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Electrochemical Testing Of Aluminum-Lithium Alloys 2050, 2195, And The Current Aerospace Industry Standard 7075 To Measure The Galvanic Corrosion Behavior With Ti-6al-4v, Trent Duncan, Kevin Knight 2015 California Polytechnic State University - San Luis Obispo

Electrochemical Testing Of Aluminum-Lithium Alloys 2050, 2195, And The Current Aerospace Industry Standard 7075 To Measure The Galvanic Corrosion Behavior With Ti-6al-4v, Trent Duncan, Kevin Knight

Materials Engineering

This project aimed to characterize the electrochemical behavior of four different aluminum alloys, and determine how much galvanic corrosion would occur when each alloy was coupled to Ti-6Al-4V. The particular alloys tested were 2050-T3, 2050-T852, 2195-T852, and 7075-T7352. These alloys were tested to determine the effects of aging, and adding lithium, to the corrosion behavior of aluminum alloys. Potentiodynamic polarization curves were generated using the Parstat 2273 potentiostat in accordance with ASTM standard G5, and corrosion analysis software was used to produce Tafel fit lines, which determined the open circuit potential (Ecorr) of each sample. Nine tests were …


Measuring And Increasing The Suspension Time Of Lanthanide Oxysulfide Particles With Modifiers Via Fluorescence For Use In Anti-Counterfeiting Applications, Joe Dei Rossi, Tyler Dinslage, Tyler Schelling 2015 California Polytechnic State University - San Luis Obispo

Measuring And Increasing The Suspension Time Of Lanthanide Oxysulfide Particles With Modifiers Via Fluorescence For Use In Anti-Counterfeiting Applications, Joe Dei Rossi, Tyler Dinslage, Tyler Schelling

Materials Engineering

No abstract provided.


Mechanical Testing Of Multi-Construction Composite Tubes For Use In Fly Fishing Rods, Macormik Hopen 2015 California Polytechnic State University - San Luis Obispo

Mechanical Testing Of Multi-Construction Composite Tubes For Use In Fly Fishing Rods, Macormik Hopen

Materials Engineering

A testing protocol was established for measuring the flexure properties of thin-walled tubes constructed of a composite mixture of glass and carbon fibers and epoxy resin for use in Fly Fishing rods. Standard three point bend tests were conducted in accordance with ASTM standard D7329-13 with a span length of six inches. All samples were of the sample length and diameter, allowing direct comparison of the maximum loads reached before failure, which are directly indicative of the Modulus of Rupture (MOR). Two constructions were tested both containing the same unidirectional fiber but with different support structure. These tubes were tested …


Molecular Dynamics Investigation Of The Arabinan-Cellulose Interface For Cellulose Nanocomposite Applications, Luke Thornley 2015 California Polytechnic State University - San Luis Obispo

Molecular Dynamics Investigation Of The Arabinan-Cellulose Interface For Cellulose Nanocomposite Applications, Luke Thornley

Materials Engineering

Atom level computer simulations of the arabinan and cellulose interface were performed to better understand the mechanisms that give arabinan-cellulose composites (ArCCs) their strength with the goal to improve man-made ArCCs. The molecular dynamics (MD) software LAMMPS was used in conjunction with the ReaxFF/c force field to model the bond between cellulose and arabinan. A cellulose nanocrystal with dimensions 51 x 32 x 8 Å was minimized with various weight percent of water, 0%, 3%, 5%, 8%, 10%, and 12%. After the system was equilibrated for at least 100,000 femtoseconds, an arabinan molecule composed of 8 arabinose rings was added …


Characterization Of Laser Deposited Ti-6al-4v To Nb Gradient Alloys, Clincy Cheung 2015 California Polytechnic State University - San Luis Obispo

Characterization Of Laser Deposited Ti-6al-4v To Nb Gradient Alloys, Clincy Cheung

Materials Engineering

An alloy was fabricated with Ti-6Al-4V and Nb powder using laser deposition (LD) to form a compositional gradient. The gradient was deposited, starting with Ti-6Al-4V powder, onto a forged Ti-6Al-4V substrate in an Argon environment. Niobium (Nb) composition increased by 4-at.% with each layer deposited until the composition reached 100-at.% Nb. This process yielded steep thermal gradients and affected the microstructure and mechanical properties across the compositional gradient. To observe the microstructural changes in the alloy, an etched gradient was viewed with optical microscopy at 1000x, where the grain structure was observed to be an acicular α phase at 100-at.% …


