Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Material tested that could guarantee body protheses for more than 150 years

23.02.2010
Current body protheses do not last more than 10-15 years. After this time, the operation has to be repeated in order to change prothesis. It is usually problematic as, in general, it is elderly people that use the procedure.

Researcher Nere Garmendia, based in the Basque city of Donostia-San Sebastián, has just published her PhD, a thesis which may well mean the first step to solving this problem. According to Ms Garmendia, using a ceramic material called zirconia (Zr02), carbon nanotubes and nanoparticles of zirconia, a prothesis that will last more than 150 years can be produced.

The PhD thesis is titled Development of a new nanocompound material made of zirconia with coated carbon nanotubes, for orthopaedic applications. Ms Garmendia wished to show that the ageing and cracking of protheses could be avoided. To begin with, carbon nanotubes were added to the zirconia matrix – a technique that greatly strengthens its resistance. With this composite material as a base research was initiated.

The researcher reinforced the connection between the zirconia matrix and the nanotubes, with the intention of improving the transfer/distribution of loads. The nanotubes were coated with nanoparticles of zirconia and, in order for this to be effected, the nanoparticles were heated beyond their boiling point (hydrothermal synhtesis). This coating functioned as a bridge between the zirconia matrix and the nanotubes.

Ms Garmendia explained in her thesis that working at a nanometric scale is precisely the key to achieving long-lasting protheses. In a prior experiment with micrometric zirconia it was concluded that this material would end up considerably aged after 12 years. Nevertheless, as has been pointed out, apart from the zirconia matrix, adding carbon nanotubes and the nanoparticles of zirconia coating them, the material will not age -even after 150 years.
The maximum possible density

With the nanotubes coated, Ms Garmendia investigated the capacity for the displacement and dispersion of the composite obtained from the previous process, and also looked for its suitable point of density. Based on this and aided by plaster, she achieved the first compact pieces.

Subsequently, Ms Garmendia specified the number of coated nanotubes each piece had to have in order to achieve the optimum density at the end of the process. According to the researcher, adding zirconia nanoparticles to the nanotubes facilitates the dispersion of the material and reduces its viscosity, apart from helping to increase its density for the next and last stage: the synterisation stage. Synterisation is a process, used particularly in ceramics, in order to transform the material from powder to a compact solid. Not just any quantity is useful to achieve this maximum possible density and, thus, before synterisation, it has to be decided how many nanotubes are to be introduced and, of course, synterisation has to be subsequently carried out correctly.

As Ms Garmendia calculated, if the intention is to obtain the maximum possible density (98%), in order to start the composition, 1% of its volume must be of coated nanotubes. Finally, the material has to be synterised in argon for one hour at 1,300 degrees; not more nor less.
About the author

Ms Nere Garmendia Arcelus (Donostia, 1980) is an industrial engineer, having graduated in 2003 from TECNUN-University of Navarra. She undertook her PhD thesis under the direction of Isabel Obieta Vilallonga and Ana García Romero, from the Department of Mining Engineering and Metallurgy and Materials Sciences of the Higher Technical School of Engineering in Bilbao.

She is currently working at Inasmet-Tecnalia where she carried out her PhD. She also worked with other bodies for the research: INSA-Lyon in France (six months), the Institute of Ceramics and Glass-CSIC in Madrid (six weeks), the Donostia International Physics Center (on various simulations), the Universitat de Barcelona (microscopy) and the CINN-CSIC in Oviedo (on the development of the material).

Amaia Portugal | EurekAlert!
Further information:
http://www.elhuyar.com

More articles from Materials Sciences:

nachricht The stacked colour sensor
16.11.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

nachricht Counterfeits and product piracy can be prevented by security features, such as printed 3-D microstructures
16.11.2017 | Karlsruher Institut für Technologie (KIT)

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>