| Bulk Nanocomposite LaCo5/LaCo13 Magnets (POSTPRINT) |
Aug 2012 |
5 pages |
| Authors:
Yuhui Shen; Zafer Turgut; Meiqing Huang; John Horwath; DAYTON UNIV OH RESEARCH INST
|
 | The effects of processing parameters and composition on the magnetic properties and microstructure of nanocrystalline La-Co-based hard magnetic materials were investigated. Bulk nanocomposite LaCo5/LaCo13 magnets were fabricated by mechanical alloying of LaCo5 and La2Co7 powder mixtures and subsequent hot pressing at 580-810 deg C. A high coercive field (Hc) of over 16 kOe with a smooth demagnetization curve was obtained in a composition range of 25-30 wt. % La2Co7 when ... |
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| Quick Reaction Evaluation of Materials and Processes (QRE). Task Order 0008: Titanium Billet Characterization and Materials Properties Development (Nonconforming Titanium) - Executive Summary |
Jan 2012 |
368 pages |
| Authors:
John J Ruschau; Nicholas J Jacobs; Steven R Thompson; DAYTON UNIV OH RESEARCH INST
|
| A previous federal investigation identified a risk associated with improperly processed titanium (Ti) material being used in the fabrication of critical components in several USAF and DoD systems. To investigate the potential for major mishaps, a USAF Titanium Task Force was formed to further define risk to USAF systems and to assist with mitigation efforts. An R&D testing program was designed to develop reasonable lower bound property data on a ... |
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| Understanding the Science Behind How Methylene Chloride/Phenolic Chemical Paint Strippers Remove Coatings |
Oct 2011 |
88 pages |
| Authors:
John L Graham; Takahiro Yamada; DAYTON UNIV OH RESEARCH INST
|
| The objective of this program was to obtain a sound understanding of how methylene chloride/phenol-based (MC/P) paint strippers function by understanding the specific roles of the primary paint stripping components; methylene chloride, phenol, ethanol, and water. This was accomplished through s series of tasks including sample selection, conceptual and computational molecular modeling, infrared spectroscopy, measurements of volume swell, the extent and rate of debonding and the analysis of the solvent ... |
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| Evaluation of Fuzzy Fiber Sensors for Structural Health Monitoring |
Nov 2010 |
54 pages |
| Authors:
Michael Bouchard; Khalid Lafdi; Norman Schehl; James Sebastian; Yuhchae Yoon; DAYTON UNIV OH RESEARCH INST
|
| As advanced fiber composites are utilized more frequently in primary structural applications, there is a key challenge to enhance the performance and reliability while reducing maintenance. As a consequence, there is tremendous scientific and technical interest in the development of techniques for monitoring the health of composite structures where real-time sensing can provide information on the state of chemistry and micro-structural damage. In this study, it has been established that ... |
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| POWER AND THERMAL TECHNOLOGIES FOR AIR AND SPACE-SCIENTIFIC RESEARCH PROGRAM Delivery Order 0018: Single Ion Conducting Solid-State Lithium Electrochemical Technologies (Task 4) |
Aug 2010 |
70 pages |
| Authors:
Sarwan S Sandhu; DAYTON UNIV OH RESEARCH INST
|
| A theory-based mathematical model has been developed to quantitatively describe the electrokinetic and transport processes that take place in a lithium-based cell/battery during its operation. Future numerical simulation, based on the presented model formulation, of a lithium-based cell/battery is expected to provide the quantitative information for rapid cell/battery construction and experimental work. Performance of an operating cell/battery of a given design can also be predicted using the presented formulation. |
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| Interaction of Elastic Waves with Corrosion Damage |
Aug 2010 |
7 pages |
| Authors:
Eric D Swenson; Martin P Desimio; Steven E Olson; Hoon Sohn; DAYTON UNIV OH RESEARCH INST
|
| Corrosion inspection and repair accounts for 21% of the total maintenance costs averaged over the Army, Navy, and Marine air and ground vehicles. A reliable automated method for inspection can lead to cost reductions due to avoiding unnecessary tear down and re-assembly. Elastic waves can travel across relatively large distances in plate-like structures and are affected by the presence of corrosion. This paper presents an investigation of the interaction of ... |
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| Studying the Effect of Residual Stresses on Fatigue Cracks Through Full-Field Methods (PREPRINT) |
Apr 2010 |
9 pages |
| Authors:
David A Johnson; Dennis J Buchanan; Reji John; DAYTON UNIV OH RESEARCH INST
|
| In this effort, a corner crack was grown from a notch in a nickel-based superalloy specimen with a shot-peened surface treatment to induce residual stresses. The crack length was less than 200 microns, and the full displacement field near the crack was determined using advanced digital image correlation. The specimen was then annealed at elevated temperatures to reduce or eliminate the residual stresses, and the full displacement field near the ... |
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| The Effect of Diethylene Glycol Monomethyl Ether (DiEGME) on Microbial Contamination of Jet Fuel: A Minimum Concentration Study |
Mar 2010 |
46 pages |
| Authors:
Lori M Balster; Marlin D Vangsness; Loryn L Bowen; Susan S Mueller; Lisa M Brown; Ellen M Strobel; DAYTON UNIV OH RESEARCH INST
|
| Diethylene glycol monomethyl ether (DiEGME) is widely used in military aircraft to inhibit both fuel system icing and microbial growth. However, due to the cost of this additive and its deleterious effects of the additive, a study is being conducted to determine if it is possible to reduce the concentration of DiEGME in military aircraft fuel. The study presented here was conducted to support the larger study investigating the possible ... |
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| POWER AND THERMAL TECHNOLOGIES FOR AIR AND SPACE - SCIENTIFIC RESEARCH PROGRAM Delivery Order 0015: High Performance Permanent Magnets |
Mar 2010 |
46 pages |
| Authors:
Christina Chen; DAYTON UNIV OH RESEARCH INST
|
| Advanced permanent magnetic materials are in high demand by the Air Force. Developing high-performance nanomagnetic materials was the focus of this program. Methods for making anisotropic bulk nanocomposite magnets of Nd-Fe-B/Fe-Co, as well as Sm-Co/Co-Fe, were investigated, through which we gained comprehensive understanding in developing advanced magnetic nanocomposites. Several key challenges were identified, which include limiting oxidation during synthesis of the nanopowders, uniformly dispersing the two phases, maintaining the two ... |
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| Growth of High Quality Carbon Nanotubes on Free Standing Diamond Substrates |
Jan 2010 |
16 pages |
| Authors:
C Varanasi; J Petry; L Brunke; B T Yang; W Lanter; J Burke; H Wang; J S Bulmer; J Scofield; Barnes; N P; DAYTON UNIV OH RESEARCH INST
|
| Carbon nanotubes (CNTs) were grown on diamond-coated Si substrates and free-standing diamond wafers to develop efficient thermal interface materials for thermal management applications. High quality, translucent, free-standing diamond substrates were processed in a 5 kW microwave plasma chemical vapor deposition (CVD) system using CH4 as precursor. Ni and Ni-9%W-1.5% Fe catalyst islands were deposited to nucleate CNTs directly onto the diamond substrates. Randomly-oriented multi-walled CNTs forming a mat of tilde ... |
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| Power and Thermal Technologies for Air and Space-Scientific Research Program. Delivery Order 0017: Study of Microchip Power Module Materials Using Mini-Channel Heat Exchanger |
Dec 2009 |
102 pages |
| Authors:
Andrew Cole; Jamie Ervin; Larry Byrd; DAYTON UNIV OH RESEARCH INST
|
| An apparatus to simulate the cooling of a silicon carbide (SiC) metal oxide semiconductor field excited transistor (MOSFET) using a mini-channel heat exchanger with a single phase (liquid) fluid was constructed. The chip was simulated with a sample of SiC that is heated on one surface and cooled on the opposing surface using a mini-channel heat exchanger. One goal of this work was to demonstrate that the apparatus has the ... |
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| Quick Reaction Evaluations of Materials and Processes. Delivery Order 0005: Effects of Several Paint Removal Technologies on the Static and Fatigue Properties of Thin Aerospace Structural Materials |
Aug 2009 |
55 pages |
| Authors:
John J Ruschau; Patricia Youngerman; DAYTON UNIV OH RESEARCH INST
|
| An evaluation was conducted to ascertain the influence of paint removal technologies designed for use on thin skin aerospace structures, as well as to provide a sound database for future comparisons of other new and existing paint strip technologies. Materials evaluated were 2024-T3 sheet, both bare and clad, 7075-T6 sheet, thin skin aluminum honeycomb panels, and to a limited extent, polymeric composite sheet. The paint removal technologies examined include a ... |
