Oxidation of Rare-Earth Silicate Multilayer EBCs
Student: Benjamin Herren
Due to their high melting temperature, low density, and good thermomechanical stability silicon-based ceramics (SiC, Si3N4) are one of the most promising materials systems for high temperature structural applications in gas turbine engines. However, their passivating SiO2 surface layer reacts with water vapor contained in combustion environments. Read More...
Student: Benjamin Herren
Due to their high melting temperature, low density, and good thermomechanical stability silicon-based ceramics (SiC, Si3N4) are one of the most promising materials systems for high temperature structural applications in gas turbine engines. However, their passivating SiO2 surface layer reacts with water vapor contained in combustion environments. Read More...
Multi-functional Ceramic Composites of Boron Nitride
Student: Celia Chari
Hall-effect thrusters used in electric propulsion systems have historically required a dielectric such as hexagonal boron nitride (h-BN) that has good thermal emissivity, is chemically inert and is resistant to thermal shock. However, the brittle nature of bulk BN poses challenges under dynamic loads, such as the launch environment, where the stiff material is subject to vibration and strain that can lead to catastrophic failures. Read More...
Student: Celia Chari
Hall-effect thrusters used in electric propulsion systems have historically required a dielectric such as hexagonal boron nitride (h-BN) that has good thermal emissivity, is chemically inert and is resistant to thermal shock. However, the brittle nature of bulk BN poses challenges under dynamic loads, such as the launch environment, where the stiff material is subject to vibration and strain that can lead to catastrophic failures. Read More...
Reverse Engineering Lusterware Porcelain
Student: Celia Chari
Meissen porcelain was Europe’s first successful replication of Chinese porcelain with decorative over-glaze enamels, invented by Johann Böttger in the early 18th century. A full pallet of colors was desired to replicate Chinese ceramics during the Böttger period of the Meissen factory’s production. While this goal was not realized for years to come, rare “mother of pearl” and lustrous purple glazes were produced by applying gold nanoparticles to the top glaze. Read More...
Student: Celia Chari
Meissen porcelain was Europe’s first successful replication of Chinese porcelain with decorative over-glaze enamels, invented by Johann Böttger in the early 18th century. A full pallet of colors was desired to replicate Chinese ceramics during the Böttger period of the Meissen factory’s production. While this goal was not realized for years to come, rare “mother of pearl” and lustrous purple glazes were produced by applying gold nanoparticles to the top glaze. Read More...
Reinforced Silicon Oxycarbide Composites via Freeze-Casting with Preceramic Polymers
Student: Claire Kuo
An established method of strengthening ceramics — adding reinforcement fillers — is integrated into freezing casting to strengthen silicon oxycarbide (SiOC) porous ceramics. Due to the nature of freeze casting process and differences in fillers, the reinforcing effects of fillers on freeze-cast ceramics are more complicated than that of conventional composites. Read More...
Student: Claire Kuo
An established method of strengthening ceramics — adding reinforcement fillers — is integrated into freezing casting to strengthen silicon oxycarbide (SiOC) porous ceramics. Due to the nature of freeze casting process and differences in fillers, the reinforcing effects of fillers on freeze-cast ceramics are more complicated than that of conventional composites. Read More...
Shape Memory Behaviors in Porous Zirconia-Based Systems
Student: Laura Quinn
Shape memory materials have been used in applications ranging from mechanical actuators to medical devices. By taking advantage of a diffusionless martensitic transformation between phases, these materials can either exhibit shape memory or superelastic effects. While these behaviors have most often been exploited in alloys, the martensitic transformation is also seen in zirconia-based ceramic systems. However, in zirconia-based systems, this phase transformation is accompanied by a volume change that can lead to premature cracking in bulk systems. Read More...
Student: Laura Quinn
Shape memory materials have been used in applications ranging from mechanical actuators to medical devices. By taking advantage of a diffusionless martensitic transformation between phases, these materials can either exhibit shape memory or superelastic effects. While these behaviors have most often been exploited in alloys, the martensitic transformation is also seen in zirconia-based ceramic systems. However, in zirconia-based systems, this phase transformation is accompanied by a volume change that can lead to premature cracking in bulk systems. Read More...
Fracture Mechanics of Brittle Materials Studied Using Synchrotron X-ray Radiation
Student: Sara Gorske
Fracture is a critical mode of failure in many materials, especially in brittle ceramics which undergo little plastic deformation. Most studies of fracture in the past have relied on ex-situ methods to assess fracture surfaces after a failure event, and while this mode of analysis has yielded key discoveries on the nature of cracks, research studying cracks in the interior of brittle materials as they are forming and growing has yet to be conducted in depth. In the Faber group, we are pioneering a new method of fracture study. Read More...
Student: Sara Gorske
Fracture is a critical mode of failure in many materials, especially in brittle ceramics which undergo little plastic deformation. Most studies of fracture in the past have relied on ex-situ methods to assess fracture surfaces after a failure event, and while this mode of analysis has yielded key discoveries on the nature of cracks, research studying cracks in the interior of brittle materials as they are forming and growing has yet to be conducted in depth. In the Faber group, we are pioneering a new method of fracture study. Read More...