Materials Science and Engineering Commons^™

Metal Thin Film Stiffness Extraction Technique For Surface Acoustic Wave Filters, Travis R. Weismeyer

Electronic Theses and Dissertations

Accurate knowledge of the surface acoustic wave (SAW) properties propagating at the surface of a piezoelectric substrate with thin films, electrodes or temperature compensated films, is critical in SAW filter design to meet the target frequency response, power durability and performance prior to device fabrication. While reliable material constants exist for substrates such as LiNbO3 used in SAW filters, the absolute elastic constants associated with operational thin films used for electrodes or temperature compensation do not exist. Although the bulk values of the constituent materials are known, the composite film/substrate properties are difficult to predict since they depend strongly on …

Strategies For The Stabilization Of Metal Anodes For Li And Na Metal Batteries, Yang Zhao

Electronic Thesis and Dissertation Repository

Li-metal batteries (LMBs) and Na-metal batteries (NMBs) are considered as the promising candidates to replace the conventional Li-ion batteries (LIBs) due to their high theoretical energy density. For LMBs and NMBs, Li metal and Na metal are the ultimate choices to achieve their high energy density due to the high specific capacity, low electrochemical potential and lightweight. However, as alkali metals, both Li and Na metal anodes suffer from serious challenges including 1) Li/Na dendrite formations and short circuits; 2) Low Coulombic efficiency (CE) and poor cycling performance; and 3) Infinite volume changes. This thesis mainly focuses on the design …

Optimization Of The Practice Of Slow Cooling Steel Bars: A Redesign And Modernization Of Materials, Eryn Johnston

Mechanical Engineering Undergraduate Honors Theses

Throughout the process of steel making, certain grades of steel are a higher risk for defects caused by the inability to quickly diffuse hydrogen through the steel when cooled to room temperature at a normal rate based on the ambient air temperature. To reduce the hydrogen flaking defects that are caused due to hydrogen entrapment in the steel, the process of slow cooling is utilized. This process reduces the cooling rate of steel bars by keeping them at a higher temperature for extended periods and in turn gives the hydrogen a chance to fully dissipate from the steel. In many …

Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe

Mechanical Engineering

Reinventing the Wheel selected tires and designed wheels for the 2018 Cal Poly, San Luis Obispo Formula SAE combustion vehicle. Available tire options were evaluated for steady-state and transient performance as well as vehicle integration. A single-piece composite wheel with hollow spokes was designed to meet stiffness, strength, and tolerance requirements. A detailed study of wheel loading and geometric structural efficiency was performed. Finite element analysis was used to iterate the geometry and laminate. A two-piece male mold was designed and machined to manufacture the wheel. Removable silicone inserts were used to create the hollow spokes.

Low Temperature Desiccants In Atmospheric Water Generation., Sunil Gupta

Electronic Theses and Dissertations

Surging global water demand as well as changes to weather patterns and over exploitation of natural water sources, such as ground water, has made potable water a critical resource in many parts of the World already – one rapidly heading towards a crisis situation. Desalination has been adopted as a solution – this is however energy intensive and impractical for most of the developing countries - those most in need of water. A renewable source of energy is solar thermal and solar photovoltaic. A plentiful source of water is the humidity in the atmosphere. This research is to push the …

Characterization Of Nanomaterials For Thermal Management Of Electronics, Amit Rai

Doctoral Dissertations

Recently, there has been a growing interest in flexible electronic devices as they are light, highly flexible, robust, and use less expensive substrate materials. Such devices are affected by thermal management issues that can reduce the device’s performance and reliability. Therefore, this work is focused on the study of the thermal properties of nanomaterials and the methods to address such issues. The goal is to enhance the effective thermal conductivity by adding nanomaterials to the polymer matrix or by structural modification of nanomaterials. The thermal conductivity of copper nanowire/polydimethylsiloxane and copper nanowire/polyurethane composites were measured and showed more than threefold …

Effective Magnetic And Electric Response Of Composite Materials, Mona Hassan Alsaleh