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| Measurement of Apparent Temperature in Post-Detonation Fireballs Using Atomic Emission Spectroscopy |
May-2009 |
|
| Authors:
W K Lewis; C G Rumchik; DAYTON UNIV OH RESEARCH INST
|
 | The energy release dynamics of explosives are of ongoing interest, but the short timescales involved often limit the measurements that can be made during these processes. We have used atomic emission spectroscopy to measure the temperature of fireballs resulting from detonation of charges of Hexahydro-1,3,5-trinitro-1,3,5-triazine doped with barium nitrate. The time-averaged emission spectra indicate an apparent temperature of 3000 K, in good agreement with theoretical predictions. The technique demonstrated herein ... |
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| High Performance Polymer Film Dielectrics for Air Force Wide-Temperature Power Electronics Applications (Preprint) |
Feb 2009 |
19 pages |
| Authors:
Narayanan Venkat; Victor K McNier; Bang-Hung Tsao; Thuy D Dang; Jennifer N DeCerbo; Jeffery T Stricker; DAYTON UNIV OH RESEARCH INST
|
| Air Force currently has a strong need for the development of compact capacitors which are mechanically robust and thermally stable for operation in a variety of aerospace power conditioning applications. These applications demand better reliability and flexibility in the power system design as well as decreased thermal load for electronic system cooling. While power conditioning capacitors typically use polycarbonate (PC) dielectric films in wound capacitors for operation from -55 deg ... |
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| Dependence of Fuel Properties During Blending of Iso-Paraffinic Kerosene and Petroleum-Derived Jet Fuel |
Nov 2008 |
72 pages |
| Authors:
Richard Striebich; Linda Shafer; Matthew J DeWitt; Zachary West; Tim Harrison Edwards; William III; DAYTON UNIV OH RESEARCH INST
|
| The studies and analysis performed in this report were made to improve the understanding of blending an Iso-Paraffinic Kerosene (IPK) produced from natural gas via Fischer-Tropsch (FT) synthesis with several petroleum-derived fuels on the resulting chemical, physical and Fit-For-Purpose (FFP) properties. The IPK had a similar distillation range to a typical jet fuel and high iso-/normal alkane ratio. Blending showed a linear dependence in the specification and non-specification properties with ... |
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| A Coupled Creep Plasticity Model for Residual Stress Relaxation of a Shot Peened Nickel-Base Superalloy (Postprint) |
Sep-2008 |
12 pages |
| Authors:
Reji John; Dennis J Buchanan; Robert A Brockman; Andrew H Rosenberger; DAYTON UNIV OH RESEARCH INST
|
| Shot peening is a commonly used surface treatment process that imparts compressive residual stresses into the surface of metal components. Compressive residual stresses retard initiation and growth of fatigue cracks. During the component loading history, loading, or during elevated temperature static loading, such as thermal exposure and creep. In these instances, taking full credit for compressive residual stresses would result in a methodical approach for characterizing and modeling residual stress ... |
|
| Evaluation and Testing of the Suitability of a Coal-Based Jet Fuel |
Jun 2008 |
72 pages |
| Authors:
X Zabarnick; D K Phelps; Z J West; L S Shafer; J S Ervin; M J DeWitt; K E Binns; T F Williams; G L Dieterle; L M Balster; Harrison; W E III; DAYTON UNIV OH RESEARCH INST
|
| A candidate coal-based fuel was evaluated both for use as substitute for conventional petroleum-derived JP-8 fuel and as a candidate for advanced application. Numerous properties and performance behavior were monitored through a combination of specification tests and research-type evaluations. This testing included a variety of physical and chemical property tests in the areas of high temperature thermal stability, low temperature flowability, and combustion emissions characteristics, as well as a thorough ... |
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| Organizational Effectiveness in the Tanker Airlift Control Center |
01-May-2008 |
35 pages |
| Authors:
Laura G Militello; Anne K Offner; Greg Padula; Stephanie D Swindler; Joseph B Lyons; DAYTON UNIV OH RESEARCH INST
|
