Our virtues and our failures are inseparable, like force and matter. When they separate, man is no more

Over the span of my academic career, my research was focused on the experimental and computational investigation of the deformation mechanisms and constitutive modeling of materials when subjected to wide range of loading rates and temperatures. I studied different types of materials such as metals, polymers, glass, alloys, and nano-cellular solids. My past research experience shows my extensive efforts in acquiring the knowledge, experience, and funding to achieve my research goals. Below is a summary of my research experience at each step of my journey so far.

My work at ORNL  is directed towards developing numerical algorithms and codes to perform large scale simulations and generate physics based predictive models to guide the development of  novel chemical and material processes for additive manufacturing, material synthesis, mitigating gas emissions, dehydrogenation, separation processes, and production of platform olefins applications. Such large scale projects require:

• Collaborating with a multi-disciplinary research environment consisting of computational scientists, experimentalists, engineers, and physicists.
• Developing parallel large-scale computationally efficient numerical methods and discretization schemes algorithms using C++, message passing (MPI), and programming models (e.g., CUDA, OpenMP, Kokkos) for multicore and heterogeneous architectures (e.g.,  graphical processing units (GPUs)).
• Participating in the design and architecture of integrated, multi-scale, coupled-physics computer codes, design and implementation of scalable numerical methods, uncertainty quantification, verification and validation, and software quality processes. 

During my postdoctoral fellowships at University of Missouri (MU), I was leading the efforts in two major multi-million-dollar projects to carry out the portions corresponding to material characterization and multiscale numerical modeling of different materials and structural systems. This includes the development and design of blast resistant curtain wall and anchorage system through field testing, material characterization, and computational modeling of laminated glass panels along with their polymer interlayers, the aluminum framing and anchorage components, and the steel connections and bolts. Additionally, I worked on an interdisciplinary multiscale investigation of the shock response of metallic foams to probe their energy dissipation as well as their deformation mechanism.

During my PhD and second master's degree, my research work was designed to work on large-scale atomistic simulations to investigate the effect of size, strain rate, and temperature to probe the elastic response, plastic response, and deformation mechanisms in metallic foams using Molecular Dynamics. This work explored the full range of the material response, focusing on the modifications to strain hardening and densification under compression and on the ductility and failing mechanisms under tension. Additionally, a series of scaling laws and dislocation based constitutive formulations that account for the effect of free surfaces, size, porosity, strain rate, and temperature were then developed to predict material properties and the plastic flow within. Finally, the atomistic simulations as well as the proposed constitutive models are used to modify a continuum dislocation-based model, providing an atomistic-continuum constitutive multiscale connection for metallic foams.

During my first master’s degree studies, I worked on investigating the thermo-mechanical behavior of C45 steel which is widely used in the oil and gas offshore construction industry and the manufacturing of heavy machinery. After careful experimental investigation, data are utilized to modify the existing Johnson-Cook constitutive model to include an energy-based damage parameter that captures the softening and necking mechanisms in the material. The primary goal was to introduce a systematic understanding of the thermo-mechanical ductile failure that occurs due to accumulation of micro-cracks and voids along with plastic deformation in C45 steel since it is commonly utilized in environments of high temperatures and strain rates. The coupling effect of damage and plasticity is incorporated into a commercial Finite Element (FE) software (ABAQUS) to develop a robust model that can accurately simulate different structural responses of this material.