Research Focus

Coatings are used to protect metal surfaces from friction, wear, and thermal stress. Zirconium and zirconium-based alloys are examples of coating materials used in nuclear and electronic applications. We are interested in understanding metal-metal interactions, which is essential in the design and fabrication of robust and highly efficient advanced materials for specialized applications. Systems under investigation include Zr-rich alloys such as Zr-Nb, Zr-Hf, Zr-Sn, Zr-Al and other related metal-metal systems. Previously, we studied Ag/Au metal-metal interaction.

Our approach involves density functional theory in the characterization of metal-metal interactions. We use plane-wave DFT calculations on zirconium unit and supercells (2x2x2) using the Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA) as implemented in Quantum Espresso. Parameters obtained include reversible work of adhesion to characterize the stability/cleavage properties at the metal-metal interface and the density of states computed is then employed to explain the nature of adhesion at the interfacial region. Computational tensile tests in the rigid grain shift (RGS) framework are performed and a generalized universal binding energy relation (UBER) is used to describe the energy-displacement data. Elastic constants are measured using the strain-stress relationship method as implemented in ElaStic2020.3. Based on our experience, we have created training modules for metal-metal characterization using DFT.

Currently, our group is looking at phonon band structures for Zr-M systems to determine the overall phonon contribution to thermal transport (thermal boundary conductance; thermal conductivities) at the metal-metal interface of Zr-M systems, including the effect of alloying on the characteristic phonon band structure of Zr-M. Possible applications will be in coatings/claddings, metal-surface mediated transformations, orthopedic/medical devices and optoelectronic applications.

Our group is also active in the development of implementation policies and analytical tools relevant to CBRN Risk Mitigation, wherein we coordinate with government agencies, chemical/pharmaceutical industries, and other stakeholders (regional and international organisations). One upcoming project is in the development of new technologies and robust analytical protocols in CBRN risk mitigation.