Monitoring and monitoring method of chromium-free anodization sealing treatment

Abstract

The present application relates to monitoring and monitoring methods for chromium-free anodization sealing processes. A method for in-situ monitoring and optimization of a sealing process, the method comprising: sealing a surface of an anodized substrate, providing a test anodized substrate corresponding to the anodized substrate into the same sealing process as the anodized substrate, measuring an electrochemical surface potential of the test anodized substrate representative of a surface of the anodized component, collecting the electrochemical surface potential measurement data, analyzing the electrochemical surface potential measurement data, and identifying one or more performance indicators related to sealing quality and process parameters. The method can comprise: using information obtained from analyzing the electrochemical surface potential measurement data to optimize the sealing process, measuring the electrochemical surface potential using a potentiostat and a reference electrode, and measuring the electrochemical surface potential of the test anodized substrate representative of a surface of the anodized component.

Description

Technical Field

[0001] This teaching generally relates to the monitoring of anodized seal treatments, and more specifically, to the monitoring of chromium-free (VI) anodized seal treatments. Background Technology

[0002] With increasing interest in chemical sealing treatment of aluminum alloys after chromium-free (VI) anodizing, it is essential to define the operating parameters for this technology to meet treatment specifications. Similarly, monitoring these operating parameters can contribute to improved quality of the chemical sealing process. Traditional industry testing methods require at least two weeks to provide data and can only track relative performance. These known methods lack immediate, real-time data that provides mechanical information about the chemical sealing process. This data can be used to inform decisions regarding optimization of treatment parameters, which can be tailored to the treatment of any given aluminum alloy. This measurement method can also be used for chemical sealing tank maintenance, which can prevent downtime during production by ensuring the tanks remain compliant with treatment specifications through continuous monitoring and troubleshooting.

[0003] The current method for optimizing anodizing sealing processes involves conducting performance tests, adjusting processing parameters based on the data, and repeating the process as needed. This method only provides relative performance levels and does not offer any real-time data. Furthermore, each cycle requires two weeks or longer to generate data, and it does not provide any mechanical information regarding the seal-forming process.

[0004] Therefore, it is desirable to develop methods for providing real-time data that provides mechanical information about chemical sealing processes used in conjunction with aluminum processing and production processes. Summary of the Invention

[0005] To provide a basic understanding of some aspects of one or more embodiments of this teaching, a simplified overview is presented below. This invention is not intended as a broad overview, nor is it intended to identify key or critical elements of this teaching, nor to depict the scope of this disclosure. Rather, its primary purpose is merely to present one or more concepts in a simplified form as a prelude to the detailed description that follows.

[0006] A method for in-situ monitoring and optimization of sealing processes is disclosed. The method includes: sealing the surface of an anodized substrate; providing a test anodized substrate corresponding to the anodized substrate to the same sealing process as the anodized substrate; measuring the electrochemical surface potential of the test anodized substrate, representing the surface of the anodized component; collecting the electrochemical surface potential measurement data; analyzing the electrochemical surface potential measurement data; and identifying one or more performance indicators related to sealing quality and processing parameters. Other embodiments of this aspect may include corresponding computer systems, apparatuses, and computer programs recorded on one or more computer storage devices, each computer system, apparatus, and computer program configured to perform the actions of the method.

[0007] Implementations of methods for in-situ monitoring and optimization of sealing processes may include the following steps: optimizing the sealing process using information obtained from analytical electrochemical surface potential measurement data, and measuring the electrochemical surface potential using a potentiostat and a reference electrode. The methods for in-situ monitoring and optimization of sealing processes may include the following steps: measuring the electrochemical surface potential of a test anodized substrate representing the surface of an anodized component. Measuring the electrochemical surface potential of the corresponding test anodized substrate may include: measuring the open-circuit potential (OCP) of the corresponding test anodized substrate. The methods for in-situ monitoring and optimization of sealing processes may include the following steps: performing surface characterization on the corresponding test anodized substrate. Performing surface characterization may include: SEM / EDS cross-sectional imaging and glow discharge-photoemission spectroscopy (GDOES). Implementations of the described techniques may include hardware, methods or processes, or computer software on a computer-accessible medium.

[0008] A method for monitoring a sealing process is also disclosed. This method further includes the steps of: sealing the surface of an anodized substrate; transferring a test anodized substrate corresponding to the anodized substrate to the same sealing process as the anodized substrate; measuring the electrochemical surface potential of the test anodized substrate, representing the surface of the anodized component, in situ using open-circuit potential method to generate electrochemical surface potential data; and analyzing the electrochemical surface potential measurement data. Other embodiments of this aspect include corresponding computer systems, apparatuses, and computer programs recorded on one or more computer storage devices, each computer system, apparatus, and computer program configured to perform the actions of the method.

[0009] Implementation of this method may include the following steps: measuring the electrochemical surface potential of a test anodized substrate in a conversion coating bath. The electrochemical surface potential is measured using a potentiostat in combination with a reference electrode directly immersed in a sealing solution. The method may include the following steps: adjusting one or more parameters of the sealing process. The one or more parameters may include at least one selected from the group consisting of: sealing solution concentration, pH, temperature, deoxidation time, anodizing voltage, sealing duration, rinsing quality, and rinsing times. The method may include the following steps: characterizing the surface of the test anodized substrate using surface characterization methods. Surface characterization methods may include the following steps: glow discharge-photoemission spectroscopy (GDOES) in combination with open-circuit potential analysis to analyze elemental concentrations across a sealing layer depth profile from about 1 μm to about 150 μm. The substrate may include anodized aluminum or an aluminum alloy. Implementation of the described techniques may include hardware, methods or processes, or computer software on a computer-accessible medium.

