Made from nickel phosphorus, the microlattice emulates human cell structure, reaching a density and surface area similar to lung tissue. So light it can be balanced on the top of a dandelion seed head, the material weighs in at approximately 100 times lighter than styrofoam.
“The point of achieving the record for lightest metal was to show the flexibility of the manufacturing process,” said Bill Carter, Director of the Sensors and Materials Laboratory at HRL. “With the same process, we can produce a strong and useful material that can be made with the density of aluminum all the way down to well below the density of air (excluding the air inside). Achieving a density at any point between those requires only a small change in the creation process. It can be done quickly, relatively inexpensively, and made to order.”
To build the microlattice, a customizable polymer template is constructed through a “self-forming photopolymer waveguide process” and then electroplated with a layer of nickel-phosphorus with a thinness of approximately 80 nanometers, about 1,000 times thinner than the width of a human hair. The polymer is then removed using a chemical process.
The resulting product is the ultra-thin material and is capable of absorbing large amounts of energy throughout its structure.
The manufacturing process is both rapid and scalable, leading HRL to anticipate the microlattice could viably be used in applications including insulation, heat exchange devices, catalytic converters, airplane wings, military helmets, vehicle blast protection, and even to develop an artificial lung.