NASA Debuts 3D-Printed Space Chain Mail

When it comes to applied material science, it's hard to beat NASA. Their solid-state wizards have been working on multiple ambitious projects, including silicon dioxide wafers and about a dozen kinds of ceramic composites. Now some folks at the JPL have debuted a new kind of engineered metallic fabric that they hope will see diverse applications in space -- and on other worlds.

The new metal fabric is a flexible hybrid of chain mail and plate armor, in the horticultural sense of a hybrid: the offshoot of two different parents, having certain distinct and hopefully desirable characteristics from both. NASA officials said in a statement(Opens in a new window) that this fabric and its kin have four essential functions: reflectivity, passive heat management, fold-ability, and tensile strength. Chain mail has the useful properties of light weight and flexibility, because it's made of a three-dimensional mesh. Its structure provides great tensile properties that let it collapse in on itself and stretch right back out without becoming work-hardened. But it's less effective at stopping certain kinds of impacts than plate armor, which also has better reflective properties.

So, in a reductionist sense, this new metal fabric is like chain mail, except with stuff attached to it. One side has little square metal plates on all the rings, to provide an almost unbroken surface of metal armor. An impactor that struck a sheet of this stuff would see the sheet flex and extend itself to catch the impactor. That would dissipate force across much of the fabric. But the fabric's properties as armor aren't the end of its utility. Those metal plates could be textured to use as next-gen treads on a rover like Curiosity, which relies instead on solid aluminum cleats. And the flip side of the fabric is no slouch: its geometry gives it specific thermal properties, like the shape of a heat sink.

The fabric is produced by additive manufacturing. Raul Polit Casillas, the systems engineer who designed the fabric, comes from a background of both systems engineering and fashion design. Unlike ring mail, there's no mail weaver at a desk with pliers and a bucket of split rings, weaving this stuff together and then welding the plates to one side of the fabric. Using CAD and 3D printing, the designers were able to construct this fabric without welds or other mechanical junctures.

Apart from his work in direct R&D, Polit Casillas also co-leads a rapid prototyping lab at the JPL called the Atelier. His spatial thinking has opened up new possibilities for mechanical engineering. "I can program new functions into the material I’m printing," said Polit Casillas. "That also reduces the amount of time spent on integration and testing. You can print, test and destroy material as many times as you want."

Because the material can be folded in on itself, it could be used for large antennas, solar sails, and other devices that have to be deployed in the field. Its electromagnetic properties also make it useful for missions to Europa and other places with extreme EM environments. And because it's done with additive manufacturing, the fabrics could plausibly be constructed in space -- or even on the surface of another planet, using metals refined there.

"We call it '4-D printing' because we can print both the geometry and the function of these materials," said Polit Casillas. "If 20th Century manufacturing was driven by mass production, then this is the mass production of functions."