A grinding-free fabrication process and application of a double-layer metal composite ultrathin strip

Abstract

This invention provides a grinding-free preparation process and application for ultra-thin bilayer metal composite strips, relating to the technical field of ultra-thin bilayer metal composite strips. The grinding-free preparation process includes steps such as metal substrate cutting, pre-rolling annealing, cleaning, combined rolling with roughened rolls and traditional flat rolls, post-rolling annealing, and cooling. This invention uses any two metals, such as copper foil, titanium foil, or stainless steel, as the substrate. By optimizing the annealing temperature and reduction rate, it achieves efficient composite under low reduction rate conditions, simplifying the process and improving production efficiency. The composite ultra-thin strip prepared by this invention exhibits a regular pit array structure on its surface, significantly improving interfacial bonding strength. It also possesses hydrophobicity, low thermal conductivity, drag reduction, and electromagnetic wave anti-reflection properties, making it suitable for high-end applications in the aerospace and electronics industries, with broad prospects.

Description

Technical Field

[0001] This invention relates to the field of double-layer metal composite ultrathin strip technology, and in particular to a grinding-free preparation process and application of double-layer metal composite ultrathin strip. Background Technology

[0002] Bilayer metal composite ultrathin strips are a novel type of composite material formed by composite technology using at least two alloys or metals with different physical properties, chemical properties, and mechanical properties. Through careful design and combination, these composite materials can fully utilize and leverage the performance advantages of each component material, effectively compensating for the limitations of a single material, thereby endowing the final product with superior overall performance. For this reason, bilayer metal composite ultrathin strips have demonstrated broad application potential and value in many high-tech and industrial fields such as aerospace, electronics and communications, and petrochemicals.

[0003] Currently, the composite technology for bilayer metal composite ultrathin strips mainly encompasses several methods, including solid-solid phase composite, solid-liquid phase composite, and liquid-liquid phase composite. Among these, rolling technology in the solid-solid phase composite field, with its significant advantages of low energy consumption and high efficiency, has become the mainstream production method for bilayer metal composite ultrathin strips widely adopted in the industry. Specifically, the rolling composite process for bilayer metal composite ultrathin strips can be subdivided into two categories: the first involves pre-rolling the raw material into a thinner layer before rolling composite; the second involves directly rolling composite the raw material and then further thinning the composite material. Both of these processes require meticulous grinding pretreatment of the interface to be composited before rolling composite, aiming to expose the fresh metal surface and ensure the smooth progress of the rolling composite process. Therefore, the final effect of rolling composite is closely related to the grinding process of the material surface and its post-treatment surface state, which leads to a complex and cumbersome entire preparation process for bilayer metal composite ultrathin strips, and relatively high production costs. Summary of the Invention

[0004] In view of this, the present invention provides a grinding-free preparation process and application for ultra-thin bilayer metal composite strips. The grinding-free preparation process of the present invention eliminates the need for surface grinding of the material, greatly simplifying the production process and improving production efficiency. Simultaneously, the composite material interface prepared by the present invention exhibits a regularly distributed array of pits, which not only enhances the bonding strength of the composite interface but also endows the material with excellent hydrophobicity, reduced heat transfer, reduced air resistance, and reduced electromagnetic wave reflection and scattering properties, giving it unique advantages in high-end fields such as aerospace and electronics industries, and promising promising application prospects.

[0005] The polishing-free fabrication process for the double-layer metal composite ultrathin strip of the present invention includes the following steps:

[0006] S1. Precisely cut an ultra-thin metal strip to obtain a metal substrate;

[0007] S2. Perform pre-rolling annealing on the metal substrate;

[0008] S3. Clean the metal substrate after pre-rolling annealing;

[0009] S4. After the cleaned metal substrate is stacked together, it is rolled by both texturized rolls and traditional flat rolls.

[0010] S5. After rolling, post-rolling annealing and cooling are performed to obtain a double-layer metal composite ultra-thin strip.

[0011] Preferably, the ultra-thin metal strip is any two of copper foil, titanium foil, and alloy strip. More preferably, the alloy strip is stainless steel strip.

[0012] Preferably, the pre-rolling annealing temperature is 500℃~950℃, and the holding time is 5~10min.

[0013] Preferably, the texturized roll is bonded to a metal substrate with high hardness, while the conventional flat roll is bonded to a metal substrate with low hardness.

