Nikhil Chandra Admal

For more information

• Google Scholar
• ResearchGate
• Research webpage

Education

• Ph.D. Aerospace Engineering and Mechanics, University of Minnesota 2014
• M.S. Mathematics, University of Minnesota 2011
• M.S. Aerospace Engineering and Mechanics, University of Minnesota 2010
• B. Tech., M. Tech. (Dual degree) Mechanical Engineering, Indian Institute of Technology Madras 2006

Academic Positions

• Assistant Professor, Department of Mechanical Science and Engineering, Jan 2019 - Present
• Adjunct Assistant Professor, Department of Mechanical Science and Engineering, Aug 2018 - Jan 2019
• Postdoctoral Research Scholar, Materials Science and Engineering, University of California Los Angeles, Sep 2014 - Jan 2019

Major Consulting Activities

• FermiLab, Batavia, Illinois - Design of composite superconducting cable windings of solenoids used to generate magnetic fields in the Mu2e project.

Professional Registrations

• Society for Engineering and Science (SES)
• American Society for Mechanical Engineers (ASME)
• United States Association for Computational Mechanics (USACM)

Resident Instruction

• TAM 210/211 Statics
• TAM 445 Continuum Mechanics
• TAM 574 Advanced Finite Element Method

Research Statement

My primary research interest is in materials modeling and microstructure engineering of new materials for applications in extreme environments. Currently, the focus of my research is on the engineering of refractory materials (tungsten alloys) for improving the efficiency of thermal power plants, fusion reactor materials, materials with superior toughness and thermal stability for use in the aerospace and automobile industries. The overarching goal of my research is to design new materials by exploring the hierarchical structure-property relationships operating at multiple scales.

The research topics described above bring into focus some of the fundamental open questions in mechanics and metallurgy such as the phenomena of recovery, recrystallization and grain growth which are different stages of microstructure evolution occurring at the atomic scale but which manifest themselves in macroscopic properties. Classical continuum models are often insufficient to predict these complex phenomena due their inherent multiscale nature. On the other hand, atomistic models have the potential to predict such phenomena, but often cannot extend into experimentally measurable spatial and temporal scales. Models at the mesoscale, which enable a continuum description of the microstructure, are ideal to model microstructure evolution as they are computationally tractable. The central theme of my research is to formulate truly predictive thermodynamically-consistent mesoscopic models, with material parameters obtained from atomistic simulations. This requires establishing a rigorous link between the hierarchy of models.

Research Interests

• Nanomechanics
• Crystal plasticity
• Grain Boundary Mechanics
• Solid Mechanics and Materials

Selected Articles in Journals

• Shi, M., Admal, N. C., & Tadmor, E. B. (2020). Noise filtering in atomistic stress calculations for crystalline materials. Journal of the Mechanics and Physics of Solids, 144, 104083.
• Po, G., Admal, N.C. & Svendsen, B. Non-local Thermoelasticity Based on Equilibrium Statistical Thermodynamics. J Elast 139, 37–59 (2020).
• N. C. Admal, Javier Segurado, Jaime Marian. "A three-dimensional misorientation axis- and inclination-dependent Kobayashi--Warren--Carter grain boundary model." Journal of the Mechanics and Physics of Solids, 128, 32-53, 2019
• Po, G., Admal, N. C., Lazar, M. "The Green tensor of Mindlin's anisotropic first strain gradient elasticity." Materials Theory, 3(1), 3, 2019
• N. C. Admal, Giacomo Po, Jaime Marian. "A unified framework for polycrystal plasticity with grain boundary evolution." International Journal of Plasticity, 106:1-30, 2018
• Giacomo Po, Markus Lazar, N. C. Admal, Nasr Ghoniem. "A non-singular theory of dislocations in anisotropic crystals." International Journal of Plasticity, 103:1-22, 2018
• N. C. Admal, Giacomo Po, Jaime Marian. "Diffuse-interface polycrystal plasticity: Expressing grain boundaries as geometrically necessary dislocations." Materials Theory, 1(1):6, 2017
• N. C. Admal, J. Marian, Giacomo Po. "The atomistic representation of first strain-gradient elastic tensors." Journal of the Mechanics and Physics of Solids, 99:93-115, 2017
• N. C. Admal, Ellad B Tadmor. "Material fields in atomistics as pull-backs of spatial distributions." Journal of the Mechanics and Physics of Solids, 89:59-76, 2016
• N. C. Admal, E.B. Tadmor. "The non-uniqueness of the atomistic stress tensor and its relationship to the generalized Beltrami representation." Journal of the Mechanics and Physics of Solids, 93:72-92, 2016. Special Issue in honor of Michael Ortiz
• N. C. Admal, E. B. Tadmor. "Stress and heat flux for arbitrary multibody potentials: A unified framework." The Journal of Chemical Physics, 134:184,106, 2011
• N. C. Admal, E. B. Tadmor. "A unified interpretation of stress in molecular systems." Journal of Elasticity, 100:63-143, 2010

