Other Materials Science and Engineering Commons^™

An Evaluation Of Induction Heating In Healthcare Food Industry, Barrett Alexander Hampton

Masters Theses & Specialist Projects

This thesis addresses the problem healthcare facilities are having in maintaining proper food temperatures while transporting meals to patients after food has left the kitchen area. Induction heat has been a known method for generating heat for many years. The commercial food industry currently uses this technology, which is beginning to appear in the residential sector as well because of developments made by manufacturers. This study focuses on the top commercial brand models of induction heaters and the supporting materials currently used to create heat sources to maintain food temperatures in hospitals and long term care facilities.

The research in …

Optimal Sintering Temperature Of Ceria-Doped Scandia Stabilized Zirconia For Use In Solid Oxide Fuel Cells, Amanda K. Assuncao

Honors Undergraduate Theses

Carbon emissions are known to cause decay of the Ozone layer in addition to creating pollutant, poisonous air. This has become a growing concern among scientists and engineers across the globe; if this issue is not addressed, it is likely that the Earth will suffer catastrophic consequences. One of the main culprits of these harmful carbon emissions is fuel combustion. Between vehicles, power plants, airplanes, and ships, the world consumes an extraordinary amount of oil and fuel which all contributes to the emissions problem. Therefore, it is crucial to develop alternative energy sources that minimize the impact on the environment. …

Design Of Shape-Conforming Nosecone For Optimal Fluid Flow From Transonic To Supersonic Range, Anna Tombazzi

Williams Honors College, Honors Research Projects

Modern flight vehicles, such as rockets, missiles, and airplanes, experience a force caused by forebody wave drag during the flight. This drag force is induced when the frontal point of each vehicle breaks the pressure wave during flight. Efforts to reduce this wave drag force to improve flight efficiency include modifying the nosecone profile of the flight vehicles to lower the drag force.

This project revolved around creating a design to make the transformation of nosecone shapes from a ¾ Parabolic profile to a ½ Power Series profile possible, mid-flight. Using a novel nosecone assembly, shape memory alloys (SMAs) and …

Design, Analysis, And Application Of A Cellular Material/Structure Model For Metal Based Additive Manufacturing Process., Shanshan Zhang

Electronic Theses and Dissertations

Powder bed fusion additive manufacturing (PBF-AM) has been broadly utilized to fabricate lightweight cellular structures, which have promising potentials in many engineering applications such as biomedical prosthesis, aerospace, and architectural structures due to their high performance-to-weight ratios and unique property tailorabilities. To date, there is still a lack of adequate understanding of how the cellular materials are influenced by both the geometry designs and process parameters, which significantly hinders the effective design of cellular structures fabricated by PBF-AM for critical applications. This study aims to demonstrate a cellular structure design methodology that integrates geometrical design and process-material property designs. Utilizing …

Investigating Scalable Manufacturing Of High-Conductivity Wires And Coatings From Ultra-Long Carbon Nanotubes, Pouria Khanbolouki

Mechanical Engineering ETDs

Carbon nanotubes (CNTs) are a promising candidate for next generation of electrical wirings and electromagnetic interference (EMI) shielding materials due to their exceptional mechanical and electrical properties. Wires and coatings from ultralong nanotubes that are highly crystalline, well-aligned and densely packed can achieve this goal. High-performance CNT conductors will be relatively lightweight and resistant to harsh conditions and therefore can potentially replace current conductors in many industries including aerospace, automotive, gas and oil.

This thesis investigates a new manufacturing approach, based on conventional solution coating and wire drawing methods, to fabricate high conductivity wires and coatings from ultra-long carbon nanotubes. …

Simulating Dynamic Failure Of Polymer-Bonded Explosives Under Periodic Excitation, Rachel Kohler, Camilo Duarte Cordon, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

Accidental mishandling of explosive materials leads to thousands of injuries in the US every year. Understanding the mechanisms behind the detonation process is crucial to prevent such accidents. In polymer-bonded explosives (PBX), high-frequency mechanical excitation generates thermal energy and can lead to an increase in temperature and vapor pressure, and potentially the initiation of the detonation process. However, the mechanisms behind this energy release, such as the effects of dynamic fracture and friction, are not well understood. Experimental data is difficult to collect due to the different time scales of reactions and vibrations, so research is aided by running simulations …

A Study In The Use Of Elastic Materials In Expandable Containment Units, Andrew J. Eisenman, Joby Anthony Iii, David Satagaj