Forest Sign Maker, Victor Espinosa III, Kevin Ly, Lisa Yip 2015 California Polytechnic State University - San Luis Obispo

Forest Sign Maker, Victor Espinosa Iii, Kevin Ly, Lisa Yip

Mechanical Engineering

Executive Summary:

The Inyo National Forest is arguably one of the most beautiful locations in California, containing natural masterpieces such as Mount Whitney and the Ancient Bristlecone Pine Forest. Despite its magnificence, the Inyo National Forest can be a treacherous region. The Friends of the Inyo take pride in being able to facilitate the viewing experience for all outdoorsmen by maintaining the mountain trails, which includes providing adequate trail signage.

Unfortunately, there is a fundamental issue with the recent state of trail signage in the Inyo National Forest: the rate at which signs are being vandalized or naturally destroyed is …


Analysis Of Compression Creep Deformation Of 7050 Aluminum Large Scale Open Die Forgings During The Solution Heat Treatment Process, Ashley Lopez, Elysha Cole 2015 California Polytechnic State University - San Luis Obispo

Analysis Of Compression Creep Deformation Of 7050 Aluminum Large Scale Open Die Forgings During The Solution Heat Treatment Process, Ashley Lopez, Elysha Cole

Materials Engineering

A stress, ranging from 104.17 to 166.67 psi, was applied to 0.5 in diameter cylindrical samples of 7050 aluminum using a manufactured fixture that applies stress using an indenter with a diameter of 0.127 in. The stress range used replicates the stresses produced on large scale forgings weighing up to 4000 lbs. We chose a maximum, medium and low stress as our stress parameters. The samples were placed into the fixture for stability then placed in a furnace heated to 890°F which is the solution heat treatment temperature for 7050 aluminum. The heat treatment times varied between 4 and 24 …


Effects Of Initial Forging Temperature, Cooling Rates, And Carbon Content On Primary Alpha Formation In Ti-6al-4v, James Tillman, Hui Wei 2015 California Polytechnic State University - San Luis Obispo

Effects Of Initial Forging Temperature, Cooling Rates, And Carbon Content On Primary Alpha Formation In Ti-6al-4v, James Tillman, Hui Wei

Materials Engineering

Ti-6Al-4V is an alpha-beta titanium alloy system, which contains both alpha and beta phases at room temperature. Both alpha and beta phases provide Ti-6Al-4V a range of different properties for a range of applications. In order to improve the energy efficiency and better satisfy customers’ requirements of less than 52% primary alpha phase, Weber Metals sponsored this project to study the effects of carbon content, forging temperature, and cooling rates on primary alpha formation in Ti-6Al-4V alloys. There has been a lot of discussion as to whether or not carbon, a known alpha stabilizer, will affect the microstructure in small …


Improving Product Design By Predicting Flexural Strength Of A Honeycomb Core Sandwich Panel Composite Using Ply Tensile Strength, Justin Lui, Javal Patel 2015 California Polytechnic State University - San Luis Obispo

Improving Product Design By Predicting Flexural Strength Of A Honeycomb Core Sandwich Panel Composite Using Ply Tensile Strength, Justin Lui, Javal Patel

Materials Engineering

The use of composite sandwich panels has increased in the aerospace industry. Prediction of a theoretical composite construction's flexural properties is important for efficient composite product designs. Utilizing the four point flexure geometry defined by Zodiac Aerospace, Santa Maria, CA, a mechanical model was derived to predict the flexural behavior of a theoretical honeycomb core sandwich composite using laminate tensile properties. The most common failure mode of Zodiac Aerospace’s four point bend test is a failure in tension of the bottom laminate. Given this information, ASTM D3039 (Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials) was chosen …


Measuring Performance Of Paint Coating Via Laboratory And Field Testing, Eugene Leung, Rocco Lattanzio 2015 California Polytechnic State University, San Luis Obispo

Measuring Performance Of Paint Coating Via Laboratory And Field Testing, Eugene Leung, Rocco Lattanzio

Materials Engineering

No abstract provided.