| The Tanker Airlift Control Center (TACC) controls more than 1200 aircraft and over 600 missions across 50 countries per day. This complex organization organically adapts to a constantly changing set of missions including wartime efforts, humanitarian relief, response to natural disasters, presidential movement, and many others. As such, the TACC represents a particularly fertile ground for studying organizational change. The research team drew from management and psychology literatures, and from ... |
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| Deep Defect Detection within Thick Multilayer Aircraft Structures Containing Steel Fasteners Using a Giant-Magneto Resistive (GMR) Sensor (Preprint) |
OCT 2007 |
10 pages |
| Authors:
Ray T. Ko; Gary J. Steffes; DAYTON UNIV OH RESEARCH INST
|
| Defect detection within thick multilayer structures containing steel fasteners is a challenging task in eddy current testing due to the magnetic permeability of the fasteners and overall thickness of the structure. To address these issues, a magnet is applied to the fasteners during the inspection to reduce the noise caused by the permeability. Using a GMR sensor coupled with a lock-in amplifier to increase eddy current sensitivity, data is obtained ... |
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| Resonant Frequency Eddy Current Liftoff Measurements for Shot Peening Intensity Assessment in Materials (Preprint) |
JUL 2007 |
10 pages |
| Authors:
Ray T. Ko; Mark P. Blodgett; Shamachary Sathish; Thomas R. Boehnlein; DAYTON UNIV OH RESEARCH INST
|
| The shot peening intensity of nickel base materials has been examined with an innovative eddy current measurement. The goal is to provide a nondestructive tool to quantitatively evaluate the surface conditions after shot peening. Traditionally, the residual stress caused by the shot peening process can be examined by X-ray diffraction. Recent eddy current works have shown promising results in evaluating the small conductivity variation due to the residual stress. This ... |
|
| A Coupled Creep-Plasticity Model for Residual Stress Relaxation of a Shot-Peened Nickel-Base Superalloy |
MAY 2007 |
122 pages |
| Authors:
Dennis J. Buchanan; DAYTON UNIV OH RESEARCH INST
|
| Shot peening has been employed in numerous industries for decades to impart beneficial compressive residual stresses on the surface of metal components. Compressive residual stresses retard initiation of surface cracks and therefore improve fatigue resistance and fatigue life. For elastic conditions, accurate fatigue life predictions, including credit for residual stresses, are possible for complex geometries with complicated load histories. For inelastic material behavior, shot-peened residual stresses may change continuously under ... |
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| Nanocomposites Derived from Carbon Nanofibers and a Hyperbranched Poly(Ether-Ketone): In Situ Polymerization, Chain-End Modification, and Properties (Preprint) |
MAY 2007 |
41 pages |
| Authors:
David H. Wang; Peter Mirau; Loon-Seng Tan; Bing Li; Christopher Y. Li; Jong-Beom Baek; DAYTON UNIV OH RESEARCH INST
|
| 5-Phenoxyisophthalic acid, an A2B monomer, was easily polymerized via a Friedel-Crafts acylation in poly(phosphoric acid)/phosphorus pentoxide (PPA/P2O5; 1:4 w/w) medium to form a CO2H-terminated hyperbranched poly(ether-ketone), HPB-PEK. Thus, the polymerization of 5-phenoxyisophthalic acid, in the presence of various amounts (1, 2, 5, 10, 20, 30 and 40 wt%) of vapor-grown carbon nanofibers (VGCNF) was performed under similar reaction conditions. The resulting (HPB-PEK)-g-VGCNF nanocomposites were insoluble in dichlorobenzene or toluene, but ... |
|
| Development of Improved and Novel Thermal Control Coatings (Preprint) |
MAY 2007 |
13 pages |
| Authors:
Amber I. Davis; Clifford A. Cerbus; Joel A. Johnson; DAYTON UNIV OH RESEARCH INST
|
| Thermal control coatings (TCCs) play a critical role in the thermal management of space assets through the reflection of incident solar energy and emittance of infrared heat. The development of new thermal control coatings with improved solar energy reflection, infrared emittance, and reduced weight are essential to the design of future space assets that will reside in harsh environments and have increasing constraints on weight. Optimization of pigment particle size ... |
|
| Tensile Failure Prediction and Measurement in Composite Scarf Repair (Preprint) |
MAY 2007 |
10 pages |
| Authors:
Endel V. Iarve; Timothy D. Breitzman; Benjamin M. Cook; Gregory A. Schoeppner; David H. Mollenhauer; DAYTON UNIV OH RESEARCH INST
|
