Open Access. Powered by Scholars. Published by Universities.®

Materials Science and Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

5,531 Full-Text Articles 7,819 Authors 964,021 Downloads 73 Institutions

All Articles in Materials Science and Engineering

Faceted Search

5,531 full-text articles. Page 1 of 96.

High Temperature Oxidation Kinetics Of Dysprosium Particles, Brian J. Jaques, Darryl P. Butt 2015 Boise State University

High Temperature Oxidation Kinetics Of Dysprosium Particles, Brian J. Jaques, Darryl P. Butt

Materials Science and Engineering Faculty Publications and Presentations

Rare earth elements have been recognized as critical materials for the advancement of many strategic and green technologies. Recently, the United States Department of Energy has invested many millions of dollars to enhance, protect, and forecast their production and management. The work presented here attempts to clarify the limited and contradictory literature on the oxidation behavior of the rare earth metal, dysprosium. Dysprosium particles were isothermally oxidized from 500 to 1000 °C in N2–(2%, 20%, and 50%) O2 and Ar–20% O2 using simultaneous thermal analysis techniques. Two distinct oxidation regions were identified at each isothermal ...


Thermal Kinetics Of Ion Irradiation Hardening In Selected Alloys For The Canadian Gen. Iv Nuclear Reactor Concept, Heygaan Rajakumar 2015 The University of Western Ontario

Thermal Kinetics Of Ion Irradiation Hardening In Selected Alloys For The Canadian Gen. Iv Nuclear Reactor Concept, Heygaan Rajakumar

Electronic Thesis and Dissertation Repository

Canada is designing supercritical water fission reactors (SCWR) to increase the thermal efficiency of nuclear power generation from ~34% to ~48%. The temperature and pressure of a supercritical water reactor core is very high compared to a CANDU reactor. This thesis examines irradiation hardening and thermal recovery of two candidate alloys, AISI 310 and Inconel 800H, for the Canadian SCWR.

Samples of both alloys are mechanically ground and polished, then irradiated using 8.0 MeV Fe ions. The use of ion irradiation safely and quickly simulates neutron damage. The change in the hardness of the samples is then studied during ...


First-Principles Studies Of Perovskite Compounds For Thermoelectric Applications, Penelope E. Ackerman, Lan Li (Mentor) 2015 Carnegie Mellon University

First-Principles Studies Of Perovskite Compounds For Thermoelectric Applications, Penelope E. Ackerman, Lan Li (Mentor)

Idaho Conference on Undergraduate Research

Computational modeling techniques have been used to provide detailed insights into the structure-property relationships of materials. We have collaborated with the National Institute of Standards and Technology to develop various perovskite compounds with desired thermoelectric properties. We have used density functional theory-based approaches to study structural stability and electrical properties of R2(FeCo)O6 perovskite compounds (R = Pr, Nd, Sm, Eu and Gd), for which Fe and Co randomly occupy the B-site. Vienna ab-initio simulation package (VASP) has been performed to optimize geometry and structure. Superlattice and locally disordered phases have been compared through a total energy minimization ...


Experimental Evaluation Of Tensile Strength And Young’S Modulus Of Woven Jute Fiber And Polyurethane Composite, Shrikant Shinde, A. V. Salve 2015 Department of mechanical engineering,Vishwakarma Institute of Information Technlogy, Pune-48, India.

Experimental Evaluation Of Tensile Strength And Young’S Modulus Of Woven Jute Fiber And Polyurethane Composite, Shrikant Shinde, A. V. Salve

Innovative Research Publications IRP India

Natural fiber reinforced composites (NFRCs) are increasingly used in a variety of commercial applications, but there has been little theoretical, micromechanical modeling of structure/property relationships in these materials. These can’t be met by conventional metal alloys. The scope of possible uses of natural fibers is enormous.Plenty of research work is done on natural fiber composites. But, woven jute fiber and bio based polyurethane resin matrix is not used extensively for research studies. Mostly mathematical model is used to investigate and predict the properties and fiber loads effect on mechanical properties. The combination of jute fiber with PU ...