[0014] Preferably, the rolling force is 7-12 kN and the rolling speed is 0.1 m / min.

[0015] Preferably, the post-rolling annealing temperature is 650℃~850℃, and the holding time is 3~10min.

[0016] The present invention also provides an application of a double-layer metal composite ultrathin strip in the aerospace and electronics industries, wherein the double-layer metal composite ultrathin strip is the double-layer metal composite ultrathin strip described in the above technical solution.

[0017] Compared with existing technologies, the preparation process of this invention only requires oil removal from the surface of the rolled piece, eliminating the tedious grinding process on the surfaces to be laminated. This not only greatly simplifies the production process but also fundamentally improves the overall production efficiency of double-layer metal composite ultra-thin strips. Furthermore, this invention enables the rolling composite of various metal strip substrates at a lower reduction rate, breaking the stringent limitations of traditional processes on materials and reduction rates, and opening up a wider range of applications for the preparation of ultra-thin strip composite materials. Finally, the composite material interface prepared by this invention exhibits a regularly distributed pit array structure. This unique structure not only significantly improves the bonding strength of the composite interface but also endows the material with excellent hydrophobicity, reduced heat transfer, reduced air resistance, and reduced electromagnetic wave reflection and scattering properties, giving it unique advantages in high-end fields such as aerospace and electronics, and promising promising application prospects. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Figure 1 The image shows the three-dimensional contour of the double-layer metal composite ultrathin strip in Example 1, where a and b are the copper foil side protrusions and c and d are the 304 stainless steel side depressions.

[0020] Figure 2 This is a SEM image of the surface of the rolled piece on one side of the double-layer metal composite ultra-thin strip bonded to the texturized roll in Example 1.

[0021] Figure 3 The texturized roll (bottom) and the conventional flat roll (top) used in this invention;

[0022] Figure 4 This is a three-dimensional contour image of the surface of the texturized roll used in this invention;

[0023] Figure 5 This is a schematic diagram of the rolling process;

[0024] Figure 6 This is a schematic diagram of the surface structure of the texturized roll;

[0025] Explanation of reference numerals in the attached drawings: 1. Traditional flat roll; 2. Low-hardness metal substrate; 3. High-hardness metal substrate; 4. Textured roll. Detailed Implementation

[0026] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] This invention provides a polishing-free fabrication process for ultra-thin double-layer metal composite strips, comprising the following steps:

[0028] S1. Precisely cut an ultra-thin metal strip to obtain a metal substrate;

[0029] S2. Perform pre-rolling annealing on the metal substrate;

[0030] S3. Clean the metal substrate after pre-rolling annealing;

[0031] S4. After the cleaned metal substrate is stacked together, it is rolled by both texturized rolls and traditional flat rolls.

[0032] S5. After rolling, post-rolling annealing and cooling are performed to obtain a double-layer metal composite ultra-thin strip.

[0033] The first step of this invention is to precisely cut an ultra-thin metal strip to obtain a metal substrate. Specifically, a metal material is selected as the composite metal substrate, and through precise cutting, the dimensions of each substrate are ensured to meet the preset standards, providing a good foundation for the subsequent composite process.

[0034] In some specific embodiments of the present invention, the ultra-thin metal strip is preferably any two of copper foil, titanium foil, and alloy strip. In other specific embodiments of the present invention, the alloy strip is preferably stainless steel strip. In some preferred embodiments of the present invention, the stainless steel strip is preferably 304 stainless steel strip. The metal substrate in the present invention is not limited to a single material, but innovatively uses a combination of dissimilar materials. Furthermore, when the composite of two ultra-thin strips is involved, the grinding-free preparation process of the present invention is not limited by the thickness of the metal substrate. This is because the present invention can select texturing rolls with different roughnesses according to the metal substrate of different thicknesses to ensure that the two metal substrates can form a good interfacial bond during the rolling process, thereby realizing the preparation of a double-layer metal composite ultra-thin strip.

[0035] The second step of this invention is to perform pre-rolling annealing on the cut metal substrate. The pre-rolling annealing is carried out in an inert gas atmosphere, and the preferred pre-rolling annealing temperature is 500℃~950℃, with a preferred holding time of 5~10 min. In some preferred embodiments of this invention, the inert gas is argon; when the metal substrate is stainless steel, the preferred pre-rolling annealing temperature is 950℃, and the preferred holding time is 5 min; when the metal substrate is copper foil, the preferred pre-rolling annealing temperature is 500℃, and the preferred holding time is 10 min; when the metal substrate is titanium foil, the preferred pre-rolling annealing temperature is 600℃, and the preferred holding time is 10 min.

