Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Fitter Frames: Nanotubes Boost Structural Integrity of Composites

Researchers at Rensselaer have discovered a new technique for provoking unusual crazing behavior in epoxy composites. The crazing, which causes the composite to deform into a network of nanoscale pillar-like fibers that bridge together both sides of a crack and slow its growth, could lead to tougher, more durable components for aircraft and automobiles.
Researchers at Rensselaer have discovered a new technique for provoking unusual crazing behavior in epoxy composites. The crazing, which causes the composite to deform into a network of nanoscale pillar-like fibers that bridge together both sides of a crack and slow its growth, could lead to tougher, more durable components for aircraft and automobiles.

Abstract:
New research finding could lead to more durable aircraft, automotive components

Fitter Frames: Nanotubes Boost Structural Integrity of Composites

Troy, NY | Posted on March 27th, 2009

A new research discovery at Rensselaer Polytechnic Institute could lead to tougher, more durable composite frames for aircraft, watercraft, and automobiles.

Epoxy composites are increasingly being incorporated into the design of new jets, planes, and other vehicles. Composite material frames are extremely lightweight, which lowers the overall weight of the vehicle and boosts fuel efficiency. The downside is that epoxy composites can be brittle, which is detrimental to its structural integrity.

Professor Nikhil Koratkar, of Rensselaer's Department of Mechanical, Aerospace, and Nuclear Engineering, has demonstrated that incorporating chemically treated carbon nanotubes into an epoxy composite can significantly improve the overall toughness, fatigue resistance, and durability of a composite frame.

When subjected to repetitive stress, a composite frame infused with treated nanotubes exhibited a five-fold reduction in crack growth rate as compared to a frame infused with untreated nanotubes, and a 20-fold reduction when compared to a composite frame made without nanotubes.

This newfound toughness and crack resistance is due to the treated nanotubes, which enhance the molecular mobility of the epoxy at the interface where the two materials touch. When stressed, this enhanced mobility enables the epoxy to craze - or result in the formation of a network of pillar-like fibers that bridge together both sides of the crack and slow its growth.

"This crazing behavior, and the bridging fibers it produces, dramatically slows the growth rate of a crack," Koratkar said. "In order for the crack to grow, those fibers have to first stretch, deform plastically, and then break. It takes a lot of energy to stretch and break those fibers, energy that would have otherwise gone toward enlarging the crack."

Results of the study were published this week in the journal Small.

Epoxy composites infused with carbon nanotubes are known to be more resistant to cracks than pure epoxy composites, as the nanotubes stitch, or bridge, the two sides of the crack together. Infusing an epoxy with carbon nanotubes that have been functionalized, or treated, with the chemical group amidoamine, however, results in a completely different bridging phenomenon.

At the interface of the functionalized nanotubes and the epoxy, the epoxy starts to craze, which is a highly unusual behavior for this particular type of composite, Koratkar said. The epoxy deforms, becomes more fluid, and creates connective fibers up to 10 microns in length and with a diameter between 100 nanometers and 1,000 nanometers.

"We didn't expect this at all. Crazing is common in certain types of thermoplastic polymers, but very unusual in the type of epoxy composite we used," Koratkar said. "In addition to improved fatigue resistance and toughness, the treated nanotubes also enhanced the stiffness, hardness, and strength of the epoxy composite, which is very important for structural applications."

Koratkar said the aircraft, boat, and automobile industries are increasingly looking to composites as a building material to make vehicle frames and components lighter. His research group plans to further investigate crazing behavior in epoxy composites, in order to better understand why the chemical treatment of nanotubes initiates crazing.

Co-authors of the paper include Rensselaer Associate Professor Catalin Picu, of the Department of Mechanical, Aerospace, and Nuclear Engineering; Rensselaer doctoral students Wei Zhang and Iti Srivastava; and Yue-Feng Zhu, professor in the Department of Mechanical Engineering at Tsinghua University in China.

Visit Koratkar's Web site http://www.eng.rpi.edu/mane/faculty_details.cfm?facultyID=koratn&type=research for more information on his nanomaterials research.

####

About Rensselaer Polytechnic Institute
RPI is widely recognized for the effectiveness of its hands-on approach to undergraduate education. Rensselaer’s classrooms are a model for intellectual engagement and the interaction of students and faculty.

In both curriculum reform and creative use of new teaching techniques and technologies, Rensselaer’s leadership in interactive learning has helped to further transform the way we teach and learn.

Contacts:
Jason B. Gorss
Manager of Media Relations
(518) 276-6098

Copyright © Rensselaer Polytechnic Institute

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

News and information

Researchers develop new way to manufacture nanofibers May 21st, 2015

Nanotherapy effective in mice with multiple myeloma May 21st, 2015

Turn that defect upside down: Twin boundaries in lithium-ion batteries May 21st, 2015

INSIDDE: Uncovering the real history of art using a graphene scanner May 21st, 2015

Marine/Watercraft

Enhanced Graphene Components for Next Generation Racing Yacht March 5th, 2015

BRAAVOO will design an unmanned surveying vessel and marine buoy that carry biosensors to monitor marine pollutants November 12th, 2014

First Observation of Electronic Structure in Ag-Rh Alloy Nanoparticles Having Hydrogen Absorbing: Storage Property –Attempting to solve the mystery of why Ag-Rh alloy nanoparticles have a similar property to Pd– October 30th, 2014

Engineered proteins stick like glue — even in water: New adhesives based on mussel proteins could be useful for naval or medical applications September 22nd, 2014

Possible Futures

Simulations predict flat liquid May 21st, 2015

Nature inspires first artificial molecular pump: Simple design mimics pumping mechanism of life-sustaining proteins found in living cells May 19th, 2015

NNCO and Museum of Science Fiction to Collaborate on Nanotechnology and 3D Printing Panels at Awesome Con May 19th, 2015

Quantum 'gruyères' for spintronics of the future: Topological insulators become a little less 'elusive' May 12th, 2015

Nanotubes/Buckyballs/Fullerenes

Researchers develop new way to manufacture nanofibers May 21st, 2015

Sandia researchers first to measure thermoelectric behavior by 'Tinkertoy' materials May 20th, 2015

Cotton fibres instead of carbon nanotubes May 9th, 2015

A better way to build DNA scaffolds: McGill researchers devise new technique to produce long, custom-designed DNA strands May 6th, 2015

Announcements

Researchers develop new way to manufacture nanofibers May 21st, 2015

Nanotherapy effective in mice with multiple myeloma May 21st, 2015

Turn that defect upside down: Twin boundaries in lithium-ion batteries May 21st, 2015

INSIDDE: Uncovering the real history of art using a graphene scanner May 21st, 2015

Automotive/Transportation

Wearables may get boost from boron-infused graphene: Rice U. researchers flex muscle of laser-written microsupercapacitors May 18th, 2015

ORNL demonstrates first large-scale graphene fabrication May 14th, 2015

Penn and UC Merced researchers match physical and virtual atomic friction experiments May 8th, 2015

Silicon Storage Technology and GLOBALFOUNDRIES Announce Qualification of Automotive Grade 55nm Embedded Flash Memory Technology May 5th, 2015

Aerospace/Space

ORNL demonstrates first large-scale graphene fabrication May 14th, 2015

International and U.S. Students and Teachers Headed to Toronto for 34th Annual International Space Development Conference®: Students competed in prestigious NSS-NASA Ames Space Settlement Design Contest May 9th, 2015

'Microcombing' creates stronger, more conductive carbon nanotube films May 5th, 2015

Iranian Scientists Present Model to Study Mechanical Vibrations of Structures Containing Nanocomposites May 5th, 2015

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