Recent News

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21st February 2018 (Wednesday 2.30pm)

New Twinning Route in FCC metals and the Inter-grain plasticity in nanocrystalline materials Revealed through Precise Atomic Resolution Mechanical Microscopy

Special Seminar: Wednesday 21st February 2018 Hume-Rothery Lecture Theatre 2.30pm
Prof. Xiaodong Han / Institute of Microstructure and Property of Advanced Materials / Beijing University of Technology

We developed the precise atomic resolution mechanical microscopy (PRAMM) for investigation of the strain-induced atomic resolution dynamics of materials’ mechanical properties and related scientific problems. With simultaneous precise atomic resolution imaging with strains applied on structural and functional materials samples, the strain induced atomic (clusters, or/and arrays) evolution process of these structural, physical and chemical processes can be in situ monitored. We show several examples of the atomic scale precise details including the deformation dynamic details of Ni, Pt, Au and Cu. Ultra-large strain elasticity, size-dependent elasto-plastic transitions and the unusual plasticity behaviors of metals at different scales and sizes were revealed and demonstrated. Some novel dislocation and twinning nucleation and propagation processes at atomic scale were directly captured and visualized. For example, the cross-over plasticity mechanisms from partial dislocation to full dislocation and twins were discovered in deformation of single crystalline Cu samples. A long standing puzzle and uncertainties of grain rotation in ultra-small nano-sized polycrystalline materials (grain size less than 8nm) was demonstrated through PRAMM. It was also uncovered that the dislocation climb takes care of the grain rotation behaviors in small grain systems. The atomistic mechanisms of plasticity and its dynamics of on interfaces, twinning and grain boundaries have opportunities to be directly clarified. These results shed lights in understanding the important mechanical behaviors and the related dislocation activities of the structural materials and useful for designing new structural materials with strength and ductility. With Cs-corrected imaging and probing abilities, the opportunities for developing advanced structural materials with the assistance of PRAMM will mark a new content of microscopy and light metals.

 

Reference:

[1] NANO LETTERS, 9, 2471 (2009), NANO LETTERS, 11, 3151 (2011), NANO LETTERS, 12, 4045 (2011)

[2] NATURE COMMUNICATIONS, 1, 24, DOI: 10.1038/ncomms1021, 2010

[3] NATURE COMMUNICATIONS, 3, 609, DOI: 10.1038/ncomms1619, 2012

[4] NATURE COMMUNICATIONS, 4, 2413, DOI: 10.1038/ncomms3413, 2013

[5] NATURE COMMUNICATIONS, 5, 4402, DOI: 10.1038/ncomms5402, 2014

[6] NATURE COMMUNICATIONS, 8, 2142, DOI: 10.1038/s41467-017-02393-4, 2017

[7] PHYS. REV. LETTS., 105, 135501 (2010)

[8] ACAT MATER., 59, 6511 (2011), ACTA MATER. 61, 4689 (2013), SCRIPTA MATER., 134, 95 (2017)

[9] NANO LETTERS, 12, 4595 (2012); NANO LETTERS DOI: 10.1021/acs.nanolett.7b01416 (2017)

 

Xiaodong Han currently works as a professor at Institute of Microstructure and Property of Advanced Materials of Beijing University of Technology. His research interest mainly focuses on developing novel electron microscopy tools and instruments for atomic scale and multi-scale in situ experiments on structural and functional materials. His interests include high strength yet ductile structural materials, energy related materials and physics and catalysis materials, atomic scale understanding solid-solid, liquid-solid and gas-solid reactions etc. He published more 160 papers at international recognized peer-reviewed journals such as Science, Nature Materials, Nature, Communications, Nano Letters, Physical Review Letters and Acta Mater etc.. Currently, he serves as the President of Chinese Electron Microscopy Society.

Li ion batteries

24th January 2018

Oxford to have key role in multi-million pound energy storage research

Oxford University is to be a key player in an extensive new activity supporting the development of next-generation batteries, enabled by £42 million funding provided by the independent national battery research facility, The Faraday Institution.  The four initial projects announced are focused on solid-state electrodes, battery modelling, degradation, and recycling. 