[0010] A system for monitoring sealing processes is disclosed, the system including a potentiostat. The system also includes an electrochemical cell. The system further includes a reference electrode, wherein the reference electrode is immersed in a sealant solution to measure the open-circuit potential (OCP) of the interface between the anodized alloy surface and the sealant solution. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each computer system, apparatus, and computer program configured to perform actions of the method.

[0011] Implementations of a system for monitoring sealing processes may include a test panel made of anodized alloy, wherein a reference electrode is immersed in the vicinity of the test panel. The analyzed data is used to optimize processing parameters specific to the sealing process of the aluminum alloy substrate material. The reference electrode may include a standard calomel (SCE) type reference electrode. The anodized alloy may include aluminum. Implementations of the described techniques may include hardware, methods or processes, or computer software on a computer-accessible medium.

[0012] The features, functions, and advantages already discussed can be implemented independently in various implementations or combined in other implementations, further details of which can be seen in the following description. Attached Figure Description

[0013] Embodiments of the present teachings are illustrated in conjunction with the accompanying drawings, which are incorporated in and form part of this specification, and are used together with the description to explain the principles of this disclosure. In the figures:

[0014] Figure 1 (A) depicts the application of structural components including exemplary anodized and sealed substrates for use in aerospace vehicles. Figure 1 (B) is based on this disclosure. Figure 1 An exploded view of a portion of the aerospace vehicle of (A).

[0015] Figure 2 This is a flowchart illustrating a process for monitoring an exemplary chromium-free (VI) anodizing seal treatment according to the present disclosure.

[0016] Figure 3 This is a schematic diagram of an exemplary open-circuit potential monitoring setup according to this disclosure.

[0017] Figure 4 This is a graph showing the open circuit potential (OCP) profile according to this disclosure.

[0018] Figure 5 This is a schematic diagram of a sputtering arrangement for an exemplary glow discharge-photoemission spectroscopy (GDOES) measurement according to the present disclosure.

[0019] It should be noted that some details in the accompanying drawings have been simplified and drawn to facilitate understanding of this teaching, rather than to maintain strict structural accuracy, detail, and proportion. Detailed Implementation

[0020] Reference will now be made in detail to exemplary embodiments of this teaching, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals will be used throughout the drawings to refer to the same, similar, or analogous parts.

[0021] This disclosure provides real-time data that gives mechanical information about the chemical sealing process. This data can be used to inform decisions on optimizing processing parameters, which can be tailored for the processing of any given aluminum alloy. The methods and processes of this disclosure can also be used for the maintenance of chemical sealing tanks, which can prevent downtime during production by ensuring that the chemical sealing tanks remain in compliance with processing specifications through monitoring and troubleshooting.

[0022] This disclosure provides for in-situ measurement of the evolution of the electrochemical surface potential of a test specimen after anodizing a corresponding actual substrate or component undergoing a sealing process under full immersion conditions. Measurements can be performed using commercially available potentiostats, calomel reference electrodes, and electrochemical cells. Measurements are performed using test specimens of the solution of interest and relevant alloys (which have undergone any relevant pretreatment to make them a true representation of the corresponding component). Data can be analyzed using commercial electrochemical control and analysis software. The apparatus can be used with the method described herein, operating directly from the actual sealing solution obtained from the chemical treatment tank. Furthermore, the test sample can undergo comprehensive pretreatment on a treatment line corresponding to the actual component. Conventional use of this apparatus involves non-in-situ experiments using samples that have been fully treated prior to testing, and using test solutions representative of the operating environment (e.g., aqueous sodium chloride solution).

[0023] This teaching provides a method and tool for in-situ monitoring of the electrochemical sealing process after Cr(VI) anodizing to generate real-time data, comprising measuring the electrochemical surface potential of a test specimen during the sealing process under full immersion conditions after anodizing. Measurements are performed in a conversion coating bath or in an electrochemical cell using a potentiostat and a reference electrode. Data are analyzed using electrochemical control and analysis software. Open-circuit potential (OCP) monitoring provides: (1) optimization of processing parameters for any given aluminum substrate, and (2) troubleshooting in production chemical treatment baths.

[0024] The current method for optimizing exemplary anodized seal treatment involves processing test panels via a trench line and then placing them in a salt spray chamber for a two-week cycle. This method does not provide real-time data, only tracking relative performance across production batches or production time ranges. The current method involves performing this performance test and adjusting the treatment parameters based on the data, repeating the process as needed. Again, this method only provides a relative performance rating, and it does not provide any real-time data, as each cycle takes two weeks or longer to generate data, and it provides no mechanical information regarding the seal-forming process.

[0025] The methods and tools described herein can be used to monitor the performance of trivalent chromium conversion treatment in chemically sealed tank lines, providing real-time feedback. The described methods use industry-standard tests combined with open-circuit potential (OCP) measurements, time measurements, and surface characterization to build a database that allows OCP monitoring to be used as an independent performance indicator.

