Other Materials Science and Engineering Commons^™

Investigation Of A Method To Determine Mechanical Properties Of Integral Composite Hinges For Application In Foldable Skis, Jada Evers, Kathryn Johnson

Materials Engineering

No abstract provided.

Mitigation Of Corrosion Under Insulation (Cui) Of Carbon Steel Of Different Insulating Materials: A Literature Review And Testing Analysis, Michael Alexander Lowes

Materials Engineering

Equipment often found in refineries may be enveloped in insulation and weathering jackets to maintain internal processing temperatures. In many cases moisture from the environment will penetrate the weathering jacket and infiltrate the insulation, leaching corrosive ions to the surface of metal equipment, effectively creating a corrosion cell. The goal of this project is to investigate different insulating materials for their ability to inhibit corrosion under insulation (CUI). The inhibiting mechanism utilizes water ingress that leaches ions from the insulator to bond with the surface metal and create a passive layer, inhibiting any further corrosion. This study will follow ASTM …

Invariant-Based Method For Improving Efficiency Of Mechanical Testing In Aerospace Certification Of Carbon Fiber-Epoxy Composites, Alyssa Rina Gruezo, Erika Gabrielle Hansen

Materials Engineering

The current challenge with qualification of carbon fiber composites in the aerospace industry would be the low efficiency of testing hundreds of samples. The Trace Theory strives to streamline the qualification process by utilizing a material’s Trace to predict properties of composites using Excel programs and basis data. To test this theory, predicted properties from the program, QuickLam, were compared to experimental data. Unidirectional 0° (T1), unidirectional 90° (T2), quasi-isotropic (T3), and hard quasi-isotropic (T4) laminates were made using HexTowR carbon fiber and TC250 resin provided by TenCate Advanced Composites. Tensile and compression tests were done according to ASTM D3039 …

An Experimental And Numerical Study Of Nanomechanical Behavior Of Hard/Soft Multilayered Coatings, Benigno Sandoval

Mechanical Engineering ETDs

Multilayer thin film composites, sometimes referred to as nanolaminates, have emerged as an important subset of materials with novel, and often tunable, properties such as high strength, high toughness, and resistance to wear or corrosion. Often fabricated using alternating layers of two or more materials, these multilayer thin film coatings are typically expensive and time intensive to fabricate and characterize and exhibit novel responses to nanomechanical testing such as plasticity during unloading. This thesis explores the nanoindentation response of hard/soft multilayer coatings through examination of the optical coating Al/SiC and similar coating Al/SiO2. Instrumented indentation was used to study single …

Development And Degradation Analysis Of Novel Micro And Nanostructured Transition Metal Oxide (Tmo) Anodes For Aqueous Sodium Ion Batteries., Santanu Mukherjee

Electronic Theses and Dissertations

One of the primary motivations driving battery technology research is the need to develop cleaner and more efficient energy storage systems. The portable electronics industry has developed exponentially, especially over the last couple of decades and therefore the importance of efficient electrochemical energy storage systems cannot be overstated. Li-ion batteries have been the predominant rechargeable energy in use, however, they have their own particular drawbacks viz. flammability of the electrolyte, expensive mining of the Li metal etc. This is where the importance of Na-ion batteries lie. This research focuses on using existing transition metal oxides (TMOs) and tuning their crystal …

Data Driven Discovery Of Materials Properties., Fadoua Khmaissia

Electronic Theses and Dissertations

The high pace of nowadays industrial evolution is creating an urgent need to design new cost efficient materials that can satisfy both current and future demands. However, with the increase of structural and functional complexity of materials, the ability to rationally design new materials with a precise set of properties has become increasingly challenging. This basic observation has triggered the idea of applying machine learning techniques in the field, which was further encouraged by the launch of the Materials Genome Initiative (MGI) by the US government since 2011. In this work, we present a novel approach to apply machine learning …

Peridynamic Models For Fatigue And Fracture In Isotropic And In Polycrystalline Materials, Guanfeng Zhang

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

To improve design and reliability, extensive efforts has been devoted to understanding damage and failure of materials and structures using numerical simulation, as a complement of theory and experiment. In this thesis, peridynamics is adopted to study fatigue and dynamic failure problems.

