Navigation Links
Models present new view of nanoscale friction
Date:2/25/2009

MADISON To understand friction on a very small scale, a team of University of Wisconsin-Madison engineers had to think big.

Friction is a force that affects any application where moving parts come into contact; the more surface contact there is, the stronger the force. At the nanoscale mere billionths of a meter friction can wreak havoc on tiny devices made from only a small number of atoms or molecules. With their high surface-to-volume ratio, nanomaterials are especially susceptible to the forces of friction.

But researchers have trouble describing friction at such small scales because existing theories are not consistent with how nanomaterials actually behave. Through computer simulations, the group demonstrated that friction at the atomic level behaves similarly to friction generated between large objects. Five hundred years after Leonardo da Vinci discovered the basic friction laws for large objects, the UW-Madison team has shown that similar laws apply at the nanoscale.

The team, which was led by Izabela Szlufarska, an assistant professor of materials science and engineering, and included materials science and engineering graduate student Yifei Mo and mechanical engineering assistant professor Kevin Turner, published its findings in the Feb. 26 issue of the journal Nature.

Current nanoscale friction theories are based on the idea that nanoscale surfaces are smooth, but, in reality, the surfaces resemble a mountain range, where each peak corresponds to an atom or a molecule.

The UW-Madison team performed computer simulations that looked at nanoscale materials as a collection of atoms, monitoring their positions and interactions throughout the entire sliding process. "For the first time, we modeled friction at length scales very similar to experiments, while maintaining atomic resolution and realistic interactions between atoms," say Szlufarska.

The team discovered simple laws of nanoscale friction. They found that friction is proportional to the number of atoms that interact between two nanoscale surfaces. The researchers' simulations showed that, at the nanoscale, materials in contact behave more like large rough objects rubbing against each other, rather than as two perfectly smooth surfaces, as was previously imagined. "When you look at it closely, the surface is made of atoms, so the contact is actually rough," says Szlufarska.

The team's simulation data correlates very well with recorded experimental data something that previous models have failed to accomplish. Szlufarska hopes to use the simulations as a tool to understand what mechanisms contribute to friction on both the nano- and macroscale.

"Nobody is able to predict friction or design materials with desired friction properties we measure a lot of friction coefficients for different materials, but it's not really clear how to relate them to the properties of the material," she explains. "The origin of friction is really an open and growing research field."


'/>"/>

Contact: Izabela Szlufarska
izabela@engr.wisc.edu
University of Wisconsin-Madison
Source:Eurekalert

Related biology technology :

1. Mathematical models reveal how organisms transcend the sum of their genes
2. Sigma-Aldrich Introduces MISSION(R) In VIVO QUALITY and iScale Oligos(TM) siRNA, a Superior Quality siRNA Designed for RNAi Research in Animal Models
3. Stem Cell Sciences Licenses Stem Cell Technology to Leading Provider of Genetically Modified Models for Pharmaceutical Research
4. Antiangiogenic Role of 2ME2 Demonstrated in Rheumatoid Arthritis Models
5. Michigan Tech scientist models molecular switch
6. Microsoft scientist highlights urgent need for new computer models to address climate change
7. Study Shows Coronado Biosciences Bcl-2 Inhibitor, Apogossypol, is More Efficacious, Less Toxic than Gossypol in Animal Models
8. Data on WaferGens SmartChip(TM) System Presented at 16th International Molecular Medicine Tri-Conference
9. PharmAthene Presents Data for SparVax(TM) and Valortim(R), a Novel Vaccine and Anti-Toxin for the Prevention and Treatment of Anthrax Infection at the 7th Annual ASM Biodefense Meeting
10. Abbott to Present at Barclays Global Healthcare Conference
11. Sirius Genomics to Present at Invest Northwest Conference
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/23/2016)... ... 23, 2016 , ... UAS LifeSciences, one of the leading ... UP4™ Probiotics, into Target stores nationwide. The company, which has been manufacturing high ... its list of well-respected retailers. This list includes such fine stores as Whole ...
(Date:6/23/2016)... , June 23, 2016 Houston ... with the Cy-Fair Sports Association to serve as ... the agreement, Houston Methodist Willowbrook will provide sponsorship ... and connectivity with association coaches, volunteers, athletes and ... with the Cy-Fair Sports Association and to bring ...
(Date:6/23/2016)... 23, 2016   EpiBiome , a precision microbiome ... in debt financing from Silicon Valley Bank (SVB). The ... to advance its drug development efforts, as well as ... "SVB has been an incredible strategic partner to ... traditional bank would provide," said Dr. Aeron Tynes ...
(Date:6/23/2016)... LOUISVILLE, Ky. , June 23, 2016 /PRNewswire/ ... from two Phase 1 clinical trials of its ... double-blind, placebo-controlled, single and multiple ascending dose studies ... and pharmacodynamics (PD) of subcutaneous injection in healthy ... APL-2 subcutaneously (SC) either as a single dose ...
Breaking Biology Technology:
(Date:5/3/2016)... Lithuania , May 3, 2016  Neurotechnology, ... released the MegaMatcher Automated Biometric Identification System ... of large-scale multi-biometric projects. MegaMatcher ABIS can process ... accuracy using any combination of fingerprint, face or ... MegaMatcher SDK and MegaMatcher Accelerator ...
(Date:4/19/2016)... 20, 2016 The new GEZE ... compact web-based "all-in-one" system solution for all door components. ... or the door interface with integration authorization management system, ... systems. The minimal dimensions of the access control and ... building installations offer considerable freedom of design with regard ...
(Date:3/31/2016)...   LegacyXChange, Inc. ... LegacyXChange is excited to release its first ... be launched online site for trading 100% guaranteed authentic ... also provide potential shareholders a sense of the value ... industry that is notorious for fraud. The video is ...
Breaking Biology News(10 mins):