Electrolytic Recovery Of Bismuth And Copper As A Powder From Acidic Sulfate Effluents Using An Emew® Cell, Wei Jin, Paul I. Laforest, Alex Luyima, Weldon Read, Luis M. Navarro, Michael S. Moats 2015 Missouri University of Science and Technology

Electrolytic Recovery Of Bismuth And Copper As A Powder From Acidic Sulfate Effluents Using An Emew® Cell, Wei Jin, Paul I. Laforest, Alex Luyima, Weldon Read, Luis M. Navarro, Michael S. Moats

Materials Science and Engineering Faculty Research & Creative Works

Effective removal of bismuth is a primary concern during copper electrorefining. A novel electrowinning process using an emew® cell was developed to recover bismuth and copper from a copper electrorefining waste stream. Significant removal and co-deposition of copper and bismuth were achieved from a highly acidic sulfate industrial effluent using a current density of 350 A m-2, but the current efficiency was low (27%). Operating at a lower current density (75 A m-2) facilitated the preferred removal of Cu, while increasing current efficiency to 67.4% due to the decrease of aside-reaction. Consequently, a two-stage process was …


Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin 2015 California Polytechnic State University, San Luis Obispo

Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin

Master's Theses

Water soluble conjugated polyelectrolytes (CPEs), which fall under the category of conductive polymers, possess numerous advantages over other conductive materials for the fabrication of electronic devices. Namely, the processing of water soluble conjugated polyelectrolytes into thin film electronic devices is much less costly as compared to the processing of inorganic materials. Moreover, the handling of conjugated polyelectrolytes can be performed in a much more environmentally friendly manner than in the processing of other conjugated polymers because conjugated polyelectrolytes are water soluble, whereas other polymers will only dissolve in toxic organic solvents. The processing of electronic devices containing inorganic constituents such …


Impact Of Stoichiometry On Structural And Optical Properties Of Sputter Deposited Multicomponent Tellurite Glass Films, Okechukwu Ogbuu, Qingyang Du, Hongtao Lin, Lan Li, Yi Zou, Erick Koontz, Charmayne Smith (Lonergan), Sylvain Danto, Kathleen Richardson, Juejun Hu 2015 Missouri University of Science and Technology

Impact Of Stoichiometry On Structural And Optical Properties Of Sputter Deposited Multicomponent Tellurite Glass Films, Okechukwu Ogbuu, Qingyang Du, Hongtao Lin, Lan Li, Yi Zou, Erick Koontz, Charmayne Smith (Lonergan), Sylvain Danto, Kathleen Richardson, Juejun Hu

Materials Science and Engineering Faculty Research & Creative Works

Multicomponent TeO2-Bi2O3-ZnO (TBZ) glass thin films were prepared using RF magnetron sputtering under different oxygen flow rates. The influences of oxygen flow rate on the structural and optical properties of the resulting thin films were investigated. We observed that thin films sputtered in an oxygen-rich environment are optically transparent while those sputtered in an oxygen-deficient environment exhibit broadband absorption. The structural origin of the optical property variation was studied using X-ray diffraction, X-ray photoelectron spectroscopy, Raman Spectroscopy, and transmission electron microscopy which revealed that the presence of under-coordinated Te leads to the observed optical …


Chemical Oxidative Polymerization, Optical, Electrochemical And Kinetic Studies Of 8-Amino-2-Naphthol, Fatih Dogan, Ismet Kaya, Ali Bilici, Mehmet Yildirim 2015 Missouri University of Science and Technology

Chemical Oxidative Polymerization, Optical, Electrochemical And Kinetic Studies Of 8-Amino-2-Naphthol, Fatih Dogan, Ismet Kaya, Ali Bilici, Mehmet Yildirim

Materials Science and Engineering Faculty Research & Creative Works

Here the polymerization of 8-amino-2-naphthol (AN) is reported without use of an additional external template, surfactants or functional dopants. For this, NaOCl and hydrochloride acid solution (1.0 M) were used as oxidant and reaction medium, respectively. The structure of oligomer was elucidated by FT-IR, UV–vis and 1 H-NMR techniques. The number average molecular weight of oligomer was found to be 2200Da with a polydispersity index of 1.4 by size exclusion chromatography. This oligomer exhibited a multicolor emission behavior as it was excited at different wavelengths. Redox states were clarified by cyclic voltammetry (CV) technique and the relationship between anodic/cathodic peak …


Self-Contained Breathing Apparatus For Firefighter With A Permanent Stoma, Jason Delgadillo, Aaron Wheeler, Zachary Wishbow 2015 California Polytechnic State University, San Luis Obispo

Self-Contained Breathing Apparatus For Firefighter With A Permanent Stoma, Jason Delgadillo, Aaron Wheeler, Zachary Wishbow

Biomedical Engineering

The purpose of this project was to create a unique SCBA (self-contained breathing apparatus) for a firefighter named Chris Gauer. This prototype consists of a SCBA headgear connected to a polycarbonate-formed stoma mask with a medical-grade sanitary silicone hose.