Doctoral Dissertations

Metamaterials (MMs) are nanocomposite materials consisting of metal-dielectric resonators much smaller in size than the wavelength of the incident light. Common examples of metamaterials are based on split ring resonators (SRRs), parallel wires or strips and fishnet structures. These types of materials are designed and fabricated in order to provide unique optical responses to the incident electromagnetic radiation that are not available in naturally existing materials. The MMs can exhibit unusual properties such as strong magnetism at terahertz (THz) and optical frequencies. Additionally, negative index materials (NIMs) can provide negative index of refraction which can be used in many applications …

Electrical Characterization Of Graphene And Nanodiamond Nanostructures, A Z M Nowzesh Hasan

Doctoral Dissertations

The electrical characterization on two-dimensional carbon-based graphene and nanodiamond materials was performed to improve charge transport properties for the label-free electrical biosensors. The charge transport in solution-gated graphene devices is affected by the impurities and disorders of the underlying dielectric interface and its interaction with the electrolytes. Advancement in field-effect ion sensing by introducing a dielectric isomorph, hexagonal boron nitride between graphene and silicon dioxide of a solution-gated graphene field-effect transistor was investigated. Increased transconductance due to increased charge carrier mobility is accompanied with larger ionic sensitivity. These findings define a standard to construct future graphene devices for biosensing and …

Nanoparticle Catalytic Enhancement Of Carbon Dioxide Reforming Of Methane For Hydrogen Production, Nicholas Groden

Doctoral Dissertations

The U.S. produces 5559.6 million metric tons of carbon dioxide annually, of which 21% is produced by industrial processes. Steam reforming, an industrial process that accounts for 95% of all hydrogen production in industry, produces 134.5 million metric tons of carbon dioxide or around 11% of the total carbon dioxide produced by industry. This carbon dioxide is then either emitted or goes through a sequestration process that accounts for 75% of the plant's operational costs. An alternative reaction to steam reforming is dry reforming, which utilizes carbon dioxide rather than emitting it and can be used in conjunction with current …

Metal Segregation During The Solidification Of Titanium-Aluminum Alloys For 3d Printing Applications, Jwala Parajuli

Master's Theses

Titanium-Aluminum alloys are one of the widely used alloys in multiple engineering applications. They are highly preferred in Selective Laser Melting (SLM) processes due to their low density, high melting temperature, and good strength. Segregation occurs during the solidification of most alloys and produces a non-uniform distribution of atoms. In SLM, segregation may depict the type of adhesion between the two deposited interfacial layers and the strength between the interphase between an already solidified layer and a new one, and overall, the quality of the printed part. In order to avoid segregation, the understanding of the segregation behavior at atomistic …

Application Of Nano-Plasmonics For Sers Bio-Detection And Photocatalysis In The Same Platform, Muhammad R. Shattique

MSU Graduate Theses

Nano-biological systems interfacing nano-structured solid surfaces with biological compounds such as oligonucleotides or proteins are highly regarded as enabling materials for biosensing and biocatalysis applications. In particular, nanostructures of noble metals such as gold or silver, when exposed to light, exhibit a phenomenon known as surface plasmon resonance. When a proper metal nanostructure (plasmonic substrate) is exposed to light, very efficient absorption of incoming photons is possible, resulting in a buildup of localized high-energy regions, or “hot-spots”, where energetic carriers or “hot carriers” can be created. These hot-carriers can be used to catalyze desired chemical transformations in materials located nearby. …

Investigations On Hydrothermally Synthesized Co3o4/Mnxco3-Xo4 Core-Shell Nanoparticles, Ning Bian

MSU Graduate Theses

Two different morphologies (pseudo-spherical shaped or PS type and hexagonal nanoplate shaped or NP type) and two different concentrations (0.07 M and 0.1 M) of manganese incorporated Co₃O₄@Mn_xCo_3-xO₄ core-shell nanoparticles (CSNs) were investigated, respectively. The motivation of this work is to investigate the magnetic properties of, and specifically the exchange bias, between different shaped CSNs and between different Mn-doped CSNs. A two-step synthesis method was utilized to obtain the CSNs: a soft chemical approach was used to obtain Co₃O₄ nanoparticles and a hydrothermal nano-phase epitaxy was used to …

