Even the most expensive bike locks can be compromised in just a few minutes, and mostly serve as deterrents so your ride is a less appealing target. But researchers from Durham University in the UK and the Fraunhofer Institute have created what they’re claiming is the first man-made material that is non-cuttable, by actively destroying tools that are trying to slice through it.
You could always try wrapping your bike in a diamond shield to make it impossible for a thief to steal it before you returned from an errand. But even diamonds, one of the hardest materials on earth, can still be sliced and shaped using jeweler’s tools (also made of diamonds) with enough time and patience. There’s also the issue of what a diamond bike lock would cost you.
Proteus, the name given to the new material by its creators, takes an entirely different approach. Where diamonds are incredibly strong thanks to their highly organized and dense atomic structure, Proteus is actually 85% less dense than metal, but its unique structure, made from a mix of aluminum metallic foam and embedded ceramic spheres, turns tools against themselves, dulling cutting surfaces and becoming harder as the material is turned to dust.
It sounds like a material that was reverse-engineered from a crashed alien spacecraft, and it seems to fly in the face of traditional approaches used to create ultra strong and cut-resistant materials. As revealed in images and video of Proteus under attack, the external layers of the material can be easily sliced and penetrated, but once a saw blade or drill bit hits the ceramic spheres embedded just below, vibrations are created that quickly dull the sharp edges of a tool, reducing their effectiveness.
At the same time, small particles of ceramic dust build up as the spheres are cut, filling the aluminum foam structure to make it denser and harder as the speed of the cutting tool increases. It’s similar to the way tiny particles in a sand bag will stiffen when compressed to absorb the force of, and stop, a speeding bullet
Cross-sections of the Proteus material, revealing the foam-like aluminum lattice structure and the embedded ceramic spheres arranged in lines.Illustration: Nature.com
YouTube is filled with videos of people using high-pressure water jet machines to cut through all types of objects with ease. They seemingly outperform even the most capable saws, but the researchers point out that Proteus is just as effective at resisting damage from a water jet as the shape of those ceramic spheres tends to spread out the fine stream of water, reducing its speed and power.
The team of researchers didn’t necessarily have bike locks in mind as the reason for creating Proteus, but the material could be just as effective when it comes to creating lightweight armors that could make any vehicle as strong as a tank, without the massive size and horrible gas mileage. It could also be used to develop protective equipment for people who use dangerous tools like angle grinders and table saws.