The Spray Cast Process and its Applications in Gas Turbine Engines

The need for advanced material processing to reduce manufacturing cost and cycle times has never been as great as at this time in our nation’s history. Howmet Corporation has licensed and modified the Osprey, or spray forming, process to produce high quality nickel base superalloys for gas turbine engine applications. The modified process, known as the “Spraycast-X™” process, combined vacuum induction melting with high purity argon gas atomization to produce billet and ring shape products. Process parameters were established to produce fine grain size (ASTM 6-8) billet up to 10” (254 mm) in diameter and ring shape preforms up to 33” (838 mm) in diameter. Mechanical properties of HIP’ed Spraycast-X plus isoforged U720 and Spraycast-X and HIP’ed MERL 76 (no Hf) were comparable to their wrought counterparts. Mechanical property data for ring rolled IN718, René 41, and Waspaloy were all above specification limits.