[0026] The selection and optimization of commercial off-the-shelf (COTS) Cr(VI)-free post-anodizing chemical sealing treatments for aluminum alloys suffers from the aforementioned drawbacks. Furthermore, the operating parameters of this technology must be defined for the treatment specifications. Traditional industry testing methods require at least two weeks to provide data and can only track relative performance. The proposed method provides immediate, real-time data, offering mechanical information about the chemical sealing process. This data can be used to inform decisions regarding the optimization of treatment parameters, which can be tailored for the treatment of any given aluminum alloy. The methods and tools described herein can also be used for the maintenance of chemical sealing tanks, which can prevent production downtime by ensuring that the chemical sealing tanks remain in compliance with treatment specifications through monitoring and troubleshooting.

[0027] This invention measures the evolution of the electrochemical surface potential of test specimens in situ during a sealing process under full immersion conditions after anodizing. During trivalent chromium treatment (TCP), a sealing process is used to seal the anodized surface to enhance corrosion protection of the anodized component. This is typically accomplished using hot water or a diluted hexavalent chromium sealant. The TCP seal forms a “cap” or encapsulation on and on the surface of the anodized layer, penetrating the porous anodized structure to a depth of up to approximately 1 micrometer. Within this depth, gradients of chromium, zinc, and potentially other components can be observed using energy-dispersive spectroscopy (EDS) of cross-sectional samples. Combined with OCP testing, as described herein, scanning electron microscopy (SEM) imaging can determine whether this occurs during a shorter sealing immersion time, in which case the corresponding OCP distribution will be sufficient to correlate performance. For example, OCP can then be correlated with penetration depth.

[0028] Measurements are performed using a commercially available potentiostat, calomel reference electrode, and electrochemical cell. Measurements are performed using a sealing solution of interest and test specimens of the relevant alloy that have undergone any relevant pretreatment, ensuring they are a true representation of the component. Data are analyzed using commercial electrochemical control and analysis software. The unique aspect of this device for the present invention is that it operates using an actual sealing solution obtained directly from the chemical treatment tank. Furthermore, the test sample undergoes comprehensive pretreatment on the treatment line. Typical treatments to date may include rinsing after cleaning, rinsing after deoxidation or etching steps, and rinsing after reanodic treatment. A sealing step is then performed, during which OCP monitoring occurs. The conventional use of this device is for in-situ experiments using samples that have been fully treated prior to testing, and using a test solution representative of the operating environment (e.g., an aqueous sodium chloride solution). Prior to open circuit potential (OCP) measurement, the test panel undergoes the following chemical tank line treatment steps at pilot or production scale, with the open circuit potential (OCP) measurement performed in an electrochemical cell containing a TCP seal.

[0029] The proposed method provides immediate mechanical information related to a single sealing treatment, unlike existing solutions which require multiple tests that only provide a performance rating relative to other treatment conditions. Existing solutions also require weeks to generate data and must be repeated until treatment optimization is achieved. Measurements are performed using a commercially available potentiostat, reference electrode, electrochemical cell, and electrochemical control and analysis software. Measurements are performed using the solution or treatment of interest. The test specimens used and any chemical pretreatments also represent the part to be treated and thus correspond to the part being treated.

[0030] Beyond processing optimization, the methods taught herein can be used to maintain the chemical and operational parameters of anodized seal tanks when implemented in chemical processing lines. These methods and processes can serve as tools for selecting parameters for specific alloys and addressing pretreatment issues for that material. The methods can be used for pilot-scale laboratory testing and for chemical processing line maintenance to provide immediate, real-time data that is used to inform decisions regarding the optimization of processing parameters associated with the processing of any given alloy. The methods can also provide cost savings by accelerating processing optimization and gaining an understanding of chemical seal processing for more robust decision-making, while ensuring that chemical processing tanks remain compliant with processing specifications through processing monitoring and troubleshooting. Production processes can be streamlined by adjusting processing times for specific alloys to minimize rework.

[0031] Anodizing and sealing processes involve cleaning panels or components using solvent wiping or other cleaning methods, followed by mounting for chemical bath line treatment. The mounted panels can then be sequentially immersed in a series of baths, remaining in each for a predetermined time. The processes associated with these baths are cleaning, deoxidation, anodizing, and sealing. Thorough rinsing is performed between each of these additional steps by immersion in specific rinsing baths associated with the previous treatments. The panels can then be air-dried at 160°F or below or dried in a heater. Various structural components and substrates that can be used in aerospace vehicles are treated in this manner to improve adhesion and corrosion resistance.

[0032] Figure 1 (A) depicts the application of structural components including exemplary anodized and sealed substrates for use in aerospace vehicles. Figure 1 (B) is based on this disclosure. Figure 1 An exploded view of a portion of an aerospace vehicle (A). The application of the methods of this disclosure is shown on an aerospace vehicle 100, whereby the vehicle substrate 130 is coated with the anodized and sealed substrate of this disclosure. Figure 1(B) shows an exploded view of a vehicle substrate 130 or its surface, with a substrate anodized layer 132 and a sealing layer 134 on the surface of the vehicle substrate 130 and / or on structural components of the vehicle or on a portion of the vehicle. In one example, the application of the coating composition of this disclosure is directed toward the outer surface of the aerospace vehicle 100. In the example, additional coatings (e.g., paint, coatings, or other protective coatings) may be applied to the anodized layer 132 and the sealing layer 134. While exemplary examples of the outer substrate or surface of the aerospace vehicle 100 are shown herein, they are intended as non-limiting examples. Other structural applications or areas may also exist in the aerospace vehicle 100 or other structures or vehicles in which anodized and sealed substrates may be used.