[0036] This invention optimizes the internal microstructure of the material through pre-rolling annealing and prevents oxidation of the material during the annealing process by controlling the atmosphere.

[0037] The third step of this invention is to clean the metal substrate after pre-rolling annealing. In some specific embodiments of this invention, cleaning is performed using anhydrous ethanol and / or lint-free paper. This invention effectively removes impurities, oil stains, and other contaminants from the material surface by cleaning the metal substrate after pre-rolling annealing, facilitating subsequent rolling.

[0038] The fourth step of this invention involves stacking the cleaned metal substrates together and then rolling them using both a texturing roll and a conventional flat roll. In some specific embodiments of this invention, the texturing roll is applied to a metal substrate with high hardness, while the conventional flat roll is applied to a metal substrate with low hardness. The two substrates are then fed into a flat roll mill for composite rolling. The surface roughness of the texturing roll is preferably 5–50 μm. In some specific embodiments of this invention, the rolling force is 7–12 kN, and the rolling speed is 0.1 m / min. However, this invention does not strictly limit the surface roughness of the texturing roll; different specifications of texturing rolls can be customized according to specific requirements to ensure the uniformity and consistency of the surface pit array structure of the double-layer metal composite ultra-thin strip. Generally, the thicker the strip, the greater the surface roughness of the corresponding texturing roll should be to form an ideal pit array structure.

[0039] The fifth step of this invention is to perform post-rolling annealing. In some specific embodiments of this invention, the post-rolling annealing temperature is preferably 650℃~850℃, and the holding time is preferably 3~10min.

[0040] The metal composite material obtained in step 4 is subjected to post-rolling annealing, which is carried out in an inert gas atmosphere. In some preferred embodiments of the present invention, the inert gas is argon.

[0041] This invention prevents the material from oxidizing during the annealing process by controlling the annealing atmosphere after rolling.

[0042] This invention also provides an application of a double-layer metal composite ultrathin strip in the fields of aerospace, electronics industry, and petrochemical industry, wherein the double-layer metal composite ultrathin strip is the double-layer metal composite ultrathin strip described in the above technical solution.

[0043] The double-layer metal composite ultrathin strip of this invention features a recessed array structure and can be used as a coating material for the surface of aircraft (such as airplanes, rockets, satellites, etc.). The regular recessed array structure of the double-layer metal composite ultrathin strip of this invention reduces air resistance and improves flight efficiency. Simultaneously, the recessed array structure enhances the material's hydrophobic properties, helping to prevent fuselage icing and ensuring flight safety. In the thermal protection systems of aerospace vehicles, the double-layer metal composite ultrathin strip of this invention can be used as a component of heat insulation layers or heat-resistant tiles; its regular structure and hydrophobic properties help reduce heat transfer and protect internal structures from high-temperature damage. Furthermore, the double-layer metal composite ultrathin strip of this invention can be used as a coating material for the surface of automobile bodies, reducing air resistance during driving and improving fuel efficiency. Its hydrophobic properties also help prevent water accumulation on the vehicle body, reducing corrosion and wear. In radar and communication systems, the double-layer metal composite ultrathin strip of this invention can be used as a material for radomes; the regular recessed array structure helps reduce electromagnetic wave reflection and scattering, improving signal transmission quality.

[0044] To further illustrate the present invention, the following embodiments are provided for detailed description. All raw materials used in the following embodiments of the present invention are commercially available.

[0045] Unless otherwise specified, all experiments were repeated three times, and the results are expressed as averages.

[0046] Example 1: A polishing-free preparation process for an ultra-thin copper / 304 stainless steel composite strip, the steps of which are as follows:

[0047] S1. Precisely cut copper foil with a thickness of 20μm and 304 stainless steel ultra-thin strip with a thickness of 20μm as composite metal substrates. The specifications of the substrates are both 130mm×15mm.

[0048] S2. Place the cut copper foil and 304 stainless steel ultra-thin strip into the annealing furnace respectively, and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of 304 stainless steel is 950℃ and the holding time is 5min. The pre-rolling annealing temperature of copper foil is 500℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0049] S3. Gently wipe the surfaces of the copper foil and 304 stainless steel ultra-thin strip to be laminated with lint-free paper to remove any oil and impurities that may be present.

