Structural Nanomaterials

Dr. Shashank Shekhar,Department of Materials Science and Engineering

During high rate severe plastic deformation (HRSPD), strain and strain-rate are not the only external factors that determine microstructural transformations in materials, temperature-rise due to heat generation from deformation processes, also plays an important role. Temperature may influence the microstructure directly by controlling grain growth kinetics and it may also have an indirect effect through the interactive effect on material behavior, which in turn, influences strain and strain-rate parameters. This complex thermomechanics of HRSPD can lead to myriad of microstructure and consequently, material properties and phenomenon. Encapsulating the process-structure linkages under these conditions is central to controlling process outcomes. Our research utilizes in-situ characterization of deformation in Large Strain Machining across a swathe of directly quantified thermomechanical conditions, in conjunction with various mechanicstic models, to predict the microstructural evolution as a function of deformation parameters (strain, strain-rate and temperature). The overaching aim of this research is to develop a model which can be used as a design tool to predict not only the microstructural properties, but also the mechanical and functional properties, based on the design parameters that were used.

Keywords: Severe Plastic Deformation, Digital Imaging Correlation, Large Strain Machining, Microstructural Evolution