Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Superlubricant effect explained using new friction force sensor

11.04.2003


Graphite had already been extensively studied. German physicist Martin Dienwiebel was therefore extremely surprised when he discovered a completely new effect in this well-known lubricant. During research into the frictional properties of the material, he discovered that the frictional force almost completely disappeared at a certain moment.

Dienwiebel only intended to test the new friction force microscope he had developed. The Tribolever is a raster microscope which can measure frictional forces of just a few picoNewtons in three spatial dimensions. With his new instrument Dienwiebel first of all studied the frictional properties of graphite.

Graphite consists of carbon atoms arranged in layers one above another. The carbon atoms in a graphite layer form a sort of undulating landscape, which is similar to an egg box. The different layers can slide over each other. However, resistance can occur during the sliding process if the hills of one layer fit exactly into the valleys of another layer. Yet if the two layers are rotated with respect to each other, there are always points within the contact surface where the hills touch each other. As a result of this the two layers cannot collapse into each other and the resistance is overcome. The researcher has termed this phenomenon superlubrication.



A spray can with graphite lubricant is full of small graphite flakes. Upon spraying, these flakes land in a totally random manner. Consequently all of the flakes are automatically rotated with respect to each other and can therefore glide over each other with the minimum of resistance. The superlubricant effect discovered by Dienwiebell could be the basis of graphite’s outstanding lubricating qualities.

Graphite is not the only material for which the physicist wants to determine the frictional properties. As the properties of most materials change upon being exposed to air (for example, due to corrosion), Dienwiebel has also designed a friction force microscope that can work in an ultrahigh vacuum. The combination of this method with other microscopic techniques such as raster electron microscopy should make it possible to carry out a complete characterisation of friction in the future.

Nalinie Moerlie | alfa
Further information:
http://www.nwo.nl

More articles from Physics and Astronomy:

nachricht Innovative LED High Power Light Source for UV
22.06.2017 | Omicron - Laserage Laserprodukte GmbH

nachricht Spin liquids − back to the roots
22.06.2017 | Universität Augsburg

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

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)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

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

Mathematical confirmation: Rewiring financial networks reduces systemic risk

22.06.2017 | Business and Finance

Spin liquids − back to the roots

22.06.2017 | Physics and Astronomy

Hubble captures massive dead disk galaxy that challenges theories of galaxy evolution

22.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>