[0050] S4. The treated 304 stainless steel ultra-thin strip is tightly bonded to a roughened roll with a roughness of 15μm, and the copper foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 12kN and a rolling speed of 0.1m / min to obtain a composite ultra-thin strip.

[0051] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 850℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain a copper / 304 stainless steel composite ultrathin strip.

[0052] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0053] Example 2: A polishing-free preparation process for an ultra-thin copper / 304 stainless steel composite strip, the steps of which are as follows:

[0054] S1. Precisely cut copper foil with a thickness of 20μm and 304 stainless steel ultra-thin strip with a thickness of 10μm as composite metal substrates. The specifications of the substrates are both 130mm×15mm.

[0055] S2. Place the cut copper foil and 304 stainless steel ultra-thin strip into the annealing furnace respectively, and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of 304 stainless steel is 950℃ and the holding time is 5min. The pre-rolling annealing temperature of copper foil is 500℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0056] S3. Gently wipe the surfaces of the copper foil and 304 stainless steel ultra-thin strip to be laminated with lint-free paper to remove any oil and impurities that may be present.

[0057] S4. The treated 304 stainless steel ultra-thin strip is tightly bonded to a roughened roll with a roughness of 10μm, and the copper foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 8kN and a rolling speed of 0.1m / min to obtain a composite ultra-thin strip.

[0058] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 850℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain a copper / 304 stainless steel composite ultrathin strip.

[0059] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0060] Example 3: A polishing-free preparation process for an ultra-thin titanium / 304 stainless steel composite strip, the steps of which are as follows:

[0061] S1. Precisely cut titanium foil with a thickness of 20μm and 304 stainless steel ultra-thin strip with a thickness of 20μm as composite metal substrates. The specifications of the substrates are both 130mm×15mm.

[0062] S2. Place the cut titanium foil and 304 stainless steel ultra-thin strip into an annealing furnace and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of 304 stainless steel is 950℃ and the holding time is 5min. The pre-rolling annealing temperature of titanium foil is 600℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0063] S3. Gently wipe the surface of the titanium foil and 304 stainless steel ultra-thin strip to be laminated with a lint-free paper to remove any oil and impurities that may be present.

[0064] S4. The treated 304 stainless steel ultra-thin strip is tightly bonded to a roughened roll with a roughness of 15μm, and the titanium foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 10kN and a rolling speed of 0.1m / min to obtain a composite ultra-thin strip.

[0065] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 650℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain titanium / 304 stainless steel composite ultrathin strip.

[0066] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0067] Example 4: A grinding-free preparation process for an ultra-thin titanium / 304 stainless steel composite strip, the steps of which are as follows:

[0068] S1. Precisely cut titanium foil with a thickness of 20μm and 304 stainless steel ultra-thin strip with a thickness of 10μm as composite metal substrates. The specifications of the substrates are both 130mm×15mm.

[0069] S2. Place the cut titanium foil and 304 stainless steel ultra-thin strip into an annealing furnace and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of 304 stainless steel is 950℃ and the holding time is 5min. The pre-rolling annealing temperature of titanium foil is 600℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0070] S3. Gently wipe the surface of the titanium foil and 304 stainless steel ultra-thin strip to be laminated with a lint-free paper to remove any oil and impurities that may be present.

[0071] S4. The treated 304 stainless steel ultra-thin strip is tightly bonded to a roughened roll with a roughness of 10μm, and the titanium foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 8kN and a rolling speed of 0.1m / min to obtain a composite ultra-thin strip.

[0072] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 650℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain titanium / 304 stainless steel composite ultrathin strip.

[0073] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0074] Example 5: A polishing-free fabrication process for an ultrathin titanium / copper composite strip, the steps of which are as follows:

[0075] S1. Precisely cut titanium foil with a thickness of 20μm and copper foil with a thickness of 20μm as composite metal substrates, the specifications of the substrates are both 130mm×15mm;

[0076] S2. Place the cut titanium foil and copper foil into an annealing furnace and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of copper foil is 500℃ and the holding time is 10min. The pre-rolling annealing temperature of titanium foil is 600℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0077] S3. Gently wipe the surfaces of the titanium foil and copper foil to be laminated with lint-free paper to remove any oil and impurities that may be present.

[0078] S4. The treated titanium foil is tightly bonded to a roughened roll with a roughness of 15μm, and the copper foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 7kN and a rolling speed of 0.1m / min to obtain a composite ultrathin strip.