[0033] The substrate disclosed herein may include a metallic substrate, such as aluminum or its alloys, for example aluminum alloys from the 1000 series to up to the 8000 series (including the 8000 series).

[0034] Figure 2 This is a flowchart illustrating a process for monitoring an exemplary chromium-free (VI) anodizing seal treatment according to this disclosure. The method 200 for in-situ monitoring and optimization of the seal treatment includes a data collection phase 202, database formation and management, in-situ monitoring 214 of the open-circuit potential (OCP) during the production seal treatment, and an analysis and optimization phase 220 for the method 200 for in-situ monitoring and optimization of the seal treatment. During the data collection phase 202, when the surface of the anodized substrate is sealed in the production setting, a test anodized substrate corresponding to the anodized substrate is provided to the same seal treatment as the anodized substrate. The test anodized substrate is evaluated by: measuring the electrochemical surface potential or open-circuit potential of the anodized substrate representing the surface of the anodized component substrate (i.e., in-situ OCP data collection 208); collecting the electrochemical surface potential measurement data; and feeding or adding these tests, along with other industry-standard tests 204 and surface characterization 206 protocols, to the database 212. For example, only test specimens are measured during this method. In the example, OCP 214 is measured by performing in-situ OCP monitoring 216 during production and added back to database 218. During the analysis and optimization phase 220, the process is further optimized (i.e., process optimization 222), and troubleshooting 224 is also performed based on the information in database 212 and related information in database 212. In the analysis and optimization phase 220, the electrochemical surface potential measurement data is analyzed, and one or more performance indicators related to sealing quality and processing parameters are identified. The information obtained from the analysis of the electrochemical surface potential measurement data can be used to optimize the sealing process.

[0035] In an example of a method for in-situ monitoring and optimization of the sealing process, a potentiostat and a reference electrode can be used to measure the electrochemical surface potential. The measurement of the electrochemical surface potential can be performed on a test anodized substrate representing the surface of the anodized component. More specifically, measuring the electrochemical surface potential of the corresponding test anodized substrate includes measuring the open-circuit potential (OCP) of the corresponding test anodized substrate as the sealing process proceeds. Other surface characterizations 206 can be performed, which may include capturing and evaluating scanning electron microscope images and energy-dispersive X-ray spectroscopy (SEM / EDS) and glow discharge-photoemission spectroscopy (GDOES) on cross-sectional images, which will be described in further detail herein.

[0036] Additionally, during the sealing process, while sealing the surface of the anodized substrate, a test anodized substrate corresponding to the anodized substrate is transferred to the same sealing process. Measuring the electrochemical surface potential of the test anodized substrate, representing the surface of the anodized component, using in-situ open-circuit potentiometry, can be used to generate electrochemical surface potential data for input into a database and serve as the basis for collecting and storing electrochemical surface potential measurement data and other data collected during the sealing process for subsequent evaluation, optimization, and troubleshooting of the sealing process. In the example, measurements can be performed in a conversion coating tank using an open-circuit potentiostat and a reference electrode directly immersed in the sealing solution. The database and the information collected therefrom can be used to inform adjustments to one or more parameters of the sealing process. One or more parameters of the sealing process may include at least one of the following: sealing solution concentration, pH, temperature, deoxygenation time, anodizing voltage, sealing duration, number of rinses, rinse quality (i.e., the quality of deionized water or the treatment bath), or a combination thereof.

[0037] When surface characterization methods such as glow discharge-photoemission spectroscopy (GDOES) are combined with open-circuit potential methods, elemental concentrations across a sealing layer depth of approximately 1 μm to approximately 150 μm can be analyzed. Example alloys used in the anodizing, sealing, and monitoring processes may include aluminum or aluminum alloys. The primary substrate is aluminum. Aluminum and its alloys may also be applicable.

[0038] The system for monitoring sealing treatment as described herein may include a potentiostat, an electrochemical cell, and at least one reference electrode, wherein the at least one reference electrode is immersed in a sealant solution to measure the open-circuit potential (OCP) of the interface between the anodized alloy surface and the sealant solution. In the example, at least one reference electrode is immersed near the test panel (approximately 1 cm). The system may also include a computer-readable medium storing software configured to store or analyze data from the potentiostat and at least one reference electrode, wherein the analyzed data is used to optimize treatment parameters specific to the sealing treatment of the aluminum alloy substrate material. Where other testing methods or surface characterization methods are used in the system, data, images, or other information generated by these methods or protocols are also stored and / or analyzed by the computer-readable medium storing the software. The at least one reference electrode may include a standard calomel (SCE) type reference electrode.

[0039] Industry-standard testing can include neutral salt spray corrosion testing and wet and / or dry adhesion testing. Surface characterization methods can include SEM cross-sectional imaging, glow discharge-photoemission spectroscopy (GDOES), and the aforementioned in-situ OCP data collection. Open circuit potential (OCP) monitoring generates the distribution of potential over time, which can be combined with other well-known testing methods to establish a standard treatment database. This database can identify characteristics in the distribution that can be used as performance indicators and for root cause analysis (RCA) of sealing treatment problems or characteristics. Methods and systems including OCP monitoring can provide a means to optimize treatment parameters specific to any given aluminum substrate, inform and guide troubleshooting in production sealing treatments, and provide faster information and results turnaround, delivering information in less than one day compared to the current benchmark of over two weeks for neutral salt spray testing.

