Materials Science and Engineering Commons^™

Effects Of Abrasive Particles On The Projected Fatigue Life Of Nylon Climbing Rope, Casey Johnson, Charlie Klonowski

Materials Engineering

When climbing rope is used outdoors, it is exposed to foreign particles such as sand and silt. These particles can potentially work their way through a rope’s sheath and damage the load bearing core decreasing the rope’s strength without exhibiting obvious wear. This project quantified the effect of abrasive particles on the fatigue life of nylon climbing rope. The experimental design involved 18 pieces of static nylon rope of kernmantle construction. 9 of these samples were heavy agitated in a slurry of water, silt, sand and soil, and left to sit for 24 hours. The remaining 9 samples were submerged …

Synthesis Of White Cadmium-Selenium Quantum Dots, Kyle Reilly

Materials Engineering

A process was developed for the synthesis of cadmium-selenium quantum dots that fluoresce at multiple wavelengths, giving a white color to the solution. The process involved making a selenium pre-cursor, then a cadmium precursor, then injecting the selenium precursor into the cadmium precursor and extracting a sample. Once the a repeatable process for synthesizing white quantum dots was developed, the absorption and fluorescence was measured and recorded over a period of two weeks. In the development of the process, the key variables were the temperature of the cadmium precursor and the time between injecting the selenium precursor and extracting the …

Characterization Of Positive Macrosegregation At The Subsurface Of Direct-Chill Cast 7050 Aluminum Forging Billets, Aaron Youril

Materials Engineering

Segregation of alloying elements during casting of forging billets may persist to the final forged component leading to unacceptable surface appearance. Determination of the elements or compounds that segregate is the essential first step to solving this problem. Differential Scanning Calorimetry (DSC) was used to determine a composition profile of the macrosegregation occurring at the subsurface of an as-cast 7050 aluminum alloy billet. Data collection was carried out by separating 10 to 20 mg samples from the outer centimeter along the radius of the billet, as well as samples from the bulk interior of the billet for comparison with the …

Analysis Of Failed Forging Saddling Mandrels And Process Improvements For Increased Mandrel Lifespan, Brock Costalupes

Materials Engineering

This project seeks to increase the lifespan of steel mandrels used by Schlosser Forge in the saddling process, which is part of the production of forged rings for the aerospace and power generation industries. All saddle mandrel samples were taken from used 4340 steel mandrels. Hardness profiles were measured across rectangular bars cut from the transverse direction of a completely fractured piece of a 7″ diameter mandrel. The hardness near one outer surface of the tested bar was 36 HRC and gradually decreased to 30.5 HRC at the opposite surface. Macroscopic examination of the primary fracture surface along with light …

Effect Of Heating Temperature, Heating Time And Initial Microstructure On Recrystallization Of Waspaloy During Heating For Forging, Marissa Hill

Materials Engineering

A fine, uniform grain size is required for creep limited Waspaloy in aircraft engine applications. Upon heating, Waspaloy does not always recrystallize in a uniform manner resulting in occasional large grains with a majority of the grains meeting the grain size requirements. Waspaloy’s microstructure was analyzed with different heat treatments and in the as-forged condition. The strengthening mechanism is the gamma prime phase. The gamma prime solvus temperature is 1908°F so the different heat treatments were determined around that temperature, as well as the forging temperature range of 1800-2150°F. At the 1850°F heat treatment, the microstructure recrystallized with small grains, …

The Incorporation Of Electrohydrodynamics And Other Modifications Into A Dry Spinning Model To Develop A Theoretical Framework For Electrospinning, Yuki Imura

Dissertations

The objective of this research was the development of a mathematical model of the electrospinning process using dry spinning modeling principles as a basis. This model is directed at the identification of parameters which influence final fiber characteristics, e.g., solvent concentration, temperature, spin line tension, and electric field. Preliminary computer simulations were performed; however, the generated data was inconclusive and was determined to be due in part to the complexity of the modeled system and the subsequent computational difficulties encountered. Although a comprehensive computational model of the electrospinning process has not yet been demonstrated, the theoretical development that was undertaken …

Synthesis, Molecular And Solid State Structures, And Magnetic Properties Of Sandwich Lanthanide Phthalocyanines Lacking C-H Bonds, Wycliffe A. Graham