| Oversized quasi-isotropic tensile specimens were manufactured from IM6/3501-6 graphite/epoxy prepreg. Seven specimens were scarfed in the center of the panel, and four of the panels were subsequently repaired. The repair patch consisted of a ply-by-ply replacement of the removed material with a FM-300M095 film adhesive placed between the repair patch and the scarfed specimen. The patch and adhesive were then co-cured. The repaired and unrepaired specimens were strain gaged and ... |
|
| Image Reconstruction Based Modeling of 3D Textile Composite (Postprint) |
APR 2007 |
22 pages |
| Authors:
Eric Zhou; David Mollenhauer; Endel Iarve; DAYTON UNIV OH RESEARCH INST
|
| Innovative weaving and braiding processes open up a new opportunity for making 3-D textile composites that give significantly damage-tolerant structural response with design flexibility for durable joints, near-net shape processing, etc. To fully understand the mechanical behavior of 3-D textile composites, it is essential to perform analyses to predict effective material properties and damage initiation and growth. In this paper we present a new approach to generating 3-D textile composite ... |
|
| Room-Temperature, Near IR Fluorescence of High Optical Quality KTP (Postprint) |
APR 2007 |
10 pages |
| Authors:
S. M. Hegde; K. L. Schepler; R. D. Peterson; D. E. Zelmon; DAYTON UNIV OH RESEARCH INST
|
| We investigated room temperature fluorescence in the 500-900nm spectral region from high optical quality, polished and uncoated KTP crystals from three different commercial vendors. The crystals were all cut into 5x5x5 mm3 cubes with their dielectric axes along the cube edges. The pump source was a tripled Nd:YAG laser operating at 355nm and 7mJ energy having 3ns pulse width and 100Hz pulse repetition rate. Samples from two vendors showed low ... |
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| Quantification of Impact Damage in CMC Thermal Protection Systems Using Thin-Film Piezoelectric Sensors (Preprint) |
MAR 2007 |
12 pages |
| Authors:
Samuel J. Kuhr; James L. Blackshire; DAYTON UNIV OH RESEARCH INST
|
| Thermal protection systems (TPS) are frequently subjected to impacts from micrometeoroids and ground handling during refurbishment. The damage resulting from such impacts can greatly reduce the vehicle's overall ability to resist extreme temperatures. Therefore, it is essential to have a reliable method to detect and quantify the damage resulting from impacts. In this effort, the effectiveness of lightweight thin film piezoelectric sensors was evaluated for impact detection and quantification in ... |
|
| E-Beam-Cured Layered-Silicate and Spherical Silica Epoxy Nanocomposites (Preprint) |
Mar 2007 |
26 pages |
| Authors:
Chenggang Chen; David P Anderson; DAYTON UNIV OH RESEARCH INST
|
| This research demonstrates than an epoxy nanocomposite can be made through electron beam (e-beam) curing. The nanofillers can be two dimensional (layered-silicate) and zero dimensional (spherical silica). Both the spherical silica epoxy nanocomposite and the layered-silicate epoxy nanocomposite can be cured to a high degree of curing. The transmission electron microscopy (TEM) and small-angle x-ray scattering (SASX) of the e-beam-cured layered-silicate epoxy nanocomposites demonstrate the intercalated nanostructure or combination of ... |
|
| Investigation of Bond Quality Effects on Piezoelectric Sensing of Impact Damage (Preprint) |
Mar 2007 |
11 pages |
| Authors:
Jeong K Na; James L Blackshire; DAYTON UNIV OH RESEARCH INST
|
| Elastic waves generated by foreign materials impacting surfaces of aerospace vehicle can be used to detect and quantify the severity of damage. Passive acoustical emission sensors, made of piezoelectric elements, are typically used as impact signal detection devices. In this study, we have concentrated on characterizing the bonding qualities of piezoelectric sensors in terms of various bonding materials and adhesion conditions such as bond strength, bond stiffness, partial bonding, and ... |
|
| Atomic Force Microscopy Based Eddy Current Imaging and Characterization of Composite and Nanocomposite Materials (Preprint) |
Mar 2007 |
12 pages |
| Authors:
Vijayaraghava Nalladega; Shamachary Sathish; Don Klosterman; Kumar V Jata; Mark P Blodgett; DAYTON UNIV OH RESEARCH INST
|
| Atomic Force Microscope (AFM) based eddy current imaging technique has been used to characterize carbon fiber reinforced composites and carbon nanofibers nanocomposite. The surface topography and eddy current images of the same region of the sample acquired at the same time are presented. While the contrast in AFM images is due to surface topography variations, the contrast in the eddy current images is due to the local variation in the ... |
