New spin friction-stir

New spin on friction-stir

12:18 PM, 30th July 2011
New spin on friction-stir
ORNL team (L to R) Zhili Feng, Stan David, Alan Frederic display a length of wire more than 15 ft long fabricated with the friction-stir extrusion method, using Mg-Al alloy feed stock. Friction-stir extrusion is an energy-efficient method for making wire from high-temperature, recyclable materials.

OAK RIDGE, US: Researchers Zhili Feng, Alan Frederic and Stan David in Oak Ridge National Laboratory’s Materials S&T division have made significant progress toward a new metal processing technique, called friction-stir extrusion, that could represent a major advance in converting recyclable materials - such as alloys of aluminum, magnesium and titanium alloys and even high-temperature superconductors - to useful products.

The process also represents a step forward in energy-efficient industrial processes as it eliminates the melting step in conventional metal recycling and processing. The friction-stir method, as the name implies, derives its heat from spinning metal against metal and direct conversion of mechanical energy to thermal energy.

The ORNL team produced a solid wire of a magnesium-aluminum alloy from machined chips, eliminating the energy and labour intensive processes of melting and casting.

“This process is simple. You get the product form that you want by just using the frictional heat,” said Stan David, an ORNL, Retiree and Consultant who once led the division’s Materials Joining group.

The new approach provides an opportunity to efficiently produce highly engineered structural and functional materials. Friction extrusion can be developed into metal recycling process of steels, Al alloys, and other recyclable metals. The impact of economically producing nano engineered creep resistance Al conductors in large quantity will be enormous for the power transmission industry.

“The process of melting and casting can destroy the properties of a highly ordered, novel material. Because friction-stir only takes the material up to ‘plasticizing’ temperatures, the properties of the material are not much affected,” said Zhili Feng, who leads the ORNL group.

The extrusion process follows the same principle of the friction-stir welding, in which a rapidly spinning tool is applied to the metal, heating it until it becomes soft, but not melted. Because the material is still in its solid state when it is extruded, it suffers none of the degradation and transformation that would occur with actual melting.

Wayne Thomas, who pioneered the friction stir technology at The Welding Institute in England, said ORNL has proved the basic principle of a new technique that could be key to working with advanced alloys, including high-temperature superconductors.

Friction-stir extrusion has potential to be a low-cost method. Also the process requires only 10 to 20 per cent of the energy required for conventional melting with potential saving of more than 80 per cent.

The team credits DOE’s Industrial Technologies Programme for a capital equipment investment and programmatic funding. Seeing industry interest, the ORNL team is working with Southwire Company, a major international electric cable company, for technology development.

“The collaborative research between Southwire and ORNL using friction extrusion to synthesize new alloys has yielded promising results. We are excited, that the continued success of this project may result in large scale production of innovative wire and cable products,” said Kiran Manchiraju, Director, Southwire Company.

(C) Oak Ridge National Laboratory News



Your Comments (Up to 2000 characters)
Please respect our community and the integrity of its participants. WOC reserves the right to moderate and approve your comment.

Related News

Dow agrees with US EPA to pay $2.5 million to settle violations

  MIDLAND, US: The Dow Chemical Company’s Michigan operations has reached a comprehensive settlement agreement with the United States Envi ...

Read more
ACS enables new subject-based categorization of content

WASHINGTON, US: The ACS Publications and Chemical Abstracts Service (CAS) divisions of the American Chemical Society (ACS) announced jointly the integ ...

Read more
LyondellBasell posts higher income but diluted earnings per share

• Net income of $804 million; Diluted earnings per share of $1.38. • Quarterly EBITDA of $1,553 million; 11 per cent increase fro ...

Read more
UK government sets aside 1000 places for top researchers

LONDON, UNITED KINGDOM: The UK chemistry sector has given a mostly cool response to a government scheme to attract top chemists, chemical engineers an ...

Read more
Dow reports strong results on plastics, chemicals performance

· Dow reported earnings of $0.84 per share. This compares with reported earnings of $0.50 per share in the same period last year. The comp ...

Read more
AkzoNobel posts diluted income on raw material cost rise

  · Revenue up 8 per cent to €4.1 billion, driven by volume and pricing. · Raw material inflation, challenging tra ...

Read more uses cookies to ensure that we give you the best experience on our website. By using this site, you agree to our Privacy Policy and our Terms of Use. X