Researchers North Carolina State University have developed a fiber that combines rubber elasticity with metal strength, resulting in tight material that could be incorporated into soft robotics, packaging or next generation techniques.
"A good way of explaining the material is to think about rubber bands and metal wires," said Michael Dickey, the corresponding author of paper on paper and Professor Alcoa Chemical and Biomolecular Engineering in CC State.
"Rubber band can stretch very far, but it does not take much force to expand," said Dickey. "A metal wire requires a lot of power to stretch, but it can not be very stressful – it's broken before you can extend it far away. Our fibers have the best of & # 39; both worlds. "
The researchers created fibers that contain a metal core of a gauze that has been surrounded by elastic polymer leaves. When stressed, the fiber has the strength of the metal core. But when the metal breaks, the fiber fails – the polymer rod absorbs the stress between the breaks in the metal and transmits the stress back to the metal core. This response is similar to the way human tissue holds broken bones.
"Every time the metal core breaks it, it splits energy, allowing the fiber to continue to absorb energy as it extends," said Dickey. "Instead of blowing in two after extending, it can extend up to seven times its original length before failure, causing many additional breaks in the wire along the way.
"To think of it in another way, the fiber will not tighten and fall heavyweight, instead, by repeatedly releasing energy, the fiber will slowly reduce the pressure slowly and gradually."
In materials, hardness is able to absorb energy and deform material without breaking. You can think of it as the amount of force that material can absorb as it is being deformed for a distance. The new fiber is much tight than one of the metal wire or the polymer wool alone.
"There is a lot of interest in engineering materials to imitate the intensity of the skin – and we have developed a fiber that has surpassed the skin hard, yet it's elastic as a skin," said Dickey.
In addition, the kernel core is conductor – although it loses its productivity when the internal core breaks. The fibers can also be reused by melting the metal pools together.
"We used calculus for this test work of concept, but the fibers could be suitable to change their mechanical properties, or to maintain functionality at higher temperatures, by using different materials in the core and; The shell, "said Dickey.
"This is a concept of concept only, but it has a lot of potential. We are interested to see how these fibers could be used in soft or textile woven in textiles for different applications."
Materials provided by North Carolina State University. Note: Content may be edited for style and length.