Materials World Network: Nanoscale studies of fundamental mechanisms of deformation in amorphous materials

Lead Research Organisation: University of Cambridge
Department Name: Materials Science & Metallurgy

Abstract

Conventional metallic alloys can be shaped by forming processes. This ability to undergo 'plastic deformation' is exploited in making components, but is also important in making the materials resistant to cracking. Plastic deformation is facilitated by the crystalline structure of the metals within which planes of atoms can slide over each other mediated by defects called 'dislocations'. The dislocation mechanisms of plastic deformation have been very widely studied and are well understood. In contrast, conventional glasses (amorphous solids) do not have a crystalline structure. While glasses can flow when softened by heating, when they are stressed at room temperature they typically show brittle fracture by cracking. Yet, if cracking is avoided, glasses are strong. There is much current interest in developing glasses into materials with usable strength so that their engineering applications could be increased. A starting point is metals with glassy rather than crystalline structure ('metallic glasses'). These materials they do show some plasticity, but unfortunately their deformation under loading is not uniform. The plastic deformation is instead localised in very thin 'shear bands'. But it has gradually become clear that while deformation is concentrated in the bands, there must be substantial flow of the apparently undeformed material between them. This opens up a whole new field of study of plastic deformation of glassy materials. This project aims to develop a fundamental understanding of the mechanisms of such deformation by comparing different types of glass ranging from metallic glasses to amorphous silicon (in essence comparing the effects of metallic and covalent bonding). The research involves sensitive tests of mechanical properties using techniques such as nanoindentation and deformation of micropillars. Such probes are useful for studying deformation mechanisms and can be used over a wide range of temperature. They form the heart of the UK-based work, which is however just part of an international collaboration with partners in the USA (Johns Hopkins University, Baltimore) and Japan (Tohoku University, Sendai). Work on these other laboratories will focus on high-resolution studies of the structures of the deformed materials and on atomistic modelling based on the concept of 'shear transformation zones'. Overall complementary expertise has been assembled to elucidate the mechanisms of plasticity in the absence of crystalline structure. In this way, there is the prospect of developing glasses of whatever kind with greatly improved mechanical properties, enabling their wider exploitation as engineering materials with outstanding performance.

Planned Impact

New Materials The proposed research is on fundamental mechanisms, so the likely benefits are in the medium-to-long term. Those benefits, however, are potentially large - in effect being to extend to glassy materials the reliability of properties, and the ability to control those properties, that are taken for granted with engineering alloys. Glasses can then become structural engineering materials in the full sense. We expect new materials that are stronger, tougher and more resistant to fatigue. It is important to emphasise that the project builds on some progress already made - for example, metallic glasses are starting to show (with special compositions and processing treatments) combinations of high strength and high toughness that are simply not matched by any conventional engineering material. However, this project is not confined to metallic glasses, but considers glassy materials more generally. Who will benefit? With a family of new materials, the benefits are likely to be distributed widely and difficult to quantify. The most obvious opportunities are for industry. In this regard, it is of interest to note that the oxide glass industry (in which, of course, the UK has a sizable stake) is currently very interested in Usable Glass Strength , see http://www.gmic.org/Strength%20In%20Glass.html In the USA, the Glass Manufacturing Industry Council (GMIC, see above site) is studying the potential impact on society of having glasses with increased strength. They conclude that improving usable glass strength is critical for a vibrant glass industry in the future and that the potential for breakthrough success is high! How will they benefit? Improved materials bring a broad benefit to individuals and institutions in lower-cost devices with improved functionality. They can provide (through their manufacture, or their usage) a competitive edge to UK industry. For likely industrial benefits, we can again look to the preliminary studies of the GMIC (based in the USA, but with an international reach) on the possibilities for stronger glass. They have, for example, held prize competitions around the question: So, what would YOU do with stronger glass? . Among Realistic Applications , the GMIC lists: structural glass, stronger solar panels, thin solar panels, skyscraper agriculture, glass roofs. And under the heading Future applications can change the way we live , the GMIC lists: aeronautics, transportation, buildings, energy storage, light pipes, food and drink containers, telecommunications. Among potential advantages, the GMIC notes that glasses can have a theoretical strength higher than steel with one third the weight, that they can be corrosion proof, with attractive & engineered appearance. The potential for industry is great, with corresponding benefits for the consumer across the range of sectors noted above as well as biomedical. The potential for better exploitation of glassy materials (of all types) in MEMS devices is particularly high. UK industry in advanced materials has much to gain, in the medium-to-long term, from the advent of fully engineered glasses with improved and controlled mechanical properties. Research and Professional Skills: Staff on the project will be trained in state-of-the-art techniques, involving structural characterization, measurement of mechanical properties and atomistic modelling of fundamental mechanisms - an unusually broad range that will equip them well. The analytical skills would be useful not only in many technical (scientific/engineering) areas, but also in finance and administration, the ability to model quantitatively and to analyse mechanisms being particularly important.

