| Improvement of Piezoelectricity in Piezoelectric Paper Made With Cellulose |
25-Nov-2009 |
10 pages |
| Authors:
Jaehwan Kim; INHA UNIV INCHEON (SOUTH KOREA)
|
 | This report deals with the improvement of piezoelectricity in the piezoelectric paper made with cellulose. Piezoelectric paper fabrication process is composed of cellulose dissolving, wet cellulose casting, regenerating cellulose, stretching and drying processes. To automate these serial processes, a pilot plant was developed for the wet cellulose casting, regenerating, stretching and drying processes. |
|
| GigE Advanced Imaging Sensor |
23-Nov-2009 |
9 pages |
| Authors:
Lon van Sunshine; Peter Ham; BAE SYSTEMS NASHUA NH
|
| An advanced sensor was developed and tested under this effort. This sensor uses an EMCCD with an active focal plane of 658 by 496 pixels, in conjunction with a controllable iris and wide field of view lens to provide situation awareness over full daylight to extreme dark conditions. The interface to the sensor is over GigE, allowing high data rate signal transmission. Intensive mechanical design was applied to advance the ... |
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| Combat Vehicle Fire Control Systems - Drift |
09-Nov-2009 |
7 pages |
| Authors:
ABERDEEN TEST CENTER MD
|
| This TOP describes procedures for determining the deviation of the line of sight (LOS) of a sighting system (integrated), or gun/turret drive with respect to initial alignment with a target, without external inputs, as a function of time. Level and canted vehicle orientations are investigated to determine if any interaction exists between azimuth and elevation. The reader is referred to TOP 3-2-836 (0) Combat Vehicle Fire Control Systems - Overview ... |
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| Combat Vehicle Fire Control Systems - Coincidence |
09-Nov-2009 |
16 pages |
| Authors:
ABERDEEN TEST CENTER MD
|
| This document describes the procedures for determining the coincidence window of a tank fire control system. The coincidence window is defined as the limits around exact sight/gun alignment within which the gun is permitted to fire (omitting the offsets imposed by a ballistic solution). Typically, a combat vehicle implements the coincidence windows based on the current alignment (static) and in some cases additionally the future alignment (dynamic) of the sight ... |
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| Liquid Crystal Based Optical Phased Array for Steering Lasers |
Oct-2009 |
192 pages |
| Authors:
Lei Shi; Philip Bos; KENT STATE UNIV OH
|
| Beam steering technologies are attracting more and more research interests and attention because of the benefits of fast tuning, light weight, and synergy with adaptive optics. The liquid crystal OPA technology has been considered for small angle beam steering because of the small pitch, low driving voltages, large birefringence, flexibility, and electrical control. However, the large area resets of the phase profile caused by the fringe fields degrade the achievable ... |
|
| Foundation Elements for Naval Low-Rise Buildings |
Oct-2009 |
201 pages |
| Authors:
Mark Hatch; Michael P Wolcott; WASHINGTON STATE UNIV PULLMAN WOOD MATERIALS AND ENGINEERING LAB
|
| Natural fiber composites are commonly used in residential decking, siding, and fencing applications, but their use in high-load structural applications has been limited by their low strength performance. However, wood-plastic composites (WPCs) consisting of nylon 12 and thermoplastic epoxy resin (TPER) exhibit excellent mechanical performance. This study evaluated the extrusion parameters for each composite including: barrel/die temperature profile, lubricant compatibility, wood flour (WF) content, and WF moisture content (MC). Increases ... |
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| A Computational Analysis of a Shear Punch Test |
Aug-2009 |
14 pages |
| Authors:
Stephan R Bilyk; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The intense shearing that occurs in propellants and explosives during impulsive loading can lead to initiation. In an effort to determine useful shear initiation criteria, the U.S. Army Research Laboratory (ARL) has developed a shear punch test using a modified Kolsky bar. Varying the striker bar's velocity and length controls the shear rate and duration. Shear velocities approaching 100 m/s and durations as long as 200 microns are possible. Experimental ... |