Dissertations

A new class of sandwich phthalocyanine (Pc) compounds without C-H bonds was synthesized and characterized. They are the bis[octakis(perfluoro i-C₃F₇) octakis(perfluoro)phthalocyaninato(2−)]M(III) complexes, formulated as (F₆₄Pc)₂MH, M = Tb, Dy, Lu, Y. Single molecular magnetic (SMM) behavior in the (F₆₄Pc)₂TbH and (F₆₄Pc)₂DyH complexes was confirmed through slowed relaxation response of their magnetization in an applied time varying magnetic field during alternating current (AC) magnetic testing in the range 2 - 50 K. The energy barrier to magnetic reversal, Δ = 215 cm^-1 and …

Rational Design Of Hydrogen-Free Catalytic Active Sites, Andrei Ioan Loas

Dissertations

Materials that are organic-based and exhibit oxidative catalytic activity, including free-radical pathways, while being refractory to the activated oxygen species are not known. The synthesis of several classes of such materials, their electronic and structural characterizations as well as catalytic properties are reported. Their rational molecular design and biologically inspired reactivity are based on enzymatic active sites, which are reengineered into robust metal-organic fluoroalkylated scaffolds that, for the first time, exhibit structural asymmetry and tunable π-π interactions both in solution and solid state. In these complexes, labile C-H bonds are replaced with chemically and thermally resistant C-F bonds to create …

Inkjet Printing Of Resistive-Type Humidity Sensor For Harsh Environments, Hamed Kazerani

Dissertations

A flexible resistive-type humidity sensor for harsh environments is successfully designed and fabricated by an inkjet printing method using a Dimatix materials printer (DMP-2800 series from Fujifilm). Construction of the sensors is based on inkjet printed interdigitated silver electrodes on a polyimide flexible substrate along with an inkjet printable polyaniline (PANi) as humidity sensitive material. A copolymer of ethylene and vinyl alcohol (EVOH) is used as sensor protective coating. Double strand water- soluble PANi ink is synthesized by polymerization of aniline monomers with poly(4- styrenesulfonic acid) (PSSA) as a template.

Manufactured devices showed high sensitivity (/% @ 45%RH) to humidity …

Magnetic Targeted Drug Delivery System In Gene Therapy, Weilong Lu

Theses

Drug delivery system is a method to transport the drug of the required amount accurately to the targeted diseased part. Recently, the concept of Magnetic Targeted Drug Delivery System (MTDDS), based upon magnetic particles under the action of an external magnetic field, exhibits considerable potential for a wide range of medical applications. Gene therapy is the insertion of genes into an individual's cells and tissues to treat diseases. As the recombinant virus vector has many limits and problems, more studies turn to the nonvirus vectors, which have transfection efficiency and low cytotoxicity. PLLA(poly(L lactic acid)) can be biodegradable and has …

Magnetic Iron Oxide Nanoparticles: Synthesis, Characteristics, Magnetic Behavior, And Biomedical Applications, Chengyin Fu

Theses

Magnetic iron oxide nanoparticles are attracting increasing attention due to their interesting properties that can be applied in a great number of applications such as catalysis and biomedicine. This thesis focuses on the synthesis, characteristics, and biomedical applications of iron oxide nanoparticles. The two most common iron oxides, including magnetite and maghemite, are discussed in this thesis.

For most of their applications, the magnetic behavior of iron oxide nanoparticles in a fluid is very important, especially, the high gradient magnetic separation of the particles from a nonmagnetic liquid medium, such as blood in the human body. A 2D model, which …

Simulation Of Polymer Solar Cell Characteristics By Amps-1d, Lu Zhang

Theses

Simulation of polymer solar cell characteristics is presented in this study. The solar cells are made of materials such as the following: Poly (3-hexylthiophene): [6, 6]-phenyl C61- butyric acid methylester (P3HT: PCBM) and poly[2,1,3-benzothiadiazole-4,7-diyl[4,4- bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]: [6, 6]-phenyl C₆₁- butyric acid methylester (PCPDTBT: PCBM) are used as active layer materials. Analysis of Microelectronic and Photonic Structures One Dimension (AMPS-1D) is a computer simulation tool for solar cell device characteristics. The first part of this study focuses on the performance and comparison of current-voltage (I-V) simulations of indium oxide (In₂O₃) and tin oxide (SnO₂) …

Glasses For Radiotherapy, Delbert E. Day

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Active Response Of Polymer Materials From External Stimuli – Solvents And Light; Grafting Reactions On Perovskite Layers, Jianxia Zhang

LSU New Orleans Theses and Dissertations

The active response of a series of polymeric materials was investigated. Both solvent activated and light activated thin films and wire systems show dynamic behaviors when exposed to different stimuli.

