Bulk metallic glasses (BMGs) offer a great deal of potential through their near-theoretical strength, potentially high toughness and unique forming and molding traits. However, there are still a number of outstanding issues that bar their widespread use. This thesis describes the investigation of three research questions each designed to further...
The research presented herein represents an effort to combine the ultra-smooth surface of an amorphous metal thin film (AMTF) with a solution-processed dielectric synthesized via prompt inorganic condensation (PIC). Analysis of dielectric film quality is carried out via electrical measurements of metal-insulator-metal (MIM) diodes. Anneals at 500 and 700 °C...
The objective of this thesis is to provide an initial demonstration of two-terminal and three-terminal electronic devices employing amorphous multi-component metallic film
(AMMF) electrodes. Such a demonstration is successfully achieved in the fabrication of metal-insulator-metal (MIM) diode and hot electron transistor (HETs) structures employing ZrCuAlNi AMMF electrodes. The ultra-smooth surface...
A Bulk Metallic Glass (BMG) is an amorphous solid with thickness greater than 1mm. Material properties of BMG, like twice the strength of regular steels and excellent corrosion resistance, make them ideal materials for fabrication of MEMS and MECS devices which have attracted a lot of research activity recently. Diffusion...
The effect of ambient environment on the fatigue behavior of two Zr-Ti-Cu-Ni-Be bulk metallic glasses (BMGs) is examined in the present study. The first metallic glass, Zr₄₄Ti₁₁Ni₁₀Cu₁₀Be₂₅, was tested to establish the presence of an environmental effect in the fatigue growth curve measured in ambient air. Fatigue growth curves produced...
Bulk metallic glasses (BMGs) are relatively new amorphous materials that have received much attention in recent years. Rapid cooling methods from the liquid state provides the possibility to bypass crystallization during solidification. Due to the lack of crystal defects such as grain boundaries and dislocations, BMGs can have some special...
Deformation of metallic glasses requires the existence of free volume to allow atomic movement under mechanical loading. Accordingly, the present research seeks to understand how free volume variations in alloys of identical compositions affect the fatigue and fracture behavior. By annealing below the glass transition temperature, the free volume of...
The influence of shear rate and temperature on the viscosity and fragility of the Zr₄₁.₂Ti₁₃.₈Cu₁₂.₅Ni₁₀.₀Be₂₂.₅ (Vit1) metallic glass forming liquid is measured in the liquid and undercooled liquid state between 907 and 1300 K. The results show a complex rheological behavior of Vit1. The viscosity of Vit1 is about three...
The heating rate dependence of the glass transition temperature of the
Ni₆₅Nb₃₅, Ni₆₀Nb₃₅Sn₅, Ni₅₉.₃₅Nb₃₄.₄₅Sn62, Ni₆₀(Nb₄₀Ta₆₀)₃₄Sn₆, and
Ni₅₇Fe₃Nb₃₅Sn₅ metallic glass forming alloys was investigated with a
differential scanning calorimeter (DSC). The inverse heating rate for each
DSC experiment was plotted versus inverse temperature and a Vogel-Fulcher-
Tamman (VFT) type relation was...
This paper documents the investigation into injection molding, or die casting, a bulk metallic glass (BMG). A BMG is an amorphous metal of a thickness greater than 25 μm, according to leading researchers in the field. This critical thickness differentiates a normal metallic glass from a "bulk" metallic glass. The...