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Quantum Modeling Of Thermodynamic Properties Of Warm Dense Aluminum, Nicholas Termini, Gennady Miloshesky, Ahmed Hassanein
Quantum Modeling Of Thermodynamic Properties Of Warm Dense Aluminum, Nicholas Termini, Gennady Miloshesky, Ahmed Hassanein
The Summer Undergraduate Research Fellowship (SURF) Symposium
Warm dense matter is attracting a lot of attention in the scientific community, due to its formation during intense laser-matter interaction and inertial confinement fusion. However, there is no accurate solution to mapping out the thermodynamic properties of warm dense matter. Experimental data are also incredibly scarce making computational models an incredibly useful tool. This paper provides equation of state (EOS) data for aluminum at specific densities within the warm dense matter regime. The EOS data were calculated using quantum molecular dynamics, which was performed by the computational package QuatumEspresso. EOS were determined by collecting and recording pressure after achieving …
Altered Combustion Characteristics Of Aluminum Fuels Through Low-Level Fluoropolymer Inclusions With And Without In Situ Nanoaluminum., Courtney K. Murphy, Brandon Terry, Steven F. Son
Altered Combustion Characteristics Of Aluminum Fuels Through Low-Level Fluoropolymer Inclusions With And Without In Situ Nanoaluminum., Courtney K. Murphy, Brandon Terry, Steven F. Son
The Summer Undergraduate Research Fellowship (SURF) Symposium
Aluminum inclusions have been widely used to increase the specific impulse of solid rocket propellant. However, issues arise with the addition of aluminum in the form of agglomeration, which can cause kinetic and thermal losses (i.e., two-phase flow losses) through the nozzle, which can reduce motor performance by as much as 10%. Reduction of agglomerate size may reduce the effect of two-phase flow losses. Polytetrafluoroethylene (PTFE or TeflonTM) inclusions into aluminum via mechanical activation (MA, milling) have been shown to produce a smaller coarse agglomerate size due to microexplosion of the composite particles at the propellant surface. Perflouroalkoxy …
Elevated Temperature Effects On The Mechanical Properties Of Age Hardened 6xxx Series Aluminum Alloy Extrusions, Rachael Donovan, Rose Fortune, Robert Trout
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 …
Effect Of Time Delay Between Etching And Adhesive Bonding (“Outlife” Time) On Lap-Shear Strength Of Aluminum Alloys Using Environmentally-Friendly P2 Etch, Josh Barkhimer, Matthew Erich, Gokul Nair
Effect Of Time Delay Between Etching And Adhesive Bonding (“Outlife” Time) On Lap-Shear Strength Of Aluminum Alloys Using Environmentally-Friendly P2 Etch, Josh Barkhimer, Matthew Erich, Gokul Nair
Materials Engineering
Raytheon Company currently uses a Forest Products Laboratory (FPL) paste etchant for preparing aluminum surfaces for adhesive bonding, and FPL is a source of hazardous hexavalent chromium. The goal of this study was to evaluate a less-toxic P2 paste etchant as a possible replacement. Coupons of 2024-T3, 6061-T6, and 7075-T6 grades of aluminum alloy were solvent-degreased, abrasively cleaned, and etched at room temperature using P2 paste following a strict protocol adopted from Raytheon. Coupons were then left exposed to air for assigned time intervals (or “outlife” times) of 0, 1, 4, 8, 16, and 63 or 72 hours. The aluminum …
Friction Bit Joining Of Dissimilar Combinations Of Dp 980 Steel And Aa 7075, Rebecca Hilary Peterson
Friction Bit Joining Of Dissimilar Combinations Of Dp 980 Steel And Aa 7075, Rebecca Hilary Peterson
Theses and Dissertations
Friction Bit Joining (FBJ) is a new technology that allows lightweight metals to be joined to advanced high-strength steels (AHSS). Joining of dissimilar metals is especially beneficial to the automotive industry because of the desire to use materials such as aluminum and AHSS in order to reduce weight and increase fuel efficiency. In this study, FBJ was used to join 7075 aluminum and DP980 ultra-high-strength steel. FBJ is a two-stage process using a consumable bit. In the first stage, the bit cuts through the top material (aluminum), and in the second stage the bit is friction welded to the base …
