Forging High-Tech Armour from Shock-Dispersing Fractal Cubes

Additively manufactured fractal structures with closely spaced vacuums disintegrate shock-waves five times better than solid cubes.

Tiny, 3D printed cubes of plastic, with complex fractal vacuums built into them, have proven to be effective at dispersing shock-waves, potentially leading to new types of lightweight armour and structural materials effective against explosions and impacts.

“The goal of the work is to manipulate the wave interactions resulting from a shock-wave,” said Dana Dattelbaum, a scientist at Los Alamos National Laboratory.

Shock-wave dispersing materials that take advantage of vacuums have been developed in the past, but they typically involved random distributions discovered through trial and error. Precisely controlling the location of holes in a material allows the researchers to design, model, and test structures that perform as designed, in a re-producible way.

The researchers tested their fractal structures by firing an impactor into them at approximately 670 miles per hour. The structured cubes dissipated the shocks five times better than solid cubes of the same material.

Although effective, it’s not clear that the fractal structure is the best shock-dissipating design. The researchers are investigating other void- or interface-based patterns in search of ideal structures to dissipate shocks. New optimization algorithms will guide their work to structures outside of those that consist of regular, repeating structures. Potential applications might include structural supports and protective layers for vehicles, helmets, or other human-wearable protection.

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