Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



TECH SPACE
Sea urchin spurs new ideas for lightweight materials
by Staff Writers
Copenhagen, Denmark (SPX) Nov 18, 2015


The heart urchin lives its entire life dug into the sea bottom. Its fragile looking calcium shell needs to withstand the combined pressure of half a meter of sand and a couple of meters water. Dirk Muter of University of copenhagen, Department of Chemistry, discovered, that this makes it one of the toughest creatures known. Image courtesy Jes Andersen/University of Copenhagen. For a larger version of this image please go here.

Materials researchers love sea creatures. Mother-of-pearl provokes ideas for smooth surfaces, clams inspire gluey substances, shark's skin is used to develop materials that reduce drag in water, and so on. Researchers at the University of Copenhagen's Department of Chemistry have now found a model for strong, lightweight materials by diving below the sea surface to investigate a sea urchin cousin known as the heart urchin.

Dirk Muter is an assistant professor in the Department of Chemistry's NanoGeoScience research group. He headed the project, which is now now published in Acta Biomaterialia under the title, "Microstructure and micromechanics of the heart urchin test from X-ray tomography".

Heart urchins (Echinocardium cordatum), also known as sea potatoes, measure up to 5 cm in diameter, are heart shaped and burrow in sand. They extend a channel to feed upon organic particles from the waters above their burrow.

Like "regular" sea urchins, these "irregular" heart urchins are soft creatures that use their calcium carbonate exoskeletons to protect their otherwise edible bodies from predation. And as it turns out, their shells are unexpectedly robust.

The idea to study heart urchin shells dawned upon a vacationing Muter while he was walking down a Croatian beach. The paper-thin urchin shells were washed up onto the beach, and Muter observed that they had astonishingly few blemishes despite being so thin.

To understand the sturdy calcium carbonate shells, Muter and his colleagues used a relatively new technology called x-ray microtomography. The technique was used to create three-dimensional images of the material contents, without having to break the shells up into pieces.

The x-ray images are so fine that it is possible to distinguish structures of less than one-thousandth of a millimetre. This ultra fine resolution proved decisive in coming to understand the shell's strength.

Anyone who has ever broken a piece of chalk knows that calcium carbonate is fragile. And, heart urchin shells consist of more air than chalk. In fact, as one gets up close to the shell material, it begins to resemble soapsuds.

The material consists of an incredible number of microscopic cavities held together by slender calcium carbonate (chalk) struts. There are between 50,000 and 150,000 struts per cubic millimetre, and in some areas, the material is composed of up to 70% air.

Calcium carbonate can be many things, from unyielding marble to the soft and somewhat brittle chalk that we use to write with. While heart urchin shells and writing chalk share a similar porosity, the urchin shells are up to six times stronger than chalk.

Muter's studies demonstrate that heart urchin shells have a structure that nears a theoretical ideal for foam structure strength - a must for a creature that has evolved to withstand life under 10 metres of water and an additional 30 centimetres of sand.

Muter explains that to their great surprise, heart urchin shell strength varied between shell regions due to greater or lesser concentrations of struts within specific regions, not because of thinner or thicker struts.

"We found an example of a surprisingly simple construction principle. This is an easy way to build materials. It allows for great variation in structure and strength. And, it is very near optimal from a mechanical perspective," states Assistant Professor Dirk Muter.

Muter and his NanoGeoScience colleagues expect that their new insights will serve to improve shock- absorbent materials among other outcomes.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
Faculty of Science - University of Copenhagen
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
TECH SPACE
Researchers find way to make metals stronger without sacrificing ductility
Raleigh NC (SPX) Nov 18, 2015
Researchers at North Carolina State University and the Chinese Academy of Sciences have developed a technique to make titanium stronger without sacrificing any of the metal's ductility - a combination that no one has achieved before. The researchers believe the technique could also be used for other metals, and the advance has potential applications for creating more energy-efficient vehicles. ... read more


TECH SPACE
Gaia's sensors scan a lunar transit

SwRI scientists explain why moon rocks contain fewer volatiles than Earth's

All-female Russian crew starts Moon mission test

Russian moon mission would need 4 Angara-A5V launches

TECH SPACE
Curiosity Mars Rover Heads Toward Active Dunes

Upgrade Helps NASA Study Mineral Veins on Mars

Dust devils detected by seismometer could guide Mars mission

Amnesia Event Slows Down Opportunity Robotic Arm Work

TECH SPACE
Orion ingenuity improves manufacturing while reducing mass

Orion's European module ready for testing

General Dynamics demos SGSS Command and Control Infrastructure for NASA

Orion Service Module Stacking Assembly Secured For Flight

TECH SPACE
China to launch Dark Matter Satellite in mid-December

China to better integrate satellite applications with Internet

China's satellite expo opens

New rocket readies for liftoff in 2016

TECH SPACE
Cygnus Launch Poised to Bolster Station Science, Supplies

Progress cargo spacecraft to be launched Dec 21

Space station power short circuits, system repairs needed

Cygnus Starts Final Round of Processing for Station Cargo Delivery

TECH SPACE
Recycled power plant equipment bolsters ULA in its energy efficiency

Purchase of building at Ellington a key step in Houston Spaceport development plans

More launches ahead for UH's Hawaii Space Flight Laboratory

LISA Pathfinder topped off for Vega launch that will test Relativity

TECH SPACE
Rocket Scientists to Launch Planet-Finding Telescope

5400mph winds discovered hurtling around planet outside solar system

New exoplanet in our neighborhood

Asteroid ripped apart to form star's glowing ring system

TECH SPACE
Hydrogel superglue is 90 percent water

Simple errors limit scientific scrutiny

Researchers discover a new form of crystalline matter

Sea urchin spurs new ideas for lightweight materials




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement