The U.S. Dept. of Defense issued a $14.09-million contract to Pratt & Whitney Military Engines to develop a process for “directed-energy deposition” (DED) repair of integrally bladed rotors. The Pentagon is seeking “an innovated approach to establish a repair process that will result in a fully organic and automated integrally bladed rotor repair capability.”
Directed-energy deposition is a metal additive manufacturing process involving a laser that melts powdered metal that is supplied to a target area, to fuse the metal to an existing structure. Typically, the laser beam travels through the powder deposition head, in a process guided along a tool path using a digital model.
Integrally bladed rotors (IBR) are a common design feature of gas turbine engines in military use. IBRs replace rotors with inserted blades, which reduces the part count and improves assembly and maintainability.
Pratt & Whitney – which manufactures an extensive range of military aircraft engines, including the F135, the F119, the F100 series of turbofan engines, among others – has adopted metal AM technologies for rapid prototyping and R&D cost reduction, and it has been reported to be interested in the potential of DED for producing larger parts and adding features to existing parts.
The development will be carried out at Pratt & Whitney’s operation in East Hartford, Conn., and is expected to be completed in about 18 months.
Neither the DoD nor Pratt & Whitney commented on the project.