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| Mechanical Response and Shear Initiation of Double-Base Propellants |
Aug-2009 |
16 pages |
| Authors:
Stephan R Bilyk; Michael J Scheidler; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The intense shearing that occurs in propellants during impulsive loading can lead to initiation. In an effort to determine useful shear initiation criteria, the U.S. Army Research Laboratory has developed a dynamic shear punch test using a modified split- Hopkinson bar. Varying the striker bar's velocity and length controls the shear rate and duration. Shear velocities approaching 100 m/s and durations as long as 0.2 ms are possible. Experimental results ... |
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| Transition in Gas Turbine Engine Control System Architecture: Modular, Distributed, Embedded |
Aug-2009 |
79 pages |
| Authors:
Al Behbahani; Dennis Culley; Bill Mailander; Dewey Benson; Bruce Wood; Derek Weber; Bill Rhoden; Gary Hunter; Casey Carter; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| Presentations from the Distributed Engine Control Working Group included: Vision and need for future turbine engine control; Implementation and technology challenges; High temperature electronics; Innovation and entry barriers. |
|
| Analysis of Commercial Unsaturated Polyester Repair Resins |
Jul-2009 |
50 pages |
| Authors:
Xing Geng; Vincent Crisostomo; James M La Sands; Casey Greer; Kevin Andrews; Ian McAninch; Giuseppe R Palmese; John J Scala; Scott Bingham; Steven Suib; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The basic rheological, thermal, and mechanical properties of commercially available repair putties have been determined in this study, as has the composition of these products. These products contain 33% to 40% unsaturated polyester resin, 10% to 20% styrene, and 45% to 57% inorganic fillers. The fillers are made up of hollow glass microspheres, talc, magnesium carbonate, calcium carbonate, fumed silica, glass fibers, and various other minerals. These products have a ... |
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| Laboratory Characterization of Cor-Tuf Concrete With and Without Steel Fibers |
Jul-2009 |
83 pages |
| Authors:
Erin M Williams; Paul A Reed; Steven S Graham; Todd S Rushing; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS GEOTECHNICAL AND STRUCTURES LAB
|
| Personnel of the Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, conducted a series of laboratory experiments to investigate the strength and constitutive property behavior of baseline ultra-high-performance composite (Cor-Tuf) concrete with and without steel fibers. A total of 23 mechanical property tests were successfully completed for Cor-Tuf1 and Cor-Tuf2 concrete. The mechanical property tests included hydrostatic compression, unconfined compression (UC), triaxial compression (TXC), unconfined direct pull ... |
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| Effects of Prior Aging at 288 deg C in Argon Environment on Creep Response of Carbon Fiber Reinforced PMR-15 Composite with + or - 45 deg Fiber Orientation at 288 deg C |
Jun-2009 |
106 pages |
| Authors:
Tyler F Gruters; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| The creep and recovery response of carbon fiber reinforced PMR-15 composite with a + or - 45 fiber orientation was examined in an argon environment at 288 deg C. Mechanical testing was executed for unaged specimens as well as specimens aged up to 1000 hours. Tensile tests were performed to determine Young's modulus of elasticity and ultimate tensile strength. The creep tests were carried out at stress levels of 30 ... |
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| Initial Evaluation of Advanced Powder Metallurgy Magnesium Alloys for Armor Development |
May-2009 |
46 pages |
| Authors:
Tyrone Jones; Katsuyoshi Kondoh; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The U.S. Army Research Laboratory (ARL) is interested in assessing the performance of different magnesium alloys. ARL and the Joining and Welding Research Institute (JWRI) conducted an effort to develop and evaluate advanced powder metallurgy magnesium alloys AZ31B and AMX602 (Mg-6Al-0.5Mn-2Ca/mass%) sheets. JWRI performed the mechanical and metallurgical analysis, while ARL performed the ballistic analysis. The thin-gauge magnesium alloy sheets were ballistically evaluated against the 0.22-cal. fragment-simulating projectile. The magnesium ... |