[0040] Open circuit potential (OCP) is assessed at the interface between the anodized aluminum and the trivalent chromium treatment (TCP) sealed solution and can be measured in situ as a function of time. The test panel can be fully immersed in the solution, and measurements are performed using a reference electrode and a potentiostat. The electrochemical interactions (including dissolution and film formation) in these measurements occur at the interface between the anodized surface and the TCP sealed solution. A standard calomel reference electrode (SCE) is used to measure the relationship between OCP and immersion time. In some examples, measurements can be performed using Ag / AgCl (silver / silver chloride), Hg / HgO (mercury / mercuric oxide), Cu / CuSO4 (copper / copper sulfate), a standard hydrogen electrode (SHE), or combinations thereof.

[0041] In the example, the corresponding 2-inch × 2-inch test panels are exposed to the TCP sealing solution through an O-ring-sealed opening in an electrochemical flat cell, which includes a standard calomel (SCE) reference electrode and the TCP sealing solution. These test panels undergo a standard chemical cell line treatment step before or during OCP measurements in the TCP-sealed electrochemical cell.

[0042] In the example, a database built using industry-standard testing, surface characterization, and open-circuit potential (OCP) data enables real-time optimization of processing parameters by correlating OCP values ​​with performance metrics such as film thickness, porosity, and chemical composition. This allows operators to adjust processing conditions based on changes detected during production.

[0043] An exemplary reference electrode is used directly within the chemical processing line for continuous monitoring and control of seal quality. By integrating this technology into existing production lines, real-time process optimization can be achieved without interrupting or slowing down production.

[0044] Furthermore, various examples of OCP analysis can be combined to provide a comprehensive understanding of sealing performance. For instance, combining slope changes with inflection points can indicate optimal processing conditions for a specific aluminum alloy substrate. Similarly, correlating peak values ​​in the potential-time distribution with surface characterization data (e.g., film thickness) allows operators to adjust processing parameters based on actual seal quality.

[0045] Figure 3 This is a schematic diagram of an exemplary open-circuit potential monitoring setup according to this disclosure. The open-circuit potential (OCP) can be measured at the interface between the anodized aluminum alloy and the TCP sealing solution, and can also be measured in situ as a function of time. The test panel is fully immersed in the solution, and the measurement is performed using a standard reference electrode equipped with a potentiostat. The open-circuit potential monitoring device 300 shown includes an aluminum alloy 302 with an anodized layer 304. The measurement method investigates the electrochemical interactions (e.g., dissolution and film formation) occurring at the interface 306 between the anodized layer 304 on the surface and the TCP sealing solution 308. Measurements are performed using a reference electrode 310 (e.g., a calomel electrode, also referred to as a standard calomel reference electrode (SCE) connected to a potentiostat 312) to measure the relationship between OCP and immersion time.

[0046] Measuring the electrochemical surface potential using a reference electrode and potentiostat within an electrochemical cell, as shown in the figure, can be a useful method for in-situ monitoring of anodic sealing processes to generate real-time data. This setup allows for precise control of processing conditions such as temperature (e.g., 20°C ± 1%, or 80°C in the case of a precision thermocouple), pH level (±0.01 units), and solution concentration (%w / v). For example, the test sample can be immersed in a TCP sealant containing 5% to approximately 45% by weight, or approximately 10% to approximately 30% by weight of trivalent chromium. Exemplary solutions used can have a pH in the range of 3 to 4 and operate at temperatures from approximately 35°C to approximately 45°C.

[0047] In one example, the electrochemical cell can be configured to simultaneously accommodate multiple samples for batch testing or sequential processing of different materials. A reference electrode ensures accurate potential measurements relative to a known standard (e.g., Ag / AgCl), while a potentiostat controls and records changes in surface potential over time with high precision (<1 mV). This setup allows for real-time monitoring of the electrochemical interaction between the anodized aluminum and the TCP-sealed solution, thereby optimizing processing parameters specific to any given substrate.

[0048] In another example, the temperature-controlled chamber can be integrated into or around the electrochemical cell to maintain precise thermal conditions during measurement. This can be achieved, for example, using a thermoelectric module or a precision heating / cooling system (±0.1°C). This capability allows testing in a variety of environmental scenarios that can affect seal formation and surface potential.

[0049] In another example, a microelectrode array can be combined with a potentiostat to measure localized electrochemical activity at specific points on the surface of a test sample. This allows for spatially resolved analysis of film growth rates, porosity distribution, or other properties affecting sealing performance. The distance between measurement points is typically between 0.1 mm and 100 mm.

[0050] As described in this article, data processing software can be used to analyze OCP distribution and extract additional information about seal quality, such as indicating changes in the slope of the dissolution reaction or representing the inflection point at the onset of film formation. This allows for real-time monitoring of processing control parameters, such as temperature, pH level, solution concentration, anodizing voltage, and seal duration. These parameters can be adjusted accordingly to optimize processing conditions.

[0051] In the examples, alternative electrode designs, such as Ag / AgCl, Cu / SO4, or Hg / HgO, can be used instead of the calomel reference electrode. This may require further validation or qualification testing to ensure compatibility with the specific application. The electrochemical cell can be constructed using materials compatible with TCP solutions and can withstand temperatures up to 80°C or higher as required without compromising measurement accuracy.

