Mid-air Printing Machine

STATES CHRONICLE – A new study on laser-assisted 3D printing machines with metal inks was published yesterday in Proceedings of the National Academy of Sciences.

Authors Mark A. Skylar-Scott, Suman Gunasekaran, and Jennifer A. Lewis at the Wyss Institute for Biologically Inspired Engineering and the John A. Paulson School of Engineering and Applied Sciences (SEAS) wrote a study they think might lead to advances in electronics and biotechnology.

The increased demand for “malleable” technology – wearables, sensors, antennas –   has led scientists to create a printing machine able to print in the air.

This laser-assisted printing device uses metal inks to create in one move, without auxiliary support, microscopic 3D architectures.

Lead author Jennifer Lewis says she is genuinely excited by the team’s development “which allows one to 3-D print and anneal flexible metal electrodes and complex architectures ‘on-the-fly.”

The ink is composed of silver nanoparticles that are sent through a printing duct. The annealing is done by a programmed laser that applies a sufficient amount of energy to solidify the ink.

The laser duct moves in a 3D plane combined with a rotary stage that allows curvature or freeform. Microscopic shapes, forms, motives can be printed in mid-air in a matter of seconds.

The printed materials present excellent electrical conductivity which makes this printing machine superior to other conventional 3D printing devices because the silver wires can be printed directly on cheap plastics.

Traditional 3D printing machines basically build objects layer by layer, making the next panel rely on the previous one to support the rest. Before this development, mid-air printed objects needed temporary support that would later be removed. No additional help here, though.

For the team, the most challenging part was to adapt the printing nozzle to a perfect separation distance from the laser. To prevent clogging the distribution duct or nozzle, the researchers devised a “heat transfer model” that allowed them to modulate printing distance and speed.

Through this model that accounts for temperature distribution on a silver-wire structure, the researchers can control the annealing in space.

This laser-assisted printing machine prints “on the fly” and can move in all directions. It opens up the doors to all kind of applications in the electronic and biotechnological field. It will revolutionize the 3D printing technology in general, improve electronics manufacturing, and do wonders for biomedical devices.

Image Source: Tech Crunch