|
| Power and Thermal Technology for Air and Space-Scientific Research Program Delivery Order 0003: Electrical Technology Component Development |
Mar 2007 |
67 pages |
| Authors:
Bang-Hung Tsao; Jacob Lawson; DAYTON UNIV OH RESEARCH INST
|
| The goals of this delivery order were to study and develop materials, processes, and techniques for use in the fabrication of high-performance power electronic devices used in power management and control equipment and systems, which will be capable of operating in extreme environments in aircraft and on space platforms. |
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| Detection of Localized Heat Damage in a Polymer Matrix Composite by Thermo-Elastic Method (Preprint) |
FEB 2007 |
16 pages |
| Authors:
John Welter; Shamachary Sathish; Erik Ripberger; Eric Lindgren; DAYTON UNIV OH RESEARCH INST
|
| Reduction of strength of polymer matrix composites when exposed to high temperatures is a major concern in aerospace industry. Loss of mechanical strength can be measured only through established destructive techniques; there is a need for detection and evaluation of heat damage in PMC. This paper describes a thermo-elastic based non-contact nondestructive technique for detection and evaluation of heat damage in PMC. The efficiency of the material to convert acoustic ... |
|
| Stoichiometry and Characterization of Aluminum Oxynitride Thin Films by Ion-Beam-Assisted Pulsed Laser Deposition (Preprint) |
JAN 2007 |
23 pages |
| Authors:
J. S. Zabinski; J. J. Hu; J. E. Bultman; N. A. Pierce; A. A. Voevodin; DAYTON UNIV OH RESEARCH INST
|
| Oxides are inherently stable in air at elevated temperatures and may serve as wear resistant matrices for solid lubricants. Aluminum oxide is a particularly good candidate for a matrix because it has good diffusion barrier properties and modest hardness. Most thin film deposition techniques that are used to grow alumina require high temperatures to impart crystallinity. Crystalline films are about twice as hard as amorphous ones. Unfortunately, the mechanical properties ... |
|
| Infrared Damage Detection System (IDDS) for Real-Time, Small-Scale Damage Monitoring |
JAN 2007 |
9 pages |
| Authors:
George A. Hartman; DAYTON UNIV OH RESEARCH INST
|
| Macroscopic damage and final failure of components subjected to repeated loading is preceded by microscopic damage accumulation in localized areas of the component material. The microscopic damage accumulation phase often comprises the majority of the life of the component. Thus, a detailed understanding of the processes involved would be invaluable for material design and life prediction. In metals, these localized damage accumulation areas are usually on the scale of the ... |
|
| Nanocomposites Derived From a Low-Color Aromatic Polyimide (CP2) and Amine-Functionalized Vapor-Grown Carbon Nanofibers: In Situ Polymerization and Characterization (Preprint) |
JAN 2007 |
55 pages |
| Authors:
David H. Wang; Michael J. Arlen; Jong-Beom Back; Richard A. Vaia; Loon-Seng Tan; DAYTON UNIV OH RESEARCH INST
|
| Vapor-grown carbon nanofibers (VGCNF) were functionalized with amine-containing pendants via a Friedel-Crafts acylation reaction with 4-(3-aminophenoxy)benzoic acid. The resulting H2N-VGCNF with ca. 5 atom% functionaliztion was in attendance during the polymerization of 2,2-bis(phtalic anhydride)-1,1,1,3,3,3-hexafluoroisopropane (6FDA) and 1,3-bis(3-aminophenoxy)benzene (APB) in N,N-dimethylacetamide (DMAc) to afford a series of polyimide (CP2)-based nanocomposite films, which contained 0.1 to 5.0 wt% of H2N-VGCNF. For comparison purposes, the pristine VGCNF (0.1-5.0 wt%) was also used in ... |
|
| The Effect of As-Large-As (ALA) Grains on the High-Temperature Fatigue Life of Waspaloy |
DEC 2006 |
120 pages |
| Authors:
Mandy L. Brogdon; DAYTON UNIV OH RESEARCH INST
|
| Waspaloy is a nickel superalloy that, when processed, may contain as-large-as (ALA) grains in the outer surface of the billet. Many components were manufactured containing this ALA region. The common practice now is to remove the ALA-affected region; however, the effect of these ALA grains in Waspaloy has not directly been studied. To characterize the material and determine the effects of the ALA grains, tensile tests and fatigue tests were ... |
|
| Off-Axis Creep Behavior of Oxide/Oxide Nextel(Trademark)720/AS-0 (Preprint) |
NOV 2006 |
23 pages |
| Authors:
Dennis J. Buchanan; Reji John; Larry P. Zawada; DAYTON UNIV OH RESEARCH INST
