Superstrong Fibers Could Be Hairy Situation
This is scientific American sixty seconds science. I'm Suzanne Bartlett. All all mammals have hair commonly called called for when it's on your cat or Koala and the thickness of individual hairs varies from species to species. For example elephant. Hairs are more than four. We're times thicker than a strand from an adult human namo nave the animal AIDS larger. The hair has to be faker. University of California San Diego material scientists when Yang. She's interested in how biological structures like hair hold up under stress. That interest comes from a desire fire to design better synthetic materials. Yang's team tested the tensile strength of hair from eight different mammal species including humans. They subjected subjected those hairs to increasing levels of tension until the fibers broke the researchers assume that thick hair from giraffes elephants in boars for example people would be more robust but they were wrong. Ain't texting late. Refine the thinner hair actually is stronger. In fact adult human hair was some one of the strongest in the study and children's hair. The thinnest of all was even more durable. Yang's team took a closer look at the hair with a scanning electron microscope. Hi Chris Cope. All hair is made of the Protein Carrington. The microscope views revealed specific patterns of breakage in the Carribean fibers which are composed of a protective detective outer cuticle and inner cortex that provides strength the microscope. Images showed that the CORTEX thicker hair tends to snap when broken leaving clean even break but the inner cortex of thinner hair breaks off less evenly. Yang compares the process to what happens when a powerful gust of wind blows lows a tree down in those cases that trump tends to shear at an angle. And that kind of break is a sign of strength. It actually takes more attention to cause shearing than a a clean break. The researchers found that the cutoff point between these two types of breakage was about two hundred micrometres about two and a half times thicker than human hair. The study is in the Journal matter. Young is now attempting to mimic the complex structure of hair in the lab with three D. printing once the technology is perfected down to the Nanno scale. These artificial fibres could be used to create a variety of strong materials for use in construction or even rescue operations operations such as nearly indestructible ropes. Until then we'll just have to be content with the knowledge that fewer than a thousand human hairs can support entire person's weight think of all the strength that's left on the hair salon floor. Thanks for listening for scientific American sixty seconds science. I'm Suzanne Bard.