A PVD / CVD composite aluminum strip corrosion-resistant treatment process

Abstract

This invention belongs to the field of aluminum strip surface treatment technology, specifically relating to a PVD / CVD composite aluminum strip corrosion-resistant treatment process. This invention aims to solve the problem that existing aluminum strip surface treatment processes struggle to simultaneously maintain both surface corrosion resistance and forming toughness. The invention first involves self-sputtering the aluminum strip in a vacuum chamber to obtain an Al-Cr diffusion layer, followed by a PVD deposition stage to obtain a corrosion-resistant functional layer. The PVD-deposited aluminum strip then undergoes a co-deposition process to obtain a hybrid composite layer. Subsequently, a CVD deposition process is performed to obtain a CVD-deposited layer. After the CVD deposition process, the aluminum strip undergoes an oxygen-free post-treatment to obtain a hydrophobic layer. The aluminum strip treated with the corrosion-resistant process provided by this invention exhibits excellent surface corrosion resistance and forming toughness.

Description

Technical Field

[0001] This invention belongs to the field of aluminum strip surface treatment technology, specifically relating to a PVD / CVD composite aluminum strip corrosion-resistant treatment process. Background Technology

[0002] Due to its excellent specific strength, aluminum alloy has become one of the core materials for achieving lightweighting in new energy vehicles. This type of material is widely used in key components such as body structural parts, battery pack housings, and chassis suspension systems. However, as service environments become more extreme, such as hot and humid marine climates, roads containing de-icing agents, and the instantaneous high-temperature shocks caused by battery thermal runaway, extremely stringent requirements are being placed on the corrosion resistance and mechanical strength of aluminum alloy surfaces.

[0003] Currently, surface treatment of aluminum alloys mainly relies on deposition technologies such as PVD and CVD. However, while traditional PVD technology produces high-hardness coatings, it carries a fatal electrochemical risk. The electrode potential difference between Ti and Al means that if microscopic pinholes exist in the coating, the Ti coating will act as a cathode, accelerating pitting corrosion of the aluminum substrate. On the other hand, although the surface layer constructed by traditional CVD technology has a low coefficient of friction, its extremely high internal stress makes the coating prone to brittle fracture and detachment during flexible aluminum strip winding or large deformation processing. Therefore, the surface treatment process for aluminum strips needs to simultaneously ensure corrosion resistance, high strength, and excellent formability, posing significant technical challenges to existing aluminum strip processing methods.

[0004] To address the problem that existing aluminum strip surface treatment processes cannot simultaneously maintain the surface corrosion resistance and forming toughness of aluminum strips, a PVD / CVD composite aluminum strip corrosion resistance treatment process is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a PVD / CVD composite corrosion-resistant treatment process for aluminum strip. The invention first involves feeding the aluminum strip into a vacuum chamber for self-sputtering treatment to obtain an Al-Cr diffusion layer, followed by a PVD deposition stage to obtain a corrosion-resistant functional layer. The aluminum strip after the PVD deposition stage undergoes a co-deposition process to obtain a hybrid composite layer. Subsequently, a CVD deposition process is performed to obtain a CVD deposited layer. After the CVD deposition process is completed, the aluminum strip undergoes an oxygen-free post-treatment process to obtain a hydrophobic layer. After the treatment process, the surface of the aluminum strip sequentially comprises: an Al-Cr diffusion layer, a corrosion-resistant functional layer, a hybrid composite layer, a CVD deposited layer, and a hydrophobic layer.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A PVD / CVD composite corrosion-resistant treatment process for aluminum strip includes the following steps:

[0008] The aluminum strip moves at a speed of 1.2 m / min throughout the entire production line section.

[0009] The aluminum strip is fed into a vacuum chamber for self-sputtering treatment, specifically: after ignition in an argon atmosphere, it is held for 5 × 10⁻⁶ seconds. -3 A vacuum level below Pa. With the Cr target activated, the peak power is 1.6 kW / cm². 2 The pulse bias voltage was -800V, the processing frequency was 50Hz, the duty cycle was 5%, and no other working gas was introduced. After processing for 60-90 seconds, the self-sputtering process was completed, and an Al-Cr diffusion layer was obtained.