Fatigue is a major failure mode in engineering structures. Predicting fracture/failure under cyclic loading is a challenging problem. Classical model cannot directly be applied to problems with discontinuities. A peridynamic model is adopted in this work because of important advantages of peridynamics in allowing autonomous crack initiation and propagation. A recently proposed peridynamic fatigue crack model is considered …

Technical Feasibility Of Selectively Separating Rare Earth Elements By Vapor Phase Extraction And Condensation, Katie Lyons

Graduate Theses & Non-Theses

Experiments were performed to evaluate the technical feasibility of selectively separating selected rare earth halides (bromides and chlorides) using a volatilization and condensation technique. Initially, optimum chloridizing and bromidizing roast parameters were secured in studies performed on reagent grade rare earth oxide samples and subsequently confirmed in tests performed on mineral ore and concentrate samples. The volatilization and condensation experiments were performed by placing the subject rare earth halide samples in an argon-purged multiple-zone tube furnace wherein the temperature profile was controlled to establish separate vaporization and condensation regions. Following each experiment, condensate and solid residue samples were analyzed to …

Analysis Of Additively Manufactured Lattice Structures Using Finite Element Methods, Christopher A. Box

Theses and Dissertations

Additive Manufacturing (AM) processes are well known for their ability to fabricate parts with complex geometries. Lattice structures leverage this ability to create parts with high strength-to-weight ratio and other desirable structural qualities. This research presents a parameterized modeling tool using common Finite Element Analysis (FEA) and scripting software with which aggregated lattice structures can be analyzed, given different geometric properties and loading conditions. A full factorial Design of Experiments is run to explore the effects of various parameters on the strength of lattice structures. Experimental compressive strength results from three FDM-produced PLA lattices are discussed and compared to predictions …

Redesign Of Computer Keyboards For Hospital And Consumer Use, Kent Williams, Brian Jensen, Anton Bowden

Biomedical Engineering Western Regional Conference

Application of carbon nanotube coatings to computer keyboards in order to reduce the spread of bacteria in hospitals and homes.

Keywords: carbon nanotube, bacteria, antimicrobial, keyboard, design, MRSA, biofilm

The Effect Of Biocomposite Material In A Composite Structure Under Compression Loading, Benjamin Andrew Sweeney

Master's Theses

While composite structures exhibit exceptional strength and weight saving possibilities for engineering applications, sometimes their overall cost and/or material performance can limit their usage when compared to conventional structural materials. Meanwhile ‘biocomposites’, composite structures consisting of natural fibers (i.e. bamboo fibers), display higher cost efficiency and unique structural benefits such as ‘sustainability’. This analysis will determine if the integration of these two different types of composites are beneficial to the overall structure. Specifically, the structure will consist of a one internal bamboo veneer biocomposite ply; and two external carbon fiber weave composite plies surrounding the bamboo biocomposite. To acquire results …

Effect Of Liquid Contamination On Hermeticity And Seal Strength Of Flexible Pouches With Lldpe, Francesca Delle Cese, Koushik Saha, S. Roy, Jay Singh

Journal of Applied Packaging Research

Flexible packaging is a growing successful market and the majority of flexible package applications are for the food industry. The demand for process optimization and reduced production costs, has led to an increase in flexible packaging. However, fast production lines can result in contamination in the seal area. For flexible food packaging, contamination is considered any food particle or substance trapped in the seal area. Current quality control processes can detect contamination in the seal area, but it is not determined if seal contamination affects seal quality. Oil-based and sodium based snack foods are two common categories that can be …

Composite Cold Expansion Tooling, Andrew Amos

All Undergraduate Projects

In the world of aircraft manufacturing, cold expansion products literally hold these aircraft together. The problem faced today is that the Little Brute Hydraulic Puller designed and built by Fatigue Technology Inc. is a handheld steel hydraulic cylinder that is heavy and expensive to produce. In a market that demands continuous improvement, there is a constant push to make the product cheaper, better and lighter. In order to accomplish this demand a composite tube will be substituted in the design as the primary pressure cylinder instead of the traditional steel pressure cylinder in order to create a lighter and cheaper …

A Simple Embedded Atom Potential For Palladium-Hydride, Yang Zhang

Theses, Dissertations and Capstones

Metal Hydride systems are an important research topic in material science because of their many practical, industrial, and scientific applications. Therefore, the development of reliable and efficient interatomic potentials for metal hydrides systems, to be utilized in atomistic modeling, can be of great value in accelerating the research in this field. The embedded-atom method (EAM), based on the density functional theory (DFT), has the advantage of being both computationally efficient and being well suited for modeling metal hydride systems. In this work, the author has developed an efficient EAM potential for the palladium hydride (Pd-H) alloy system. Contrary to previously …

Computational Modeling Of Percolation Conduction And Diffusion Of Heterogeneous Materials, Jian Qiu

