content: Aircraft engines are already being 3d printed:  https://www.ge.com/reports/treat-avgeeks-inside-look-ges-3d-printed-aircraft-engine/  Also 3d printing fuel nozzles for the upcoming GE 9X jet engine:  https://qz.com/667477/ge-fires-up-worlds-largest-commercial-jet-engine-using-3d-printed-metal-parts/  slated for use on the Boeing 777X among others. An Italian company 3d printing the turbo fan blades for the same 9x engine:  https://www.ge.com/reports/future-manufacturing-take-look-inside-factory-3d-printing-jet-engine-parts/  The 3D-printed blades spin inside the engine at 2,500 times per minute and face searing heat and titanic forces. “These are big blades,” says Giorgio Abrate, general manager for engineering at Avio Aero. “We ran a lot of experiments to get the job right.” The 3D printing factory, which looks like a blue and gray jewel box of steel and glass from the outside, holds 20 black, wardrobe-sized 3D printers, made by Arcam. A single machine can simultaneously print six turbine blades directly from a computer file by using a powerful 3-kilowatt electron beam. The beam “grows” the blades, which are 40 centimeters long, by welding together thin layers of titanium aluminide powder, one after another.  3D printing is only getting started. Add to the mix these new alloys like TiAl and the potential applications just keep expanding.  Did ya see the car that was almost entirely 3D printed?