[0012] Furthermore, in the above-mentioned method for rolling low-expansion alloy ultra-thin precision foil, the width of the low-expansion alloy ultra-thin precision stainless steel foil is 500-600mm.

[0013] The low-expansion alloy ultrathin precision foil rolling method of the present invention has the following advantages and beneficial effects: By optimizing the rolling process and roll configuration, ultra-thin low-expansion alloy precision stainless steel foil products are produced, which effectively controls the flatness of the products, minimizes thickness tolerance fluctuations, and ensures stable surface quality. This solves the technical problems of poor flatness and unstable surface quality of existing low-expansion alloy ultra-thin precision stainless steel foil products, and is suitable for large-scale industrial production, meeting the high-end industry and high-quality requirements of ultra-thin precision stainless steel foil. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0015] The low-expansion alloy ultrathin precision foil rolling method of the present invention is used for rolling cold-rolled stainless steel strip with a thickness of less than 0.05 mm, which obtains a very small or even close to zero coefficient of thermal expansion in a temperature range near room temperature. The low-expansion alloy ultrathin precision foil rolling method includes: (1) Roller system configuration The rolling process is carried out using a 20-roll mill. The taper of the intermediate roll of the first mill is designed to be 0.28*180mm, the crown of the intermediate free roll of the second mill is designed to be 0.15mm, and the intermediate drive roll of the second mill is designed to be a flat roll (i.e., crown is 0mm). (2) Rolling process design The low-expansion alloy raw material of initial thickness is rolled into low-expansion alloy ultra-thin precision stainless steel foil of target thickness using a 20-roll mill in multiple passes. The difference between the raw material and the sheet is controlled to be less than 1.5%, the rolling speed is controlled to be 140-150 m / min, and the rolling oil flow rate is controlled to be 600-800 L / min. The diameter used in the 1st, 2nd, and 3rd passes is [missing information]. 28-30mm M2 (molybdenum-based high-speed steel) work rolls, with a diameter of [missing value] used in subsequent passes. The work rolls used in the last two passes are M2 work rolls with a surface roughness Ra of 0.15-0.17μm, and the diameter difference between the work rolls is controlled to be less than 3μm.

[0016] Furthermore, in the low-expansion alloy ultra-thin precision foil rolling method of the present invention, since the taper of the steel sleeve affects the actual plate shape, after the first rolling pass is completed, the tail steel sleeve is replaced with a steel sleeve with a taper of less than 0.2 mm.

[0017] Furthermore, in the low-expansion alloy ultra-thin precision foil rolling method of the present invention, the work roll is replaced after each rolling pass. The reason is that the low-expansion alloy has a high nickel content, which is prone to sticking to the roll, resulting in sticking mark defects. Replacing the work roll after each rolling pass can effectively avoid the above phenomenon.

[0018] Furthermore, in the low-expansion alloy ultrathin precision foil rolling method of the present invention, the surface roughness Ra of the work rolls used in the other passes, except for the last two passes, is 0.35-0.45 μm.

[0019] Furthermore, in the low-expansion alloy ultrathin precision foil rolling method of the present invention, the rolling deformation gradually decreases from the first pass to the last pass.

[0020] Furthermore, in the low-expansion alloy ultrathin precision foil rolling method of the present invention, the rolling force gradually decreases from the first pass to the last pass.

[0021] In one specific embodiment, in the low-expansion alloy ultra-thin precision foil rolling method of the present invention, the twenty-roll mill is a SUNDWIG four-column twenty-roll mill.

[0022] In one specific embodiment, in the low-expansion alloy ultra-thin precision foil rolling method of the present invention, the width of the low-expansion alloy ultra-thin precision stainless steel foil is 500-600mm.

[0023] In the low expansion alloy ultrathin precision foil rolling method of the present invention, since the low expansion alloy has strong plasticity, the rolling speed has a great influence on the plate shape. The rolling speed must be stably controlled and should not be too fast. Therefore, the rolling speed is controlled in the range of 140-150m / min.

