Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > What makes superalloys super - hierarchical microstructure of a superalloy

The image shows the three-dimensional reconstruction of an atom probe measurement. The γ matrix (purple) can be seen surrounding the cuboidal γ’ precipitates (green). Only a few nanometre-sized γ platelets can be seen in the γ’ precipitates. Atom probe tomography allows a site specific analysis of the structure at the atomic scale and reveals the chemical composition in measurements of individual areas. Image: HZB
The image shows the three-dimensional reconstruction of an atom probe measurement. The γ matrix (purple) can be seen surrounding the cuboidal γ’ precipitates (green). Only a few nanometre-sized γ platelets can be seen in the γ’ precipitates. Atom probe tomography allows a site specific analysis of the structure at the atomic scale and reveals the chemical composition in measurements of individual areas.

Image: HZB

Abstract:
Researchers have observed for the first time in detail how a hierarchical microstructure develops during heat treatment of a superalloy

What makes superalloys super - hierarchical microstructure of a superalloy

Berlin, Germany | Posted on January 14th, 2014

Materials in high-performance turbines have to withstand not only powerful mechanical forces, they also have to maintain their chemical and mechanical properties almost up to their melting points. For this reason, turbine manufacturers have employed special nickel-based high-performance alloys for decades. New work from Helmholtz-Zentrum Berlin für Materialien and Energie (HZB) now shows in detail how new phases in a nickel-based alloy form and evolve, providing clues to how high-performance alloys could be improved. Doctoral student Florian Vogel and Dr. Nelia Wanderka from the HZB Institute of Applied Materials have elegantly combined two methods to accomplish this: transmission electron microscopy (TEM) and atom probe tomography (APT), which they carried out in collaboration with colleagues from the University of Münster.

They were interested in a phase separation phenomenon that has been known for around 50 years, but could neither be precisely observed nor understood until now: The microstructure of nickel-based alloys changes under controlled ageing or heat treatment and in the classical two-phase microstructure new phases are initially formed. Wanderka and Vogel were able to precisely observe the phase separation process on the atomic scale for the first time.

To do so, they simulated the ageing process of the alloy by heat treating it for different periods. They documented how the microstructure changed during the ageing of the alloy using micrographs from the transmission electron microscope. Whereas the classical two-phase microstructure consists of cuboid γ' precipitates embedded in a so called γ-matrix, during heat treatment, spherical γ particles initially form in the γ' precipitates of the alloy, then further coalesce into plates that finally split the γ' precipitates. The thermo-mechanical properties of these types of alloys depend largely on the stability of this γ/γ´ microstructure.

In order to determine the atomic constituents of the individual phases, but primarily to learn about the formation and make-up of the poorly understood γ particle, Vogel and Wanderka investigated the aged samples using atom probe tomography at the University of Münster. They succeeded in reconstructing the atomic lattice of the samples layer by layer and determining the composition of all phases, so that they could explain the chemical evolution of the γ particles.

"Until now, it was assumed that splitting of the γ' precipitates refines the microstructure during ageing, which would be beneficial for the alloy's stability under thermo-mechanical load. We were able to show that this is not correct. The microstructure indeed changes considerably, but it is not improved by the splitting however. We were actually able to correlate the best mechanical properties with the presence of spherical or plate-like γ particles and not with the later stages after splitting of the γ' precipitates has taken place", explains Florian Vogel. Nelia Wanderka adds: "If we want to improve the stability of the microstructure and thus the thermomechanical properties of the alloy, we need to be sure that the γ' precipitates are not split by the γ particles, but instead remain intact through appropriate heat treatment and composition of the alloy. Atom probe tomography helps us in understanding the role of the alloying elements in the formation and growth of the γ particles. From this, we can learn how to influence these processes."

