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    • Modeling serrated flow of SS 316L under dynamic strain aging effect

      SIDDHARTHA PATRA SANKAR DHAR SANJIB KUMAR ACHARYYA

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      The serrated behavior of the stress-strain curves also known as PLC effect due to dynamic strain aging of SS 316L is investigated here from room temperature to 550°C. Tensile tests were conducted for strain rates 10-5-10-2/s. Serrations of type D, type A and type A?B were observed at different loading conditions. Amaterial model was fitted to the experimental data to simulate the serrated flow in the stress strain diagrams. For this an approach similar to a previous study done with an Al-Mg alloy was followed. However, few changes in the analysis steps were performed to accommodate temperature dependency, a feature not addressed in the earlier work. In addition, the fitment technique was improvised so that the material model could be fit through a substantially smaller set of experimental data, thus improving the speed of the fitting process. Finally, comparisons were done between the experimental data and the results from the simulations. Critical strains from the simulations were found to be of the same order of magnitude of the experimental critical strains and theserrations could also be found in the simulated stress-strain diagrams similar in some aspects to the experimental serrations.

    • Bio-sensing application of chalcogenide thin film in a graphene-based surface plasmon resonance (SPR) sensor

      SINGH TAMANG JITENDRA SANKAR DHAR RUDRA KUMAR BHOI AKASH KUMAR SINGH ARUN CHATTERJEE SOMENATH

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      Chalcogenide Glasses are of recent interest in the field of chemical and bio-sensing applications. These are considered either in stored memory devices or in optical domain. The involvement of such material in the bio-sensing application for the development of SPR (Surface Plasmon Resonance) Sensors is very essentialand thus, has been considered in this manuscript. In a Kretschmann SPR configuration, a thin-film layer of such Chalcogenide material has been incorporated which is further accompanied with a Graphene layer. The opticalproperties of both the materials viz. chalcogenide and graphene have been portrayed and presented in this paper by taking the assistance of MATLAB environment and Characteristic Transfer Matrix (CTM) Method.

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