Journal of the American Ceramic Society Awards Symposium: JACerS Awards Symposium Session II
Program Organizers: William Fahrenholtz, Missouri University of Science and Technology
Wednesday 2:00 PM
October 17, 2018
Location: Greater Columbus Convention Center
Session Chair: William Fahrenholtz, Missouri University of Science and Technology
2:00 PM Invited
Emerging Opportunities in Ceramics and Glass Research: Follow-up from a 2016 NSF Workshop: Katherine Faber1; 1California Institute of Tech
Under the sponsorship of the U.S. National Science Foundation, a workshop on emerging research opportunities in ceramic and glass science in September 2016 resulted in a report highlighting eight challenges. Research themes spanned ceramic processing, defect science, two-dimensional ceramics, glasses and ceramics in extreme environments, and materials design and predictive modeling. If successfully addressed, these lines of inquiry will advance our basic understanding of ceramics and glasses, while enabling technological advancements across the energy, environment, manufacturing, security, and health care sectors. In this presentation, the main features of the report will be reviewed along with an assessment of how the report has influenced current research support and trends. Some examples of the latest research addressing the challenges will also be offered.
2:30 PM Invited
Current Understanding and Future Research Directions at the Onset of the Next Century of Sintering Science and Technology: Rajendra Bordia1; Suk-Joong Kang2; Eugene Olevsky3; 1Clemson Univ; 2Korea Advanced Institute of Science and Technology (KAIST); 3San Diego State University
Sintering and accompanying microstructural evolution is inarguably the most important step in the processing of ceramics and hard metals. Developing new and perfecting existing sintering techniques is crucial to meet ever-growing demand for a broad range of technologically significant systems including, for example, fuel and solar cell components, electronic packages and elements for computers and wireless devices, ceramic and metal-based bio-implants, thermoelectric materials, materials for thermal management, and materials for extreme environments. In this presentation, the current state of the science and technology of sintering is presented. Focus will be on topics of current research, including the sintering of composites, multilayered systems, microstructure-based models, multi-scale models, sintering under external stresses and innovative and novel sintering approaches, such as field assisted sintering. The status of these sub-fields, the outstanding challenges and opportunities, and the outlook of progress in sintering research will be presented.
3:00 PM Invited
Mobility Transition is the Mechanism behind Two-step Sintering: Yanhao Dong1; I-Wei Chen2; 1Massachusetts Institute of Technology; 2University of Pennsylvania
Two-step sintering has been successfully practiced in a variety of systems producing fine-grain ceramics with superior properties. The hallmark of the low-temperature second step is extensive densification without grain growth, so the diffusion kinetics must remain robust yet the grain boundary mobility is somehow suppressed. Since two-step sintering is widely applicable to ceramics, this must be a rather general phenomenon insensitive to the types of crystal structures, rate-limiting defects and kinetics/property-altering dopants. Our measurement of the grain boundary mobility in yttria-stabilized cubic zirconia confirmed such transition at 1300oC, below which the activation energy becomes unphysically large. Surprisingly, the microstructure below the transition temperature can locally bifurcates into abnormally small/large-grain clusters, which can be explained by mean-field theory and simulations. The implications on two-step sintering shall be discussed.
3:30 PM Break
4:00 PM Invited
Characterization and Modeling of Microstructural Level Stresses in Alumina: Melissa Teague1; Theron Rodgers1; Scott Grutzik1; Stephen Meserole1; 1Sandia National Laboratories
Brittle failure is often influenced by difficult to measure and variable microstructure scale residual stresses. Recent advances in photoluminescence (PL) spectroscopy, including improved confocal laser measurement and rapid data collection spectroscopic data have established the potential to map residual stress variating with microscale spatial resolution (<2 microns) To investigate the limits of PL spectroscopy as a microscale stress mapping tool, results from the mapping stress generated in bonded, mis-oriented bi-crystals, and polycrystalline alumina. These results will be compared to microstructure models generated from electron backscatter diffraction (EBSD) to highlight the advances and limits of currently modeling capability to predict stresses within complex microstructures.Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.
4:30 PM Invited
Viscosity of Glass-forming Systems: From Medieval Stained Glass Windows to Advanced Functional Glasses: John Mauro1; 1The Pennsylvania State University
As one of the most important properties of glass-forming systems, viscosity has drawn significant attention in both manufacturing and fundamental research. I will review the recent scientific progress in viscosity of glass-forming systems, including both the liquid and glassy states. Temperature-dependent constraint theory is introduced as a powerful tool for predicting the composition dependence of viscosity. Some examples of the application of this approach to predict dynamics of various glass systems are shown. I will also discuss recent work related to the flow of medieval cathedral glass windows and the relaxation behavior of advanced functional glasses.
5:00 PM Invited
Energetics and Structure Relations of Solid Phases in Silicon–oxygen–carbon System: Jiewei Chen1; Sean King2; Alexandra Navrotsky3; 1University of California Davis; 2Intel Corporation; 3Peter A. Rock Thermochemistry Laboratory and NEAT ORU, University of California Davis
The silicon–oxygen–carbon system includes a variety of materials of technological and scientific importance. However, there are currently no known thermodynamically stable crystalline compounds comprised of all three elements. In contrast, amorphous materials that combine all three components are relatively common and of interest for numerous electronic, optical, thermal, mechanical, nuclear and biomedical applications. Our work focuses on understanding the underlying thermodynamic reason behind this broad group of materials and their structure–energetics relationships. Starting from polymer-derived ceramics synthesized by pyrolysis of polymeric precursors and progressing to amorphous low-dielectric constant films by plasma-enhanced chemical vapor deposition, we have determined the thermodynamic parameters of a wide range of Si-O-C materials and analyzed their structures. The unique thermodynamic stability seen in a number of these materials can be attributed to the presence of nanodomains, special bonding configurations involving silicate tetrahedra containing both carbon and oxygen, and organic functional groups containing hydrogen.
5:30 PM Invited
Environmental Resistance of Cr2AlC MAX Phase at High Temperature: Jesus Gonzalez-Julian1; Olivier Guillon1; Robert Vassen1; 1Forschungszentrum Jülich
MAX phase materials are promising candidates to operate under harsh and aggressive environmental conditions. Among all of them, Cr2AlC is one of the most potential candidates for high temperature applications (1000 ̊C – 1300 ̊C) due to the in-situ formation of an external and protective α-Al2O3 layer. However, the response of Cr2AlC – and other MAX phases – has been practically unexplored in long-term experiments under realistic and environmental conditions at high temperature.In this work, Cr2AlC materials have been performed by different processing techniques to obtain highly dense substrates, composites and porous structures, as well as coatings by cold-spray. The oxidation resistance and the response of these systems at high temperature will be analyzed under realistic environmental conditions using a burner rig. Furthermore, interaction between Cr2AlC substrates and Thermal Barrier Coatings (TBCs) will be analyzed in detail.
6:00 PM Concluding Comments