Publications

10 25 50
 
Description Metallic glasses are a novel state of matter. They can be very strong, but have their plastic flow at room temperature is not easy to control by the methods developed for conventional crystalline metals. In this project good progress has been made on understanding the initiation processes for plastic flow, and this will lead to better control of glass forming. A key breakthrough has been the discovery of a new way to "rejuvenate" metallic glasses. The glasses when stored for a long time, or when heated undergo relaxation of their structure, often termed "ageing". This brings undesirable changes in properties such as brittleness. Therefore a way of undoing ageing is highly attractive. Our new treatment of thermal cycling can achieve this quite simply. This treatment has now been adopted by several groups around the world. Its beneficial effects have been widely confirmed.
Exploitation Route Increased use of metallic glasses, particularly for small components required high strength, high wear resistance, low friction and the ability to be shaped very precisely.
Sectors Aerospace, Defence and Marine,Energy,Manufacturing, including Industrial Biotechology

URL http://www.nature.com/nature/journal/v524/n7564/full/nature14674.html
 
Description Discussions were held with two companies (Liquidmetal and Super Cool Metal) with a view to exploitation of some of our strategies for property improvement. This engagement now includes a third company (Vacuumschmelze GmbH, Hanau, Germany); we are working with this company to explore the prospects for applying our thermal cycling treatment to improve the processing of soft-magnetic alloys.
First Year Of Impact 2015
Sector Manufacturing, including Industrial Biotechology
Impact Types Economic

 
Description Advanced Grant
Amount € 2,434,092 (EUR)
Funding ID 695487 
Organisation European Research Council (ERC) 
Sector Public
Country European Union (EU)
Start 10/2016 
End 09/2021
 
Description SELECTA 
Organisation Autonomous University of Barcelona (UAB)
Country Spain 
Sector Academic/University 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation Chalmers University of Technology
Country Sweden 
Sector Academic/University 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation Clinical Center of Serbia
Country Serbia 
Sector Hospitals 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation Happy Plating GmbH
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation Leibniz Association
Department Leibniz Institute for Solid State and Materials Research
Country Germany 
Sector Public 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation National Institute of Meteorological Research (INRIM)
Country Italy 
Sector Public 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description SELECTA 
Organisation University of Ioannina
Country Greece 
Sector Academic/University 
PI Contribution Design and mechanical properties of sustainable amorphous, nanocrystalline and metal-ceramic films.
Collaborator Contribution A Marie Curie Innovative Training Network funded by the European Commission under Horizon 2020. Aims to design, fabricate and characterize Smart ELECTrodeposited Alloys for environmentally sustainable applications, from advanced protective coatings to micro/nano-robotic platforms.
Impact One publication so far: "Growth and characterization of in-situ formed Fe-TiN nanocomposite sputter-deposited coatings" S. Thirumalai, Z. H. Barber, J. A. Williams and A. L. Greer, Surface and Coatings Technology 358 (2019) 427?434.
Start Year 2015
 
Description VitriMetTech 
Organisation Marie Sklodowska-Curie Actions
Department Initial Training Networks (ITN)
Country Global 
Sector Charity/Non Profit 
PI Contribution Collaborative research on the mechanical properties of metallic glasses, including the exchange of data.
Collaborator Contribution Collaborative research on the mechanical properties of metallic glasses, including the exchange of data.
Impact Two publications: "Rejuvenation decreases shear band sliding velocity in Pt-based metallic glasses" P. Denis, C. M Meylan, C. Ebner, A. L. Greer, M. Zehetbauer and H.-J. Fecht, Materials Science and Engineering A 684 (2017) 517-523. "Indenter size effect in high-pressure torsion deformed Pd-based metallic glass" P. Denis, G. Ababei, C. M. Meylan, A. L. Greer and H.-J. Fecht, International Journal of Materials Research 109 (2018) 381?385.
Start Year 2013
 
Description WPI-AIMR 
Organisation Tohoku University
Country Japan 
Sector Academic/University 
PI Contribution Collaborative research, including sharing of results, on the mechanical properties of metallic glasses.
Collaborator Contribution Collaborative research, including sharing of results, on the mechanical properties of metallic glasses.
Impact Joint research papers. In addition to those reported in other sections, there are: 1. "Toughness, extrinsic effects and Poisson's ratio of bulk metallic glasses" S. V. Madge, D. V. Louzguine-Luzgin, J. J. Lewandowski and A. L. Greer, Acta Materialia 60 (2012) 4800-4809. 2. "Large compressive plasticity in a La-based glass-crystal composite" S. V. Madge, D. V. Louzguine-Luzgin, A. Inoue and A. L. Greer, Metals 3 (2013) 41-48. (special issue on Amorphous Alloys, edited by H.-J. Fecht). 3. "Crystal growth limitation as a critical factor for formation of Fe-based bulk metallic glasses" D. V. Louzguine-Luzgin, A. I. Bazlov, S.V. Ketov, A. L. Greer and A. Inoue, Acta Materialia 82 (2015) 396?402.
Start Year 2013