Nanotechnology Now







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

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

Imaging

FEI Technology Award of the German Neuroscience Society Goes to Benjamin Judkewitz of the University of Berlin: Bi-annual award honors excellence in brain research during the German Neuroscience Society’s Annual Meeting, held 18-21 March 2015 March 26th, 2015

Square ice filling for a graphene sandwich March 26th, 2015

Renishaw reports on the use of Raman spectroscopy at CNRS Orléans to study materials under extreme conditions March 25th, 2015

Nanorobotic agents open the blood-brain barrier, offering hope for new brain treatments March 25th, 2015

Discoveries

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Materials/Metamaterials

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

Chemists make new silicon-based nanomaterials March 27th, 2015

UT Dallas engineers twist nanofibers to create structures tougher than bulletproof vests March 27th, 2015

Using magnetic fields to understand high-temperature superconductivity: Los Alamos explores experimental path to potential 'next theory of superconductivity' March 27th, 2015

Announcements

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

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

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

Novel nanoparticle therapy promotes wound healing March 27th, 2015

Tools

LAMDAMAP 2015 hosted by the University March 26th, 2015

FEI Technology Award of the German Neuroscience Society Goes to Benjamin Judkewitz of the University of Berlin: Bi-annual award honors excellence in brain research during the German Neuroscience Society’s Annual Meeting, held 18-21 March 2015 March 26th, 2015

Square ice filling for a graphene sandwich March 26th, 2015

Nanorobotic agents open the blood-brain barrier, offering hope for new brain treatments March 25th, 2015

Automotive/Transportation

Clean energy future: New cheap and efficient electrode for splitting water March 18th, 2015

Imperfect graphene opens door to better fuel cells: Membrane could lead to fast-charging batteries for transportation March 18th, 2015

Researchers synthesize new thin-film material for use in fuel cells: Article in the journal APL Materials shows how to grow Bi2Pt2O7 pyrochlore, potentially a more effective cathode for future fuel cells March 10th, 2015

Glass coating improves battery performance: To improve lithium-sulfur batteries, researchers added glass cage-like coating and graphene oxide March 2nd, 2015

Aerospace/Space

Iranian Researchers Present Model to Determine Dynamic Behavior of Nanostructures March 24th, 2015

Engineers create chameleon-like artificial 'skin' that shifts color on demand March 12th, 2015

Anousheh Ansari Wins the National Space Society's Space Pioneer Award for "Service to the Space Community" March 5th, 2015

Launch of the Alliance for Space Development March 1st, 2015

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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE