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 Scientists predict a new superhard material with unique properties
17.06.2018 | Moscow Institute of Physics and Technology

nachricht A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive
15.06.2018 | University of California - San Diego

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive

15.06.2018 | Materials Sciences

100 % Organic Farming in Bhutan – a Realistic Target?

15.06.2018 | Ecology, The Environment and Conservation

Perovskite-silicon solar cell research collaboration hits 25.2% efficiency

15.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>