Title: Advanced STEM Characterization of Solute Clusters, Precipitates and Solute Segregation in Light Alloys
Speaker: Prof. Jian-Feng Nie
Date/Time: 2023.11.28 10:00-11:30
Location: Yiucheng Lecture Hall (500), Xu Zuyao Building
Inviter: Prof. YUAN Guangyin
Biography
Employment History
Professor (2009–); Reader (2004 – 2008); Senior Lecturer (2000 – 2003); Senior Logan Research Fellow (1999 – 2000); Logan Research Fellow (1997 – 1999); Research Fellow (1995 – 1997); Department of Materials Science and Engineering, Monash University
Postdoctoral Research Fellow (1994 – 1995)
CSIRO Division of Materials Science & Technology
Postdoctoral Research Fellow (1993 – 1994)
Department of Mining and Metallurgy, The University of Queensland
Professional Memberships
· Member, Materials Australia (1996–)
· Member, The Minerals and Materials Society (TMS), USA (1998–)
Research Interests
· Advanced design and characterisation of light alloys
· Bioresorbable metals for implant devices
· Applications of electron microscopy and diffraction
· Structure-property relationships in advanced metallic materials
· Deformation and strengthening in hexagonal metals
· Crystallography of phase transformation in solids
Professional Services and Distinctions
· Editor, Metallurgical and Materials Transactions, TMS–ASM International (2013–)
· Member of Board of Governors, Acta Materialia Inc. (2023–)
· Chairman, National Events Committee, Materials Australia (2001–)
· TMS Extraction and Processing Division Technology Award, TMS (2018)
· AIME Champion H. Mathewson Medal Award, TMS (2015)
· Chair (2004–2006), Phase Transformations Committee, TMS–ASM International, USA
Publications
Book and Book Chapters
1. I.J. Polmear, D. StJohn, J.F. Nie and M. Qian, Light Alloys: Metallurgy of the Light Metals, 5th Edition (525 pages), Elsevier, 2017.
2. J.F. Nie, “Physical Metallurgy of Light Alloys”, Chapter 20, Physical Metallurgy, 5th Edition, edited by D. Laughlin and K. Hono, Elsevier B.V., pp. 2009-2156, 2014 (invited).
3. J.F. Nie, “Alloys: Magnesium”, Encyclopedia of Condensed Matter Physics, 2nd edition, Elsevier B.V., 2023 (invited).
Papers
1. J.F. Nie, K.S. Shin and Z.R. Zeng, “Microstructure, Deformation and Property of Wrought Magnesium Alloys”, Metall. Mater. Trans. A, Vol. 51, pp. 6045-6109, 2020 (invited review for the 50th Anniversary of Metall. Mater. Trans.).
2. J.F. Nie, N. Wilson, Y.M. Zhu and Z. Xu, “Origin of Ordered Solute Clustering and Assembling in Magnesium Alloys”, Acta Mater., Vol. 106, pp. 260-272, 2016.
3. J.F. Nie, Y.M. Zhu, J.Z. Liu and X.Y. Fang, “Periodic Segregation of Solute Atoms in Fully Coherent Twin Boundaries”, Science, Vol. 340, pp. 957-960, 2013.
4. J.F. Nie, “Precipitation and Hardening in Magnesium Alloys”, Metall. Mater. Trans. A, Vol. 43, pp. 3891-3939, 2012 (invited review article).
5. S.R. Agnew and J.F. Nie, “Preface to the Viewpoint Set on: The Current State of Magnesium Alloy Science and Technology”, Scripta Mater., Vol. 63, pp. 671-3, 2010 (invited co-editor).
6. J.F. Nie, K. Oh-ishi, X. Gao and K. Hono, “Solute Segregation and Precipitation in a Creep-Resistant Mg–Gd–Zn Alloy”, Acta Mater., Vol. 56, pp. 6061-76, 2008.
7. J.F. Nie and B.C. Muddle, “Strengthening of an Al-Cu-Sn Alloy by Deformation-Resistant Precipitate Plates”, Acta Mater., Vol. 56, pp. 3490-501, 2008.
8. J.F. Nie, “Orientation Relationship, Shape Change and Their Traces in Electron Diffraction Patterns and High-Resolution Transmission Electron Microscopy Images”, Acta Mater., Vol. 56, pp. 3169-76, 2008.
9. J.F. Nie, “Preface to Viewpoint Sets on Phase Transformations and Deformation in Magnesium Alloys”, Scripta Mater., Vol. 48, pp. 981-4, 2003 (invited editor).
J.F. Nie, “Effects of Precipitate Shape and Orientation on Dispersion Strengthening in Magnesium Alloys”, Scripta Mater., Vol. 48, pp. 1009-15, 2003 (invited viewpoint paper).
Abstract
Solute clustering, precipitation and solute segregation often occur in light alloys of magnesium, aluminium and titanium, and their occurrence can strongly affect microstructure evolution and deformation behaviour of the alloys. Solute clusters may provide stronger strengthening effects than individual solute atoms and therefore have stronger influence on plastic deformation, in addition to their role in precipitate nucleation. Solute segregation can influence thermodynamic and kinetic features of an interface boundary. While such phenomena have been known for a long time, they are still not well understood at the atomistic level, and a key reason for this is the lack of atomic-scale experimental observations on the precise distribution of solute atoms in the clusters, nano-scale precipitates and the segregation. It is for this reason that the precise roles of micro-alloying elements in microstructure evolution remain speculative. Advances in aberration-corrected scanning transmission electron microscopy (STEM) in the past 20 years provide opportunities for detecting segregated solute atoms and solute clusters at the atomic scale and to reveal the precipitate formation mechanisms when these techniques are combined with atomic-scale computations. This talk will provide an overview of some of our recent studies made by the STEM imaging and mapping techniques on solute clustering, precipitation and solute segregation in selected alloys of magnesium, aluminium and titanium