Submissions of air and space craft designs for GE’s MakerBot to produce have been pouring in on GE’s Facebook page over the last few weeks. Check out the video below to see the winning spaceships:
Printing non-toy planes is closer than you might think. This week’s Txchnologist, the online magazine sponsored by GE, investigates how 3D printing is being incorporated in the aircraft industry:
A lab in GE’s Global Research Headquarters in Niskayuna, New York is leading these forays into the world of additive manufacturing, the catchall phrase that includes 3D printing and metal printing technologies. (GE is the sponsor of this magazine). Lab manager Prabhjot Singh says that perfecting metal fabrication will move the technology from quirky Maker Faires to factory floors. “This is the application that’s going to get additive manufacturing on the map,” Singh said.
Lab manager Prabjhot Singh with a powder-bed additive manufacturing machine. Photo Chris New
The machines for the metal fabrication process, known as laser powder bed additive manufacturing, have been used in academic labs for about two decades. But when the additive manufacturing group got their hands on one, they started tinkering and pushing the process into new areas. The same pattern has held in other areas of additive manufacturing – engineers are using advanced manufacturing tools to create objects, rather than creating objects and figuring out how to manufacture them. It’s as if Henry Ford had the River Rouge Complex first, then discovered he could build vehicles there.
The machines can create complex parts that would be difficult or impossible to create using conventional manufacturing processes. On a recent day at the lab, Singh displayed a demonstration model of one such shape, a cylinder within a cylinder. The printer can create the complex shapes because it reduces three-dimensional objects to a two-dimensional plane by printing one layer at a time. (Airbus parent EADS has been experimenting with similar processes).
Tests of printed metal aircraft parts. Courtesy GE
Not surprisingly, the powder bed process starts with a heap of metallic powder. A laser then melts sections of the powder in a precise design. After each layer is complete, the machine covers the object in a fresh coating of powder, which is then lasered. The metal can be a nickel alloy or a special type of steel. The resulting part is lighter than its conventionally produced counterpart and just as strong. Shaving just one kilogram off of an aircraft’s weight can mean fuel savings of $3,000 per year, according to some estimates.
The challenge for the lab is to keep the material’s porosity — soft spots in the metal — to a very low level, in this case a fraction of 1 percent. The technology also still is limited to printing small objects on the order of about 1 foot by one 1 by 1 foot. Singh said GE’s aviation division is at an advanced stage of testing the parts for inclusion in future products. The parts are being placed in test engines, where heat and other stresses are more demanding, and will eventually become part of aircraft engines.