[0010] The self-sputtered aluminum ribbon was fed into the PVD deposition stage. Specifically, the operation was carried out in a mixed atmosphere of argon and nitrogen, with a peak power of 1.2 kW / cm². 2 The duty cycle was 4%, the working gas pressure was maintained at 0.5 Pa, and the substrate bias was -100 V. Both Cr and Al targets were used for co-sputtering. The pulse frequency was adjusted as follows: In the first condition, both the Cr and Al targets used a working frequency of 500 Hz for 15 seconds; in the second condition, the Cr target maintained a working frequency of 500 Hz, and the Al target used a working frequency of 50 Hz for 5 seconds. The first and second conditions were alternated, with a total deposition time of 15-20 minutes, resulting in a corrosion-resistant functional layer with a target thickness of 1.0-1.5 μm.

[0011] After the PVD deposition stage is completed, the duty cycle of the PVD deposition stage is linearly reduced to 0% within 30-45 seconds, while the HMDSO gas flow rate is linearly increased to 500 sccm for co-deposition. During co-deposition, only 100 sccm of argon gas is introduced as a protective gas; nitrogen gas is not introduced. During this process, the PVD target transitions from maintaining a glow discharge state to complete shutdown, while the HMDSO gas flow rate increases from 0 to a constant flow rate, resulting in a hybrid composite layer with a target thickness of 50-80 nm. HMDSO is introduced using a bubbling method, with argon as the carrier gas, and the bubbling temperature is 120℃.

[0012] After the co-deposition process is completed, the HMDSO gas flow rate is maintained at 500 sccm for the CVD deposition process. Specifically, oxygen is pulsed inlet while maintaining a constant HMDSO flow rate for 20 seconds at a flow rate of 3000 sccm and a plasma power of 2000 W. Then, the oxygen inlet is cut off for 10 seconds while maintaining a plasma power of 800 W, constituting one pulse cycle. This pulse cycle is repeated 25-30 times, achieving a target CVD deposition layer thickness of 1.0-1.2 μm.

[0013] After the CVD deposition process is completed, oxygen supply is stopped for an oxygen-free post-treatment process. The HMDSO flow rate is maintained at 500 sccm, the operating gas pressure is increased to 10-15 Pa, the power supply is reduced to 200 W, and after 2 min of treatment, a hydrophobic layer is obtained with a target hydrophobic layer thickness of 100-200 nm.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. Before depositing the coating, argon gas is not introduced; instead, HiPIMS self-sputtering is performed directly through a Cr target, allowing Cr elements to bombard the aluminum strip surface with extremely high kinetic energy. Under high bias voltage, the oxide film on the aluminum strip surface is removed, and Cr elements also form an Al-Cr diffusion layer on the aluminum strip surface. This step provides chemically active bonding points for subsequent coating growth, thereby effectively preventing the coating from peeling off from the substrate during large deformation of the aluminum strip during stamping.

[0016] 2. In the PVD deposition stage, dual-target sputtering is employed. By adjusting the pulse frequency and duty cycle, Cr and Al elements, due to their differences in flight velocity and ionization rate, form alternating CrN-enriched and CrAlN-enriched layers at the nanoscale. The interlayer interface between the CrN-enriched and CrAlN-enriched layers effectively hinders dislocation slip, and the plastic deformation capability of the CrAlN-enriched layer partially absorbs stamping stress. This constructs a complete corrosion-resistant functional layer while providing high-hardness mechanical support for subsequent CVD deposition.