Electronic Theses and Dissertations

Heterogeneous materials provide a unique combination of desirable mechanical, thermal or electrical properties. This dissertation presents several micro-structure modeling approaches to predict the effective properties of heterogeneous materials and demonstrates its certain application toward two highly heterogeneous, unconventional structural composite materials (carbon fiber reinforced composite materials and graphene nanoplatelets composite). By using the efficient computational algorithm based on the FEA, a randomly oriented disk-shaped particles system are generated. A new element partition scheme based on the vector operations and geometry of inclusion has been implemented to mesh the intersected disks. The computed equivalent conductivity is expressed as a power-law function …

A Study Of Copper And Aluminum Incorporated Chromium Oxide Core-Shell Magnetic Nanoparticles, Tamzid Ibn Minhaj

Graduate Theses/Dissertations

The structural and magnetic properties of copper (Cu) and aluminum (Al) -incorporated chromium oxide (α-Cr₂O₃, i.e., chromia) inverted core-shell nanoparticles (CSNs) were investigated. The objectives of this study were to determine the role of the substituting (for chromium, Cr) element and of Cu concentration on governing the magnetic properties of the CSNs. For synthesis of the CSNs, α-Cr₂O₃ nanoparticles were first grown using microwave assisted synthesis whereupon a hydrothermal nanophase epitaxy (HNE) method was used to incorporate Cu or Al in the chromia-based shell of the nanoparticles. The morphology, structure and size characteristics …

Study Of Multiferroic Properties Of Ferroelectric- Ferromagnetic Heterostructures Bzt-Bct/Lsmo, Md Abdullah-Al Mamun

Graduate Theses/Dissertations

Currently, there has been a flurry of research focused on multiferroic materials due to their potential applications. Lead (Pb)-based ferroelectric and multiferroic materials (PZT, PMN-PT, PZN-PT etc.) have been widely used for sensors, actuators, and electro-mechanical applications due to their excellent dielectric and piezoelectric properties. However, these materials are facing global restriction due to the toxicity of Pb. In this thesis, multiferroic properties of ferroelectric-ferromagnetic heterostructures consist of Pb-free perovskite oxides 0.5Ba(Zr_0.2Ti_0.8)O₃-0.5 (Ba_0.7 Ca_0.3)TiO₃ (BZT-BCT) and La_0.7Sr_0.3MnO₃ (LSMO) have been studied. The heterostructures BZT-BCT/LSMO were …

Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li

Dissertations, Master's Theses and Master's Reports

Electric field-induced antiferroelectric(AFE)/paraelectric(PE)-to-ferroelectric(FE) phase transitions are investigated for the associated nonlinear dielectric behavior, which could offer high dielectric capacity. The phenomenon in monolithic materials has been computed for Kittel antiferroelectric and BaTiO₃ model systems using the Landau-Ginzburg-Devonshire theory. The general switching curves give values of the polarization as a function of external electric field. A similar computation is performed for particle-filled polymer-matrix composites where an internal depolarization field is considered. The polarization-electric field response changes with different depolarization factors, which demonstrate the shape and alignment of the dielectric particles embedded in polymer-matrix are key factors for the composite to …

The Effects Of Carboxylic Acids In Aluminum Anodizing, Abby E. Koczera

Honors Theses and Capstones

Hard-anodized alumina coatings were formed in sulfuric acid at low temperature and high current density in the presence of carboxylic acid additives. Citric acid, trimesic acid, mellitic acid and ethylenediaminetetraacetic acid (EDTA) were utilized in varying concentrations. The additives were chosen for their capacity to form complexes with tri-valent aluminum and hence impart chemical stability to the coatings. The coatings were sealed in boiling water, and corrosion resistance was observed in a high pH solution of potassium hydroxide. The coatings were examined using scanning electron microscopy (SEM) to assess coating thickness and pore dimensions. Thicker coatings were produced when the …

Polyvinyl Alcohol (Pva) Fiber-Reinforced Rubber Concrete And Rubberized Self-Compacting Concrete, Jiaqing Wang

Dissertations, Master's Theses and Master's Reports

This study experimentally investigates the mechanical performance and durability of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete and the rubberized self-compacting concrete. The waste rubber particles were introduced as a partial replacement of fine aggregate in the plain concrete. In addition, the waste tire rubbers were pre-treated with alkali surface treatment method to enhance the performance. The PVA fibers were added to the concrete mixes to enhance the post-failure resistance and thus fracture energy. Rubberized fiber concrete samples were prepared with different fine aggregate replacement ratios and the optimum fiber content. At the same time, the rubber particles had been used …