The Effects Of Atmospheric Heat Treatments On Tio2 Nanotube Anodes For Lithium-Ion Batteries, Andreas Savva

Boise State University Theses and Dissertations

The effects of various heat treatments on the physical and electrochemical properties of anatase TiO₂ nanotubes were studied in this work. Well-ordered TiO₂ nanotubes were grown via electrochemical anodization and annealed at 450°C to induce a phase transformation to anatase. The heat treatments were conducted under atmospheres of O₂, Ar, N₂, and water vapor (WV) to create different point defects. The oxygen-deficient atmospheres were used to generate oxygen vacancies in the TiO₂ nanotubes, while the water vapor treatment was used to create Ti vacancies by stabilizing them via the protonation of O sites. …

Phase Change Materials For Thermal Management Of Kennedy Library Study Rooms, Colin J. Empey

Materials Engineering

The overall purpose of this study was to find a phase change material (PCM) or a combination of PCMs as a thermal management solution for the fifth-floor study rooms in Kennedy Library. First and foremost, the PCM must take in heat to change phase. A PCM would be a better candidate the more heat it needs to change phase. To quantify this, the team utilized a DSC to find how much energy each candidate PCM required to change phase. Coconut oil, palm oil, and white chocolate were found to have the best ability to absorb heat. Secondly, the PCM should …

Development Of Test Methods For Measuring Fiber Misalignment And Warping In Honeycomb-Core Composite Panels, Wyatt Taylor, Haripriya Nilakantan

Materials Engineering

Zodiac Aerospace manufactures honeycomb-core composite panels to be used in aircraft cabin interior components. During the manufacturing process, some panels become warped such that they cannot be used for their designated aircraft cabin components. As a result, these panels are scrapped because they cannot be recycled. About 44 to 90% of panels become warped during manufacturing. Warping is caused by many factors, including layer misalignment, processing parameters such as temperature and pressure gradients, and fiber misalignment in the prepregs. Currently, Zodiac does not have any data on the effect of fiber misalignment on panel warpage, so a testing protocol was …

Next Generation Protocol: Innovating A Resilient Future, Andrew Steven Rudnick, Jamie Cannady, Joe Decesaro, Juan A. Ortiz Salazar

Materials Engineering

Conventional practices do not account for product life beyond end-of-sale – these practices are not sustainable. We have developed an end-of-life protocol that includes a metric that we call the Recovery Rating. The objectives of this Next Generation Protocol, beyond supporting the United Nations’ Sustainable Development Goals, are to encourage the production of goods designed for recovery and to promote the collaboration between consumers, the public, and the private sector to recover goods at their end-of-life. The Recovery Rating that we propose evaluates and quantifies recovery potential of products. The Recovery Rating, which is normed against embodied energy from the …

Solar Cell Potential Induced Degradation Sensor, Luc Alexandre Tousignant

Materials Engineering

It is important to maintain Photovoltaic (PV) cells and protect them from damage mechanisms like Potential Induced Degradation (PID), which can contribute to shorter lifespans and lower efficiencies. Current leakage through cell encapsulation can cause charge migration in PV cells that reduces the maximum quantum efficiency, which is the cause of PID. An experiment was setup to determine the feasibility of a non-silicon sensor able to produce similar leakage behavior to traditional PV cells under recorded humidity conditions. Thin sheet metals were encapsulated in EVA, a common PV encapsulant polymer, and mounted in aluminum framing. Three sensors, along with a …

In Situ Sem Solidification Study Of Ga And Egain: A Characterization Technique For Monitoring The Microstructural Evolution Of Liquid Metals, Jeremy Geovann Del Aguila

Materials Engineering

Scanning electron microscopy (SEM) video recording is used to characterize the solidification of small volumes of 99.999% pure gallium (Ga) and eutectic gallium-indium (eGaIn) under a high vacuum environment. Specimen are superheated to 55℃ using a hot plate, cast into spherical droplets, and cooled in situ by means of a Peltier cooling stage. Special attention is given to the preparation of the specimen prior to viewing because of gallium and its alloys’ nature to form an oxide layer when melted and air cooled. The oxide acts as a skin that inhibits the observation of microstructural features during solidification. Heated samples …

