Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanostructured Alloying with Oxygen

09.04.2018

Latest findings published in Nature Communications

Severe plastic deformation and powder processing techniques are used to produce nanostructured materials with tailor-made compositions and without the effort of precasting. They allow the production of novel metallic nanocrystalline materials by mechanically alloying immiscible elements.


Dr. Jazmin Duarte did atom probe measurements to characterize the oxigen distribution in the alloy.

Max-Planck-Institut für Eisenforschung GmbH

Oxide contamination during the processing of these powders still hinders this method to be applied in industry comprehensively. Meanwhile it is also known that oxygen could be used beneficially to influence morphology, mechanical properties and thermal stability of nanostructured alloys.

Up to now this possibility is still not used as it is unclear how oxide behaves during annealing. Scientists from the Max-Planck-Institut für Eisenforschung (MPIE), the Austrian Erich Schmid Institute of Material Science, the Universities Leoben and Graz (Austria) and the Chinese Hubei University analysed in-situ copper-iron alloys during annealing to find out when and how oxide is formed and how it can be used to strengthen nanocrystalline materials. They published their latest findings in Nature Communications.

“By combining different experimental methods and density-functional theory calculations, we studied the thermal behaviour of oxygen in nanocrystalline copper-iron alloys which were fabricated under severe deformation and high pressure. During the heating process but still at very low temperatures, oxidation starts, leading to the formation of nanosized copper and iron oxides inside grains. Later in the heating process the metastable copper-iron solid solution decomposes into iron- and copper-rich phases.”, explains Dr. Jazmin Duarte, senior researcher in the department “Structure and Nano-/Micromechanics of Materials”.

The copper and iron oxides and iron precipitates grow with annealing temperature, till they reach approximately 10 nanometres. Both oxide distributions are almost identical, which means that oxygen diffuses to one specific area during heating, simultaneously triggering the nucleation processes of oxides.

“For the first time a direct observation of oxide formation in single-phase copper-iron alloys was possible. We also did several comparison studies and ex situ analyses to make sure that neither the electron beam of the transmission electron microscope nor the sample size have an influence on the oxidation and precipitation processes. This new insights give us the possibility of manipulating mechanical properties by including oxygen into nanocrystalline alloys. Oxygen which was formerly seen as contamination to be avoided, can now be used as an ingredient to form advanced, nanostructured alloys.”, explains Prof. Gerhard Dehm, director at the MPIE.

The scientists are now further studying the mechanisms by which oxygen can be introduced into the alloys and how the microstructure and consequently the mechanical behaviour are affected by an increased content of dissolved oxygen. Such tailor-made microstructures could be then used to engineer oxide strengthened nanocrystalline materials for specific applications.

Original publication:
J. Guo, G. Haberfehlner, J. Rosalie, L. Li, M. J. Duarte, G. Kothleitner, G. Dehm, Y. He, R. Pippan, Z. Zhang: In situ atomic-scale observation of oxidation and decomposition processes in nanocrystalline alloys. Nature Communications, (2018)9:946, DOI: 10.1038/s41467-018-03288-8

Weitere Informationen:

https://www.mpie.de/3785097/nanostructured-alloying-with-oxygen

Yasmin Ahmed Salem M.A. | Max-Planck-Institut für Eisenforschung GmbH

More articles from Machine Engineering:

nachricht Integrating One’s Sights on the Factor of 10: “futureAM – Next Generation Additive Manufacturing”
26.10.2018 | Fraunhofer-Institut für Lasertechnik ILT

nachricht BladeFactory research project: Quicker rotor blade production and a higher quality result
12.10.2018 | Fraunhofer-Institut für Windenergiesysteme IWES

All articles from Machine Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

New materials: Growing polymer pelts

19.11.2018 | Materials Sciences

Earthquake researchers finalists for supercomputing prize

19.11.2018 | Information Technology

Controlling organ growth with light

19.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>