According to a new study Limpets teeth might be the
strongest natural material of the world.It is found by the Researchers from the
University of Portsmouth that limpets --
small aquatic snail-like creatures with conical shells, possess teeth with a
very strong biological structure.
With the use of atomic force microscopy they examined the
small scale mechanical behavior of teeth. Atomic force microscopy is a method
used to pull apart materials all the way down to the level of the atom.
The study as led by Professor Asa Barber from the
University's School of Engineering. He said: "Nature is a wonderful source
of inspiration for structures that have excellent mechanical properties. All
the things we observe around us, such as trees, the shells of sea creatures and
the limpet teeth studied in this work, have evolved to be effective at what
they do.
"Until now we thought that spider silk was the
strongest biological material because of its super-strength and potential
applications in everything from bullet-proof vests to computer electronics but
now we have discovered that limpet teeth exhibit a strength that is potentially
higher."
His research concluded that the teeth contains a hard
mineral goethite, which is formed in limpet as it grows.
He said: "Limpets need high strength teeth to rasp over
rock surfaces and remove algae for feeding when the tide is in. We discovered
that the fibres of goethite are just the right size to make up a resilient
composite structure.
"This discovery means that the fibrous structures found
in limpet teeth could be mimicked and used in high-performance engineering
applications such as Formula 1 racing cars, the hulls of boats and aircraft
structures.
"Engineers are always interested in making these structures
stronger to improve their performance or lighter so they use less
material."
The research also discovered that strength of limpet is
independent of it's size.
"Generally a big structure has lots of flaws and can
break more easily than a smaller structure, which has fewer flaws and is
stronger. The problem is that most structures have to be fairly big so they're
weaker than we would like. Limpet teeth break this rule as their strength is
the same no matter what the size."
The technique to break a sample 100 times thinner than human
hair is know till now, as the size of the research objet was saamThe material
Professor Barber tested was almost 100 times thinner than the diameter of a
human hair so the techniques used to break such a sample have only just been
developed.
He said: "The testing methods were important as we
needed to break the limpet tooth. The whole tooth is slightly less than a
millimetre long but is curved, so the strength is dependent on both the shape
of the tooth and the material. We wanted to understand the material strength
only so we had to cut out a smaller volume of material out of the curved tooth
structure."
Finding out about effective designs in nature and then
making structures based on these designs is known as 'bioinspiration'.
Professor Barber said: "Biology is a great source of
inspiration when designing new structures but with so many biological
structures to consider, it can take time to discover which may be useful."
The research was published today in the Royal Society
journal Interface
No comments:
Post a Comment