Polycrystals are prototypical microstructures - they are ubiquitous, the microstructure plays a key role in many properties, they evolve in response to a wide-range of driving force, and yet are amenable to theoretical analysis and simulation. I briefly review the classical 2d analyses of normal grain growth and our recent exact extension to all dimensions. We use this result to develop accurate simulations of the coarsening of a polycrystalline microstructure in 3d with up to one hundred million grains. This scale is comparable with macroscopic experimental samples and a scale that exceeds that of the largest three-dimensional experiments with microstructural resolution. The simulations allow us to discover new microstructural relationships and interpret new experiments. Next, I turn to the question of how polycrystalline microstructure affects the mechanical deformation of nanocrystalline wires. Here, we employ atomistic simulations with grain and sample sizes comparable to recent experiments. Because the simulations are on the experimental scale and have atomistic resolution, we gather new insights into the interaction between microstructure and a plethora of deformation mechanisms.
Biography:
David J. Srolovitz is the Joseph Bordogna Professor of Engineering and Applied Science at the University of Pennsylvania, where he is also a professor of Materials Science and Engineering and of Mechanical Engineering and Applied Mechanics and Director of the Penn Institute for Computational Science. His research is on the structure and properties of defects in crystals, microstructure and morphology evolution, and the mechanical behavior of nanoscale materials. He has published more than 400 research papers and has an h-index of 69. He is a fellow of the Materials Research Society, TMS, and ASM International and has given honorary lectures around the world. He has outstanding paper awards from Acta Materialia, American Institute of Chemical Engineers, and NASA. He has served as Editor-in-Chief or on the executive editorial boards of 10 different journals. Born in 1957 in Milwaukee, Srolovitz received his BS in Physics from Rutgers University (1978), and his MSE (1980) and PhD (1982) degrees in Materials Science and Engineering from the University of Pennsylvania. After postdoctoral work at Exxon Corporate Research (1982), he was a staff member at Los Alamos National Laboratory (Theory and Materials Divisions - 1984), professor at the University of Michigan (Materials Science and Engineering & Applied Physics -1987), professor at Princeton University (Mechanical and Aerospace Engineering & Applied Mathematics - 1999), Dean of Yeshiva College 2006), and Executive Director of the Institute of High Performance Computing in Singapore (2009). He has supervised over 45 PhD students and postdoctoral associates.

The structure of materials invariably defines their mechanical behavior. However, in most materials, specific mechanical properties are controlled by structure at widely differing size-scales, literally from atomistic to near-macro dimensions. Here we explore the use of real time mechanical and structural characterization of both biological materials, e.g., human bone, and engineering materials, e.g., ultrahigh-temperature ceramic composites, to discern the origins of their strength and toughness properties at multiple length-scales. Specifically, we examine the use of macro-scale fracture mechanics testing coupled with in situ micro-scale imaging in the environmental scanning electron microscope, in situ tensile tests with simultaneous nano-scale small-angle and wide-angle x-ray scattering/diffraction in the synchrotron, and the real time quantitative 3-D micro-scale characterization of damage in textile composites under load at temperatures as high as 1850°C using x-ray computed tomography. The applications with respect to bone include discerning the structural origins of its damage-tolerance and identifying how biological factors such as aging and disease can degrade this; with respect to ceramic composites the quantification of the damage mechanisms under load at temperature provides crucial input for computational and statistical models for life prediction.
Biography:
Robert Ritchie is currently the H.T. & Jessie Chua Distinguished Professor of Engineering in the Materials Science & Engineering and Mechanical Engineering Departments at the University of California at Berkeley; he is also Senior Faculty Scientist at the Materials Sciences Division at the Lawrence Berkeley National Laboratory (LBNL). He received his B.A., M.A., Ph.D. and Sc.D. degrees in Materials Science from Cambridge University, where he was the Goldsmith&’s Junior Research Fellow in Metallurgy at Churchill Collage from 1972-74. He first came to the U.S. in 1974 as a Miller Research Fellow at Berkeley. Following nearly five years on the Mechanical Engineering Faculty at M.I.T, he joined the faculty at Berkeley in 1981 where he was Director of the Center for Advanced Materials at LBNL from 1987-95 and Chair of the Materials Science & Engineering Department on Campus from 2005-11. He is known for his research into the mechanics and mechanisms of fracture and fatigue of a broad range of structural and biological materials, spanning steels and aluminum through ceramics and composites to bone, teeth and fish scales. Currently his research interests are focused on the development of bio-inspired lightweight structural materials, issues of damage and fracture in metallic glasses and high-temperature composites, and the biological degradation of the structural integrity of bone. He is a member of the National Academy of Engineering, the Russian Academy of Sciences and the Royal Academy of Engineering in the U.K.