[0024] In the low expansion alloy ultra-thin precision foil rolling method of the present invention, since the low expansion alloy has strong plasticity and relatively low rolling pressure, the intermediate free roll of the rolling mill must use a free roll with a 0.15mm crown.

[0025] The following detailed description of the low-expansion alloy ultrathin precision foil rolling method of the present invention, with reference to specific embodiments, illustrates this invention in detail.

[0026] Example 1 The low-expansion alloy ultrathin precision foil rolling method of Embodiment 1 of the present invention uses 4J36 steel grade low-expansion alloy with a thickness of 0.1 mm and a width of 580 mm as raw material to prepare 4J36 steel grade low-expansion alloy ultrathin precision stainless steel foil with a width of 580 mm, a thickness of 0.025 mm, and a surface roughness Ra of 0.15-0.25 μm. The difference between raw materials and the same plate is controlled to be less than 1.5%, including: (1) Roller system configuration The SUNDWIG four-column twenty-roll 650 mill was selected. The taper of the intermediate roll of the first mill is 0.28*180mm, the crown of the intermediate free roll of the second mill is 0.15mm (15 marks), and the intermediate drive roll of the second mill is designed as a flat roll. (2) Rolling process design The rolling process shall be performed according to the rolling process table shown in Table 1: Table 1 Rolling process table for Example 1

[0027] During the rolling process: First, adjust the preset plate shape curve convexity to 20, the preset convexity to 50%, and the preset intermediate roller to -20mm; For the first rolling pass, M2 material rolls with a roughness Ra of 0.35-0.45μm and a diameter difference of less than 3μm are selected. At the start, the plate shape is first adjusted and stabilized, and then the rolling speed is increased to 140-150m / min. After the first rolling pass is completed, the tail steel sleeve is replaced with a steel sleeve with a taper of less than 0.2mm. For the second to fifth rolling passes, M2 material rolls with a roughness Ra of 0.35-0.45μm and a diameter difference of less than 3μm are used. At the start, the plate shape is first adjusted and stabilized, and then the rolling speed is increased to 140-150m / min. For the 6th and 7th rolling passes, M2 material rolls with a roughness Ra of 0.15-0.17μm and a diameter difference of less than 3μm are used. At the start, the plate shape is first adjusted to be stable, and then the rolling speed is increased to 140-150m / min. The rolls need to be replaced after each rolling pass.

[0028] Actual testing showed that the main technical indicators of the low-expansion alloy ultrathin precision stainless steel foil obtained by the low-expansion alloy ultrathin precision foil rolling method of Example 1 of this invention can achieve the following: Thickness deviation: 0.025±0.001mm; Straightness: within 6IU; Surface roughness Ra: 0.15-0.25 μm; Surface quality: The surface is uniform and consistent, free from defects such as color difference, spiral marks, and sand marks, and the gloss is uniform in all directions.

[0029] Example 2 The low-expansion alloy ultrathin precision foil rolling method of Embodiment 2 of the present invention uses 4J32 steel grade low-expansion alloy with a thickness of 0.1 mm and a width of 550 mm as raw material to prepare 4J32 steel grade low-expansion alloy ultrathin precision stainless steel foil with a width of 550 mm, a thickness of 0.025 mm, and a surface roughness Ra of 0.15-0.25 μm. The difference between raw materials and the same plate is controlled to be less than 1.5%, including: (1) Roller system configuration The SUNDWIG four-column twenty-roll 650 mill was selected. The taper of the intermediate roll of the first mill is 0.28*180mm, the crown of the intermediate free roll of the second mill is 0.15mm (15 marks), and the intermediate drive roll of the second mill is designed as a flat roll. (2) Rolling process design The rolling process shall be performed according to the rolling process table shown in Table 2: Table 2 Rolling process table for Example 2