[0052] In another embodiment, multiple test specimens can be measured simultaneously in separate compartments within the array electrode design, or by rotating a single specimen through different processing conditions prior to measurement. This approach allows for simultaneous monitoring of various processing parameters while minimizing variability between samples and ensuring consistent results. Testing multiple specimens simultaneously using this method can capture the effect of processing conditions on the OCP distribution over time. This also allows for direct comparisons between different processing parameters or substrate materials, enabling optimization strategies tailored specifically to individual aluminum alloys.

[0053] In examples of optimizing TCP sealing treatments on aluminum or other alloys, multiple readings can be taken over a time period of at least 30 minutes to capture the initial film formation phase and subsequent surface potential changes. In other examples, OCP values ​​can be measured at regular intervals over specified time periods (typically ranging from 30 minutes to several hours). Commercial electrochemical analysis software packages, such as Gamry Frameworks or NOVA, or packages provided by Gamry Instruments and Metrohm, can be used to analyze data from these measurements.

[0054] In another example, the automated system can integrate a calomel reference electrode with other sensors to monitor temperature, pH, conductivity, and dissolved oxygen levels within the TCP solution in real time during processing. This integrated setup can continuously optimize processing parameters in response to changes detected by each sensor or OCP measurement data from multiple test samples. In this example, automation will be the result of continuous measurements by the electrodes and sensors, as well as software generating and / or providing information for tank maintenance / adjustment requirements based on feedback from a database. In yet another example, the electrochemical cell can be designed as part of a larger system for real-time monitoring on the production line using sensors and software that can detect deviations from optimal conditions during processing.

[0055] To ensure accurate and reliable data collection, various embodiments of this method involve the use of different types of reference electrodes, such as calomel (SCE), Ag / AgCl, Hg / HgO, or others. The choice of electrode depends on the specific application requirements, including compatibility with the solution composition, temperature range, and the required level of accuracy.

[0056] Figure 4 This is a graph illustrating the open-circuit potential (OCP) distribution according to this disclosure. Typically, the open-circuit potential (OCP) distribution provides data relating to the net potential of competing reactions. For example, a negative slope may indicate that dissolution is the dominant reaction in a given treatment. Alternatively, a positive slope may indicate that film formation is the dominant reaction in the treatment. Specific characteristics of each distribution can be observed, influenced by internal conditions such as solution concentration, pH, temperature, or external conditions such as any pre-sealing treatments such as deoxidation steps, anodizing, or rinsing conditions. Figure 4 The open-circuit potential (OCP) versus time graph illustrates the evolution of potential during trivalent chromium sealing treatments at different concentrations, with the shaded area defined by the vertical arrow indicating the optimal sealing time. It should be noted that for a given treatment and set of conditions, this window, as well as the slope and shape of the OCP versus SCE curve over time, may differ. Using this evolving database of data, the characteristics and OCP values ​​measured at specific times along the distribution can be used to assign performance grades and understand the quality of TCP seals, indicating what actions need to be taken in terms of treatment control.

[0057] Figure 5 This is a schematic diagram of a sputtering arrangement for an exemplary glow discharge-photoemission spectroscopy (GDOES) measurement according to this disclosure. Depth distribution measurement 500 shows a cross-section of a metallic alloy component 510 (e.g., an aluminum alloy), wherein an anodized layer 506 has an incorporated TCP sealing layer 508. Measurements are performed using sputtering 502 or a material removal step, followed by glow discharge-photoemission spectroscopy (GDOES) measurement 504. This measurement is performed several times across the entire depth of the anodized layer 506 to provide the composition of one or more elements (in this case, a metal) as the depth penetrates further. This method can further enhance data analysis capabilities because various examples of the methods in this disclosure involve combining OCP distribution characteristics with surface characterization methods such as SEM / EDS cross-sectional imaging or GDOES measurements at resolutions up to 150 μm (1 μm). This integrated approach provides a comprehensive understanding of the sealing formation process by correlating electrochemical interfacial behavior with physical properties such as film thickness, porosity, or chemical composition. Other examples may include cross-sectional SEM imaging and focused ion beam transmission electron microscopy (FIB-TEM).

[0058] In addition to optimizing processing parameters for specific aluminum alloys, this method can also be used in production environments for real-time monitoring and troubleshooting, providing additional performance details. By integrating OCP measurement settings into a larger system or channel monitoring station, operators can quickly identify deviations from optimal conditions or defects indicating seal quality problems, enabling rapid corrective action and minimizing downtime.

[0059] Analyzing the characteristics and values ​​of the OCP distribution is a useful aspect of this technique; these characteristics and values ​​indicate and can be correlated with desired performance levels, troubleshooting, or processing control actions. This involves plotting the potential versus time distribution under various processing conditions to identify specific characteristics that indicate seal quality and optimal operating parameters. For example, changes in slope can indicate the onset of film formation, while inflection points can represent useful stages in the sealing reaction. Peaks or plateaus within these curves can indicate a steady state achieved during processing optimization.

[0060] In one example, software packages such as CorrosionPro can be used to analyze OCP data by plotting the potential versus time distribution under different processing conditions and identifying specific features related to seal quality metrics such as film thickness, porosity, and the chemical composition of the forming layer. This enables real-time monitoring and control of processing parameters during actual manufacturing operations.