Inter-Laboratory Variation In The Chemical Analysis Of Acidic Forest Soil Reference Samples From Eastern North America, D. S. Ross, S. W. Bailey, R. D. Briggs, J. Curry, I. J. Fernandez, G. Fredriksen, C. L. Goodale, P. W. Hazlett, P. R. Heine, C. E. Johnson, J. T. Larson, G. B. Lawrence, R. K. Kolka, R. Ouimet, D. Paré, D. De B. Richter, C. D. Schirmer, R. A. Warby
Inter-Laboratory Variation In The Chemical Analysis Of Acidic Forest Soil Reference Samples From Eastern North America, D. S. Ross, S. W. Bailey, R. D. Briggs, J. Curry, I. J. Fernandez, G. Fredriksen, C. L. Goodale, P. W. Hazlett, P. R. Heine, C. E. Johnson, J. T. Larson, G. B. Lawrence, R. K. Kolka, R. Ouimet, D. Paré, D. De B. Richter, C. D. Schirmer, R. A. Warby
Civil and Environmental Engineering
Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. Soil proficiency programs do not generally include forest soil samples that are highly acidic, high in extractable Al, low in extractable Ca and often high in carbon. To determine the uncertainty associated with specific analytical methods for forest soils, we collected and distributed samples from two …
Development And Demonstration Of Critical Components Of Aluminum Based Energy Storage Devices Using The Chloroaluminate Ionic Liquids, Mengqi Zhang
Doctoral Dissertations
This dissertation considers the development of porous carbon materials as the substrates for Al deposition/dissolution in an Al based ionic liquid flow battery (ILFB) and demonstration of an Al based hybrid supercapacitor. The Aluminum chloride/ 1-ethyl-3-methylimidazolium chloride chloroaluminate ionic liquid is utilized as the electrolyte for these Al based energy storage devices. The ILFB has less capital cost than the all-vanadium redox flow battery because of the inexpensive AlCl3. The feasibility to equip a tank of solid aluminum chloride in an ILFB system aiming to improve energy density is investigated. A critical range of temperature data (50-130 celsius …
Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya
Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya
Jason R. Hattrick-Simpers
A high-throughput high-sensitivity optical technique for measuringmagnetostriction of thin-film composition-spread samples has been developed. It determines the magnetostriction by measuring the induced deflection of micromachined cantilever unimorph samples. Magnetostrictionmeasurements have been performed on as-deposited Fe–Ga and Fe–Ga–Al thin-film composition spreads. The thin-film Fe–Ga spreads display a similar compositional variation of magnetostriction as bulk. A previously undiscovered peak in magnetostriction at low Ga content was also observed and attributed to a maximum in the magnetocrystalline anisotropy. Magnetostrictive mapping of the Fe–Ga–Al ternary system reveals the possibility of substituting up to 8at.%Al in Fe70Ga30 without significant degradation of magnetostriction.
Development Of A Metal-Printing 3d Printer At The University Of North Dakota, Benjamin Kading, Michaela Kegley, Tiana Delzer, Jeremy Straub, Scott Kerlin
Development Of A Metal-Printing 3d Printer At The University Of North Dakota, Benjamin Kading, Michaela Kegley, Tiana Delzer, Jeremy Straub, Scott Kerlin
Jeremy Straub
Three-dimensional (3D) printing is being used for numerous applications: from consumer hobbies to the development of aircraft parts. However, inexpensive 3D printers have been constrained in material selection to plastic. These printer use the fused deposition modeling (FDM) method of printing, which is a relatively new technology that utilizes computer numerical control (CNC) techniques to deposit melted material at specific places. Other methods, for example, include laser sintering and stereolithography. With 3D printing, layers are stacked upon each other and via this compilation of layers, a 3D object is formed. Currently there are a variety of materials that can be …
A Constitutive Model For Entangled Polymers Incorporating Binary Entanglement Pair Dynamics And A Configuration Dependent Friction Coefficient, David W. Mead, Nilanjana Banerjee, Joontaek Park
A Constitutive Model For Entangled Polymers Incorporating Binary Entanglement Pair Dynamics And A Configuration Dependent Friction Coefficient, David W. Mead, Nilanjana Banerjee, Joontaek Park
Chemical and Biochemical Engineering Faculty Research & Creative Works