Investigating The Cause Of Unique Mechanical Behavior In Platinum Alloy Guidewire Tips, Evan Borgeson, Alfred Rosen 2015 California Polytechnic State University - San Luis Obispo

Investigating The Cause Of Unique Mechanical Behavior In Platinum Alloy Guidewire Tips, Evan Borgeson, Alfred Rosen

Materials Engineering

The platinum alloy used by Abbott Vascular in guidewire tips exhibits a yielding behavior characterized by an abrupt transition from elastic to plastic zones and high ductility. This yielding behavior was hypothesized to be a result of one of three structural phenomena: ordering, solute strain aging, or interstitial strain aging. To test for these strengthening mechanisms in the wire, X-ray diffraction analysis, heat treatments, and tensile testing were completed. The wire has a diameter of 0.0025 inches and was supplied in two forms, the final stress relieved state, and as-drawn from the production line. Heat treatments were performed at 130 …


Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook 2015 California Polytechnic State University - San Luis Obispo

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …


Elevated Temperature Effects On The Mechanical Properties Of Age Hardened 6xxx Series Aluminum Alloy Extrusions, Rachael Donovan, Rose Fortune, Robert Trout 2015 California Polytechnic State University - San Luis Obispo

Elevated Temperature Effects On The Mechanical Properties Of Age Hardened 6xxx Series Aluminum Alloy Extrusions, Rachael Donovan, Rose Fortune, Robert Trout

Materials Engineering

The purpose of this project is to determine if over-aging of aluminum causes the yield or tensile strength to fall below the minimum strength values set by the aluminum industry. Extruded aluminum alloys, 6061-T6, 6063-T6, and two proprietary alloys, HS6X-T6 and RX82-T6, were exposed to reheating treatments at extended times and temperatures. The three temperatures were 350°F, 390°F, and 425°F. The times of reheat increased logarithmically from 30 minutes to 64 hours. The samples were tensile tested to determine the tensile strength and yield strength. Statistical methods helped model the behavior of yield and tensile strength as a function of …


Capillary Channel Flow (Ccf) Eu2-02 On The International Space Station (Iss): An Experimental Investigation Of Passive Bubble Separations In An Open Capillary Channel, Mark M. Weislogel, Andrew P. Wollman, Ryan M. Jenson, John T. Geile, John F. Tucker, Brentley M. Wiles, Andy L. Trattner, Claire DeVoe, Lauren M. Sharp, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer 2015 Portland State University

Capillary Channel Flow (Ccf) Eu2-02 On The International Space Station (Iss): An Experimental Investigation Of Passive Bubble Separations In An Open Capillary Channel, Mark M. Weislogel, Andrew P. Wollman, Ryan M. Jenson, John T. Geile, John F. Tucker, Brentley M. Wiles, Andy L. Trattner, Claire Devoe, Lauren M. Sharp, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer

Mechanical and Materials Engineering Faculty Publications and Presentations

It would be signicantly easier to design fluid systems for spacecraft if the fluid phases behaved similarly to those on earth. In this research an open 15:8 degree wedge-sectioned channel is employed to separate bubbles from a two-phase flow in a microgravity environment. The bubbles appear to rise in the channel and coalesce with the free surface in much the same way as would bubbles in a terrestrial environment, only the combined effects of surface tension, wetting, and conduit geometry replace the role of buoyancy. The host liquid is drawn along the channel by a pump and noncondensible gas bubbles …


New Screening Methodology For Selection Of Polymeric Materials For Transdermal Drug Delivery Devices, Roberto P. Falcone 2015 New Jersey Institute of Technology

New Screening Methodology For Selection Of Polymeric Materials For Transdermal Drug Delivery Devices, Roberto P. Falcone

Dissertations

As medical advances extend the human lifespan, the level of chronic illnesses will increase and thus straining the needs of the health care system that, as a result, governments will need to balance expenses without upsetting national budgets.

Therefore, the selection of a precise and affordable drug delivery technology is seen as the most practical solution for governments, health care professionals, and consumers.

Transdermal drug delivery patches (TDDP) are one of the best economical technologies that are favored by pharmaceutical companies and physicians alike because it offers fewer complications when compared to other delivery technologies. TDDP provides increased efficiency, safety …


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