In the October issue of Circuit Cellar, Collin Ladd and Dr. Michael Dickey will be writing an essay about a North Carolina State University group’s fascinating research into 3-D printing with liquid metals.
“Most 3-D printers currently pattern plastics, but printing metal objects is of particular interest because of metal’s physical strength and electrical conductivity,” Ladd and Dickey say in their essay.
The process involves a needle that dispenses an alloy of gallium and indium, which in turn enables the 3-D printing of metals at room temperature. These flexible, bendable structures hold their shape and hold promise for uses including wires, antennas, flexible displays, wearable sensors, and skin substitutes on prosthetics. They can even “heal” themselves, the researchers say.
“Using our approach, we can direct print freestanding wire bonds or circuit traces to directly connect components—without etching or solder—at room temperature. Encasing these structures in polymer enables these interconnects to be stretched tenfold without losing electrical conductivity. Liquid metal wires also have been shown to be self-healing, even after being completely severed. Our group has demonstrated several applications of the liquid metal in soft, stretchable components including deformable antennas, soft-memory devices, ultra-stretchable wires, and soft optical components,” according to the essay.
But like many advances in technology, there was a certain amount of simple good luck in the pace of their research. That luck involved the introduction of Dr. Dickey to undergraduate student Ladd, whom Dickey credits for playing a key role:
“Collin worked in my lab as an undergraduate for almost three years and recently graduated. During that time, he was an undergraduate with unusual talent. He built the 3-D printer in our lab from spare parts. He got the machine to work and did a lot of the measurements that led to the (published research) paper. He also created the incredible video that is posted on YouTube.
“I first met Collin when he was a student in my class. He was one of those rare students who was a genuinely curious learner, but with no real concerns about grades. I found that refreshing. He came to my office one day and I found out that he was doing experiments in his apartment! I told him he should really be working in the lab, and the rest is history.”
So even though you won’t be seeing the research team’s full essay until Circuit Cellar‘s October issue is available online and in print, we thought we would share Ladd’s “incredible video” of the team’s work.
We’d also like to add that no insect was harmed in the making of this video (the bug receiving a pair of liquid metal antennae in the final footage had previously met its demise at the “hands” of a spider).