(Almost) Unbreakable: Future gadgets with carbon springs

Posted by Wolfgang Gruener

Clemson (SC) – Researchers from Clemson University have discovered a way to make surfaces much more durable and protect them from damage in the case of severe impacts: The path to virtually unbreakable surfaces may lead across shock absorbing carbon springs. First tests delivered evidence that such springs could withstand and fully recover from enormous forces.

Imagine gadgets whose plastic surfaces would not break anymore when you drop them. You would not have to worry about your that expensive cellphone falling out of your pocket and you would feel much more comfortable about somebody accidentally swiping your electronic toy off a table.

A research team led by physics professor Apparao Rao of Clemson University claims to have made a discovery that may make that vision a reality one day. Rao and colleagues from the University of California at San Diego found that layers of tiny springs called coiled carbon nanotubes, each a thousand times smaller than a human hair, can act as extremely resilient shock absorbers. And they came up with a way to create these coiled nanotubes on a large scale.   

 

“The problem we have faced in the past is producing enough of these coiled carbon nanotubes at a reasonable cost to make a difference,” said Rao. “Because our current method produces coiled nanotubes quickly in high yield, it can be readily scaled up to industrial levels. After formation, the coiled nanotubes can be peeled off in one piece and placed on other surfaces to form instant cushioning coatings.”

Rao compared the way the nanotubes work to an egg toss: “If you move your hand backward as you catch the egg and increase the time of contact over which the impact occurs, the impact will be less forceful and the egg will not break. It is the same phenomenon experienced in catching a baseball.” In an experiment Rao and his team tested more conventional straight carbon nanotubes against coil-shaped nanotubes. When a stainless steel ball was dropped onto a single nanotube layer, the coiled nanotubes completely recovered from the impact, while the straight ones did not.

While the miniaturization of electronic devices forces scientists to come up with smaller and smaller structures, it seems that out that these devices are becoming much more fragile. Layers of these coiled nanotubes could be applied to virtually any surface the researchers said – not just gadgets, but also in soldiers’ body armor, car bumpers and even as cushioning elements in shoe soles.

“Our studies with carbon nanotubes have been ongoing for quite some time,” said Rao. “Each step along the way has led to the next breakthrough, and each time we’ve learned more about how they grow and what their applications could be. We believe that carbon nanotubes have tremendous potential for the lives of each one of us.”

The fact that Rao and his team believe that they can scale the production of these nanotubes to “industrial levels“ leads us to believe that this may actually be a technology we could see in commercial products within our lifetime. Rao was not available to talk about actual production and commercial product planning.