BOOK OF ABSTRACTS ISMANAM-2019 26th International Symposium on Metastable, Amorphous and Nanostructured Materials July 8-12, 2019|Chennai, India Organized by Dept. of Metallurgical and Materials Engineering Indian Institute of Technology Madras https://mme.iitm.ac.in/ismanam2019 A NOTE FROM THE ORGANISERS Dear friends, The organizing team of ISMANAM-2019 is immensely grateful to you for associating with the 26th International Symposium on Metastable, Amorphous and Nanostructured Materials (ISMANAM- 2019) to be held during on July 8-12, 2019, organized by the Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, India. ISMANAM is a prestigious global event ever since its inception in 1993 (Paris). The subsequent symposia have been held in Grenoble (1994), Quebec (1995), Rome (1996), Sitges (1997), Wollongong (1998), Dresden (1999), Oxford (2000), Ann Arbor (2001), Seoul (2002), Foz do Iguaçu (2003), Sendai (2004), Paris (2005), Warsaw (2006), Corfu Island (2007), Buenos Aires (2008), Beijing (2009), Zürich (2010), Gijón (2011), Moscow (2012), Turin (2013), Cancún (2014), Paris (2015), Nara (2016), San Sebastian (2017) and Rome (2018). ISMANAM-2019 (Chennai) is the 26th conference in this series, held in India for the first time. The aim of the conference was to provide a suitable platform for the exchange of ideas in the areas of metastable, nano and amorphous materials. The symposium not only helped the scientific community to stay updated with the latest developments, but also enabled discussion on the key scientific challenges in the field. ISMANAM 2019 had 422 participants from 27 different countries. The technical program consisted of a Plenary Session on each day with two plenary speakers followed by 4 parallel sessions. A total of 48 parallel technical sessions were organised over the period of 5 days, in addition to the plenary sessions. These technical sessions had keynote, invited, contributory papers presented by active researchers in the field. A total of 245 oral presentations were made in all the above sessions. In addition, about 112 posters were presented by the PhD students in 9 different poster sessions. The conference covered a wide range of topics including amorphous, nano structured and high entropy materials, in bulk, porous, thin films and coating forms. The presentations included structural and functional properties of these materials, various processing routes, atomistic modelling and structure of nano and amorphous materials, to name a few. The posters were evaluated by the experts in the field and one best poster award was given in each session. The poster awards included a Certificate and gift vouchers for books worthy of 100 Euro and 60 GBP from Springer and Royal Society of Chemistry, respectively. We are thankful to all the Plenary, Keynote and Invited speakers and other participants who have spared their precious time for the sake of the conference and making it a grand success. We are grateful to the overseas friends, who have taken the pain to travel long distances to be a part of ISMANAM-2019. We are also indebted to the Session Chairs and Poster Judges for helping us in the conference. We are grateful to all the sponsors and advertisers without whose support this conference would not have become successful. We will be failing in our duty if we do not acknowledge and appreciate the support from all the members of the local organizing committee and the volunteers who have worked hard, day and night, towards the success of the conference. We sincerely hope that you had enjoyed the conference and had a fruitful exchange of ideas. N.K. Mukhopadhyay and B.S. Murty Co-Chairs, ISMANAM-2019 1 ORAL SESSION ABSTRACTS 2 DAY-1 8th July 2019 3 PL-1 The inverse problem of designing for grain boundary segregation in nanocrystalline alloys Christopher A. Schuh Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, USA E-mail: [email protected] While grain boundary (GB) segregation is a classical topic in physical and mechanical metallurgy, most of our knowledge of it has been cataloged for systems in which it is undesirable, e.g., in terms of chemical attack or embrittlement. By contrast, in nanocrystalline alloys the beneficial use of GB segregation has become the primary approach to stabilize nanostructure against coarsening, and a variety of new commercial products owe their viability to beneficial GB segregation. This talk will review the science of GB segregation, emphasizing the inverse problem of intentionally designing it into nanocrystalline alloys. The large gap in fundamental thermodynamic data for GB segregation in arbitrary binary alloy pairs presents substantial opportunities for modeling and computation. We review simple Miedema-type