The Faber Group’s research spans brittle materials, largely ceramics, as they relate to the fundamentals of fracture, performance in extreme environments, energy systems, filtration and flow for sustainability and medicine, and cultural heritage science.
Advanced Materials for Extreme Environments
Ceramics are extremely useful in high-temperature and space applications, especially those with harsh chemical environments. In conjunction with NASA and the Jet Propulsion Laboratory, we explore such systems as
• Environmental barrier coatings in harsh chemical environments, with special focus on interaction with calcium-magnesium-alumino-silicates and water vapor
• Bimaterial systems of hexagonal boron nitride and graphite, created using carbothermal reactions, for electric propulsion components with new electrical and thermal properties
• Molten regolith electrolysis of lunar regolith for oxygen production
• Laser-powder bed fusion combined with reaction bonding to avoid thermal shock when additively manufacturing ceramic bodies, specifically focusing on controlling oxidation and sintering to optimize the final components
Tuning Pores in Ceramics to Optimize Functionality
Our group has performed many freeze-casting experiments to tailor the size, shape, and directionality of pores in ceramic bodies. Such tunability allows advancement in various fields, and fosters collaboration with other Caltech groups including those of Professor Julie Kornfield (Chemical Engineering) and Professor Victoria Orphan (Geological and Planetary Sciences).
• Real-time imaging of bacterial colonization under high-temperature and high-pressure environments simulating deep ocean habitats requires biocompatible materials with chemical and mechanical robustness as well as a refractive index close to that of water
• Different filtration systems require different levels of surface functionalization as well as tunable flow speed which can be controlled via changing pore dimensions and anisotropy
• Porous zirconia systems under pressure can activate a martensitic transformation without cracking, enabling the creation of macroscale ceramic shape-memory or superelastic systems
Synchrotron Studies of Fundamental Material Properties
Synchrotron X-rays at Argonne National Laboratory’s Advanced Photon Source reveal information about material microstructures and transformations with high precision.
• Environmental barrier coatings can be studied in-situ under cyclic temperature and chemical conditions to investigate the development of internal stresses and the extent of oxidation
• The combination of micro-computed tomography and high-energy diffraction microscopy allows a crack to be grown in-situ, while tracking the geometry of the crack front and the nature of the surrounding microstructure
Materials Science in Art, Archaeology, and Art Conservation
Our involvement with local museums, as well as the Northwestern University/Art Institute of Chicago Center for Scientific Studies in the Arts (NU-ACCESS), showcases the value of materials science to cultural heritage science.
• Characterization and reverse engineering has revealed the effect of gold nanoparticles on 18th-century German lusterware
• Collaboration with computational chemists has fueled studies of sulfuric acid on archaeological analogs to investigate climate change-driven environmental degradation of cultural heritage pieces
For more information on each of these projects, please explore our research page.