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Title: CONSTITUTIVE BEHAVIOR AND MODELING OF AL-CU ALLOY SYSTEMS
Creator: Turkkan, Omer Anil
Date: 2013-05-07, 2013-05
Description: High speed deformation events such as caused by projectile penetration, fragment impact and shock/blast loading are of great importance in...
Show moreHigh speed deformation events such as caused by projectile penetration, fragment impact and shock/blast loading are of great importance in designing materials and structures for army applications. In these events, materials are subjected to large strains, high strain rates and rapid increase in temperature due to thermoplastic heating. In such severe conditions, overall performance is determined by the evolution of flow stress, failure initiation and propagation, and commonly in the form of adiabatic shear banding. Some of 2XXX series aluminum-copper (Al-Cu) alloys are recognized for their decent ballistic properties, and therefore they have been used as an armor material for lightweight U.S. Army vehicles. Most recently, an Al-Cu-Mg-Mn-Ag alloy labeled as Al 2139-T8 has been developed and is evaluated by the U.S. Army Research Labs. because of its better ballistic properties and higher strength than its predecessors. The underlying microstructure is believed to be the key element for this superior performance. The goal of this study is to explore the effect of composition and microstructural features on overall dynamic material behavior by examining mechanical and deformation behavior of different Al-Cu material systems. Starting from the pure single crystal and polycrystalline Al structures, and adding a different element to chemical composition in each step (i.e., Cu, Mg, Mn, Ag), mechanical response of these different systems has been investigated. For all alloy systems with the exception of single crystal Al, mechanical tests have been performed at room and elevated temperatures covering quasi-static ( to ) and dynamic ( to strain rate regimes. xiv Shear-compression specimens promoting localized shear deformation have been used to explore tendency of each one of these materials to failure by adiabatic shear banding. In addition to phenomenological Johnson-Cook Model (JCM), physics based Zerrilli-Armstrong and Mechanical Threshold Models have been studied to model the constitutive response of Al-Cu alloys over a wide range of strain rates and temperatures.. An improved ZA model has been developed to better capture the trends in experimental data.
M.S. in MECHANICAL, MATERIALS, AND AEROSPACE ENGINEERING, May 2013
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Title: NATURAL AGING EFFECT ON DOUBLE AGED ALUMINUM ALLOY AA7075
Creator: Kara, Baris
Date: 2012-04-27, 2012-05
Description: The effect of natural aging (NA) on mechanical properties in double aged aluminum alloys, AA7075, was studied by means of hardness tests,...
Show moreThe effect of natural aging (NA) on mechanical properties in double aged aluminum alloys, AA7075, was studied by means of hardness tests, tensile tests and stress corrosion cracking (SCC) tests. Natural aging can strengthen AA7075 alloys after solution heat treatment, and reaching the stable condition can take years for the alloy. Double aging (DA) is very beneficial method in terms of energy savings and productivity because this method provides the peak hardness in a much shorter time compared to single aging, and DA treatment produces hardness, yield stress and tensile stress which are comparable with those produced by SA. In this study, the alloys were naturally aged for different times before double aging treatment, and the relationship between double aging treatment and natural aging treatment was observed. The results show that different natural aging times do not significantly affect the final mechanical properties of double aged alloys. Consequently, the loading time to aging furnace after solution heat treatment does not play an important role in the double aging treatment of AA7075 alloys.
M.S. in Materials Science and Engineering, May 2012
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Title: THE CORRELATION BETWEEN FATIGUE PROPERTY AND PORE MORPHOLOGY OF POWDER METALLURGY TI6AL4V
Creator: Yan, Yingjie
Date: 2012-12-12, 2012-12
Description: The microstructure and fatigue properties of sintered Ti-6Al-4V were investi- gated as a function of sintered density and pore morphology. A...
Show moreThe microstructure and fatigue properties of sintered Ti-6Al-4V were investi- gated as a function of sintered density and pore morphology. A quantitative analysis of microstructure was conducted to correlate with tensile and fatigue properties to understand the in uence of sintering density and pore morphology. Low cycle fatigue (LCF) using constant strain control was conducted at room temperature, R=-1 and sine waveform. High cycle fatigue (HCF) using constant stress control was conducted at room temperature, R=0.1 and sine waveform. It was found that there was no signi cant di erence in tensile strength but the fatigue endurance limit was increased by 20% when the sintering density was increased from 95% to 99%. Moreover, fatigue endurance limit was increased when the shape factor increased among three di er- ent sintering conditions(1010 -60min-690MPa, 1130 -90min-410MPa, 1250 -30min- 550MPa). Fracture surface analysis indicated that the fatigue crack initiated from the cluster of pore either at surface or at the sub-surface. The implication of pore morphology and porosity on mechanical behaviour and fatigue fracture of P/M Ti- 6Al-4V were discussed. It was estimated that the shape factor was 0.05 for A-50 and 0.07 for A-100, respectively. A polynomial relationship was found between the fatigue endurance limit and shape factor among three sintering con gurations. It was found that the PM parts with a higher shape factor had a higher fatigue endurance limit.
M.S. in Materials Science and Engineering, December 2012
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Title: Test of slender wooden struts for aeroplanes
Creator: Smith, M. A,, Kellener, W. A., Stevens, W. A.
Date: 2009, 1910
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testofslenderwoo00smit
Thesis (B.S.)--Armour Institute of Technology

