Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researcher describes new type of strong, lightweight metallic material

08.03.2005


A new type of laminate performed spectacularly in depth-of-penetration ballistics tests, but its greatest potential may derive from its ability to be tailored to meet specific engineering requirements



An engineering professor at the University of California, San Diego has described in the March issue of JOM (the Journal of the Minerals, Metals and Materials Society) the unique properties of a new type of metallic laminate that can serve as armor and as a replacement for beryllium, a strong but toxic metal commonly used in demanding aerospace applications.

"The new material we developed is environmentally safe, and while its stiffness equals that of steel, it’s only half as dense," said Kenneth S. Vecchio, author of the paper and a professor of mechanical and aerospace engineering in UCSD’s Jacobs School of Engineering. "It performs spectacularly in our depth-of-penetration ballistics tests, but we think its greatest potential may derive from its unique ability to have its structure and properties tailored to meet a wide variety of application-specific engineering requirements."


The new material is made primarily of two lightweight metals. Vecchio alternated layers of aluminum and titanium alloy foils, and compressed and heated them in an inexpensive energy-conserving process. The resulting reaction generated a laminate with two layers: a hard ceramic-like "intermetallic" layer of titanium aluminide, and a pliable layer of residual titanium alloy. The layers can be stacked like 1-millimeter-thick pages of a book, and even contoured into desired shapes prior to heating.

The laminate architecture was chosen by Vecchio to mimic the internal structure of the tough shell of the red abalone. This science-mimicking-biology approach is one of an increasing number of biomimetic research efforts at the Jacobs School of Engineering. Faculty members are studying structural and functional designs of everything from mollusk shells and bird bills to sea urchin spines and other biocomposites in the development of new smart materials and devices.

The red abalone, a seaweed-eating snail prized as a source of mother-of-pearl jewelry, is found off the coast of California. The mollusk makes its dome-shaped home by slowly adding layers of brittle calcium carbonate, each about one-thousandth the thickness of a strand of human hair, between even thinner layers of a stretchy protein adhesive.

"The intermetallic phase of titanium aluminide is the complement of the mollusk’s hard calcium carbonate phase, and the titanium alloy layer mimics the abalone shell’s compliant protein layers," said Vecchio.

In order to test the bullet-stopping capability of his new material, Vecchio fired a heavy tungsten alloy rod into a three-quarters-inch (2 centimeters) thick sample at a velocity of about 2,000 mph (900 meters per second). The rod penetrated only half the thickness of the test sample. Vecchio said the laminate performs surprisingly well as armor and has potential as a structural metal.

He said other types of metallic foils containing vanadium, chromium, manganese, nickel, cobalt, and iron have been successfully fabricated into laminates using the same stacked foil technique. "We’ve only begun to explore the possible combinations and potential uses of these promising new materials," said Vecchio.

He described in his paper the production of cavities within his laminate layers, which were made by cutting out parts of the foil prior to heating. In one case, he filled cavities with steel beads, which were free to bounce within their confines and act as highly efficient vibration dampeners. "This vibration-dampening characteristic could be extremely valuable in jet engines and other high-performance applications prone to noisy vibration," said Vecchio.

It’s also possible to include electrical pathways within the laminates by embedding metal or ceramic wires or fibers during fabrication, and those components could both strengthen the material and act as built-in sensors. In addition, Vecchio said the laminates could be further enhanced with the addition of materials that generate an electric charge when mechanically deformed. Conversely, these so-called piezoelectric materials also deform when an electric field is applied to them.

Rex Graham | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Materials Sciences:

nachricht Barely scratching the surface: A new way to make robust membranes
13.12.2018 | DOE/Argonne National Laboratory

nachricht Topological material switched off and on for the first time
11.12.2018 | ARC Centre of Excellence in Future Low-Energy Electronics Technologies

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Success at leading conference on silicon materials science and technology in Japan

13.12.2018 | Awards Funding

NSF-supported scientists present new research results on Earth's critical zone

13.12.2018 | Earth Sciences

Barely scratching the surface: A new way to make robust membranes

13.12.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>