Comparison Of Beta Backscatter And X-Ray Fluorescence Methods To Measure Coating Thickness, Sergio Palomo, Bernice Mills 2015 Rutgers University - New Brunswick/Piscataway

Comparison Of Beta Backscatter And X-Ray Fluorescence Methods To Measure Coating Thickness, Sergio Palomo, Bernice Mills

STAR (STEM Teacher and Researcher) Program Posters

This work compares and assesses the effectiveness of beta backscatter (BB) and x-ray fluorescence (XRF) for measuring the thickness of gold coatings on two substrates: silicon and an iron-nickel alloy. A set of samples of known gold coating thickness, ranging from 0.5 – 4.0 microns, was measured in each case along with the substrate alone. In BB the number of electrons (beta particles from a very small radioactive source, Pm-147 in this case) backscattered from a sample in a fixed time period is counted. The XRF method uses x-rays generated in the sample from a primary x-ray beam of ...


Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-nguyen, Bernice Mills 2015 Templeton High School

Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-Nguyen, Bernice Mills

STAR (STEM Teacher and Researcher) Program Posters

X-rays are widely used in medicine and materials science to identify impurities or fractures within the target object. In material science, x-rays can be used to identify the thickness of samples with different material densities. The current method is to collect a radiograph using estimated conditions, evaluate the results, then make changes to the conditions. The residual image can be rescanned making it possible to obtain an image of lower radiographic density. By tabulating or graphing the effects of energy changes and rescans, a more informed choice of conditions is possible.

For this study, six materials were chosen with a ...


Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne 2015 El Camino Fundamental High School

Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne

STAR (STEM Teacher and Researcher) Program Posters

During long term space missions, it is necessary to have a reliable source of energy. Solar cells are an easy and reliable way to convert energy from the sun to electrical energy. NASA has used solar cells manufactured on Earth as an energy source for many of its missions. In order to develop technologies that will enable high efficiency solar cells, we are synthesizing nanostructured materials. A range of nanostructured materials, such as titanium dioxide nanowires, nickel nanoparticles, copper nanoparticles, and silver nanoparticles/nanowires, are synthesized. In this work, we are reporting on the synthesis of these nanomaterials and the ...


Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-Nguyen, Bernice Mills 2015 Templeton High School

Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-Nguyen, Bernice Mills

STAR (STEM Teacher and Researcher) Program Posters

X-rays are widely used in medicine and materials science to identify impurities or fractures within the target object. In material science, x-rays can be used to identify the thickness of samples with different material densities. The current method is to collect a radiograph using estimated conditions, evaluate the results, then make changes to the conditions. The residual image can be rescanned making it possible to obtain an image of lower radiographic density. By tabulating or graphing the effects of energy changes and rescans, a more informed choice of conditions is possible.

For this study, six materials were chosen with a ...


Hydrometallurgy Of Phosphate Rock And The Recovery Of Uranium, Fathi Habashi 2015 Laval University, Quebec City, Canada

Hydrometallurgy Of Phosphate Rock And The Recovery Of Uranium, Fathi Habashi

Fathi Habashi

Phosphate rock of sedimentary origin contains on the average 0.01 % uranium. Since large tonnage of this rock is used annually to produce fertilizers, this represented an important potential source of uranium. Before the discovery of rich uranium deposits this source was developed on industrial scale. The production of phosphoric acid by sulfuric acid process is at present facing the problem of disposal of gypsum; about 1.5 tons of gypsum is produced per ton of rock processed. This material contains all the radium originally present in the rock which results from the radioactive decay of uranium. As a result ...


Metallurgical Chemistry, Fathi Habashi 2015 Laval University, Quebec City, Canada

Metallurgical Chemistry, Fathi Habashi

Fathi Habashi

Metallurgical chemistry is the most ancient science of chemistry. It is related to the recovery of metals from ores and their refining. In its modern form, it involves separation of finely ground minerals by flotation, melting of ores, aqueous processing of ores, and the application of electric current to separate and purify metals from aqueous solution or from a fused salt. Metallurgical chemistry is closely related to the chemical industry.


Fundamental Problems In Porous Materials: Experiments & Computer Simulation, Zhanping Xu 2015 University of Nebraska-Lincoln

Fundamental Problems In Porous Materials: Experiments & Computer Simulation, Zhanping Xu

Engineering Mechanics Dissertations & Theses

Porous materials have attracted massive scientific and technological interest because of their extremely high surface-to-volume ratio, molecular tunability in construction, and surface-based applications. Through my PhD work, porous materials were engineered to meet the design in selective binding, self-healing, and energy damping. For example, crystalline MOFs with pore size spanning from a few angstroms to a couple of nanometers were chemically engineered to show 120 times more efficiency in binding of large molecules. In addition, we found building blocks released from those crystals can be further patched back through a healing process at ambient and low temperatures down to -56 ...