[0017] 3. At the end of the PVD deposition stage, the operating power is reduced and CVD precursor spraying and ion source are initiated, but oxygen is not introduced for co-deposition. In this stage, Cr, Al, and organosilicon components coexist in the gas phase, forming a hybrid composite layer of CrAlSiCN components on the surface of the corrosion-resistant functional layer through plasma interaction. This composite layer structure effectively eliminates the physical interface between the PVD and CVD deposited layers. Subsequently, pulsed oxygen is introduced for the CVD deposition process, forming a multi-layered composite structure that effectively releases the interfacial stress of the corrosion-resistant functional layer and significantly improves the corrosion resistance of the aluminum strip surface.

[0018] 4. At the end of the CVD deposition process, a low-power, high-pressure oxygen-free post-treatment process is employed to retain the methyl functional groups in the precursor oriented towards the surface. This imparts extremely low surface energy to the coating surface, effectively reducing the coefficient of friction of the aluminum strip surface and improving hydrophobicity, thus forming a hydrophobic layer. Without introducing additional coatings, structural optimization of the aluminum strip surface's salt and corrosion resistance is achieved, while simultaneously providing effective physical protection for other functional layers, improving the durability of the aluminum strip in environments such as high salt spray. Attached Figure Description

[0019] Figure 1 This is a flowchart of the corrosion-resistant treatment process for PVD / CVD composite aluminum strip in this invention. Detailed Implementation

[0020] The technical solution of the present invention will be clearly and completely described below through some embodiments and experimental examples. 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.

[0021] Reference Figure 1 The process flow diagram shown illustrates that this invention provides a PVD / CVD composite corrosion-resistant treatment process for aluminum strips, with the technical solution as follows:

[0022] Example 1

[0023] The aluminum strip operates at a speed of 1.2 m / min throughout the entire production line. The aluminum strip width is 2100 mm, and the grade is 6061.

[0024] The aluminum strip is fed into a vacuum chamber for self-sputtering treatment, specifically: after ignition in an argon atmosphere, it is held for 5 × 10⁻⁶ seconds. -3 A vacuum level below Pa. With the Cr target activated, the peak power is 1.6 kW / cm². 2 The pulse bias voltage was -800V, the processing frequency was 50Hz, the duty cycle was 5%, and no working gas was introduced. After 60 seconds of processing, the self-sputtering process was completed, and an Al-Cr diffusion layer was obtained.

[0025] The self-sputtered aluminum ribbon was fed into the PVD deposition stage. Specifically, the operation was carried out in a mixed atmosphere of argon and nitrogen, with a peak power of 1.2 kW / cm². 2 The duty cycle was 4%, the working gas pressure was maintained at 0.5 Pa, and the substrate bias was -100 V. A Cr target and an Al target were used for co-sputtering. The pulse frequency was adjusted as follows: In the first condition, both the Cr and Al targets used a working frequency of 500 Hz for 15 seconds; in the second condition, the Cr target maintained a working frequency of 500 Hz, and the Al target used a working frequency of 50 Hz for 5 seconds. The first and second conditions were alternated, with a total deposition time of 15 minutes, resulting in a corrosion-resistant functional layer.

[0026] After the PVD deposition stage is completed, the duty cycle of the PVD deposition stage is linearly reduced to 0% within 30 seconds, and the HMDSO gas flow rate is linearly increased to 500 sccm for co-deposition. During co-deposition, only 100 sccm of argon gas is introduced as a protective gas, and nitrogen gas is not introduced. During this process, the PVD target goes from maintaining a glow discharge state to being completely shut off, while the HMDSO gas flow rate increases from 0 to a constant flow rate, resulting in a hybrid composite layer.

[0027] After the co-deposition process is completed, the HMDSO gas flow rate is maintained at 500 sccm for the CVD deposition process. Specifically, oxygen is pulsed inlet while maintaining a constant HMDSO flow rate for 20 seconds at a flow rate of 3000 sccm and a plasma power of 2000 W. Then, the oxygen inlet is cut off for 10 seconds while maintaining a plasma power of 800 W, constituting one pulse cycle. This pulse cycle is repeated 25 times.