[0061] In another example, a combination of surface characterization methods, such as SEM / EDS cross-sectional imaging and GDOES, can be used in conjunction with OCP data analysis to understand the seal formation process. By analyzing characteristics such as the film thickness, porosity, and chemical composition of the formed layer, the operator can determine the optimal processing conditions for a specific aluminum alloy or substrate.

[0062] In the example, the weight percent of zirconium (Zr) or chromium (Cr) is used as a function of apparent depth, such as by glow discharge-optical emission spectroscopy (GD-OES) to compare with... Figure 5 The measurement setup depicted is similar to that described above. This measurement can be used to characterize the evolution of film formation under specific immersion times, processing conditions, or other parameters, such as their effect on the presence of various metals (e.g., Cr and Zr), as shown. This specific surface characterization method can be used to understand the seal-forming process, input into a database, and correlated with OCP and other collected data. While the generated data may indicate an increase or decrease in both Cr and Zr, this may not necessarily reflect the data obtained in each process, and other metals may be detected, depending on the processing or the material being evaluated or measured in other weight percentages or relative compositions. In the example, characterization methods may include SEM / EDS cross-sectional imaging, glow discharge optical emission spectroscopy, or a combination thereof, wherein glow discharge optical emission spectroscopy is capable of measuring depth distributions from approximately 1 μm to approximately 150 μm.

[0063] The system and method disclosed herein are provided for creating a database using industry-standard testing, surface characterization, and open-circuit potential data to enable OCP monitoring as an independent performance indicator. In-situ OCP testing can be performed in an electrochemical cell or in a device using a reference electrode directly in a chemically treated sealed tank.

[0064] With the replacement of chromium (VI) or hexavalent chromium coatings with chromium (III) or trivalent chromium, further industry-standard testing and evaluation of coating treatments are required. In particular, the evaluation and database establishment of relevant chemical treatments during sealing, along with analytical software with suitable interfaces coordinated with sealing treatments, provide methods and systems for tank optimization. Parameters such as immersion time and other treatment parameters for candidate or unknown materials can be studied and controlled to a greater extent. Sealing treatments used to improve the corrosion resistance and adhesion of metal substrates can also be improved and further quantified. In some examples, non-anodizing treatments using conversion coatings are also applicable.

[0065] This application involves the following provisions:

[0066] 1. A method for in-situ monitoring and optimizing sealing treatment, the method comprising the following steps:

[0067] The surface of the sealed anodized substrate;

[0068] The test anodized substrate corresponding to the anodized substrate is provided in the same sealing process as the anodized substrate;

[0069] Measure the electrochemical surface potential of a test anodized substrate that represents the surface of an anodized component;

[0070] Collect electrochemical surface potential measurement data;

[0071] Analyze the electrochemical surface potential measurement data; and

[0072] Identify one or more performance metrics related to sealing quality and processing parameters.

[0073] 2. The method for in-situ monitoring and optimization of sealing treatment according to Clause 1, the method further comprising the step of: optimizing the sealing treatment using information obtained from analyzing the electrochemical surface potential measurement data.

[0074] 3. The method for in-situ monitoring and optimization of sealing treatment as described in Clause 1, wherein a potentiostat and a reference electrode are used to measure the electrochemical surface potential.

[0075] 4. The method for in-situ monitoring and optimized sealing treatment as described in Clause 1, wherein the step of measuring the electrochemical surface potential of the corresponding test anodized substrate includes: measuring the open circuit potential (OCP) of the corresponding test anodized substrate.

[0076] 5. The method for in-situ monitoring and optimization of sealing treatment as described in Clause 1, the method further comprising the step of performing surface characterization on the corresponding test anodized substrate.

[0077] 6. The method for in-situ monitoring and optimization of sealing treatment as described in Clause 5, wherein the steps of performing the surface characterization include: SEM / EDS cross-sectional imaging and glow discharge-optical emission spectroscopy (GDOES).

[0078] 7. A method for monitoring sealing processes, the method comprising the following steps:

[0079] The surface of the sealed anodized substrate;

[0080] The test anodized substrate corresponding to the anodized substrate is transferred to the same sealing process as the anodized substrate;

[0081] Electrochemical surface potential data of a test anodized substrate, representing the surface of anodized components, were generated by in-situ measurement using the open-circuit potential method.

[0082] Analyze the electrochemical surface potential measurement data.

[0083] 8. The method according to Clause 7, further comprising the step of measuring the electrochemical surface potential of the test anodized substrate in a conversion coating bath.

[0084] 9. The method according to Clause 7, wherein the electrochemical surface potential is measured using a potentiostat combined with a reference electrode directly immersed in a sealed solution.

[0085] 10. The method according to Clause 7, further comprising the step of: adjusting one or more parameters of the sealing process.

[0086] 11. The method according to Clause 10, wherein the one or more parameters include at least one selected from the group consisting of: sealing solution concentration, pH, temperature, deoxygenation time, anodizing voltage, sealing duration, rinsing quality, and rinsing number.

[0087] 12. The method according to Clause 7, further comprising the step of: characterizing the surface of the test anodized substrate using a surface characterization method.

[0088] 13. The method according to Clause 12, wherein the surface characterization method comprises the step of combining glow discharge-photoemission spectroscopy (GDOES) with open-circuit potential analysis to analyze the elemental concentration distribution across a sealing layer depth of 1 μm to 150 μm.

