Additive manufacturing is one of the modern marvels of the engineering world and it could become even more useful thanks to laser technology. A 3D printer built at Harvard University's Wyss Insitute and Harvard SEAS can create metallic objects in midair. The printer operates through what is called 'direct ink writing' that releases metallic inks, which is instantly frozen in place by a laser. The nanoparticle inks are squirted out of a nozzle in the printer's manufacturing and the laser solidifies it into predetermined structures.
"This sophisticated use of laser technology to enhance 3D printing capabilities not only inspires new kinds of products, it moves the frontier of solid free-form fabrication into an exciting new realm, demonstrating once again that previously accepted design limitations can be overcome by innovation," Wyss Insitute Director Donald Ingber, told Engadget.
According to the researchers' video, the wires that are printed through the solidifying of the nanoparticle ink are thinner than the width of a hair and are complex metallic structures the minute it makes contact with the laser. The researchers think this breakthrough in additive manufacturing could create new opportunities in electronic devices, sensors and more.
However, it wasn't all smooth sailing in crafting such a 3D printer:
Mark Skylar-Scott, one of the head researchers on the project said: "If the laser gets too close to the nozzle during printing, heat is conducted upstream, which clogs the nozzle with solidified ink. To address, this we devised a heat transfer model to account for temperature distribution along a given silver-wire pattern, allowing us to modulate the printing speed and distance between the nozzle and laser to elegantly control the laser annealing process 'on the fly'".
The researchers published their findings in the Proceedings of the National Academy of Sciences of the United States of America under the title Laser-assisted direct ink writing of planar and 3D metal architectures.