Pending Articles

• Jaekwang Kim, Matt Jacobs, Stanley Osher, N. C. Admal. "A crystal symmetry-invariant Kobayashi-Warren-Carter grain boundary model and its implementation using a thresholding algorithm." Journal of Computational Materials Science, Under review.

Invited Lectures

• "Polycrystal plasticity with grain boundary evolution - A framework to model recovery, recrystallization and grain growth.", University of Minnesota, Minneapolis, Oct 2019
• "Modeling 3-D grain boundary evolution driven by the five-dimensional grain boundary energy landscape", Dislocations conference, Technion-Israel Institute of Technology, Haifa, Sep 2019
• "Polycrystal plasticity with anisotropic grain boundary evolution." USACM Thematic Workshop on "Recent Advances in the Modeling and Simulation of the Mechanics of Nanoscale Materials", University of Pennsylvania, Philadelphia, Aug 2019.
• "Plasticity in extreme environments: Recrystallization and grain growth." Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, Apr 2018
• "Plasticity in extreme environments: Recrystallization and grain growth." Department of Materials Science and Engineering, University of Arizona, Tucson, Tucson, AZ, Apr 2018
• "Plasticity in extreme environments: Recrystallization and grain growth." Department of Mechanical Science and Engineering, University of Illinois at Urbana Champaign, Urbana-Champaign, IL, Mar 2018
• "Plasticity in extreme environments: Recrystallization and grain growth." Department of Mechanical Engineering, State University of New York at Buffalo, Buffalo, NY, Mar 2018
• "Grain growth in dynamic recrystallization." School of Engineering, Brown University, Providence, RI, Mar 2017
• "Grain growth in dynamic recrystallization." Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, Mar 2017
• "Bridging atomistic, mesoscale and continuum models for materials." Department of Mechanical En- gineering, University of Houston, Houston, TX, Apr 2016
• "The atomistic representations of strain gradient elasticity tensors." 2nd Schontal Symposium: Dislocation based Plasticity, Schontal, Germany, Feb 2016
• "The non-uniqueness of the atomistic stress tensor and its relationship to the generalized Beltrami representation." Fifteenth Pan-American Congress of Applied Mechanics, Champaign, IL, May 2015

Patents

• Nikhil C. Admal, Parag Thakre, Atanu Phukan, Sriharsha Aradhya. MEMS flow sensor. Number US 7337678 B2. Issued March 2008

Reports

• Junyan He, N. C. Admal. "A study of the beveling instability in solenoid conductors.", A report submitted to FermiLab, 2020

Conferences Organized or Chaired

• SES 2020, Symposium co-organizer, Grain boundary and Interfacial mechanics
• SES 2020, Scientific track co-chair, Advances in Nanomechanics
• MMM 2018 Symposium co-organizer, Crystal plasticity and discrete defect mechanics
• USNCCM 2015 Symposium co-organizer, Atomistic computation of continuum quantities

Honors

• Institute for Digital Research and Education (IDRE) Postdoctoral Fellowship, University of California Los Angeles (2016)
• Doctoral Dissertation Fellowship, University of Minnesota, Minneapolis (2012-2013)

Teaching Honors

• Listed in "Teachers ranked as excellent" by the Center for Innovation in Teaching & Learning (CITL) for Spring 2019

Improvement Activities

• AE3 Collins Scholar, 2019

Recent Courses Taught

• TAM 210 - Introduction to Statics
• TAM 211 - Statics
• TAM 445 - Continuum Mechanics
• TAM 456 - Experimental Stress Analysis
• TAM 574 (CSE 517) - Adv Finite Element Methods