[0089] 14. The method according to Clause 7, wherein the substrate comprises anodized aluminum or an aluminum alloy.

[0090] 15. A system for monitoring sealing processes, the system comprising:

[0091] Potentiostat;

[0092] Electrochemical cells; and

[0093] Reference electrode; and

[0094] The reference electrode is immersed in a sealant solution to measure the open-circuit potential (OCP) at the interface between the anodized alloy surface and the sealant solution.

[0095] 16. The system for monitoring sealing processes as described in Clause 15, the system further comprising:

[0096] Test panel, the test panel being made of the anodized alloy; and

[0097] The reference electrode is immersed in the vicinity of the test panel.

[0098] 17. The system for monitoring sealing processes as described in Clause 15, the system further comprising:

[0099] A computer-readable medium storing software configured to analyze data from the potentiostat and at least one reference electrode; and

[0100] The analyzed data was used to optimize the specific processing parameters for sealing aluminum alloy substrate materials.

[0101] 18. The system for monitoring sealing processes as described in Clause 15, wherein the reference electrode comprises a standard calomel SCE type reference electrode.

[0102] 19. The system for monitoring sealing treatment as described in Clause 15, wherein the anodized alloy comprises aluminum.

[0103] While this teaching has been shown with respect to one or more implementations, changes and / or modifications may be made to the illustrated examples without departing from the spirit and scope of the appended claims. For example, it is understood that although a process is described as a series of actions or events, this teaching is not limited to the order of such actions or events. Some actions may occur in a different order and / or simultaneously with other actions or events besides those described herein. Furthermore, not all processing stages require implementation of the method according to one or more aspects or embodiments of this teaching. It is understood that structural objects and / or processing levels may be added, or existing structural objects and / or processing levels may be removed or modified. Moreover, one or more actions depicted herein may be performed in one or more separate actions and / or stages. Furthermore, the use of the terms “comprising,” “including,” “having,” or variations thereof in the detailed description and claims is intended to be inclusive in a manner similar to the term “comprising.” The term “at least one of” is used to indicate that one or more of the listed items may be selected. Furthermore, in the discussion and claims herein, the term "on" with respect to two materials, one "on" the other, signifies at least some contact between the materials, while "on" signifies that the materials are close but may be in contact with one or more other intermediate materials, making contact possible but not required. As used herein, "on" and "above" do not imply any directionality. The term "conformal" describes a coating material in which the angle of the underlying material is maintained by the conformal material. The term "about" indicates that the listed values ​​may be slightly varied, as long as such variation does not result in a treatment or structure inconsistent with the illustrated embodiment. The terms "connected," "joined," "for connection," "connected," and "linked" refer to "direct connection" or "connection via one or more intermediate elements or components." Finally, the terms "exemplary" or "illustrative" indicate that the description is used as an example and not implying that it is ideal. Other embodiments of this teaching will likely be apparent to those skilled in the art upon consideration of the specification and practice disclosed herein. This specification and embodiments are intended to be considered exemplary only, and the true scope and spirit of this teaching are indicated by the appended claims.

Claims

1. A method for in-situ monitoring and optimizing sealing treatment, the method comprising the following steps: The surface of the sealed anodized substrate; The test anodized substrate corresponding to the anodized substrate is provided in the same sealing process as the anodized substrate; Measure the electrochemical surface potential of a test anodized substrate that represents the surface of an anodized component; Collect electrochemical surface potential measurement data; Analyze the electrochemical surface potential measurement data; as well as Identify one or more performance metrics related to sealing quality and processing parameters.

2. The method for in-situ monitoring and optimized sealing treatment according to claim 1, the method further comprising the following steps: The sealing process is optimized using information obtained from analyzing the electrochemical surface potential measurement data.

3. The method for in-situ monitoring and optimized sealing treatment according to claim 1, wherein, The electrochemical surface potential was measured using a potentiostat and a reference electrode.

4. The method for in-situ monitoring and optimized sealing treatment according to claim 1, wherein, The steps for measuring the electrochemical surface potential of the corresponding test anodized substrate include: measuring the open circuit potential (OCP) of the corresponding test anodized substrate.

5. The method for in-situ monitoring and optimized sealing treatment according to claim 1, the method further comprising the following steps: Surface characterization was performed on the corresponding test anodized substrate.

6. The method for in-situ monitoring and optimized sealing treatment according to claim 5, wherein, The steps for performing the surface characterization include: SEM / EDS cross-sectional imaging and glow discharge-photoemission spectroscopy (GDOES).

7. A method for monitoring sealing processes, the method comprising the following steps: The surface of the sealed anodized substrate; The test anodized substrate corresponding to the anodized substrate is transferred to the same sealing process as the anodized substrate; Electrochemical surface potential data of a test anodized substrate representing the surface of anodized components were generated by in-situ measurement using the open-circuit potential method. as well as Analyze the electrochemical surface potential measurement data.

8. The method according to claim 7, further comprising the following step: The electrochemical surface potential of the test anodized substrate was measured in a conversion coating tank.

9. The method according to claim 7, wherein, The electrochemical surface potential was measured using a potentiostat combined with a reference electrode directly immersed in a sealed solution.

10. A system for monitoring sealing processes, the system comprising: Potentiostat; Electrochemical cells; as well as Reference electrode; and The reference electrode is immersed in a sealant solution to measure the open-circuit potential (OCP) at the interface between the anodized alloy surface and the sealant solution.

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