[0030] During the rolling process: First, adjust the preset plate shape curve convexity to 25, the preset convexity to 80%, and the preset intermediate roller to 25mm; For the first rolling pass, M2 material rolls with a roughness Ra of 0.35-0.45μm and a diameter difference of less than 3μm are selected. At the start, the plate shape is first adjusted and stabilized, and then the rolling speed is increased to 140-150m / min. After the first rolling pass is completed, the tail steel sleeve is replaced with a steel sleeve with a taper of less than 0.2mm. For the second to fifth rolling passes, M2 material rolls with a roughness Ra of 0.35-0.45μm and a diameter difference of less than 3μm are used. At the start, the plate shape is first adjusted and stabilized, and then the rolling speed is increased to 140-150m / min. For the 6th and 7th rolling passes, M2 material rolls with a roughness Ra of 0.15-0.17μm and a diameter difference of less than 3μm are used. At the start, the plate shape is first adjusted to be stable, and then the rolling speed is increased to 140-150m / min. The rolls need to be replaced after each rolling pass.

[0031] Actual testing showed that the main technical indicators of the low-expansion alloy ultrathin precision stainless steel foil obtained by the low-expansion alloy ultrathin precision foil rolling method of Example 2 of this invention can achieve the following: Thickness deviation: 0.025±0.001mm; Straightness: within 6IU; Surface roughness Ra: 0.15-0.25 μm; Surface quality: The surface is uniform and consistent, free from defects such as color difference, spiral marks, and sand marks, and the gloss is uniform in all directions.

[0032] In summary, compared with the prior art, the low-expansion alloy ultrathin precision foil rolling method of the present invention has the following advantages and beneficial effects: This invention optimizes the rolling process and roll configuration to produce ultra-thin, low-expansion alloy precision stainless steel foil products. This effectively controls the flatness of the product, minimizes thickness tolerance fluctuations, and ensures stable surface quality. It solves the technical problems of poor flatness and unstable surface quality in existing low-expansion alloy ultra-thin precision stainless steel foil products. Furthermore, it is suitable for large-scale industrial production and meets the high-quality requirements of high-end industries for ultra-thin precision stainless steel foil.

[0033] It should be noted that, in this document, the term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for rolling ultrathin precision foil of low-expansion alloy, characterized in that, include: (1) Roller system configuration The rolling process is carried out using a 20-roll mill. The taper of the intermediate roll of the first mill is designed to be 0.28×180mm, the crown of the intermediate free roll of the second mill is designed to be 0.15mm, and the intermediate drive roll of the second mill is designed to be a flat roll. (2) Rolling process design The original thickness of low-expansion alloy 4J36 or 4J32 steel is rolled into the target thickness of ultra-thin precision low-expansion alloy foil using a 20-roll mill in multiple passes. The difference between the original thickness and the sheet thickness is controlled to be less than 1.5%. The rolling speed must be stably controlled at 140-150 m / min, and the rolling oil flow rate is controlled at 600-800 L / min. The diameter used in the first, second, and third passes is... 28-30mm M2 work rolls, subsequent passes use a diameter of [missing information]. The roughness Ra of the M2 work rolls with a diameter of 25-28mm is 0.35-0.45μm for all passes except the last two, and 0.15-0.17μm for the last two passes. The diameter difference between the work rolls is controlled to be less than 3μm. The rolling deformation and rolling force gradually decrease from the first pass to the last pass. The work rolls are replaced after each pass. After the first pass is completed, the tail steel sleeve is replaced with a steel sleeve with a taper of less than 0.2mm.

2. The method for rolling low-expansion alloy ultrathin precision foil according to claim 1, characterized in that, The 20-roll mill is a SUNDWIG four-column 20-roll mill.

3. The method for rolling low-expansion alloy ultrathin precision foil according to claim 1, characterized in that, The width of the low-expansion alloy ultrathin precision foil is 500-600mm.

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