ISS Could Get its Own Electron-Beam Fabrication 3-D Printer

Electron Beam Freeform Fabrication: An electron beam melts
a metal feedstock, layering the raw molten material into
a predetermined part or object. EBF3 could head to the ISS in
the near future. NASA

Every good futuristic sci-fi narrative has its version: Star
Trek had the replicator that produced Picard's piping hot
Earl Grey from what appeared to be thin air, and Forbidden
Planet had Robbie the Robot, who generated entire luncheons
from the chemical lab in his nether regions. But NASA
scientists have come many real-world steps closer to creating
something from nothing, via a process called electron beam
freeform fabrication, and a version of the technology will
soon be going to the International Space Station for testing.

Electron Beam Freeform Fabrication, or EBF3, takes place in
a vacuum chamber in which an electron beam is focused on
a source of metal that is constantly fed into the beam. The
electron beam melts the metal atop a rotating surface,
applying the molten feedstock in layers as directed by
a detailed 3-D drawing of the object being produced. The
process continues until the object is done, rendered
completely from drawing to usable metal part.

Though not quite as versatile as the Enterprise's replicator,
EBF3 technology has myriad commercial applications aside from
its scientific implications. All one needs to fabricate
a part for, say, a commercial airliner or a medical device is
a 3-D rendering of the part and a feedstock that is
compatible with the electron beam (that is, something the
beam can liquify). The drawing must be highly in-depth,
however, breaking the object into layers that the EBF3
machine can understand and accommodate.

But once that drawing is made once, the airline manufacturer
or the device maker can conjure that part on demand and
on-site, saving money and time. Furthermore, because layering
together a part from molten metal requires less waste than
machining a part from a solid block, EBF3 is exponentially
more environmentally friendly than conventional fabrication
methods. Some aircraft builders machine 300-pound parts from
6,000-pound blocks of titanium; EBF3 could produce the same
part from just 350 pounds, saving 5,650 pounds of titanium
that would normally have to be recycled.

EFB3 can also feed two different feedstocks into the machine
at once, opening up more opportunities for innovation. For
instance, part makers could embed a strand of fiberoptic
cable inside a part, allowing the placement of sensors in
places where it was previously impossible.

But let's not forget the sci-fi implications as well. Future
crews manning a lunar base could use EBF3 to create parts and
tools as needed (rather than ordering them from Earth
a quarter million miles away). As for feedstocks, they could
scrap their landing crafts, but they might also be able to
mine them from the moon's soil, bringing sustainable space
dwelling that much closer to reality.

The EBF3 equipment tested on the ground is quite bulky, but
a scaled down version was created and subsequently flown to
near-weightlessness on NASA's Reduced Gravity Aircraft. The
next step should be a trip to the ISS, though the EBF3 is
still waiting for a spot on a mission manifest. While it may
not produce the crew's afternoon tea, it could someday supply
a critical part at a crucial moment. That's more than we can
say for the replicator.