[0028] After the CVD deposition process is completed, oxygen supply is stopped for an anaerobic post-treatment process. The HMDSO flow rate is maintained at 500 sccm, the operating gas pressure is increased to 10 Pa, the power supply is reduced to 200 W, and after 2 min of treatment, a hydrophobic layer is obtained.

[0029] Examples 2-16 differ from Example 1 in operating parameters, but the other process steps and the range of raw material selection are the same.

[0030] The specific changes in operating parameters are summarized in Table 1.

[0031] Table 1. Changes in operating parameters in Examples 1-16

[0032]

[0033] Comparative Example 1

[0034] Unlike Example 1, 100 sccm of argon gas was introduced during the self-sputtering process, while all other process parameters remained the same.

[0035] Comparative Example 2

[0036] Unlike Example 1, the bias voltage for the self-sputtering process was adjusted to -400V, while all other process parameters remained the same.

[0037] Comparative Example 3

[0038] Unlike Example 5, only the first operating condition was used in the PVD deposition stage, while all other process parameters remained the same.

[0039] Comparative Example 4

[0040] Unlike Example 5, only the second operating condition was used in the PVD deposition stage, while all other process parameters remained the same.

[0041] Comparative Example 5

[0042] Unlike Example 5, in the PVD deposition stage, the holding time for the first condition was changed to 60s, and the holding time for the second condition was changed to 20s, while the total deposition time remained unchanged, and all other process parameters were the same.

[0043] Comparative Example 6

[0044] Unlike Example 9, no co-deposition process was performed. After the PVD deposition stage, the CVD deposition process was performed directly, and all other process parameters were the same.

[0045] Comparative Example 7

[0046] Unlike Example 9, during the CDV deposition process, the oxygen flow rate was maintained at 3000 sccm, the plasma power was 2000 W, there was no stage of cutting off the oxygen supply, the total deposition time remained unchanged, and other process parameters were the same.

[0047] Comparative Example 8

[0048] Unlike Example 9, the duty cycle of the PVD deposition stage was directly adjusted to 0% during the co-deposition process, and the flow rate of HMDSO gas was linearly increased to 500 sccm, while other process parameters remained the same.

[0049] Comparative Example 9

[0050] Unlike Example 13, no oxygen-free post-treatment process was performed, but all other process parameters remained the same.

[0051] Comparative Example 10

[0052] Unlike Example 13, the oxygen flow rate was maintained at 200 sccm during the anaerobic post-treatment process, which was actually an aerobic post-treatment process, while other process parameters remained the same.

[0053] Experimental Example 1

[0054] The film adhesion of the aluminum strips treated in Examples 1-4 and Comparative Examples 1-2 was tested, and the relevant results are summarized in Table 2.

[0055] The test method for film adhesion refers to the relevant test methods in GB / T 30707 standard. The test methods for ceramic coatings are also fully applicable to aluminum strip coatings. The initial failure load L of the treated aluminum strip is measured. C1 (N) and spalling load L C2 (N), the pressure head loading rate is 100N / min, the scratch length is 10mm, and the scratch rate is 10mm / min.

[0056] Table 2. Film adhesion of aluminum strips treated in Examples 1-4 and Comparative Examples 1-2

[0057]

[0058] As shown in Table 2, Examples 1 to 4 showed significantly higher initial failure load and peeling load than Comparative Example 1 and Comparative Example 2, indicating that the corrosion-resistant aluminum strips prepared in Examples 1 to 4 have a clear advantage in improving the adhesion between the film and the substrate.

[0059] Comparative Example 1 introduced argon gas during the self-sputtering process, which changed the bombardment environment of the pure metal plasma. The presence of argon ions caused a scattering effect that weakened the high kinetic energy of chromium ions, making it impossible for them to effectively break the oxide film on the aluminum strip surface and form a diffusion layer with sufficient depth, resulting in a significant decrease in adhesion. Comparative Example 2 adjusted the self-sputtering bias voltage to -400V, which greatly reduced the kinetic energy of the bombarding particles, making it impossible for chromium elements to obtain enough energy to penetrate the surface barrier and inject into the aluminum matrix lattice. This resulted in the inability to form an effective Al-Cr diffusion layer, and the film layer adhesion performance was the worst, which also proved the necessity of setting high bias voltage parameters.

