Watch 3D Printing with Liquid Metal at Room Temperature (Video)

The process of 3D printing is gaining a lot of ground. It holds the potential to print artificial organs, tiny circuits and even food for astronauts. Now, scientists have developed 3D printing technology that can create free-standing structures made out of liquid metal at room temperature.

Liquid doesn't usually lend itself to forming structures. When you try to meld it into a shape, it will often coalesce into a larger droplet or will break apart entirely. In this case, though, researchers were able to create structures out of liquid, overcoming the destabilizing influence of surface tension.

The structures are pretty astounding when you see them at first. They look like beads of metal, welded together to form strands that can be molded into different sizes and shapes. Despite being liquid, though, these structures actually retain their shapes.

"It's difficult to create structures out of liquids, because liquids want to bead up," said Michael Dickey, one of the researchers, in a news release. "But we've found that a liquid metal alloy of gallium and indium reacts to the oxygen in the air at room temperature to form a 'skin' that allows the liquid metal structures to retain their shapes."

There are actually several different techniques to create the liquid metal structures, and the researchers are working on developing even more. The structures themselves can be used to connect electronic components in three dimensions, reaching either up or down depending on the situation.

One of the methods that the researchers developed involves stacking droplets of liquid metal on top of each other, much like a stack of oranges at a supermarket. These droplets adhere to one another, but retain their shape rather than merging into a single, larger droplet. Another technique involves injecting liquid metal into a polymer template so that the metal takes on a specific shape. The template is then dissolved, leaving behind only the liquid metal.

Currently, the scientists are examining exactly how to further develop these techniques. In addition, they're looking at how to use them in various electronics applications and in conjunction with established 3D printing technologies.

The findings are published in the journal Advanced Materials.

Want to see the printing in action? You can see the researchers "print" out the tiny droplets into a complex structure in the video below, courtesy of YouTube.