Economics of 3D printing ceramic cores for gas turbine investment castings

Abstract

Recent supply chain issues affecting the airfoil casting industry have renewed interest in industrial-scale 3D printing of ceramic cores. Ceramic cores are conventionally manufactured through injection molding. However, injection molding of low-volume production runs can be challenging because of the long lead times and high costs associated with mold tooling. 3D printing can mitigate up-front tooling costs, but there are other trade-offs, e.g., higher material costs of 3D printing feedstocks. Here, we develop a techno-economic model that accounts for costs (materials, tooling, equipment), core size, experience curve effects, and other important variables to determine threshold production volumes for which 3D printing is less expensive than conventional processing techniques. Using market data from 2019, our analysis shows that 3D printing a single dedicated core design with typical dimensions for aeroengine applications is less expensive than injection molding below ∼1,800 units. By simultaneously printing multiple core designs, this threshold increases to 120,000 units, or approximately 2 % of the 2019 aeroengine market demand. This threshold value decreases with increasing core size, indicating 3D printing is less favorable for large castings used in industrial gas turbines. These results are compared against the demand for ceramic cores in engine development, engine sustainment, and new engine manufacturing.