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Project #1: Plasma Diagnostics for the Deposition of Nano-materials |
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Problem
Statement:
Millions of dollars are spent in the development of advanced coatings, but
experience has shown that scale-up is often difficult due to significant,
unpredictable variations. Plasma diagnostics will thus be performed in an
inverted cylindrical magnetron sputtering system used to deposit nano-films
on cutting tools to aid this scale-up process. Objectives and Research Plan: The objective is to use state-of-the-art plasma diagnostic systems – optical emission spectroscopy, residual gas analysis, and Langmuir probe – to quantitatively and spatially measure neutral and charged atomic and molecular ground state and excited state number densities and energy, and electron number density and energy. Critical parameters which will be investigated include pressure, power, gas composition, substrate bias voltage, magnetic field configuration, and pulsed versus alternating current power configuration. One specific task for the intern, spatially mapping the electron density, for example, will be determined when the intern arrives. Training Plan: Weeks 1-2: plasma fundamentals; Weeks 2-3: plasma diagnostic. Research Facilities: Surface Engineering and Advanced Materials Processing Laboratory |
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Project #2: Molecular Dynamic Simulations to Minimize Stress Induced Curvature |
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 Dr. Joseph J. Rencis, P.E. Professor and Head of Mechanical Engineering Program co-Director E-mail: jjrencis@uark.edu V-mail: 479-575-4153 |
Problem Statement:
Stress induced during the fabrication of thin-film devices is the main
cause of curvature in thin-films. Curvature affects the performance of
thin-films used in Micro-Opto-Electro-Mechanical System devices. One way
to reduce curvature is through argon ion bombardment on the silicon
substrate. This causes the amorphization of the surface modifying the
stress gradient through the film thickness. The simulation of the entire
process is carried out using molecular dynamic simulation to asses the
stress and curvature variation due to ion bombardment. |
| Project #3: Percolation Phenomena in Nano-Particle Composites | |
 Dr. Adam Huang Assistant Professor of Mechanical Engineering E-mail: phuang@uark.edu V-mail: 479-575-4054 |
Problem
Statement:
Conductive nano-particle composites can provide new capabilities as
sensing elements for micro/nano-devices. However, the non-linear
electro-conductivity characteristics of the nano-particle composites are
needed for successful application in micro/nano-devices. |
| Project #4: Fundamental Nanomanufacturing Processes for High Precision NanoEDM | |
 Dr. Ajay Malshe Professor of Mechanical Engineering and 21st Century Chair of Materials, Manufacturing and Integrated Systems E-mail: apm2@uark.edu V-mail: 479-575-6561 |
Problem Statement:
In nanoEDM, scanning nano tool tips are placed within 10nm
of a substrate. A train of electric pulses is applied between the tool and
substrate, immersed in dielectric oil medium. Developing a predictive
manufacturing process for application specific high precision nano tool
tips of various geometries is challenging though vital for nanoEDM. |
| Project #5: Role of Oxidation in Time-Dependent Crack Growth in Ni Base Superalloys | |
 Dr. Ashok Saxena Professor of Mechanical Engineering, Dean, and Distinguished Professor & 21st Century Graduate Research Chair of Materials Science & Engineering E-mail: asaxena@uark.edu V-mail: 479-575-3054 |
Problem Statement:
New and accurate models are needed to predict the
dwell-time effects on the fatigue crack growth behavior in turbine disk
materials at elevated temperatures. Damage effects include creep,
fatigue, environment and microstructure. |
| Project #6: Influence of Porosity on the Mechanical Behavior of FCC Metals | |
 Dr. Douglas Spearot Assistant Professor of Mechanical Engineering E-mail: dspearot@uark.edu V-mail: 479-575-3040 |
Problem Statement:
It is well established that vacancies and other point defects can serve as
preferential sites for dislocation nucleation; however, the precise
influence of vacancy distribution on mechanical properties is not well
understood. |
| Project #7: Carbon Nanotube Based Microsensor | |
 Dr. Steve Tung Associate Professor of Mechanical Engineering E-mail: chstung@uark.edu V-mail: 479-575-5557 |
Problem Statement:
The development of micro and nanoscale biomedical sensors
has become increasingly important in recent years due to concerns of
homeland security and rising health care costs. Carbon nanotubes, with
their naturally small size and remarkable material properties, provide an
ideal building block for manufacturing ultrasensitive sensors at the
nanoscale. |
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Project #8: Atomistic Fracture Simulations of Monolayer Graphene Sheets |
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 Dr. Sulin Zhang Assistant Professor of Mechanical Engineering E-mail: szhang1@uark.edu V-mail: 479-575-6701 |
Problem Statement:
Graphene sheets are an attractive alternative for polymer reinforcement
since they are less costly than carbon nanotubes, but have comparable
mechanical properties. This research will study the fracture strength of
monolayer graphene sheets using atomistic simulations.
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Project #9: Mechanical and Tribological Properties of Nano-textured Surfaces |
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 Dr. Min Zou Assistant Professor of Mechanical Engineering E-mail: mzou@uark.edu V-mail: 479-575-6671 |
Problem Statement:
Tribological issues affect the production yield
and product reliability
in nano-electro-mechanical systems due to the
large surface-area-to-volume ratios. Our research effort focuses on
surface nano-texturing to improve tribological performances in
miniaturized systems. |