Montview Journal of Research & Scholarship

The rigidity of materials in conjunction with the aspect of elasticity has been a concern of modern technologies and construction in recent centuries because of the advantages that expandable storage would bring to the fields of containment units with respect to population growth and space exploration. The world population is currently growing at an exponential rate, and as our population grows, the more important it will become to have containment units that can both contain large volumes of material as well as minuscule amounts of material without wasting space. In order accomplish this, we will need a new type of …

Effect Of Composition And Build Direction On Additively Manufactured Hastelloy X Alloys, Justin A. Spitzer, Jeffrey T. Schloetter, Sarah Zerga

Materials Engineering

Microcracking has caused premature failure and reduction in properties in additively manufactured (AM) Hastelloy X. The purpose of this research is to meet or exceed the mechanical properties of wrought Hastelloy X by modifying the composition and build direction of Hastelloy X manufactured using Direct Metal Deposition (DMD). Tensile testing, scanning electron microscopy (SEM), and metallography were performed on the samples. ANOVA was used to analyze the dependence that the properties had on build direction and composition. The nominal composition wrought samples had a yield strength of 310.1 MPa and a 60.79% Elongation. Alloy P60-X18 in a horizontal build had …

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 …

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 …

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 …

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 …

Study On Criterion Of Fabricating Columnar Dendrite Structure Dz466 Superalloy Based On Lmc Process, Xun Sun

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

The Influence Of Welding Parameters On Initial Instability Dynamics During Solidification, Fengyi Yu, Yanhong Wei, Xiaohong Zhan

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Prediction Of The Graphite Morphology And Nodularity Based On The Quantitative Sample Solidification Cooling Curves, Han Ye, Chao Li, Qingyou Han, Xiangjie Yang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Temperature Filed Numerical Simulation Of Laser Welding For Ta15 Titanium Alloy By Coupling Thermal And Phase Transformation, Wenmin Ou, Yanhong Wei, Xiaohong Zhan, Gaoyang Mi

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Simulation On The Sealing Of Aluminum Ball Joint, Haobin Tian, Xiaohang Liu, Xuelei Li, Jun Feng

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Modeling And Simulation Of Dendrite And Porosity Evolution During Solidification In The Molten Pool Of Al–Cu Alloys, Cheng Gu, Yanhong Wei, Xiaohong Zhan

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Fe Simulation For Accuracy Evolution And Control In Hot Forging Of Non-Circular Spur Bevel Gear, Wuhao Zhuang, Xinghui Han

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

High Strain Rate Experiments Of Energetic Material Binder, Roberto Rangel Mendoza, Michael Harr, Weinong Chen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Energetic materials, in particular HMX, is widely used in many applications as polymer bonded explosives (PBX) and rocket propellant. However, when damaged, HMX is known to be an unstable substance which renders it a hazardous material and in some cases unreliable. Finding critical mechanical conditions at high rates that render various forms of energetic materials as unreliable would be vital to understand the effects that vibrations and compression forces have on energetic materials. A better understanding would enable the ability to develop improvements in the manufacturing of PBX and rocker propellant. The method utilized to evaluate the mechanical properties of …

Metals Additive Manufacturing Powder Aging Characterization, Thomas Russell Lovejoy, Nicholas Karl Muetterties, David Takeo Otsu

Mechanical Engineering

The metallic additive manufacturing process known as selective laser melting requires highly spherical, normally distributed powder with diameters in the range of 10 to 50 microns. Previous observations have shown a degradation in powder quality over time, resulting in unwanted characteristics in the final printed parts. 21-6-9 stainless steel powder was used to fabricate test parts, with leftover powder recycled back into the machine. Powder samples and test specimens were characterized to observe changes across build cycles. Few changes were observed in the physical and mechanical properties of the specimens, however, there were indications of chemical changes across cycles. Potential …

Multi-Use Fireline Handtool, Bruce W. Bernard Jr

All Undergraduate Projects

A wildland firefighter is a valuable resource to protecting public lands and managing fuels. The many hand tools used by firefighters aid in their ability to complete any required tasks effectively. Several of the tools available are specially purposed for individually grubbing, scraping, or liming. A small squad of firefighters could become a more effective resource if the tools they carried could perform several of these purposes as one single tool. To improve the effectiveness of an individual on the fireline a multi-use hand tool was designed to include an axe for liming and a heavy duty scraper for grubbing …