Knowledge Discovery Models For Product Design, Assembly Planning And Manufacturing System Synthesis, Mohamed Kashkoush 2015 University of Windsor

Knowledge Discovery Models For Product Design, Assembly Planning And Manufacturing System Synthesis, Mohamed Kashkoush

Electronic Theses and Dissertations

The variety of products has been growing over the last few decades so that the challenges for designers and manufacturers to enhance their design and manufacturing capabilities, responsively and cost-effectively are greater than ever. The main objective of this research is to help designers and manufacturers cope with the increasing variety management challenges by exploiting the data records of existing or old products, along with appropriate Knowledge Discovery (KD) models, in order to extract the embedded knowledge in such data and use it to speed-up the development of new products. Four product development activities have been successfully addressed in this ...


Development Of A National Anthropogenic Heating Database With An Extrapolation For International Cities, David J. Sailor, Matei Georgescu, Jeffrey M. Milne, Melissa A. Hart 2015 Portland State University

Development Of A National Anthropogenic Heating Database With An Extrapolation For International Cities, David J. Sailor, Matei Georgescu, Jeffrey M. Milne, Melissa A. Hart

Mechanical and Materials Engineering Faculty Publications and Presentations

Given increasing utility of numerical models to examine urban impacts on meteorology and climate, there exists an urgent need for accurate representation of seasonally and diurnally varying anthropogenic heating data, an important component of the urban energy budget for cities across the world. Incorporation of anthropogenic heating data as inputs to existing climate modeling systems has direct societal implications ranging from improved prediction of energy demand to health assessment, but such data are lacking for most cities. To address this deficiency we have applied a standardized procedure to develop a national database of seasonally and diurnally varying anthropogenic heating profiles ...


Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall 2015 United States Military Academy

Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall

International Journal of Nuclear Security

The ability to determine the time since the forming of seized nuclear material would provide crucial data to be used in its investigation. This paper examines the effects of radiolytic damage caused by the decay of uranium isotopes and assesses the potential forensic utility of examination of these damage regions for determining the time since forming of a metal sample. This paper draws parallels from studies of fission track dating in mineral samples under geologic time and proposes modifications to previously published work in the field of α-recoil track dating in order to determine the time since a metal sample ...


Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall 2015 United States Military Academy

Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall

International Journal of Nuclear Security

The ability to determine the time since forming of seized nuclear material would provide crucial data to be used in its investigation. The time dependent processes of diffusion relevant to this need are examined; to include grain boundary diffusion, and discontinuous precipitation, and an assessment is performed of the utility of examination of impurity and alloying element concentration profiles for use as a pre-detonation nuclear forensics tool for determining the age of a metal sample. Several examples illustrate the effects of time on both binary alloys and multi-component systems. Parallels are drawn from studies of diffusion in mineral samples under ...


Inert-Gas Condensed Co-W Nanoclusters: Formation, Structure And Magnetic Properties, Farhad Reza Golkar-Fard 2015 University of Nebraska - Lincoln

Inert-Gas Condensed Co-W Nanoclusters: Formation, Structure And Magnetic Properties, Farhad Reza Golkar-Fard

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Rare-earth permanent magnets are used extensively in numerous technical applications, e.g. wind turbines, audio speakers, and hybrid/electric vehicles. The demand and production of rare-earth permanent magnets in the world has in the past decades increased significantly. However, the decrease in export of rare-earth elements from China in recent time has led to a renewed interest in developing rare-earth free permanent magnets. Elements such as Fe and Co have potential, due to their high magnetization, to be used as hosts in rare-earth free permanent magnets but a major challenge is to increase their magnetocrystalline anisotropy constant, K1, which ...


Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov 2015 University of Birmingham

Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

Under sleeper pads (USPs) are the component installed under the concrete sleepers generally to improve railway track resilience. Initial development in Europe, particularly in Austria, has encouraged the adoption of the component around the world. In practice, the component has commonly been used in certain applications, mainly to moderate track stiffness in special locations such as turnouts, crossings, and level crossing. In heavy haul operation, the heavier wagons result in sturdier bogie structures, higher unsprung mass, and then higher level of wheel-rail interaction forces. Accordingly, the application of USPs to mitigate detrimental impact load consequence on track structure is presented ...