Solvent mediated fluxional behavior of polymer thin films involved extensive, rapid curling both on infusion and evaporation of good solvents. These films can be either lab-fabricated ones or commercial ones, and the curling behavior can be as fast as seconds. Conditions including polymer materials, chosen solvents, and film geometry can affect the behavior.

Methods that allowed for the creation and retention of distorted wire structures were also developed; the asymmetric …

High Temperature Mechanical Properties Of Zirconium Diboride, L.J. Vandeperre, J. Wang, F. Giuliani

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Ultra-High Temperature Thermal And Mechanical Properties Of Zrb2-Based Ceramics, Greg Hilmas, Bill Fahrenholtz

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Advanced Characterization Of Composite Ultra High Temperature Ceramic Systems, W.E. Lee, Emily Eakins, Heather Jackson, Doni Jayaseelan

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

High Temperature Mechanical, Oxidation And Shock Resistance Properties Of Hot Pressed And Spark Plasma Sintered Tib2-Based Ceramics, Bikramjit Basu, G.B. Raju, V. Jayaram, K.P.J. Reddy

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Microstructures And Thermal Conductivities Of Hot-Pressed Zrb2-Sic Ceramics With A Variety Of Sic Sources, Seongwon Kim, Chang-Sup Kwon, Sung-Min Lee, Yoon-Suk Oh, Hyung-Tae Kim, Byung-Koog Jang

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Where We Are With The Understanding Of Metal/Ceramic Interactions: The Case Of Transition Metal Borides, A. Passerone, F. Valenza, C. Artini, M.L. Muolo

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Correlation Of Shear Strength Between Longitudial And Transverse Specimens, Erasto A. Fernandez

LSU New Orleans Theses and Dissertations

In this thesis, new methods for shear strength are proposed and backed up through extensive experimentation, ABAQUS models and data analysis of Titanium welds of three different alloys. The results are compared with those obtained by using the procedure outlined by AWS B4 for calculating Shear Strength in the transverse and longitudinal directions; this equation is widely used by the American Welding Society (AWS) and all those in search of more efficient designs involving welding.

It is a well-documented issue that the equation provided by AWS yields a large discrepancy between the values for shear strength of longitudinal and transverse …

A Cost Effective Screening Technique For Testing Uhtc Materials Using An Oxyacetylene Torch Flame, Anish Paul, Saranya Venugopal, Jon Binner, Bala Vaidhyanathan, Andrew Heaton, Peter Brown

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Uhtc-Based Hot Structures For Space Re-Entry: Lesson Learned And Future Perspectives, Luigi Scatteia

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Solid State Diffusion Bonding Of Zrc To Zr-Based Alloys, Andrew Gillen, Lyndon Edwards, Daniel Riley, George Franks

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Joining Of Ultra-High Temperature Ceramics, Laura Silvestroni, Diletta Sciti, Laura Esposito, Andreas Glaeser

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Fusion Welding Of Zrb2-Based Ceramics, H.J. Brown, W.G. Fahrenholtz, G.E. Hilmas

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Low Temperature Synthesis And Sintering Of Mechanically Activated Zrb2 Powders, Mustafa Tuncer

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

In-Situ Imaging And Strain Determination During Fracture In A Sic/Sic Ceramic Matrix Composite, Joaquin Ramirez, F. Stoltzenburg, K.T. Faber, J. Almer, D. Singh, J. Routbort

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Microstructure Formation Pathways In Tantalum Carbides, Gregory Thompson, Robert Morris, Billie Wang, Bardford Schulz, Nick Deleon, Christopher Weinberger, Daniel Butts, Stephan Diepetrio, Lawrence Matson

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.

Program, Engineering Conferences International

Ultra-High Temperature Ceramics: Materials For Extreme Environmental Applications II

No abstract provided.