Following recent work [e.g., J. Park et al., J. Rheol. 56, 1057-1082 (2012); T. Yaoita et al., Macromolecules 45, 2773-2782 (2012); and G. Ianniruberto et al., Macromolecules 45, 8058-8066 (2012)], we introduce the idea of a configuration dependent friction coefficient (CDFC) based on the relative orientation of Kuhn bonds of the test and surrounding matrix chains. We incorporate CDFC into the "toy" model of Mead et al. [Macromolecules 31, 7895-7914 (1998)] in a manner akin to Yaoita et al. [Nihon Reoroji Gakkaishi 42, 207-213 (2014)]. Additionally, we incorporate entanglement dynamics (ED) of discrete entanglement pairs into the new Mead-Banerjee-Park (MBP) …
Producing High Strength Aluminum Alloy By Combination Of Equal Channel Angular Pressing And Bake Hardening, Hamid Alihosseini, Mohsen Asle Zaeem, Kamran Dehghani, Ghader Faraji
Producing High Strength Aluminum Alloy By Combination Of Equal Channel Angular Pressing And Bake Hardening, Hamid Alihosseini, Mohsen Asle Zaeem, Kamran Dehghani, Ghader Faraji
Materials Science and Engineering Faculty Research & Creative Works
A combination of severe plastic deformation by equal channel angular pressing (ECAP) and bake hardening (BH) was used to produce high strength ultrafine-grained AA6061 aluminum alloy. 2, 4 and 8 passes of ECAP were performed, and the bake hardenability of samples was tested by 6% pre-straining followed by baking at 200 °C for 20 min. The microstructures obtained for various passes of ECAP were characterized by XRD, EBSD, and TEM techniques. The microstructures were refined from an average grain size of 20 µm to 212 nm after 8 passes of ECAP. Maximum bake hardenability of 110 MPa, and final yield …
Fuzzy Logic Based Model For Predicting Surface Roughness Of Machined Al-Si-Cu-Fe Die Casting Alloy Using Different Additives-Turning
Faculty of Engineering University of Malaya
This paper presents a fuzzy logic artificial intelligence technique for predicting the machining performance of Al-Si-Cu-Fe die casting alloy treated with different additives including strontium, bismuth and antimony to improve surface roughness. The Pareto-ANOVA optimization method was used to obtain the optimum parameter conditions for the machining process. Experiments were carried out using oblique dry CNC turning. The machining parameters of cutting speed, feed rate and depth of cut were optimized according to surface roughness values. The results indicated that a cutting speed of 250 m/min, a feed rate of 0.05 mm/rev, and a depth of cut of 0.15 mm …
Properties Of Cu(In,Ga,Al)Se² Thin Films Fabricated By Magnetron Sputtering, Talaat A. Hameed, Wei Cao, Bahiga A. Mansour, Inas K. Elzawaway, El-Metwally M. Abdelrazek, Hani E. Elsayed-Ali
Properties Of Cu(In,Ga,Al)Se² Thin Films Fabricated By Magnetron Sputtering, Talaat A. Hameed, Wei Cao, Bahiga A. Mansour, Inas K. Elzawaway, El-Metwally M. Abdelrazek, Hani E. Elsayed-Ali
Applied Research Center Publications
Cu (In,Ga,Al)Se2 (CIGAS) thin films were studied as an alternative absorber layer material to Cu(InxGa1-x)Se2. CIGAS thin films with varying Al content were prepared by magnetron sputtering on Si(100) and soda-lime glass substrates at 350 °C, followed by postdeposition annealing at 520 °C for 5 h in vacuum. The film composition was measured by an electron probe microanalyzer while the elemental depth profiles were determined by secondary ion mass spectrometry. X-ray diffraction studies indicated that CIGAS films are single phase with chalcopyrite structure and that the (112) peak clearly shifts to higher 2θ …
A Combined Experimental-Numerical Approach For Determining Mechanical Properties Of Aluminum Subjects To Nanoindentation, Mao Liu, Cheng Lu, A Kiet Tieu, Ching-Tun Peng, Charlie Kong
A Combined Experimental-Numerical Approach For Determining Mechanical Properties Of Aluminum Subjects To Nanoindentation, Mao Liu, Cheng Lu, A Kiet Tieu, Ching-Tun Peng, Charlie Kong
Faculty of Engineering and Information Sciences - Papers: Part A
A crystal plasticity finite element method (CPFEM) model has been developed to investigate the mechanical properties and micro-texture evolution of single-crystal aluminum induced by a sharp Berkovich indenter. The load-displacement curves, pile-up patterns and lattice rotation angles from simulation are consistent with the experimental results. The pile-up phenomenon and lattice rotation have been discussed based on the theory of crystal plasticity. In addition, a polycrystal tensile CPFEM model has been established to explore the relationship between indentation hardness and yield stress. The elastic constraint factor C is slightly larger than conventional value 3 due to the strain hardening.