[0060] In summary, this invention employs HiPIMS self-sputtering technology without introducing a working gas, combined with a high-pulse bias parameter design. These two elements produce a significant synergistic effect: the physical bombardment effect of the high-energy chromium ion beam completely removes the natural oxide film on the aluminum strip surface, while the high bias drives chromium atoms to be injected into the aluminum substrate to form an Al-Cr diffusion layer. The specific argon-free process environment and high-energy bias parameters jointly construct an atomic-level metallurgical bonding interface, providing chemically active connection anchors for the subsequent growth of corrosion-resistant functional layers. This maximizes the interfacial bonding strength, significantly improves the coating adhesion stability of the aluminum strip under large deformation conditions during stamping, and effectively prevents the coating from peeling off from the substrate while ensuring strong interfacial bonding.

[0061] Experiment Example 2

[0062] The surface nanohardness and toughness of the aluminum strips treated in Examples 5-8 and Comparative Examples 3-5 were tested, and the relevant results are summarized in Table 3.

[0063] The surface nanohardness test method is as follows: referring to the relevant test method of ASTM E2546 standard, the indentation depth is controlled to be ≤200nm, the load holding time is 10s, and the indenter loading rate is 0.05s. -1 The indenter was a triangular pyramidal diamond indenter with a face angle of 65.3°. After testing, the nanohardness (GPa) of the aluminum strip surface was calculated.

[0064] The toughness test method is as follows: Cut the aluminum strip into 90mm×90mm square pieces. Referring to the relevant test methods of GB / T 4156 standard, use a 20mm diameter hemispherical punch and feed at a constant rate of 10mm / min. When the first crack appears on the coating surface, record the punch penetration depth IE (mm). The greater the penetration depth, the better the toughness of the aluminum strip and its surface coating, and the better the processing performance.

[0065] Table 3. Surface nano-hardness and toughness of aluminum strips treated in Examples 5-8 and Comparative Examples 3-5

[0066]

[0067] As shown in Table 3, Examples 5 to 8 are superior to Comparative Examples 3, 4 and 5 in terms of surface nanohardness and indentation depth, indicating that the corrosion-resistant aluminum strips prepared in Examples 5 to 8 have significant advantages in balancing surface hardness and processing toughness.

[0068] Comparative Example 3 only used the first process condition for deposition, lacking the flexible buffer phase formed by the low-frequency aluminum target intervention, resulting in a significant decrease in indentation depth despite high coating hardness, which seriously affected processing toughness; Comparative Example 4 only used the second process condition for deposition, which greatly reduced the doping ratio of aluminum, resulting in a significant decrease in surface nano-hardness and an inability to provide effective mechanical support; Comparative Example 5 extended the holding time of both processes, changed the growth cycle and thickness of the alternating layer, and destroyed the nanoscale alternation effect, resulting in a difference in indentation depth compared to the examples, which also proved the rationality of the original process alternation time parameter setting.

[0069] In summary, this invention employs dual-target sputtering in the PVD deposition stage and utilizes pulse frequency adjustment to construct an alternating high- and low-frequency working mode. These two methods produce a significant synergistic effect: leveraging the difference in flight velocity and ionization rate between chromium and aluminum elements, alternating CrN-enriched layers and CrAlN-enriched layers are formed at the nanoscale. Specific frequency adjustment methods and time parameter control synergistically optimize the microstructure of the functional layer, utilizing the interlayer interface to hinder dislocation slip and enhance hardness. Simultaneously, the plastic deformation capability of the enriched layers absorbs stamping stress, maximizing mechanical properties and significantly improving the nanoscale hardness and toughness of the aluminum strip surface. While constructing a complete corrosion-resistant functional layer, it also provides high-hardness and excellent formability mechanical support for subsequent processes.