Consumer Perceptions Towards Package Designs: A Cross Cultural Study, Romica Chandra Lal, Fritz Yambrach, Lucy McProud 2015 San Jose State University

Consumer Perceptions Towards Package Designs: A Cross Cultural Study, Romica Chandra Lal, Fritz Yambrach, Lucy Mcproud

Journal of Applied Packaging Research

The choice of one package or the other can be an economic decision or can be influenced by cultural acceptance or perception of individual convenience. Product package systems can be designed for one-time use or multiple-use purposes. Package perceptions in different countries typically develop from a variety of factors, including climate, lifestyle, and cultural acceptance with regard to particular products. In an increasingly global economy with multinational firms marketing products worldwide, it is important to understand the differences between consumer needs and consumer responses to product-package systems.

The objective of this research was to examine consumer perceptions of different product ...


Characterization Of Pressure-Driven And Electro-Kinetically Driven Flow In A Micro-Fluidic Chip Using Particle Imaging Velocimetry, Alexis Weckel 2015 California Polytechnic State University - San Luis Obispo

Characterization Of Pressure-Driven And Electro-Kinetically Driven Flow In A Micro-Fluidic Chip Using Particle Imaging Velocimetry, Alexis Weckel

Master's Theses and Project Reports

The flow profiles of pressure-driven and electro-kinetic driven flows were compared for a microfluidic chip. It was found that the pressure-driven flow had a parabolic profile while the electro-kinetic flow had a plug shaped flow profile. The measured velocities were similar to those determined by the Poiseuille flow model and the Helmholtz-Smoltchowski equation. Flow uniformity is very important for control in microfluidic mixers. Parabolic flow profiles lead to inconsistent reactions while the more uniform plug shape flow allow for a more steady reaction across the channel. Previous work had been performed to measure the flow of a solution of fluorescent ...


Specific Heat Investigation For Line Nodes In Heavily Overdoped Ba1−Xkxfe2as2, J. S. Kim, G. R. Stewart, Yong Liu, Thomas A. Lograsso 2015 University of Florida

Specific Heat Investigation For Line Nodes In Heavily Overdoped Ba1−Xkxfe2as2, J. S. Kim, G. R. Stewart, Yong Liu, Thomas A. Lograsso

Ames Laboratory Publications

Previous research has found that the pairing symmetry in the iron-based superconductor Ba1−xKxFe2As2 changes from nodeless s wave near optimally doped, x≈0.4−0.55 and Tc>30K, to nodal (either d wave or s wave) at the pure end point, x=1 and Tc<4K. Intense theoretical interest has been focused on this possibility of changing pairing symmetry, where in the transition region both order parameters would be present and time-reversal symmetry would be broken. Here we report specific heat measurements in zero and applied magnetic fields down to 0.4 K of three individual single crystals, free of low-temperature magnetic anomalies, of heavily overdoped Ba1−xKxFe2As2,x=0.91, 0.88, and 0.81. The values for Tcmid are 5.6, 7.2, and 13 K and for Hc2≈4.5, 6, and 20 T, respectively. The data can be analyzed in a two-gap scenario, Δ2/Δ1≈4, with the magnetic field dependence of γ(=C/TasT→0) showing an anisotropic “S-shaped” behavior vs H, with the suppression of the lower gap by 1 T and γ≈H1/2 overall. Although such a nonlinear γ vs H is consistent with deep minima or nodes in the gap structure, it is not clear evidence for one, or both, of the gaps being nodal in these overdoped samples. Thus, following the established theoretical analysis of the specific heat of d-wave cuprate superconductors containing line nodes, we present the specific heat normalized by H1/2 plotted vs T/H1/2 of these heavily overdoped Ba1−xKxFe2As2 samples which—thanks to the absence of magnetic impurities in our sample—convincingly shows the expected scaling for line node behavior for the larger gap for all three compositions. There is, however, no clear observation of the nodal behavior C∝αT2 in zero field at low temperatures, with α≤2mJ/molK3 being consistent with the data. This, together with the scaling, leaves open the possibility of extreme anisotropy in a nodeless larger gap, Δ2, such that the scaling works for fields above 0.25–0.5 T (0.2–0.4 K in temperature units), where this is an estimate for the size of the deep minima in the Δ2∼20−25K gap. Therefore, the location of the change from nodeless to nodal gaps between optimally doped and heavily overdoped Ba1−xKxFe2As2 based on the present work may be closer to the KFe2As2 end point than x=0.91.


Digital Commons powered by bepress