[MUSIC PLAYING] SPEAKER: MIT researchers
have developed a new technique for rapid 3D
printing with liquid metal. Using their process,
they can produce furniture-sized aluminum
parts in a matter of minutes. Their technique
involves depositing molten aluminum along
a predefined path into a bed of tiny glass beads. The aluminum then
quickly hardens into a 3D structure
durable enough to withstand post-print
machining, such as milling and boring, to construct
functional furniture like tables and chairs. There are existing methods
for printing with metals which are common in
construction and architecture. But these printed
structures can be susceptible to
cracking and warping because some portions must be
remelted during the printing process. This new method keeps
the material molten throughout the entire
process, therefore avoiding some of the structural
issues caused by remelting. The aluminum is held at a
high temperature in a graphite crucible and is gravity-fed
through a ceramic nozzle into the print bed
along a preset path. They found the larger amount
of aluminum they can melt, the faster the printer can go. The team chose aluminum
because it is commonly used in construction and is an
infinitely recyclable material. Having a machine that
allows people to melt down recycled aluminum and print
parts, the researchers say, would be a game-changer
in metal manufacturing. Their technique does sacrifice
resolution for speed and scale. However, in some applications
in architecture, construction, and industrial design,
components of larger structures often don't require
extremely fine details. It could also be
utilized effectively for rapid prototyping with
recycled or scrap metal. Moving forward, the
researchers want to keep iterating on
the machine so they can enable consistent heating in
the nozzle to prevent material from sticking and to achieve
better control over the flow of molten material.