[0070] Experimental Example 3

[0071] The neutral salt spray resistance of the aluminum strips treated in Examples 9-12 and Comparative Examples 6-8 was tested. The results are summarized in Table 4.

[0072] The test method for neutral salt spray resistance refers to the relevant test method of ASTM B117 standard. A 5% sodium chloride solution is used as the salt spray, and the aluminum strip is subjected to corrosion test at 35°C. The time (in hours) when the first visible corrosion point appears in the center area of ​​the aluminum strip is recorded. The longer this time, the better the neutral salt spray resistance of the aluminum strip.

[0073] Table 4. Neutral salt spray resistance of the aluminum strips treated in Examples 9-12 and Comparative Examples 6-8

[0074]

[0075] As shown in Table 4, Examples 9 to 12 all had significantly longer times of first corrosion point appearance than Comparative Examples 6, 7 and 8, indicating that the corrosion-resistant aluminum strips prepared in Examples 9 to 12 have a significant advantage in improving neutral salt spray resistance.

[0076] Comparative Example 6 did not undergo a co-deposition process; CVD deposition was performed directly after PVD deposition. This resulted in a clear physical interface between the corrosion-resistant functional layer and the CVD deposited layer, lacking an effective chemical bonding transition. Consequently, corrosive media could easily penetrate along the interface, resulting in the worst corrosion resistance performance. Comparative Example 8 directly adjusted the PVD deposition duty cycle to zero during the co-deposition process, failing to form a smooth composition gradient. This resulted in the inability to effectively generate a uniform hybrid composite layer, affecting the interlayer bonding quality and overall corrosion resistance. Comparative Example 7 maintained a constant oxygen flow rate and plasma power during CVD deposition, failing to construct a multi-layered composite structure. The lack of a stress release mechanism and the barrier effect of the multi-layer interface led to a significantly shorter corrosion resistance time compared to the examples, further demonstrating the necessity of pulsed deposition technology.

[0077] In summary, this invention employs a co-deposition process with linear power reduction and precursor spraying at the end of PVD deposition, combined with a pulsed oxygen-introduced CVD deposition process. These two processes produce a significant synergistic effect: the co-deposition process utilizes the metal elements and organosilicon components present in the gas phase to generate a hybrid composite layer of CrAlSiCN components at the interface, effectively eliminating the physical interface; the pulsed CVD process constructs a multi-layer composite structure, effectively releasing interfacial stress and improving barrier properties. The specific co-deposition transition mode and pulsed deposition parameters synergistically optimize the interlayer structure and microstructure of the coating, maximizing interlayer bonding and barrier properties, significantly improving the neutral salt spray resistance of the aluminum strip surface, and providing durable corrosion protection for the aluminum strip while ensuring the stability of the coating structure.

[0078] Experiment Example 4

[0079] The surface friction coefficient and surface hydrophobicity of the aluminum strips treated in Examples 13-16 and Comparative Examples 9-10 were tested, and the relevant results are summarized in Table 5.

[0080] The surface friction coefficient was tested according to the ASTM G99 standard. A 6mm diameter GCr15 bearing steel ball was used as the grinding pair, the normal load was 5N, the sliding speed was 10cm / s, and the surface friction coefficient under steady state was recorded.

[0081] The test method for surface hydrophobicity is to directly measure the water contact angle.

[0082] Table 5. Surface friction coefficient and surface hydrophobicity of the aluminum strips treated in Examples 13-16 and Comparative Examples 9-10

[0083]

[0084] As shown in Table 5, Examples 13 to 16 are significantly better than Comparative Examples 9 and 10 in terms of surface friction coefficient and water contact angle, indicating that the corrosion-resistant aluminum strips prepared in Examples 13 to 16 have obvious advantages in reducing surface friction coefficient and improving surface hydrophobicity.

