As reported by GE, the method builds the blades from a titanium powder fused with a beam of electrons accelerated by a 3-kilowatt electron gun.
The gun is reportedly 10 times more powerful than laser beams currently used for printing metal parts, making it possible to build blades from layers of powder that are more than four times thicker than those used by laser-powered 3D printers. As a result, one machine can produce eight stage 7 blades for the low pressure turbine that goes inside the GEnx jet engine in just 72 hours. “This is very competitive with casting, which is how we used to make them,” says Mauro Varetti, advanced manufacturing engineer at Avio.
Blades made from the material can reduce the weight of the entire low pressure turbine by 20%.
Avoiding casting
The printer builds parts directly from a 3D computer drawing by melting layers of fine powder with an electron beam. The technology allows workers to preheat the powder and better control the part’s properties. Engineers can also change the shape of the blades and print different blades on the same machine in a quick succession, which would be laborious and expensive with casting.
Later this year, GE will start testing blades printed for the GEnx engine at its test facility in Peebles, Ohio. The parts will also go inside the GE9X, a new jet engine GE is developing for Boeing’s next-generation long-haul plane, the 777X. GE has also started building a new factory for making 3D-printed jet engine fuel nozzles in Alabama.