Phonons - quanta of crystal lattice vibrations - reveal themselves in all electrical, thermal and optical phenomena in materials. Acoustic phonons carry heat and limit electron mobility while optical phonons affect the light - matter interactions. Nanostructures open opportunities for tuning the phonon spectrum and related properties of materials for specific applications, thus realizing what was termed phonon engineering or nanophononics. A recent advent of graphene and quasi two-dimensional van der Waals materials resulted in a discovery of a wealth of new phonon physics and created opportunities for better control of phonon transport and interactions. In this talk, I will describe the measurements of the phonon thermal conductivity of graphene using the optothermal Raman technique; explain physical phenomena leading to the anomalous behavior of the thermal conductivity of graphene; and outline practical applications of graphene in thermal management of electronic devices and circuits. The unique phonon properties of a broad class of van der Waals materials and semiconductor nanostructures will also be discussed. Specifically, I will address the issues of increasing the thermoelectric figure of merit in stacks of layered materials, modification of the transition temperature to the charge-density-wave phase and the use of Raman spectroscopy as nanometrology tool for quasi two-dimensional crystals.
Biography: ALEXANDER A. BALANDIN is currently Professor of Electrical Engineering and Founding Chair of Materials Science and Engineering at the University of California - Riverside (UCR). He received his MS (1991) degree Summa Cum Laude in Applied Physics and Mathematics from the Moscow Institute of Physics and Technology (MIPT), Russia, and PhD (1997) degree in Electrical Engineering from the University of Notre Dame, USA. Prior to joining UCR, he worked as a Research Engineer at UCLA. In 2005, he spent his sabbatical as a Visiting Professor at the University of Cambridge, U.K. His research interests are in the area of advanced materials, nanostructures and nanodevices for electronic, optoelectronic and direct energy conversion applications. He conducts both experimental and theoretical research. His work resulted in over 190 journal publications, which were cited ~14,000 times (h>55). Professor Balandin is a recipient of the IEEE Pioneer Award in Nanotechnology for 2011. He was recognized by the National Science Foundation CAREER Award, ONR Young Investigator Award, UC Regents Award, and Merrill Lynch Innovation Award. He is a Fellow of the American Physical Society, Optical Society of America, The Institute of Electrical and Electronics Engineers, International Society for Optical Engineering and the American Association for the Advancement of Science. He is an Editor of IEEE Transactions on Nanotechnology and an Associate Editor of Applied Physics Letters. He supervised more than 20 PhD students who presently carry out R&D work in industry, government laboratories and academia. The work of his Nano-Device Laboratory (NDL) has been supported by NSF, DARPA, ONR, AFOSR, SRC, NASA and semiconductor industry.

Moderator: Tia Benson Tolle, Boeing Corporation
Big Data and Open Data are topics of increasing interest and discussion in the materials community. Advances in computational modeling are introducing a paradigm shift in how research is conducted and how data is analyzed and shared. Broad access to data holds the promise for advancing the speed to new discoveries. However, it also raises questions relating to quality, validation, reproducibility and intellectual property.
Building from a series of features in MRS Bulletin and Materials360® Online, this session seeks to expand the community dialogue on Big and Open Data for Materials Research through a panel of experts with diverse perspectives:
Rick Barton, Lockheed Martin
Nicola Marzari, École Polytechnique Fédérale de Lausanne, Switzerland
Jim Pinkleman, Microsoft Research
Mary Galvin, National Science Foundation Division of Materials Research
J. Michael Simonson, Oak Ridge National Laboratory