[0085] Comparative Example 9 did not undergo an oxygen-free post-treatment process, lacking the hydrophobic layer construction step. This resulted in a lack of directional arrangement of methyl functional groups on the aluminum strip surface, leading to a significant increase in the surface friction coefficient and a decrease in the water contact angle. Comparative Example 10 introduced oxygen during the oxygen-free post-treatment process, effectively turning it into an aerobic treatment. The presence of oxygen prevented the effective retention of methyl functional groups in the precursor, making it impossible to form a low surface energy structure on the surface. This resulted in the worst hydrophobic performance and the highest friction coefficient, further demonstrating the necessity of strictly controlling the oxygen-free environment during the post-treatment stage.

[0086] In summary, this invention employs low-power combined with high-pressure process conditions at the end of CVD deposition, and strictly adheres to an oxygen-free post-treatment operation that stops oxygen supply. These two factors produce a significant synergistic effect: the low-power and high-pressure environment effectively suppresses excessive disruption of the organic structure by the plasma, allowing the methyl functional groups in the precursor to be retained and aligned towards the surface. The specific oxygen-free environment setting and power and pressure parameters synergistically optimize the chemical structure of the coating surface, endowing the coating with extremely low surface energy, achieving structural optimization of surface properties, significantly reducing the coefficient of friction of the aluminum strip surface and improving hydrophobicity. Without introducing an additional coating, it provides effective physical protection for the aluminum strip and enhances its durability in harsh environments.

[0087] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A PVD / CVD composite corrosion-resistant treatment process for aluminum strip, characterized in that: The processing technology is as follows: An aluminum strip is fed into a vacuum chamber for self-sputtering treatment to obtain an Al-Cr diffusion layer. The aluminum strip, after the self-sputtering treatment, is fed into the PVD deposition stage. Under a mixed atmosphere of argon and nitrogen, the peak power is 1.2 kW / cm². 2 The duty cycle is 4%, the working gas pressure is maintained at 0.5 Pa, and the substrate bias voltage is -100 V. A Cr target and an Al target are used for co-sputtering. The pulse frequency is adjusted as follows: First condition: both the Cr and Al targets operate at 500 Hz for 15 seconds; Second condition: the Cr target maintains a 500 Hz operating frequency, and the Al target operates at 50 Hz for 5 seconds. The first and second conditions are alternated, with a total deposition time of 15-20 minutes, resulting in a corrosion-resistant functional layer. During the self-sputtering process, no process gas is introduced; only the Cr target is activated. The aluminum strip that has undergone the PVD deposition stage is subjected to a co-deposition process to obtain a hybrid composite layer; The aluminum strip that has undergone the co-deposition process is subjected to a CVD deposition process to obtain a CVD deposited layer; After the CVD deposition process is completed, the aluminum strip is subjected to an oxygen-free post-treatment process to obtain a hydrophobic layer. After the aforementioned processing, the surface of the aluminum strip sequentially comprises: the Al-Cr diffusion layer, the corrosion-resistant functional layer, the hybrid composite layer, the CVD deposition layer, and the hydrophobic layer.

2. The PVD / CVD composite corrosion-resistant treatment process for aluminum strip according to claim 1, characterized in that: During the co-deposition process, the duty cycle of the PVD deposition stage is linearly reduced to 0% within 30-45 seconds, and the flow rate of HMDSO gas is linearly increased to 500 sccm.

3. The PVD / CVD composite corrosion-resistant treatment process for aluminum strip according to claim 1, characterized in that: The CVD deposition process employs pulsed oxygen introduction, with a constant HMDSO flow rate, and the pulse cycle is performed 25-30 times.

4. The PVD / CVD composite corrosion-resistant treatment process for aluminum strip according to claim 1, characterized in that: During the anoxic post-treatment process, the HMDSO flow rate is kept equal to that during the CVD deposition process.

Images