The field of powder technology is crucial in various industries, including pharmaceuticals, ceramics, and metallurgy, where the manipulation and processing of fine powders are essential. A significant challenge in this field is the tendency of fine powders to agglomerate, forming larger clusters that can impede the efficiency and quality of processes such as aerosol-based film deposition. These agglomerates can lead to defects in films, reduce deposition efficiency, and limit the achievable film thickness.
The need for effective deagglomeration methods is critical to enhance the performance and quality of products in these industries, driving the demand for innovative solutions that can efficiently break down these clusters without compromising the integrity of the individual particles. Current approaches to deagglomeration often involve heat treatments or segregation of powders, both of which have significant drawbacks. Heat treatments can lead to the formation of strongly bonded aggregates, which are difficult to break apart and can negatively affect the quality of the final product.
Segregation, on the other hand, is inefficient and costly, as it involves discarding a significant portion of the powder that remains agglomerated. This not only increases waste but also raises production costs. Furthermore, existing methods may not be suitable for all types of powders, particularly ceramics, where larger aggregates can severely impact deposition processes. The limitations of these approaches highlight the need for more efficient and versatile deagglomeration technologies.
The technology described is a method for deagglomerating powders by subjecting them to strong shear forces. This method involves suspending powder agglomerates in a fluid, typically an inert gas, and passing them through narrow gaps between rotating aluminum discs and a static body to create an aerosol. The device uses a screw feeder to meter the powder and fluid into the deagglomerator, where the rotational velocity of the discs, ranging from 1,000 to 30,000 rpm, determines the shear force applied to the particles.
The design includes features like a sapphire window sealed by O-rings to isolate the aerosol from the atmosphere and a magnetic coupler pair to transmit torque to the shearing disc rotor. This setup allows for precise control over the deagglomeration process, making it suitable for fine powders used in aerosol-based film deposition processes.
What differentiates this technology is its ability to deagglomerate fine powders in a dry state, a capability not commonly found in existing devices. Current methods for handling agglomerates involve either heat treatments that create strongly bonded aggregates or segregation of non-agglomerated fractions, both of which are inefficient and costly. This technology offers a more efficient solution by enabling the use of the entire powder batch, reducing waste and improving the quality of films produced in processes like cold spray. Additionally, the method’s adaptability to various fluid types and its ability to handle fine powders as small as 50 nm make it versatile for multiple industrial applications, including paint manufacturing and other processes requiring fine powders.