Title: Study of the action of a four inch grinnell variable pressure alarm valve
Creator: Hotchkin, E. W., Pfaelzer, F. M
Date: 2009, 1910
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofactionoff00hotc
Thesis (B.S.)--Armour Institute of Technology, 1910 B.S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/studyofactionoff00hotc
Thesis (B.S.)--Armour Institute of Technology, 1910 B.S. in Fire Protection Engineering, 1910
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Title: COATING OF BORON NITRIDE THIN FILM ON TITANIUM
Creator: Huang, Mairui
Date: 2013, 2013-12
Description: To improve the wear resistance of titanium and extend its service life, coating boron nitride thin films on the surface of titanium matrix was...
Show moreTo improve the wear resistance of titanium and extend its service life, coating boron nitride thin films on the surface of titanium matrix was studied in this work. To obtain surface property enhancement, the samples were coated by isothermal sintering at 1000°C – 1400°C in a vacuum furnace for 2h, 4h or 6h. The microstructure of the thin film was investigated employing X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). To identify the composition of interlayers between BN and Ti, EDS analysis was run through the whole reaction zone. It showed that the BN was being consumed, titanium borides (TiB and TiB2), titanium nitride (TiN1-x), and solid solution of nitrogen in titanium (α-Ti (N)) layers formed at the interface between the BN coating and Ti matrix. Correspondingly, the XRD analysis indicated that TiB, TiB2, TiN, and α-Ti(N) phases were presented in good agreement with the EDS result. The layers grew fast in the sintering process which benefited from the fine grain size and highly oriented layers grown in the reaction zone. However, the well-known parabolic diffusional growth is only part of mechanisms for explaining the reactiondiffusion kinetics. The diffusion paths were obtained from the phase sequences at the interface between BN and Ti and thus could be represented on the isothermal section of the B-N-Ti ternary diagram. Moreover, the influence of the sintering temperature and the length of the actual sintering period on the layer sequences and thickness of the reaction zone were investigated. The micro-hardness test results showed that the Ti matrix with deposited BN thin films exhibited significant increased surface hardness. Obviously, the surface hardness xiii rose along with sintering temperature and holding time, and the hardness could be improved over 50%.
M.S. in Materials Science and Engineering, December 2013
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Title: Vacuum jacketing vs. steam jacketing
Creator: Gentry, T. E., Wernick, F. E.
Date: 2009, 1910
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/vacuumjacketingv00gent
Thesis (B.S.)--Armour Institute of Technology

Title: Tests on a four-cycle automobile engine
Creator: Barrett, D. O., Morgan, C. W.
Date: 2009, 1908
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testsonfourcycle00barr
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 1-3

Title: Study of ideal dry pipe valve
Creator: Hepp, A. A., Smith, E. J. L.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofidealdryp00hepp
Thesis (B.S.)--Armour Institute of Technology

Title: Steam jet ash conveyors
Creator: Himelblau, Harry
Date: 2009, 1919
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/steamjetashconve00hime
Thesis (B.S.)--Armour Institute of Technology

