FROM
msnbc article, updated 4:47 p.m. CT, Wed., Nov . 4, 2009; by Jeremy Hsu of space.com
MY SUMMARY
NASA has developed a technology called Electron Beam Freeform Fabrication (EFB3), which could enable on-site manufacturing allowing creation of spare parts, like a bolt, screw, even shovels. The method
uses an electron beam to melt metals and build objects layer by layer, then
adjust the speed that you feed the wires, and that would
change the shape of the object or even it's very chemistry if two or more material types are available. All it requires is three crucial things: power for its electron beam, a vacuum environment, and a source of metals (presumably wires are the ideal shape fo the metals). Somebody
feeds metal wires continually
into the tip of
an electron beam. The
beam melts the wires and applies them carefully on top of a rotating plate to build an object up slowly, layer by layer.
Broken parts need not remain useless - they
could simple be recycled, namely by placing the part back into the feedstock, or can we mine new material. The idea is to bring along the material needed to make the part or tool, but, but not the tool itself.
NASA researchers managed to build a prototype roughly the size of a suitcase, to be tested later in orbit.
EBF3 already promises to
cut manufacturing costs for the aerospace industry, and could pioneer development of new materials. They foresee
cost savings of up to $1,000 per pound of manufactured parts, compared to the
usual forging and machining
methods that
require a 6,000-pound block of titanium to produce a 300-pound part. Furthermore, one could
embed fiber optic cables inside a solid piece of metal, either for use in communication or for monitoring stresses within the manufactured part.
Major aerospace manufacturers have
already begun running thousands of strength tests with the EBF3 device to see whether it can produce certified parts for engines and airframes, researchers said. Furthermore, it can even allow onsite manufacturing of small parts in orbit - manufacturing tools with materials already available on the Moon, Mars, and other places. Although the weight of the raw materials will equal the weight of the completed parts, it will make storage of the material quicker and cheaper, reducing mission costs.