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WPI-I2CNER セミナー、九州大学超顕微解析研究センター、ナノテクノロジー・ネット
ワーク「超顕微解析支援」、九州大学超顕微科学リサーチコア共催
第 200 回ＨＶＥＭ研究会
平成 26 年 8 月 25 日
WPI-I2CNER セミナーとの共催で以下の研究会を開催いたします。フランス CNRS の
Xavier Sauvage 博士より、透過電子顕微鏡とアトムプローブを用いた超微細粒金属材料
の微細構造解析に関する話題をご提供いただきます。皆様、奮ってご参加ください。
日時：平成 26 年 9 月 12 日（金），14:00 から
会場：九州大学伊都キャンパス I2CNER ホール
Controlling nanostructures and phase transformations in
ultra fine grained materials processed by severe plastic
deformation for energy applications
Dr. Xavier Sauvage
Research Scientist
CNRS (National Center for Scientific Research), France
Nanostructuring metallic alloys appear as a promising route to achieve high strength and low weight
materials or materials with unique combination of high strength and high electrical conductivity for
low carbon emission in the automotive industry. This presentation reports about the achievement of
such unique structures in aluminium alloys processed by severe plastic deformation. In such systems,
grain size refinement mechanisms are controlled both by the creation of
crystalline defects (especially dislocations) and dynamic recovery processes. In this presentation, it
is proposed to discuss about the influence of alloying elements considering their interaction with such
defects. Various aluminium alloys (AlMg, AlZn, AlCu) processed by severe plastic deformation under
different conditions have been investigated. Beside the classical influence of
the processing temperature and of the solute content on the final grain size, analytical microscopy data
(Transmission Electron Microscopy and Atom Probe Tomography) revealed in some specific
cases deformation induced solute redistribution like grain boundary segregations, clustering or
precipitation. It will be shown that such features can dramatically influence the properties and that
they are promoted first by the enhanced atomic mobility resulting from deformation induced
defects (especially vacancies) and second by “non-equilibrium” boundaries with extrinsic dislocation
arrays. As a conclusion, some possible routes to optimize the combination of
processing parameters and alloy compositions will be proposed to achieve enhanced combination of
properties for future applications in low weight applications of the automotive industry.
********************************************************************* 交通手段や研究会についてのお問い合わせは、下記の連絡先にお願いいたします。
ＨＶＥＭ研究会世話人：安田和弘、波多聰、成田一人
連絡先：堀田善治（九州大学大学院工学研究院材料工学部門）
Tel: 092-802-2958 E-mail: [email protected]
International Institute for Carbon-Neutral Energy Research
Kyushu University
Title Controlling nanostructures and phase transformations
in ultra fine grained materials processed by severe plastic
deformation for energy applications
Speaker Dr. Xavier Sauvage
Research Scientist
CNRS (National Center for Scientific Research)
France
Date & Time
Place
Friday, September 12, 2014 2:00 p.m.
I2CNER Hall, Ito campus, Kyushu University
Abstract
Nanostructuring metallic alloys appears as a promising route to achieve high strength and low weight materials or materials
with unique combination of high strength and high electrical conductivity for low carbon emission in the automotive
industry. This presentation reports about the achievement of such unique structures in aluminium alloys processed by severe
plastic deformation. In such systems, grain size refinement mechanisms are controlled both by the creation of crystalline
defects (especially dislocations) and dynamic recovery processes. In this presentation, it is proposed to discuss about the
influence of alloying elements considering their interaction with such defects. These atomic scale mechanisms were
investigated by analytical microscopy. After a short introduction summarizing the complimentarily application of probe
corrected TEM and Atom Probe Tomography (APT), various examples of ultrafine grained alloys will be presented. Beside
the classical influence of the processing temperature and of the solute content on the final grain size, we will focus on
specific cases of deformation induced solute redistribution like grain boundary segregations, clustering or nanoscale
precipitation. It will be shown that such features can dramatically influence the properties and that they are promoted first
by the enhanced atomic mobility resulting from deformation induced defects (especially vacancies) and second by
“non-equilibrium” boundaries with extrinsic dislocation arrays. As a conclusion, some possible routes to optimize the
combination of processing parameters and alloy compositions will be proposed to achieve enhanced combination of
properties for future applications in low weight applications of the automotive industry.
About the Speaker
Dr. Xavier Sauvage made his PhD on Atom Probe Tomography (APT) investigation of phase transformations in nanoscaled
composites processed by severe plastic deformation. After a short stay at the Max Planck Institut in Stuttgart, he was hired
in 2002 by the CNRS to lead some research on nanostructured materials and severe plastic deformation at the University of
Rouen, France. Using APT in combination with transmission electron microscopy, he investigates deformation induced
atomic transport, interdiffusion and phase transformations especially in nanostructures processed by severe plastic
deformation.
Host: Professor Zenji Horita
Co-hosted: The Ultramicroscopy Research Center
For registration, please visit our website:
http://i2cner.kyushu-u.ac.jp/
CONTACT：Research Support and International Affairs Division
International Institute for Carbon-Neutral Energy Research
TEL:092-802-6934 email:[email protected]