When it comes to fighting for a mate, few in the animal kingdom can pull through unscathed like dueling deer. Their remarkably tough antlers take a huge beating when butting heads, so much so that material scientists have been probing the secrets of their toughness for years. Now researchers say they have cracked the code, attributing the robustness to a staggered arrangement of nanoscale fibers, something that could lead to similarly "unbreakable" materials down the track.
Deer antlers have a pretty special set of characteristics in that they are not only tough enough to absorb serious impacts, they are also stiff enough to push their foes backward so that they can gain the upper hand in a bout. These enviable attributes have led scientists to investigate the secrets of deer antlers, with previous research suggesting moisture levels have a part to play. But now a team from the Queen Mary University of London (QMUL) claims to have found the underlying reason.
Through advanced computer modeling and x-ray techniques, the researchers observed the antler structure on a nanoscale level. They say this revealed the mechanisms responsible for their durability, an intermittently arranged set of fibers that seem to have evolved to take a hit, partnered with a breakable, shock-absorbing substance made up of non-collagenous proteins and minerals in between.
"Non-collageneous proteins contains weak bonds that can easily break and re-form, called sacrificial bonds," co-author Dr Ettore Barbier explains to New Atlas. "This interfibrillar matrix gets damaged because of breakage of sacrificial bonds and de-bonding between minerals and non-collagenous proteins. The staggering, meanwhile, is responsible for smoothing the stress concentrations and enabling effective shear transfer between fibers."
The team says this new understanding of deer antlers could also shed new light on the structural modeling of bone. But the immediate focus is to use the knowledge to work towards a new generation of damage-resistant materials that can be produced through 3D-printing.
"Our next step is to create a 3D printed model with fibers arranged in staggered configuration and linked by an elastic interface," says Barbieri. "The aim is to prove that additive manufacturing – where a prototype can be created a layer at a time – can be used to create damage-resistant composite materials."
The research was published in the journal ACS Biomaterials.
Source: Queen Mary University of London