Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Plastic Ceramic

14.12.2005


Scientists from Obninsk in the Kaluga reg. (Russia) have developed a ceramic with unique properties, with heat conductivity and thermoplasticity several times higher than normal ceramics. This means that items made of it, from coffee mugs to fuel pellets for atomic power stations, will serve longer and more reliably than standard ceramics.



During a competition of innovative developments under the 5th International Innovation and Investment Salon that was held 15-18 February 2005, researchers demonstrated some amazing samples.

“A distinguishing feature of our ceramic is its structure,” explains project manager and chief scientist of the Leipunsky Physics-Energy Institute Irina Kurina. “And, as a consequence, the properties are indeed unique. Heat conductivity that exceeds reference data, enhanced plasticity and thermal stability: we have succeeded in obtaining a ceramic in which all these properties are combined.”


Generally speaking, plasticity and high thermal conductivity for massive ceramic products are properties that are almost unrealistic. For example, rubber: if you strike it, individual molecules will as if to move, changing their form a little and the thing remains intact. Or, if metal is heated, surplus heat quickly spreads from the surface to the center and an ingot, say, remains completely intact, only warm. But ceramic is a brittle material: if struck it will break; if heated rapidly it will crack or even fall to pieces.

It is precisely for this reason that a special concept of stability in thermal cycling regimes is introduced for products made from it. Put simply, it is defined in advance how many times a ceramic item can be heated and cooled until it begins to crack by itself, under load or under an impact.

“Generally speaking, there are three types of component in the structure of the ceramic made under our technology: large grains of oxide material (from 50 to 100µm), fine grains (from 1 to 10µm) and a little emptiness. In other words there are pores, located in a special way, predominantly around the boundaries of the grains,” continues Kurina. “Such pores create ideal conditions for plastic deformation. And fine grains additionally soften a mechanical or thermal impact. In the mass of fine grains, the large grains become as if stuck, like cobblestones in sand. The crystalline lattice of such a ceramic is very mobile; it has many defects. In the unusual structure of such a ceramic electron tunneling is possible. This is where the high heat conductivity comes from.”

The principal basis of the technology is both simple and universal in nature. At first it is necessary obtain a powder, whereby the grains have to be of a varied, pre-set size. And there have to be an awful lot of defects in the obtained powder particles! All begins from sedimentation (precipitation): solutions of initial substances are taken, necessary reagents are added, and out comes the sediment – those very particles of the required size.

Then these oxide particles (of aluminum, magnesium and zirconium, thorium or uranium in the case of fuel components) are annealed, pressed and sintered. It is understood that the authors are not disclosing the technological parameters of these parameters and the subject of the know-how. However, all this work is extra confirmation of the fact that chemistry is not only strictly a matter of calculation, although the parameters of the new materials can be optimized with computer modeling, which is what the authors are doing. It is also an art form, the talent and intuition of the scientists who enable the achievement of what would seem to be the impossible; such as making a heat-conducting oxide ceramic, and of any kind.

Andrew Vakhliaev | alfa
Further information:
http://tech-db.istc.ru/istc/sc.nsf/events/plastic-ceramic

More articles from Materials Sciences:

nachricht New design improves performance of flexible wearable electronics
23.06.2017 | North Carolina State University

nachricht Plant inspiration could lead to flexible electronics
22.06.2017 | American Chemical Society

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>