A. DeBiccari, Pratt & Whitney, East Hartford, CT; D. Clark, University of Birmingham, Birmingham, United Kingdom; K. A. Green, Rolls-Royce Corporation, Indianapolis, IN; M. Kinsella, AFRL/MLLMP, Wright-Patterson AFB, OH; S. Tewari, GE Aircragt Engines, Cincinnati, OH

Summary:

Static superalloy components, such as diffuser and turbine cases, are among the most expensive parts found in gas turbine engines. Drivers for these high costs include inefficient material usage (high buy-to-fly ratios) and machining costs for forgings and material, mold costs, and re-work for castings. The use of additive manufacturing has the potential to attack multiple cost drivers simultaneously, resulting in significant cost and lead-time reductions.

The Metals Affordability Initiative (MAI) has funded a program to investigate additive manufacturing for superalloy cases. In an initial study, electron beam wire deposition, laser powder deposition, and a gas-tungsten arc wire feed methods were evaluated for both technical and economic feasibility. Generic deposits typical of those found on gas turbine engine cases were made and evaluated both destructively and non-destructive to show that microstructural and deposition quality standards could be met. Additionally, cost models of the various deposition processes were developed and used to show that aggressive cost-reduction targets could be achieved through additive manufacturing. This talk will describe the details and results of this feasibility study, and discuss additional tasks to be completed as part of the MAI program.