Advanced Filtration to Improve Single Crystal Casting Yield

Mikro Systems Inc. (Mikro) has developed an advanced manufacturing platform called Tomo Lithographic Molding (TOMO). The platform has been successfully applied to produce highly engineered products, including turbine airfoils for power generation and aviation flight. Specifically, TOMO is currently being used to produce ceramic cores for investment casting of advanced turbine blades and vanes. This has enabled the production of internal cooling geometries that are beyond the current state-of-the-art, thus providing potential fuel savings for next generation turbines. Mikro now proposes to extend the use of TOMO within the investment casting process through the development of engineered ceramic filters for metal casting. Current state casting filters are not sophisticated from a design perspective and no specific filters have been engineered for single crystal (SX) casting. Our proposal will focus on developing ceramic filters that will optimize filtration performance while enabling directional flow of molten alloy during the SX casting process. These performance advantages will be enabled through the geometric design of the filter. Another anticipated benefit is the ability to design part-specific filtration schemes for advanced airfoil castings. This performance optimization could significantly improve casting yields, lowering the cost and thereby removing a primary obstacle to more wide spread use of SX casting for industrial gas turbines and other critical investment cast products. The market potential for this technology is significant because the ceramic filters can be used for land based and aviation turbine applications as well as any other investment cast parts using SX techniques.