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Education
Ph.D. Thesis on "Interaction of Hydrogen isotopes with radiation effects in metals”
Positions Held Professor, Homi Bhaba National Institute and Head, IB&CSS, MPD, MSG, IGCAR, Kalpakkam
Dr. B. K. Panigrahi joined Materials Science Division in August, 1982 after graduating from 25thbatch of training school. He is a specialist in the area of analysis, synthesis and modification of materials using ion beams, in particular the study of defects & radiation damage, nano-structured materials and computer simulations. His nature of work include initiating and implementing research programmes and providing research guidance to Ph.D. students. He has more than 125 publications in journals and conferences. Some of the recent research works are highlighted below. Study of defects and radiation damage: He has initiated a strong R&D programme for the study of radiation damage using charged particles from ion accelerators to obtain comprehensive understanding of radiation damage phenomena with particular reference to fast reactor materials. An unique experimental facility for measurement of void swelling at DPA levels of more than 150 dpa using heavy ion beam from 1.7 MV accelerator was set up at MSD, IGCAR. Using these facilities, detailed studies on the temperature and dose dependence of void swelling and the effect of minor alloying elements like Ti ,P on the swelling behavior of of D9 alloy, the material for clad and wrapper in the FBRs have been carried out. To obtain a comprehensive understanding of irradiation behaviour of materials, a programme on theoretical modeling and numerical simulation using multi-scale modeling and insitu experiments for investigating defects has also been conducted. Ab initio calculations based on density functional theory are carried out to understand the formation and stability of complex oxide nanoclusters in model ODS alloys, especially the role of vacancies, produced by mechanical alloying, and role of Y and Ti in the stability and structure of these complex oxide nanoclusters.
Synthesis and characterization of embedded nano-clusters prepared by ion beam synthesis:
Preparation of Ag, Au, Si, Co and Ge nano-clusters embedded in quartz, sapphire and glass matrix by ion implantation, ion beam mixing and irradiation of ion exchanged glass. Characterization by optical absorption, low frequency Raman scattering, X-ray diffraction and TEM. Study of their optical and electrical conductivity properties. For the first time, the growth sequence of Ag nanoclusters in glass matrix, which show remarkable Photoluminescence behaviour, was established. CoPt nano clusters having L10 ordered phase which show magnetic anisotropy, has been synthesized by direct Pt ion irradiation of a Pt/Co bilayer and subsequent beam annealing using Si ions. Formation and optical characterization of epitaxial SiC nanocrystals by high temperature C ion implantation into Si . Study of ion beam mixing and phase formation in thermally immiscible systems:
Synthesis of nanosized granular Fe/Ag and Co/Ag films by ion beam mixing of multilayers and characterization by X-ray reflectivity, TEM, SIMS, CEMS, RBS and GIXRD. For the first time in literature, a complete ion beam mixing in Fe/Ag system was demonstrated. Our investigations provided a clear understanding of ion beam mixing processes in these immiscible systems especially the role of interfaces and interfacial free energy in the mixing process and in the formation of metastable phases, which can have interesting applications in producing nano structured granular systems.
Awards & Fellowships:
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