|
| Oxide/Oxide Ceramic Matrix Composites (CMC) are currently being demonstrated in high-temperature aerospace applications where their oxidation resistance is critical to a successful design. Many applications are engine components that are axisymmetric in shape and subject to axisymmetric thermal and mechanical loadings. Traditionally woven CMC materials used in these components are typically made from 0 deg/90 deg fiber architectures. In many cases the highest stresses are not always coincident with the ... |
|
| The Effect of Hard Coated Metals on the Thermo-Oxidative Stability of a Branched Perfluoropolyalklyether Lubricant (Preprint) |
OCT 2006 |
39 pages |
| Authors:
Patrick T. Hellman; Jeffrey S. Zabinski; Lois J. Gschwender; Carl E. Snyder; Andras L. Korenyi-Both; DAYTON UNIV OH RESEARCH INST
|
| M-50 and carburized Pyrowear 675(registered) steel coupons deposited with commercially available physical vapor deposited (PVD) TiN, TiCN, TiAlCN, TiCrCN/TiB4C multilayer, electroless Ni (E-Ni) TiN, and E-Ni TiCN coatings were immersed in a branched perfluoropolyalklyether (PFPAE), Krytox AC(registered), in an oxidative environment at temperatures ranging from 315 to 360 deg C for a duration of 24 hours and compared to uncoated coupons. Coated and uncoated Pyrowear 675(registered) coupons demonstrated superior corrosion ... |
|
| Power and Thermal Technology for Air and Space. Delivery Order 0006: Nano-filled Polymers for Electrical Insulation |
OCT 2006 |
17 pages |
| Authors:
Donald A. Klosterman; Mary Galaska; DAYTON UNIV OH RESEARCH INST
|
| The objective of this delivery order was to conduct research aimed at developing nano-filled polymers for electrical insulation. Improved polymers could be used in wiring, cabling, potting compounds, and capacitors. Specifically, this effort involved research in areas such as nano-filler dispersion, bulk sample fabrication, and thin film processing. These activities are designed to contribute to the improvement of highly stressed electrical insulation with a goal of improved mean time before ... |
|
| Quick Reaction Evaluation of Materials and Processes. Delivery Order 0010: Bonded Boron Patch Repair Evaluation |
SEP 2006 |
62 pages |
| Authors:
Nick J. Jacobs; DAYTON UNIV OH RESEARCH INST
|
| The C-141 weep-hole repair, performed in the early 1990s, was the first widespread application of a bonded boron composite repair on a critical structure. This program involved the evaluation of the residual strength and integrity of the bonded boron repairs from aircraft that were decommissioned and to be scrapped. A total of 67 residual strength tests were performed, including 54 original bonded boron composite repaired specimens, 4 new bonded repair ... |
|
| Corner Crack Propagation in the Presence of Residual Stresses (Preprint) |
MAY 2006 |
12 pages |
| Authors:
A. L. Hutson; M. Huelsman; D. Buchanan; R. John; S. Haering; DAYTON UNIV OH RESEARCH INST
|
| BA technology development program known as Engine Rotor Life Extension (ERLE) has been initiated by the United States Air Force. One of the key technologies being assessed under the ERLE program is the analysis of 3D crack propagation at critical locations in turbine engine components. These critical locations are typically shot peened requiring the ability to predict 3D crack propagation at stress concentration sites in the presence of residual stresses. ... |
|
| Beamforming of Lamb Waves for Structural Health Monitoring (Preprint) |
APR 2006 |
11 pages |
| Authors:
Steven E. Olson; Martin P. DeSimio; Mark M. Derriso; DAYTON UNIV OH RESEARCH INST
|
| Structural health monitoring techniques are being developed to reduce operations and support costs, increase availability, and maintain safety of current and future air vehicle systems. The use of Lamb waves, guided elastic waves in a plate, has shown promise in detecting localized damage, such as cracking or corrosion, due to the short wavelengths of the propagating waves. The use of such techniques for structural health monitoring of simple plate and ... |
|
| Non-Chromated Coating Systems for Corrosion Protection of Aircraft Aluminum Alloys (Preprint) |
APR 2006 |
14 pages |
| Authors:
N. Voevodin; D. Buhrmaster; V. Balbyshev; A. Khramov; J. Johnson; R. Mantz; DAYTON UNIV OH RESEARCH INST
|
