Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Scientists Discover Networks of Metal Nanoparticles Are Culprits in Alloy Corrosion

Oxide scales are supposed to protect alloys from extensive corrosion, but scientists at U.S. Department of Energy's Argonne National Laboratory have discovered metal nanoparticle chinks in this armor.

Oxide scales develop on the outer surface of alloys at high temperatures creating a protective barrier that keeps destructive carbon-bearing molecules from slipping into the alloy. The diffusion of carbon into oxide scales should be negligible, but studies have shown that carbon can sneak through the oxide line of defense leading to brittleness and corrosion.

"The United States loses four percent of the gross national product due to alloy corrosion," Argonne Distinguished Fellow Ken Natesan said. "A network of continuous metal nanoparticles allow the carbon to dissolve and diffuse through the protective oxide scales without the need of a crack or a pore."

It was commonly believed that carbon-containing molecules escaped into cracks or pores in the oxide scales, but using three separate techniques -- nanobeam x-ray analysis at the Advanced Photon Source, magnetic force microscopy at the Center for Nanoscale Materials and scanning electron microscopy at the Electron Microscopy Center -- Natesan, along with Argonne scientists Zuotao Zeng, Seth Darling and Zhonghou Cai, discovered networks of iron and nickel nanoparticles embedded within the oxide scales.

Carbon can easily diffuse through the metals and create a path for carbon atom transport which does not involve defects in the scale.

"By examining the oxide scale, we find the metal nanoparticles," Zeng said. "If they are eliminated we can create a more corrosion-resistant and longer lasting alloy."

Based on the study, ANL has developed laboratory size batches of materials that exhibit as much as ten times longer life than commercial alloys with similar chromium contents, Natesan said. At present, 50-lb batches of the alloys have been cast successfully by an alloy manufacturer and will be commercialized in due course. The ANL-developed alloys are of considerable interest to the chemical, petrochemical, and refining industry.

The findings might also have broad influence on not only metal dusting and carburization, but also in other research areas such as alloy development and surface coatings for high-temperature fuel cell applications.

Funding for this research was provided by the U.S. Department of Energy, Office of Industrial Technologies. The Argonne scientific user facilities such as the Advanced Photon Source, Electron Microscopy Center and Center for Nanoscale Materials are supported by the U.S. Department of Energy, Office of Science.

A paper based on this work has been published recently in Nature Materials.

Argonne National Laboratory brings the world's brightest scientists and engineers together to find exciting and creative new solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

Brock Cooper | Newswise Science News
Further information:

More articles from Materials Sciences:

nachricht Researchers demonstrate existence of new form of electronic matter
15.03.2018 | University of Illinois at Urbana-Champaign

nachricht Boron can form a purely honeycomb, graphene-like 2-D structure
15.03.2018 | Science China Press

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>