Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > World’s smallest universal material testing system

Abstract:
Micromachine makes possible the investigation of nanomechanics phenomena in real time

World’s smallest universal material testing system

Evanston, Ill | September 23, 2005

The design, development and manufacturing of revolutionary products such as the automobile, airplane and computer owe a great deal of their success to the large-scale material testing systems (MTS) that have provided engineers and designers with a fundamental understanding of the mechanical behavior of various materials and structures.

In the world of nanotechnology, however, where the mechanical characterization of materials and structures takes place on the scale of atoms and molecules, the existing material testing systems are useless. The development of a universal nanoscale material testing system (n-MTS), which could fit in existing electron microscopes (instruments that can magnify images approximately one million times) and possess the resolution and accuracy needed to mechanically test nanoscale objects, has been a major challenge within the scientific community.

Now researchers at Northwestern University have designed and built the first complete micromachine that makes possible the investigation of nanomechanics phenomena in real time. The findings are published online this week by the Proceedings of the National Academy of Sciences (PNAS). The machine, which can fit in tiny spaces as required by in situ transmission electron microscopy (TEM), successfully characterized the mechanical properties of nanowires and carbon nanotubes.

The n-MTS developed by Horacio D. Espinosa, professor of mechanical engineering, and his colleagues consists of an actuator and a load sensor fabricated by means of micro technology (a derivative of the computer industry). The load sensor is based on differential capacitive sensing, which provides a load resolution of about 10 nano Newtons. This is the first nanoscale material testing system that provides continuous observation of specimen deformation and failure with sub-nanometer resolution while simultaneously measuring electronically the applied forces with nano-Newton resolution. The integration of electro-mechanical and thermo-mechanical components at the micro scale made the achievement possible.

One of the challenges overcome by the University researchers was the integration of micro-electro-mechanical systems (MEMS) and circuits for measurement of electronic signals. They solved this problem by using a double-chip architecture consisting of a MEMS chip and a microelectronic sensing chip.

Another challenge overcome by the team was the mounting of individual nanostructures on the testing device. Using a nanomanipulator inside a dual-beam scanning electron microscope and focused ion beam apparatus (a new tool available to nanoscientists) the researchers picked up nanostructures, cut them to the desired length and nanowelded the structures onto the n-MTS using electron-beam-induced deposition of platinum.

As reported in the PNAS paper, the system capabilities were demonstrated by in situ electron microscopy testing of free-standing polysilicon films, metallic nanowires and carbon nanotubes (CNTs). Espinosa’s team achieved the first real-time instrumented in situ transmission electron microscopy observation of CNTs failure under tensile loading.

In 1959, Nobel Laureate Richard Feynman delivered a talk at the California Institute of Technology entitled “There is Plenty of Room at the Bottom” in which he envisioned the possibility of making very small machines. “Our MEMS-based nanoscale material testing system represents another milestone along the path of miniaturization anticipated by Feynman,” said Espinosa. “We expect it will have a similar impact and produce the same level of opportunities as the development of the universal testing machine had in the last century.”

The n-MTS can be potentially applied to characterize the mechanical, thermal and electro-mechanical properties not only of nanowires and nanotubes but also of a large number of organic materials, including DNA, proteins and nanofibers.

In addition to Espinosa, the other author on the PNAS paper is graduate student Yong Zhu. The research was supported by the National Science Foundation under Awards No. DMR-0315561 and CMS 0120866. Nanomanipulation was carried out in the Center for Microanalysis of Materials at the University of Illinois, which is partially supported by the U.S. Department of Energy under grant DEFG02-96-ER45439.

####
Source contact: Horacio Espinosa at 847-467-5989 or espinosa@northwestern.edu
Contact:
Megan Fellman
(847) 491-3115
fellman@northwestern.edu

Copyright © Northwestern University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Possible Futures

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers discern the shapes of high-order Brownian motions November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Open Materials Development Will Be Key for HP's Success in 3D Printing: HP can make a big splash in 3D printing, but it needs to shore up technology claims and avoid the temptation of the razor/razor blade business model in order to flourish November 11th, 2014

Materials/Metamaterials

Aculon Hires New Business Development Director December 19th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

Graphene Applied in Production of Recyclable Electrodes December 13th, 2014

Announcements

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Tools

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE