NASA is taking their Electron Beam Freeform Fabrication (EBF3) technology to the next level, according to a report in The Daily Mail.
EBF3 is a type of 3D printing that uses a high-power electron beam to instantaneously melt metallic wire. The fluid metal is then positioned incrementally to build up arbitrary solid metal objects. This could prove quite handy for distant astronauts who are not easily able to run down to the store for spare parts; they could potentially just make them on orbit.
While NASA has had this tech for some years, they've recently begun testing prototype EBF3 printers in a temporary weightless environment provided by NASA's reduced gravity aircraft (also known as the "vomit comet"). The machine can be exposed to a weightless environment for as long as 25 seconds, making testing possible but tedious.
A full test would obviously involve locating the EBF3 printer on the Space Station, but it sounds like they have much work to do before they get to that stage. One can imagine the added safety measures that must be introduced before such a device would be permitted aboard the station.
But if they succeed in doing so, the Space Station could benefit from avoiding the need to stock many types of spare parts onboard, and instead simply keep a few coils of metal wire ready to be fused into whatever is necessary.
Via The Daily Mail