####

For more information, please click here

Contacts:
Dr. Nelia Wanderka

49-308-062-42079

Florian Vogel
Tel (030) 8062 - 43217
Fax (030) 8062 - 43059


Dr. Antonia Rötger
Tel (030) 8062 - 43733
Fax (030) 8062 - 42998

Copyright © Helmholtz-Zentrum Berlin für Materialien und Energie

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

The work was published 20 Dec 2013 in the distinguished journal Nature Communications. doi:10.1038/ncomms3955:

Related News Press

News and information

Simple attraction: Researchers control protein release from nanoparticles without encapsulation: U of T Engineering discovery stands to improve reliability and fabrication process for treatments to conditions such as spinal cord damage and stroke May 28th, 2016

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Doubling down on Schrödinger's cat May 27th, 2016

Deep Space Industries and SFL selected to provide satellites for HawkEye 360’s Pathfinder mission: The privately-funded space-based global wireless signal monitoring system will be developed by Deep Space Industries and UTIAS Space Flight Laboratory May 26th, 2016

Imaging

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Discoveries

Simple attraction: Researchers control protein release from nanoparticles without encapsulation: U of T Engineering discovery stands to improve reliability and fabrication process for treatments to conditions such as spinal cord damage and stroke May 28th, 2016

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Doubling down on Schrödinger's cat May 27th, 2016

Finding a new formula for concrete: Researchers look to bones and shells as blueprints for stronger, more durable concrete May 26th, 2016

Materials/Metamaterials

Thermal modification of wood and a complex study of its properties by magnetic resonance May 26th, 2016

Finding a new formula for concrete: Researchers look to bones and shells as blueprints for stronger, more durable concrete May 26th, 2016

Revealing the nature of magnetic interactions in manganese oxide: New technique for probing local magnetic interactions confirms 'superexchange' model that explains how the material gets its long-range magnetic order May 25th, 2016

Diamonds closer to becoming ideal semiconductors: Researchers find new method for doping single crystals of diamond May 25th, 2016

Announcements

Simple attraction: Researchers control protein release from nanoparticles without encapsulation: U of T Engineering discovery stands to improve reliability and fabrication process for treatments to conditions such as spinal cord damage and stroke May 28th, 2016

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Doubling down on Schrödinger's cat May 27th, 2016

Deep Space Industries and SFL selected to provide satellites for HawkEye 360’s Pathfinder mission: The privately-funded space-based global wireless signal monitoring system will be developed by Deep Space Industries and UTIAS Space Flight Laboratory May 26th, 2016

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Simple attraction: Researchers control protein release from nanoparticles without encapsulation: U of T Engineering discovery stands to improve reliability and fabrication process for treatments to conditions such as spinal cord damage and stroke May 28th, 2016

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Doubling down on Schrödinger's cat May 27th, 2016

Finding a new formula for concrete: Researchers look to bones and shells as blueprints for stronger, more durable concrete May 26th, 2016

Tools

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

More light on cancer: Scientists created nanoparticles to highlight cancer cells May 21st, 2016

Nanotubes are beacons in cancer-imaging technique: Rice University researchers use spectral triangulation to pinpoint location of tumors May 21st, 2016

Automotive/Transportation

Technique improves the efficacy of fuel cells: Research demonstrates a new phase transition from metal to ionic conductor May 18th, 2016

A View Through Wood Shows Futuristic Applications: Transparent wood made at UMD could create new windows, cars and solar panels May 5th, 2016

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

New spin Seebeck thermoelectric device with higher conversion efficiency created April 26th, 2016

Aerospace/Space

Deep Space Industries and SFL selected to provide satellites for HawkEye 360’s Pathfinder mission: The privately-funded space-based global wireless signal monitoring system will be developed by Deep Space Industries and UTIAS Space Flight Laboratory May 26th, 2016

Rice de-icer gains anti-icing properties: Dual-function, graphene-based material good for aircraft, extreme environments May 23rd, 2016

We’ll Leave the Lights On For You: Photonics advances allow us to be seen across the universe, with major implications for the search for extraterrestrial intelligence, says UC Santa Barbara physicist Philip Lubin - See more at: http://www.news.ucsb.edu/2016/016805/we-ll-leave-li May 17th, 2016

Smithsonian Science Education Center and National Space Society Team Up for Next-Generation Space Education Program "Enterprise In Space" May 11th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic