Ultrasonic Spraying of Ti-Ir-Ta Coated Anodes for Al Foil Formation

Ultrasonic Spraying of Ti-Ir-Ta Coated Anodes for Al Foil Formation – Cheersonic

In the manufacturing process of modern aluminum electrolytic capacitors, the chemical treatment of aluminum foil is a key step in determining product performance. The chemical treatment aims to form a dense and uniform oxide film on the surface of aluminum foil through electrochemical methods, thereby endowing the aluminum foil with good insulation properties and dielectric properties. This process cannot be separated from high-performance anode materials, and titanium based iridium tantalum coated anodes have become the core components in aluminum foil production lines due to their excellent electrochemical performance and corrosion resistance. In recent years, the introduction of ultrasonic spraying technology has opened up a new technological path for the preparation of high-performance titanium based iridium tantalum coatings.

Material characteristics of titanium based iridium tantalum coating

The titanium based iridium tantalum coating belongs to the mixed metal oxide electrode system. Among them, iridium oxide, as the main active component, has excellent electrocatalytic activity and conductivity, which can effectively reduce oxygen evolution overpotential and improve current efficiency; Tantalum oxide, as a stable component, can significantly enhance the chemical inertness and corrosion resistance of coatings. The synergistic effect of iridium and tantalum enables the coating to exhibit excellent stability in strongly acidic and high current density electrolyte solutions. The titanium substrate provides excellent mechanical support and conductive substrate, and after appropriate pretreatment, it can form a strong bonding interface with the active coating.

Compared with traditional platinum electrodes or pure metal electrodes, titanium based iridium tantalum coated anodes not only significantly reduce the amount of precious metals used and save manufacturing costs, but also have a longer service life and more stable working performance. During the process of aluminum foil formation, the anode needs to withstand continuous oxygen evolution reactions and chemical corrosion from the electrolyte. Iridium tantalum coating can effectively resist this harsh environment, avoiding substrate passivation or dissolution.

The principle and advantages of ultrasonic spraying technology

The preparation method of the coating directly determines its microstructure and macroscopic properties. Ultrasonic spraying technology, as an emerging coating preparation process, is gradually replacing traditional brushing, thermal decomposition, or plasma spraying methods. The core of this technology is to use ultrasonic transducers to generate high-frequency vibrations, atomize the precursor solution into uniform droplets at the micrometer or even nanometer scale. These droplets are deposited on the heated titanium substrate surface under the guidance of a carrier gas, and then undergo thermal decomposition to form an oxide coating.

Compared with conventional pneumatic spraying, ultrasonic spraying has significant advantages. Firstly, the droplet size distribution is extremely uniform, avoiding the common phenomenon of “large particle splashing” in atmospheric pressure spraying, making the coating surface smooth and dense. Secondly, ultrasonic spraying can accurately control the flow rate and deposition amount of the coating liquid, making it easy to achieve controllable preparation of multi-layer and gradient structures. In addition, as the atomization process does not rely on high-speed airflow, the utilization rate of the coating solution can reach over 90%, significantly reducing the waste of precious metal precursors.

For titanium based iridium tantalum coatings, ultrasonic spraying technology can effectively improve the micro uniformity of the coating. The traditional brushing method is prone to defects such as uneven thickness and local cracks, while the small droplets formed by ultrasonic spraying spread evenly on the surface of the substrate. After multiple spraying and thermal decomposition, a dense oxide film without through cracks can be obtained. This structure reduces the channels for electrolyte to penetrate into the titanium substrate and suppresses the growth of interface passivation film; On the other hand, it also reduces the internal stress of the coating and extends the service life of the electrode.

Application effect in aluminum foil formation

The titanium based iridium tantalum coated anode prepared by ultrasonic spraying showed excellent comprehensive performance after being applied to the aluminum foil production line. Experimental research and industrial applications have shown that this type of anode has high oxygen evolution catalytic activity, stable formation voltage, uniform current distribution, and helps to form an oxide film with consistent thickness and low defect density on the surface of aluminum foil. Meanwhile, due to the dense coating structure and strong corrosion resistance, the weight loss rate of the anode during long-term operation is extremely low, avoiding tank contamination and product quality fluctuations caused by coating peeling or substrate corrosion.

Compared with conventional anodes, the working life of titanium based iridium tantalum anodes prepared by ultrasonic spraying can be extended by 30% to 50% under the same working conditions. This means that the frequency of electrode replacement during production line shutdown is significantly reduced, effectively improving production efficiency. In addition, due to the high utilization rate of coating solution, the consumption of precious metals per unit area of anode is reduced, which lowers production costs.

Conclusion

Ultrasonic spraying technology provides a high-quality, high-efficiency, and low waste process solution for the preparation of titanium based iridium tantalum coated anodes for aluminum foil formation. This method can accurately control the microstructure of the coating, fully utilize the synergistic effect of iridium and tantalum, and significantly improve the electrocatalytic activity and corrosion resistance life of the anode. With the continuous improvement of aluminum foil quality requirements for aluminum electrolytic capacitors, titanium based iridium tantalum coated anodes prepared by ultrasonic spraying will play an increasingly important role in the field of chemical treatment, promoting the development of the industry towards higher performance and lower cost.

About Cheersonic

Cheersonic is the leading developer and manufacturer of ultrasonic coating systems for applying precise, thin film coatings to protect, strengthen or smooth surfaces on parts and components for the microelectronics/electronics, alternative energy, medical and industrial markets, including specialized glass applications in construction and automotive.

Our coating solutions are environmentally-friendly, efficient and highly reliable, and enable dramatic reductions in overspray, savings in raw material, water and energy usage and provide improved process repeatability, transfer efficiency, high uniformity and reduced emissions.