Title: FLOW DISTRIBUTION AND TURBULENCE CHARACTERISTICS IN AN URBAN ENVIRONMENT
Creator: Goudarzi, Sepehr Aboutorabi
Date: 2014, 2014-12
Description: The amount of the urban flow studies has been excessively increased during past decade. Pollutant dispersion quality has been the main...
Show moreThe amount of the urban flow studies has been excessively increased during past decade. Pollutant dispersion quality has been the main motivation in these investigations. Besides, a more recent goal is to provide a spatial map of the flow distribution which can be used for micro aerial vehicles (MAV) flight control. These all have developed advanced methodologies in both computational and experimental researches. In this study flow distribution and characteristics are investigated in a 7×5 urban array model (blocks are representing buildings) in a low-speed wind tunnel. Stereoscopic Particle Image Velocimetry (SPIV) is employed as the velocimetry method to acquire three-dimensional velocity filed in the three-dimensional region of street areas. A large amount of SPIV data was acquired in four consecutive streets for four wind incidence angle. The evolution of the three-dimensional coherent structures is investigated. Also, flow characteristics are studied using parameters such as mean velocity, turbulent kinetic energy (TKE), vorticity magnitude and Reynolds stress tensor components. All flow characteristics are studied in four consecutive streets of the array. Also, the effects of the wind direction on the flow characteristics and arch vortex location are studied. A valuable achievement of this study is to suggest a method to find the location of the arch vortex legs, and find the angle between the arch horizontal axis with the spanwise direction (𝜑). It is shown that this angle is increasing significantly in variation of angle of incidence (AOI) in the range of 𝐴𝑂𝐼=0° to 𝐴𝑂𝐼=15°. The rate of increment of 𝜑 is much slower between 𝐴𝑂𝐼=15° and 𝐴𝑂𝐼=30° but the 𝜑 range is still greater than AOI. Existence of geometrical symmetry in 𝐴𝑂𝐼=0° case, brings unique features for this condition such as zero spanwise flow velocity in streets.. Increasing AOI to higher magnitudes will cause severe change in flow distribution and turbulence level, in the sense that turbulence intensity starts to impoverish.
M.S. in Mechanical and Aerospace Engineering, December 2014
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Title: A study of water distribution from automatic sprinklers
Creator: Schmidt, J. L., Alling, C. R
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofwaterdist00schm
Thesis (B.S.)--Armour Institute of Technology, 1907 B. S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/studyofwaterdist00schm
Thesis (B.S.)--Armour Institute of Technology, 1907 B. S. in Fire Protection Engineering, 1907
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Title: A system of automatic train control
Creator: Morgan, Charles Woodward
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/systemofautomati00morg
Thesis (B.S.)--Armour Institute of Technology, 1911 Includes bibliographical references...
Show morehttp://www.archive.org/details/systemofautomati00morg
Thesis (B.S.)--Armour Institute of Technology, 1911 Includes bibliographical references and index B.S. in Mechanical Engineering, 1911
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Title: THERMAL AND FLUID FLOW FEASIBILITY STUDY OF A CIRCULAR COUETTE FLOW REACTOR VIA PLANAR LASER-INDUCED FLUORESCENCE IMAGING
Creator: Bittner, Peter R.
Date: 2012-04-28, 2012-05
Description: Liquid fueled microcombustors face many challenges in their development, the most prominent being high temperature gradients and radiative...
Show moreLiquid fueled microcombustors face many challenges in their development, the most prominent being high temperature gradients and radiative effects. Because the walls of microcombustors are thin, they offer very little resistance to conductive heat transfer, regardless of the materials used. This can cause very high heat losses that lead to large temperature gradients in the gas compared to nearly uniform temperatures inside conventional combustion chambers. In this investigation a circular Couette flow reactor (CCFR) and planar laser induced fluorescence (PLIF) are used to examine the feasibility of studying vapor distributions of a monodisperse acetone droplet stream, formed by a vibrating orifice aerosol generator (VOAG), exposed to combinations of varying velocity gradients, temperature gradients and radiant heating. The acetone droplets are injected through various ports on the CCFR to vary the time for vaporization of the droplets inside the reactor. Initial results of the operating CCFR uses acetone droplets seeded into the test section to demonstrate the fluorescence of the liquid and vapor acetone within the test section.
M.S. in Mechanical, Materials, and Aerospace Engineering, May 2012
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Title: SIMULATIONS OF CENTERLINE DEFECT CLOSURE IN OPEN DIE FORGING
Creator: Gangatirkar, Suhasini
Date: 2014, 2014-12
Description: Open die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often...
Show moreOpen die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often have internal defects such as porosity, shrinkage cavities which damage the overall quality of the final product and affect the mechanical properties of the material. The voids developed during cooling of the ingot have to be treated in the initial forming operation known as cogging which depends on parameters such as die width ratio, die overlap, feed ratio, die shape etc. In this work, finite element method has been used to identify different aspects affecting centerline defect closure, material properties, effect of friction coefficient, relationship between effective strain and the grain size. FORGE 2011 and FORGE NxT 1.0 by Transvalor Corp were used to create numerical models. The material used in this case is H13. Material data and compression test samples were obtained from experiments in a Gleeble 3500. Physical experiments carried out on the Gleeble 3500 were used to determine the coefficient of friction for samples treated at different temperature, strain and strain rates. The effect of these parameters on coefficient of friction was studied in later part of the study. The formulae from the literature used to calculate the coefficient of friction was validated by using simulation models of the compression test samples. These samples were also used to study fraction recrystallized for a particular sample to study the relationship between effective strain and microstructure. Comparisons between validation experiments and simulations showed that there was good agreement between the two and established the effective strain criterion for void closure. From the conclusions obtained from validation experiments, optimal pass schedule was developed to ensure closure of internal voids and uniform distribution of effective strain along centerline for sound quality of the workpiece by changing die overlap percentage every two passes.
M.S. in Material Science Engineering, December 2014
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Title: A study of anti-friction lineshaft bearings
Creator: Katzinger, Arthur, Alte, Arthur S.
Date: 2009, 1916
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofantifrict00katz
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 212-220