Analysis Of The Low-Cycle Fatigue Behavior Of Silicone Rubber For Biomedical Balloons, Chase Cooper

Materials Engineering

The development of a medical drug delivery device that allows for the deployment drugs into the adventitial tissue of blood vessels requires the inflation of a silicone elastomer. The inflated silicone must be able to consistently endure multiple loading cycles without failing so that the device can operate reliably. There are multiple methods of processing the silicone for the device and the goal of this study is to examine the effect of the various processing methods on the characteristics of the silicone. The Dynamic Mechanical Analysis Machine (DMA) is used to model the conditions of the device’s application by performing …

Composite Suspension For A Mass Market Vehicle, Sarah M. Chapiama, Brian Auyeung, Jose Guerrero, Ethan Lau

Mechanical Engineering

Statement of Confidentiality: The complete senior project report was submitted to the project advisor and sponsor. The results of this project are of a confidential nature and will not be published at this time.

Mechanical Characterization Of Selectively Laser Melted 316l Stainless Steel Body Centered Cubic Unit Cells And Lattice Of Varying Node Radii And Strut Angle, Christopher James Hornbeak

Master's Theses

An experimental study of several variants of radius and strut angle of the body centered cubic unit cell was performed to determine the mechanical properties and failure mechanisms of the mesostructure. Quasi static compression tests were performed on an Instron® universal testing machine with a 50kN load cell at 0.2mm/min. The test samples were built using a SLM Solutions 125 selective laser melting machine with 316L stainless steel. Test specimens were based on 5mm cubic unit cells, with a strut diameter 10% of the unit cell size, with skins on top and bottom to provide a cantilever boundary constraint. Specimens …

Voltage-Controlled Deposition Of Nanoparticles For Next Generation Electronic Materials, Subhodip Maulik

LSU Doctoral Dissertations

This work presents both a feasibility study and an investigation into the voltage-controlled spray deposition of different nanoparticles, namely, carbon nanotubes (CNTs), as well as molybdenum disulfide (MoS₂) and tungsten disulfide (WS₂) from the transition metal dichalcogenides (TMDCs) family of materials. The study considers five different types of substrates as per their potential application to next-generation device electronics. The substrates selected for this research were: 1) aluminum as a conducting substrate, 2) silicon as a semiconducting substrate, 3) glass, silicon dioxide (SiO₂), and syndiotactic poly methyl methacrylate (syndiotactic PMMA) as insulating substrates.

Since the …

Surface Area And Electrocatalytic Properties Of Feni Nanoparticles For The Oxygen Evolution Reaction (Oer), James Burrow

Chemical Engineering Undergraduate Honors Theses

Iron-nickel bimetallic electrocatalysts have recently emerged as some of the best candidates for the oxygen evolution reaction (OER) in alkaline electrolyte. Understanding the effects of composition and morphology of iron-nickel nanoparticles is crucial for optimization and enhanced electrocatalyst performance. Both physical surface area and electrochemical surface area (ECSA) are functions of morphology. In this study, four different iron-nickel nanoparticle catalysts were synthesized. The catalysts were varied based on morphology (alloy versus core-shell) and composition (low, medium, and high stabilizer concentration). Brunauer-Emmett-Teller (BET) surface area analysis was conducted on three of the synthesized iron-nickel nanoparticles using a physisorption analyzer while electrochemical …

Optically Active Dye-Based Systems Templated By Dna Exhibiting Excitonic Delocalization, Brittany Lynn Cannon

Boise State University Theses and Dissertations

The concept of quantum computing was first developed in the early 1980’s. The attraction of quantum computers is their potential capacity to solve extremely complex problems, such as factorization, on a timescale far faster than that of classical computers. However, realization of quantum computation is currently in its infancy, and recent implementations possess serious drawbacks that reduce their appeal. Some challenges of current designs include the necessity to cool the systems using liquid helium to near absolute zero temperatures (15 mK) in order to maintain sufficiently long-lifetimes of the Qbits (i.e., unit of quantum information), difficulty with scaling up the …