Professor Peter Bruce, FRS, FRSE, Wolfson Professor of Materials in Oxford’s Department of Materials, will lead the work on developing solid-state metal-anode batteries. The ambition of this project is to demonstrate the feasibility of a solid state battery with performance superior to Li-ion in Electric Vehicle applications. 

 

Prof Lapo Bogani

19th December 2017

ERC consolidator grant for Prof Lapo Bogani

Congratulations to Prof Lapo Bogani on being awarded a prestigious ERC consolidator 5 year grant supporting his research on "Molecular Magnetic Graphene Nanoribbons" as part of the EU's Horizon 2020 programme.  Eight of the 60 grants awarded to UK institutions were given to Oxford University researchers. 

Prof Peter Bruce

28th November 2017

Peter Bruce among world’s most influential scientific minds – three years in a row.

Congratulations to Prof Peter Bruce for being named as a Thomson Reuters Highly Cited Researcher for the third year in a row. Professor Peter Bruce FRS, Wolfson Chair of Materials and an expert in materials for energy storage, is one of the most highly cited researchers in chemistry. Read more about Professor Peter Bruce's research on the group website.

Dr Roger Booker

10th November 2017

Dr Roger Booker (1927 – 2017)

It is with great sadness that the department announces the death of our respected and eminent colleague. Roger joined the department in 1966 and pursued world leading research into the structure and properties of defects in semiconductors and their effect on electronic devices. Roger formally retired from the department in the early 1990’s but then continued to provide research student supervision for several years.

Lithium Battery

20th October 2017

£65 million battery technology research institute

Business Secretary Greg Clark has announced the consortium of UK universities that will form the Faraday Battery Institute, a new £65 million research institute responsible for building the UK’s status as a global leader in battery research and technology.

The University of Oxford is one of the seven partners in the institute. The Oxford component will be headed up by Professor Peter Bruce and colleagues in the Department of Materials.

David Pettifor 1945-2017

20th October 2017

Professor David Pettifor CBE FRS (1945 - 2017)

It is with great sadness that the department announces the death of one of our most respected and eminent colleagues. David joined the department in 1992 as the Isaac Wolfson Professor of Metallurgy and established the Materials Modelling Laboratory. The MML became a national and international centre for research into the theory of metals and other materials, and continues to this day to fulfil the founding vision of understanding and designing materials from the sub-atomic to engineering scale. David formally retired from the department in 2011 but continued to provide supervision, guidance and irreplaceable wisdom to many early career research scientists and colleagues.

pdf Read David’s obituary by Professor Adrian Sutton FRS (Imperial College London), which appeared in shortened form in The Times on 5 January 2018.

19th October 2017

David Armstrong appointed Associate Professor

David Armstrong, currently a RAEng Fellow in the department, has been appointed to the new Associate Professorship in Materials, jointly with Corpus Christi College from 1st October 2017. Professor Armstrong is an expert in the micromechanical properties of materials, with a focus on materials for the most demanding environments, including Ni superalloys, steels, refractory alloys and ceramic-ceramic composites.

Nanomaterials Film

18th October 2017

Public Engagement in Science

Fresh from appearing in this year’s Hay Festival as part of The Royal Society's The Next Big Thing public engagement with science, Professor Nicole Grobert has made a film explaining nanomaterials.

Prof Feliciano Giustino

15th September 2017

Prof Giustino elected Upson Visiting Professor at Cornell

Professor Feliciano Giustino has been elected the Mary Shepard B. Upson Visiting Professor in Engineering at Cornell University for Fall 2017 through Spring 2018. Prof. Giustino will be visiting the Department of Materials Science and Engineering at Cornell for collaborative work with faculty and students, and will deliver a Summer school on ab-initio computational materials modelling within PARADIM, the NSF Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials led by Prof. Darrell Schlom.