Symposium PM05—Electromagnetic Fields in Materials Synthesis—Far from Equilibrium Effects
Electromagnetic (EM) fields absorbed within a material can promote far-from-equilibrium chemical reactions and/or phase transformations. Here we define far-from-equilibrium as a type of dynamic equilibrium in which the phase of a material is changing due to external excitation sources like EM fields. Low temperature (< 200 oC) crystallization in ceramic materials, induced by both microwave radiation in the 0.3-300 GHz frequency range and lasers with frequency in the mid infrared range are two examples of such transformations. Ceramic crystallization under conventional synthesis conditions requires high temperatures exceeding 500-1000 oC. Advances in techniques like flash sintering are even able to achieve remarkable densification of ceramic powders in seconds, while conventional sintering at high furnace temperatures for several hours is typically required to achieve similar results.
What is common to these examples is the idea that the EM fields absorbed within a material may not be immediately converted to heat, but can instead result in far-from-equilibrium “non-thermal” effects. A lot remains to be understood about the fundamental mechanisms underlying such interactions of EM fields with matter, especially in the microwave region of the spectrum. From an industrial standpoint, processing advanced materials using electromagnetic fields can have a smaller energy footprint compared to conventional synthesis and as such will have a profound impact on society. These materials will additionally find use in diverse areas like sustainable infrastructure, transportation, clean energy, water management, healthcare.
The proposed symposium will encourage collaboration between the research communities that use electromagnetic fields (such as but not limited to microwave radiation and lasers) for materials synthesis, in academia, industry, and government laboratories. The symposium will foster focused scientific discussions towards identifying underlying mechanisms that are responsible for the far-from-equilibrium effects of electromagnetic fields (e.g., low temperature crystallization, sintering) that have been observed by both microwave and laser communities, but to this day remain un-explained. By bringing these communities together at MRS, this symposium will provide an interactive platform for cross-pollinating advances made by both communities as well as to explore ideas to bring them closer scientifically. The continuing goal will be to establish a multidisciplinary community spanning experimental and theoretical/computational research groups to focus on examining the role of experimentation and theoretical modeling as well as advanced characterization techniques in developing a fundamental understanding of the role of electromagnetic fields in the rational design and molecular scale synthesis of materials.
A half day TUTORIAL on Flash Sintering by Rishi Raj (University of Colorado – Boulder, USA) is tentatively planned. The symposium organizers will also award prizes to the two best presentations by student/postdoctoral fellows.