Development Of Nanostructures By Atomic And Molecular Layer Deposition, Andrew P. Lushington

Electronic Thesis and Dissertation Repository

Atomic layer deposition (ALD) is a thin film deposition technique that has a rich history of being an enabling technique. This vapor phase deposition process can produce a variety of thin films and nanostructures. ALD is based on sequential, self-limiting reactions and provides angstrom level control over film growth. Furthermore, ALD allows for conformal deposition on high-aspect ratio structures and can provide tunable film composition. As nanotechnology marches forward, the development of nanomaterials has significantly advanced. Additional functionality can be imparted to nanomaterials by using surface modification techniques. Given the advantages of ALD, this technique has become a powerful tool …

Evolution Of Mg Az31 Twin Activation With Strain: A Machine Learning Study, Andrew D. Orme

Undergraduate Honors Theses

Machine learning is being adopted in various areas of materials science to both create predictive models and to uncover correlations which reveal underlying physics. However, these two aims are often at odds with each other since the resultant predictive models generally become so complex that they can essentially be described as a black box, making them difficult to understand. In this study, complex relationships between microstructure and twin formation in AZ31 magnesium are investigated as a function of increasing strain. Supervised machine learning is employed, in the form of J-48 decision trees. In one approach, strain is incorporated as an …

Waste Management By Waste: Removal Of Acid Dyes From Wastewaters Of Textile Coloration Using Fish Scales, S M Fijul Kabir

LSU Master's Theses

Removal of hazardous acid dyes by economical process using low-cost bio-sorbents from wool industry wastewaters is of a pressing need, since it causes skin and respiratory diseases and disrupts other environmental components. Fish scales (FS), a by-product of fish industry, a type of solid waste, are usually discarded carelessly resulting in pungent odor and environmental burden. In this research, the FS of black drum (Pogonias cromis) were used for the removal of acid dyes (acid red 1 (AR1), acid blue 45 (AB45) and acid yellow 127 (AY126)) from wool industry wastewaters by absorption process with a view to …

Fabrication And Applications Of Printed And Handwriting Electronics, Tengyuan Zhang

Electronic Thesis and Dissertation Repository

The accelerating arrival of the Internet of Things (IoT) era creates a rapidly growing demand for printed electronic. As a low-cost and green substrate, cellulose paper has become the most attractive choice for the printing of sustainable and disposable electronics. However, manufacture of high quality circuits with high conductivity on cellulose paper remains a challenge due to the substrate’s high porosity and roughness. In this thesis, a method for facile fabrication of hybrid copper-fiber highly conductive features on low-cost cellulose paper with strong adhesion and enhanced bending durability is introduced. With three-dimensional electroless deposition (ELD) of copper, the as-fabricated circuits …

Modeling Deformation Behavior And Strength Characteristics Of Sand-Silt Mixtures: A Micromechanical Approach, Mehrashk Meidani

Doctoral Dissertations

This dissertation is comprised of six chapters. In the first chapter the motivation of this research, which was modeling the deformation behavior and strength characteristics of soils under internal erosion, is briefly explained. In the second chapter a micromechanis-based stress-strain model developed for prediction of sand-silt mixtures behavior is presented. The components of the micromechanics-based model are described and undrained behavior of six different types of sand-silt mixtures is predicted for several samples with different fines contents. The need for a more comprehensive compression model for sand-silt mixtures is identified at the end of this chapter. This desired compression model …

Processing Of Cubic Stabilized Zirconia Electrolyte Membranes For Electrolyte-Supported Single Cell Solid Oxide Fuel Cells Using Tape Casting, Arturo Coronado Rodriguez

Honors Undergraduate Theses

Electrochemical conversion devices are a developing technology that prove to be a viable and more efficient alternative to current environmentally friendly generation devices. As such, constant research has been done in the last few decades to increase their applications and reliability. One of these systems, and the focus of this research, is the single cell Solid Oxide Fuel Cell (SOFC). These systems are a developing technology which main caveat is the need of high operating temperatures and costs. As such, most multidisciplinary research has been focused on researching materials and/or processes that help mitigate the costs or lower the operating …