Title: The study and design of spray nozzles as applied to the De La Vergne oil engine
Creator: Harman, William E. S, Ward, Fred L
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studydesignofspr00harm
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 2

Title: DISCONTINUOUS IN THE NI-CO-AL PRECIPITATION ALLOY SYSTEM
Creator: Liu, Tian
Date: 2014, 2014-05
Description: The synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments,...
Show moreThe synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments, such as heat treatment, cold rolling, and electrolytic etching, have been performed to develop the desired microstructure. Nanostructured materials have great potential in a number of applications, such as catalysis, light weight structural materials, thermal management and pollution reduction. Kinetic information of the Ni-Co-Al alloy was obtained through measuring the optical micrographs of samples aged at di erent temperatures. The morphology of the nanostructure of the Ni-Co-Al alloy was investigated using scanning electron microscopy (SEM). The mechanical property (hardness) of the Ni-Co-Al alloy was obtained in di erent conditions as well. The Ni-Co-Al alloys were recrystallized in di erent ways. The texture of the alloys were determined using electron backscattered di raction (EBSD). After analyzing those experimental results, we nd that the discontinuous precipitation goes to completion in the Ni-Co-Al alloy. The discontinuous precipitates present a lamellar structure. The size of plates is similar with the spacing between plates and achieves a nanoscale architecture. The TTT curve of the Ni-Co-Al alloy with a composition of 43 at.% Ni, 48 at.% Co and 9 at.% Al provides abundant kinetic information. Further work is needed to produce a strong cube texture ((100) planes parallel to the foil surface).
M.S. in Materials Engineering, May 2014
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Title: PARAMETRIC COST ESTIMATION MODEL OF INTEGRATED REACTOR VESSEL UNDER MODULAR CONSTRUCTION WITHIN A FACTORY ENVIRONMENT
Creator: Chen, Xuan
Date: 2013, 2013-12
Description: High initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem...
Show moreHigh initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem because they have a much smaller financial barrier. In this thesis, parametric cost estimation modeling studies have been performed for the SMR integrated reactor vessel (IRV) under a factory environment. Based on different prior fabrication experiences, three scenarios have been studied, and the corresponding possible manufacturing costs of the entire IRV and its subcomponents have been estimated. To explore the cost allocation, the total cost has been divided into five cost contributors: labor, material, tooling labor, tooling replacement, and other. The results have been analyzed and discussed.
M.S. in in Mechanical, Material and Aerospace Engineering, December 2013
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Title: Tests on Kerr steam turbine and direct-connected Worthington centrifugal pump
Creator: James, Sydney Vincent, Jackson, Irving Foster
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testsonkerrsteam00jame
Thesis (B.S.)--Armour Institute of Technology; Includes index

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