[0079] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 650℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain the titanium / copper steel composite ultrathin strip.

[0080] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0081] Example 6: A polishing-free fabrication process for an ultrathin titanium / copper composite strip, the steps of which are as follows:

[0082] S1. Precisely cut titanium foil with a thickness of 10μm and copper foil with a thickness of 20μm as composite metal substrates, the specifications of the substrates are both 130mm×15mm;

[0083] S2. Place the cut titanium foil and copper foil into an annealing furnace and perform pre-rolling annealing under argon protection. The pre-rolling annealing temperature of copper foil is 500℃ and the holding time is 10min. The pre-rolling annealing temperature of titanium foil is 600℃ and the holding time is 10min. After annealing, the materials are cooled to room temperature with the furnace.

[0084] S3. Gently wipe the surfaces of the titanium foil and copper foil to be laminated with lint-free paper to remove any oil and impurities that may be present.

[0085] S4. The treated titanium foil is tightly bonded to a roughened roll with a roughness of 10μm, and the copper foil is bonded to a smooth flat roll. The two materials are stacked together and rolled into a composite with a rolling force of 7kN and a rolling speed of 0.1m / min to obtain a composite ultrathin strip.

[0086] S5. The composite ultrathin strip is placed in an annealing furnace and subjected to post-rolling annealing under argon protection. The post-rolling annealing temperature is 650℃ and the holding time is 3min. After the heat treatment is completed, the material is cooled to room temperature with the furnace to obtain the titanium / copper composite ultrathin strip.

[0087] Replacing the texturized rolls with smooth flat rolls makes composite processing impossible.

[0088] Test Example 1

[0089] The properties of the composite ultrathin strips obtained in Examples 1-5 were tested, and the results are shown in Table 1.

[0090] Table 1 Performance test results of composite ultrathin strip

[0091]

[0092] As shown in Table 1, the composite ultrathin strips of this invention exhibit good electrical and thermal conductivity. The electrical conductivity of the steel-titanium composite ultrathin strip is lower than that of the copper-steel and copper-titanium composite ultrathin strips, but its mechanical properties are superior. The electrical conductivity of the steel-titanium composite ultrathin strip is lower than that of the copper-steel and copper-titanium composite ultrathin strips, but its mechanical properties are superior. The copper-titanium composite ultrathin strip has excellent electrical and thermal conductivity, and its mechanical properties are lower than those of the steel-titanium composite ultrathin strip but better than those of the copper-steel composite ultrathin strip. Therefore, the electrical conductivity of the composite ultrathin strip decreases with decreasing thickness, while the thermal conductivity decreases with increasing thickness. The ranking of electrical conductivity for composite ultrathin strips of different materials is copper-steel > copper-titanium > steel-titanium, and the ranking of thermal conductivity is copper-titanium > copper-steel > steel-titanium.

[0093] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A process for the preparation of a double-layer metal composite ultrathin strip without grinding, characterized in that, The method comprises the following steps: S1, precisely cutting a metal ultra-thin strip to obtain a metal base material; S2, pre-rolling annealing the metal base material; S3, cleaning the metal base material after pre-rolling annealing; S4, folding and stacking the cleaned metal base material, and then rolling by using a roughing roller and a traditional flat roller; S5, after rolling, post-rolling annealing, cooling, and obtaining a double-layer metal composite ultra-thin strip; The pre-rolling annealing is carried out in an inert gas atmosphere, the temperature is 500-950 DEG C, and the holding time is 5-10 min; The post-rolling annealing is carried out in an inert gas atmosphere, the temperature is 650-850 DEG C, and the holding time is 3-10 min; The roughing roller is attached to a metal base material with high hardness, and the traditional flat roller is attached to a metal base material with low hardness.

2. The manufacturing process according to claim 1, characterized in that, The metal ultra-thin strip is any two of a copper foil, a titanium foil and an alloy strip.

3. The manufacturing process of claim 2, wherein, The alloy strip is a stainless steel strip.

4. The manufacturing process of claim 1, wherein, The rolling force of the rolling is 7-12 kN, and the rolling speed is 0.1 m / min.

5. The use of a double-layer metal composite ultrathin strip in the aerospace and electronics industries, characterized in that, The double-layer metal composite ultra-thin strip is prepared by the process of any one of claims 1-4.

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