| The Air Force requires the development of an environmentally compliant chromate-free aircraft coating system that meets or exceeds current corrosion protection capabilities. A number of non-chromated pretreatments and primers have been independently developed over the past years. This report compares the corrosion resistance performance of selected fully non-chromate systems to the standard chromate containing coating system. The data identified two non-chromated systems that performed comparably to the standard chromated aircraft ... |
|
| Propulsion and PWR Rapid Response Research and Development (R&R) Support: Delivery Order 0030: Study of Hot Deformation of Nanocomposite Rare Earth Magnets |
MAR 2006 |
53 pages |
| Authors:
Shiqiang S. Liu; DAYTON UNIV OH RESEARCH INST
|
| High performance bulk anisotropic nanograin composite Nd2Fe14B/Fe and Nd2Fe14B/Fe-Co magnets were successfully synthesized using hot compacting blended Nd-Fe-B and ?Fe-Co powders or coated ND-Fe-B powders followed by a subsequent hot deformation. Using both techniques, (BH)max could reach 45-55 MGOe. In addition, bulk anisotropic hybrid nanograin Pr2Fe14B/PrCo5 magnets with improved thermal stability were synthesized, and nanograin Sm2(Co, Fe) 17Fe-Co magnets were studied. |
|
| Analytical Modeling of Lamb Waves for Structural Health Monitoring (Preprint) |
MAR 2006 |
11 pages |
| Authors:
Steven E. Olson; Martin P. DeSimio; Mark M. Derriso; DAYTON UNIV OH RESEARCH INST
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| Structural health monitoring techniques are being developed to reduce cost, increase availability, and maintain safety of current and future air vehicle systems. Various techniques have been investigated depending on the scale of the damage to be detected. For example, damage such as fastener failure may have a more global effect on the structural dynamics and therefore modal-based damage detection techniques may be suitable. This paper focuses on detecting smaller scale ... |
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| Composites Containing Barrier Layers for Reduced Permeability at Cryogenic Temperatures |
MAR 2006 |
13 pages |
| Authors:
Vernon T. Bechel; Steven L. Donaldson; Ran Y. Kim; DAYTON UNIV OH RESEARCH INST
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| To help prevent leakage that may occur if cracks develop in a cryogenic composite pressure vessel due to thermo-mechanical fatigue, liners are occasionally implemented. However, liners can be difficult to fabricate and maintain, and mismatch of their CTE with the underlying composite can promote debonding of the liner. In this effort, two approaches to incorporating a barrier layer directly into a carbon/bismaleimide PMC (IM7/5250-4) were investigated for their effectiveness in ... |
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| User Feedback on RFID and Integrated Flightline Data for Maintenance Decisions |
JAN 2006 |
8 pages |
| Authors:
DAYTON UNIV OH RESEARCH INST
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| Implications of Conation for Design: Presentation/Briefing |
08 DEC 2005 |
12 pages |
| Authors:
DAYTON UNIV OH RESEARCH INST
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| Aerospace Power Scholarly Research Program. Delivery Order 0011: Single Ionic Conducting Polymer Electrolyte |
DEC 2005 |
19 pages |
| Authors:
Allen Turner; DAYTON UNIV OH RESEARCH INST
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| This report focuses on the development of a lithium-ion conducting channel as a solid-state electrolyte for rechargeable lithium batteries. Dilithium phthalocyanine (Li2Pc) has been used in this development since it can undergo molecular self-assembly to form the ionically conducting channel. The essential features of the channel are that it is designed such that the anion matrix of the unsaturated macrocycle forms the channel through which the lithium ions move, thus ... |
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| Power and Thermal Technologies for Air and Space. Delivery Order 0001: Single Ionic Conducting Solid-State Electrolyte |
NOV 2005 |
22 pages |
| Authors:
Allen Turner; DAYTON UNIV OH RESEARCH INST
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| This report focuses on the development of a lithium-ion conducting channel as a solid-state electrolyte for rechargeable lithium batteries through the use of thin films of dilithium phthalocyanine (Li2Pc) which have been solvent cast onto manganese dioxide cathodes. Experimental procedures have been developed which have resulted in the successful deposition of Li2Pc with low ionic resistance. AC impedance measurements and analysis of the equivalent circuit has shown that specific ionic ... |
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Reports by Corporate Author