Mechanical Testing Of Fused Filament 3-D Printed Components For Distributed Manufacturing, Nagendra Gautam Tanikella

Dissertations, Master's Theses and Master's Reports

Fused filament fabrication (FFF)-based open-source 3-D printers offer the potential of decentralized manufacturing both in developing and developed countries. Unfortunately, a severe lack of data and standards relating to material properties and printed components limit this potential. This thesis first investigates the mechanical properties of a wide-range of FFF materials and provides a database of mechanical strength of the materials tested. The results demonstrate that the tensile strength of a 3-D printed specimen depends largely on the mass of the specimen, which provides a means to estimate the strength of 3-D printed components. Then this information is used to evaluate …

Three-Dimensional Microstructural Effects On Multi-Site Fatigue Crack Nucleation Behaviors Of High Strength Aluminum Alloys, Yan Jin

Theses and Dissertations--Chemical and Materials Engineering

An experimental method was further developed to quantify the anisotropy of multi-site fatigue crack initiation behaviors in high strength Al alloys by four-point bend fatigue testing under stress control. In this method, fatigue crack initiation sites (fatigue weak-links, FWLs) were measured on the sample surface at different cyclic stress levels. The FWL density in an alloy could be best described using a three-parameter Weibull function of stress, though other types of sigmoidal functions might also be used to quantify the relationship between FWL density and stress. The strength distribution of the FWLs was derived from the Weibull function determined by …

Effects Of Magnetic Field On The Shape Memory Behavior Of Single And Polycrystalline Magnetic Shape Memory Alloys, Ali S. Turabi

Theses and Dissertations--Mechanical and Aerospace Engineering

Magnetic Shape Memory Alloys (MSMAs) have the unique ability to change their shape within a magnetic field, or in the presence of stress and a change in temperature. MSMAs have been widely investigated in the past decade due to their ability to demonstrate large magnetic field induced strain and higher frequency response than conventional shape memory alloys (SMAs). NiMn-based alloys are the workhorse of metamagnetic shape memory alloys since they are able to exhibit magnetic field induced phase transformation. In these alloys, martensite and austenite phases have different magnetization behavior, such as the parent phase can be ferromagnetic and martensite …

Shape Memory Behavior Of Single Crystal And Polycrystalline Ni-Rich Nitihf High Temperature Shape Memory Alloys, Sayed M. Saghaian

Theses and Dissertations--Mechanical and Aerospace Engineering

NiTiHf shape memory alloys have been receiving considerable attention for high temperature and high strength applications since they could have transformation temperatures above 100 °C, shape memory effect under high stress (above 500 MPa) and superelasticity at high temperatures. Moreover, their shape memory properties can be tailored by microstructural engineering. However, NiTiHf alloys have some drawbacks such as low ductility and high work hardening in stress induced martensite transformation region. In order to overcome these limitations, studies have been focused on microstructural engineering by aging, alloying and processing.

Shape memory properties and microstructure of four Ni-rich NiTiHf alloys (Ni50.3Ti29.7Hf20, Ni50.7Ti29.3Hf20, …

Nanoindentation Of A Zinc Metal Soap Mixture For Use In A Laser Printer, George A. Nimick

Theses and Dissertations--Chemical and Materials Engineering

At the start of this project, the possible choices of metal soaps had already been narrowed to include some of the zinc soaps used in this project. These zinc soaps are mixtures of zinc stearate and zinc palmitate of varying ratios purchased from a supplier. Zinc soap was chosen as result of its common use in various industries as a lubricant and mold release, which implied potential benefits in an electrophotographic printing system. These potential benefits include, but are not limited to, a more efficient transfer from a photoconductive drum and protection of the drum from mechanical and chemical degradation. …

A Study To Evaluate Non-Uniform Phase Maps In Shape Memory Alloys Using Finite Element Method, Naren Motte

Theses and Dissertations

The unique thermo-mechanical behavior of Shape Memory Alloys (SMAs), such as their ability to recover the original shape upon heating or being able to tolerate large deformations without undergoing plastic transformations, makes them a good choice for actuators.

This work studies their application in the aerospace and defense industries where SMA components can serve as release mechanisms for gates of enclosures that have to be deployed remotely. This work provides a novel approach in evaluating the stress and heat induced change of phase in a SMA, in terms of the transformation strain tensor. In particular, the FEA tool

ANSYS has …