models as well as more accurate atomistic methods as means of developing catalogs of viable alloy pairs. Whereas the simplest models consider some ‘average’ grain boundary site energy and can provide great insights and successful alloy designs, greater richness and more alloying possibilities emerge if a more realistic spectrum of sites is considered in the design process. Finally, the talk will point to future opportunities in the development of a fully integrated nanocrystalline alloy design effort, incorporating, e.g., ternary effects and processing pathway predictions amenable to the development of a stable nanocrystalline structure. PL-2 Strain hardening in metallic glasses? A. L. Greer Department of Materials Science & Metallurgy, University of Cambridge, UK E-mail: [email protected] Strain hardening is characteristic of the plastic deformation of polycrystalline metals. This hardening is desirable for engineering materials as it promotes uniform deformation, imparting ductility, and hindering catastrophic mechanical failure. In metallic glasses (MGs), in contrast, it is well accepted that there is strain-softening. In room-temperature deformation in particular, this softening leads to sharp localization of flow into thin shear bands. Shear bands are undesirable, leading to premature mechanical failure, unsightly surface markings on deformation, and acting as continuing planes of weakness in deformed MGs. Indeed, shear banding is the principal impediment to wider acceptance of MGs in engineering applications. There has therefore been interest in achieving strain hardening in MGs, thereby impeding shear banding, in particular achieving more uniform flow through a higher population of shear bands with (for a given overall strain) a smaller shear offset on each one. Progress has been made by introducing various heterogeneities into a MG matrix, including prior shear bands. It would be of still greater interest, however, to achieve similar effects in a monolithic uniform MG. The literature contains several reports of what is usually termed ‘apparent’ strain hardening. These are reviewed in detail, with consideration of the possible origins of the observed hardening, which include sample-size effects and constraint of flow under triaxial loading. The prospects are considered for achieving strain hardening in bulk MGs under simple uniaxial loading, i.e. similar to that observed for polycrystalline metals (though necessarily of different origin). 4 KN-1 Multicomponent and high-entropy alloys Brian Cantor University of Bradford, West Yorkshire, UK E-mail: [email protected] Conventional strategy for developing metallurgical alloys is to select the main component based on a primary property requirement, and to use alloying additions to confer secondary properties. This strategy has led to the development of many successful alloys based on a single main component with a mix of different alloying additions to provide a balance of required in- service properties. Typical examples include high temperature Ni superalloys, wrought Al alloys and corrosion resistant stainless steels. However, conventional alloy development strategy leads to an enormous amount of knowledge about alloys based on one component, but little or no knowledge about alloys containing several main components in approximately equal proportions. Theories for the occurrence, structure and properties of crystalline phases are similarly restricted to alloys based on one or two main components. Information and understanding is highly developed about alloys close to the corners and edges of a multicomponent phase diagram, with much less known about alloys in the centre of the diagram. This talk describes a range of other multicomponent alloying strategies, gives a number of examples of high-entropy and other multicomponent alloys and discusses their structure and properties. IN-1 Tailoring microstructure and mechanical properties of multiphase high entropy alloys P. P. Bhattacharjee Indian Institute of Technology Hyderabad, Kandi, India E-mail: [email protected] High entropy alloys (HEAs) have originally been developed following the novel alloy design strategy of mixing five or more elements in equiatomic or near equiatomic concentrations. Despite their concentrated alloy chemistry, the HEAs may show simple crystal structures (such as FCC, BCC or FCC+BCC) owing to their increased configurational entropy. More recently, the definition of HEAs has been expanded to include non-equiatomic multiphase alloys, which has opened up the massive composition space for developing alloys with novel compositions and properties. Nevertheless, the microstructures of the HEAs need to be tuned for realizing superior mechanical