Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Nanocomposites toughen up


An alternative fabrication route improves the properties of aluminum-based nanocomposites with great potential for vehicles of the future

One challenge in producing strong, elastic and hard-wearing nanocomposites is obtaining an even distribution of the nanoparticles in the metal matrix. Now, researchers at A*STAR have used a process known as friction stir processing (see image) to produce an evenly distributed mix of nanosized aluminum oxide (Al2O3) particles in aluminum1. Their technique is a viable new method for manufacturing nanocomposites and has exciting potential for the car, space and defense industries.

Schematic diagram of friction stir processing, a method used to improve the hardness and tensile strength of aluminum-based nanocomposites.

Copyright : © 2014 A*STAR Singapore Institute of Manufacturing Technology

“Current powder metallurgy or liquid processing methods fail to achieve uniform processing,” says research leader Junfeng Guo, who is from the A*STAR Singapore Institute of Manufacturing Technology.

Guo’s team drilled hundreds of 1-millimeter-diameter holes into the surface of a thin sheet of an aluminum alloy. They then injected a slurry of aluminum oxide nanoparticles into the holes and heated the sheet in an oven. After cooling the sheet, the team plunged a rotating tool into it — this is the friction stir processing step. The friction generated between the tool and the sheet caused the material to plasticize. The tool was moved around to ensure that the entire sheet was plasticized.

Placing the nanoparticles in the sheet prior to the friction stir processing step significantly increased the concentration of nanoparticles in the composite. “It also reduced the amount of airborne particles produced during powder placement and friction stir processing,” explains Guo.

The team used scanning electron microscopy to check two key properties that influence the strength of nanocomposites. They first demonstrated that the nanoparticles were uniformly dispersed, which means the material has no weak points. They also found that the grains or crystals of the aluminum matrix that recrystallized after being plasticized were extremely small; smaller aluminum matrix grains can flow past each other more smoothly than larger particles, enhancing the strength of the material.

By measuring the grain size after performing friction stir processing with and without the Al2O3 nanoparticles, the team showed that the nanoparticles contributed to the reduction in grain size.

The best nanoparticle distribution and smallest aluminum alloy grains were obtained after passing the rotating tool through the sheet four times. The team then demonstrated that the composite made in this way had significantly improved hardness and tensile strength compared to untreated aluminum alloy sheets.

“We plan to continue this research to further improve the mechanical and thermal properties as well as the wear resistance of the nanocomposites,” says Guo. “Eventually, we aim to commercialize our technology to aid local industry.”

Guo, J. F., Liu, J., Sun, C. N., Maleksaeedi, S., Bi, G. et al. Effects of nano-Al2O3 particle addition on grain structure evolution and mechanical behaviour of friction-stir-processed Al. Materials Science and Engineering: A 602, 143–149 (2014) |

Associated links

A*STAR Research | Research SEA News
Further information:

More articles from Automotive Engineering:

nachricht New algorithm for optimized stability of planar-rod objects
11.08.2016 | Institute of Science and Technology Austria

nachricht Automated driving: Steering without limits
05.02.2016 | FZI Forschungszentrum Informatik am Karlsruher Institut für Technologie

All articles from Automotive Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>