The work presented in this dissertation focuses on ceramic anode materials for solid oxide fuel cells (SOFCs). The primary goal was to characterize the anode and relate the electrochemical behavior to the microstructure. The anode that was most extensively studied in this work was a composite of Gd0.10Ce0.90O1.95 (GDC) and...
For bone regeneration, there is need for biodegradable, synthetic scaffolds that direct the formation of <em>de novo</em> mineralized tissue. Orthopaedic implants additionally require mechanical function. The work described herein attempts to address both of these needs. The general strategy involves integrating molecularly designed tissue engineering scaffolds with porous metallic foams...
Dimensionally constrained material systems are at the forefront of current materials research because of their novel and often enhanced physical, chemical and biological properties. The dimensionality effects are pervasive through different classes of materials including ceramics, metals and polymers. Often times dimensionality effects are manifested as internal structure variations in...
Aluminum alloys strengthened with coherent (L1<sub>2</sub>), nanosize Al<sub>3</sub>Sc precipitates may be used as structural materials at elevated temperatures. They are creep resistant at 300°C and exhibit a threshold stress, below which creep is not measurable. Introducing ternary alloying additions, such as rare-earth elements (RE=Y, Dy, Er), that segregate within Al<sub>3</sub>Sc...
A series of investigations was undertaken to explore the processing and properties of porous titanium with 6 wt% Al and 4 wt% vanadium (Ti-6Al-4V) and an equiatomic nickel-titanium alloy (NiTi). In this study, porous materials were created in the solid state by entrapping argon in a powder compact, and subsequently...
This thesis examines the effects of micro-alloying additions to Al-Sc alloys on the microstructure, coarsening resistance and creep properties. The overarching goal of this research is to develop castable, creep-resistant aluminum alloys which can be used at temperatures in excess of 300?C. Successful high-temperature application of aluminum based alloys offers...
In this dissertation, the Tg behavior of nanoconfined polymer films and 1-dimensional (1-D) patterned polymer nanostructures was studied. Using a novel fluorescence method, a reduction in Tg was observed upon confinement in PS films supported on silica, where free-surface (polymer-air interface) effects are dominant in modifying Tg. In contrast, Tg...
Because soft materials, particularly polymer gels, are playing a greater role in industrial and biotechnological applications today, the exploration of their mechanical behavior over a range of deformations is becoming more relevant in our daily lives. Understanding these properties is therefore necessary as a means to predict their response for...
Gradient copolymers are novel materials that possess a gradual variation in composition along the chain, thereby forming an intermediate structure between random and block copolymers. As such, they are a model system to investigate the effect of molecular structure on fundamental properties of copolymers and may be useful in many...
In this work, the processing of the superconductor MgB<sub>2</sub> was studied to create a fundamental scientific background for the production of superconducting composite wires. The synthesis of MgB<sub>2</sub> from Mg and B powders was investigated in situ to determine reaction rates and kinetic parameters for the application of powder-in-tube technology...