|
| Frequency Stabilization of a Single Mode Terahertz Quantum Cascade Laser to the Kilohertz Level |
27-Apr-2009 |
9 pages |
| Authors:
Jerry Waldman; William D Goodhue; Thomas M Goyette; Andrew J Gatesman; Robert H Giles; William E Nixon; Andriy A Danylov; Michael J Coulombe; Xifeng Qian; MASSACHUSETTS UNIV LOWELL DEPT OF PHYSICS AND APPLIED PHYSICS
|
| A simple analog locking circuit was shown to stabilize the beat signal between a 2.408 THz quantum cascade laser and a CH2DOH THz CO2 optically pumped molecular laser to 3-4 kHz (FWHM). This is approximately a tenth of the observed long-term (t sec) linewidth of the optically pumped laser showing that the feedback loop corrects for much of the mechanical and acoustic-induced frequency jitter of the gas laser. The achieved ... |
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| A Combined Experimental and Computational Study to Examine Lateral Constraint Effects on Single-Slip Oriented Microcompression Experiments (Preprint) |
Apr-2009 |
18 pages |
| Authors:
H L Fraser; M D Uchic; D M Dimiduk; P A Shade; R Wheeler; Y S Choi; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| A custom in-situ SEM mechanical testing system has been used to study the compressive deformation behavior of single-slip oriented Rene N5 microcrystals. Two different compression platens were used to explore the effect of lateral stiffness on the resultant mechanical response, which approximated either a full-frictional or zero-friction case. The change in the lateral constraint of the test system had a demonstrable effect on many aspects or attributes of plastic flow: ... |
|
| Novel MEMS Apparatus for In Situ Thermo-Mechanical Tensile Testing of Materials at the Micro- and Nano-Scale (Preprint) |
Apr-2009 |
6 pages |
| Authors:
M D Uchic; J Han; T Saif; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| We present, for the first time, a MEMS-based test methodology that potentially enables elevated-temperature mechanical tensile testing of nano- and micro-scale samples within a SEM or TEM (T 500 degrees C). Importantly, the test methodology allows for the samples to be fabricated separately from the MEMS-apparatus, a significant advancement from other test devices developed by some of the present authors. Therefore the test methodology should be applicable to the study ... |
|
| Anisotropy of the Hot Plastic Deformation of Ti-6Al-4V Single-Colony Samples (Preprint) |
Apr-2009 |
26 pages |
| Authors:
S L Semiatin; A A Salem; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| The critical resolved shear stresses and flow curves for the seven possible slip systems in Ti-6Al-4V with a lamellar microstructure were determined via high temperature uniaxial compression testing. For this purpose, samples with a rectangular cross section were cut from single colonies grown using a float-zone technique and then tested at 815 degrees C. Each sample was oriented for single slip along one of seven different slip systems in the ... |
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| NRL/NAVSEA Research and Related |
30-Mar-2009 |
39 pages |
| Authors:
Shelby F Thames; James W Rawlins; Lon Mathias; Kenneth Mauritz; Sergei Nazarenko; Robson F Storey; Marek Urban; UNIVERSITY OF SOUTHERN MISSISSIPPI HATTIESBURG
|
| Waterborne, very low volatile organic compound (VOC) content Navy haze gray (NHG) coatings were developed using vegetable oil macromonomer (VOMM)-based latexes. The coatings successfully met the requirements of specifications MIL-PRF-24635C and MIL-PRF-24569A. The monomer and latex syntheses were scaled up to prepare 20 gallons of the NHG coating, which was shipped to two Florida locations, Pentech and NRL, for evaluation on December 2, 2008. AFM characterization techniques developed to track ... |
|
| Development of a Fuel Lubricity Haze Test (FLHT) for Naval Applications |
16-Mar-2009 |
78 pages |
| Authors:
Dennis R Hardy; NAVY TECHNOLOGY CENTER FOR SAFETY AND SURVIVABILITY WASHINGTON DC
|
| Highly processed diesel fuels are now monitored for lubricity by specially developed mechanical tests. Because these mechanical tests are imprecise, difficult to run, expensive, and difficult to relate to actual field conditions, a chemical test for lubricity has been developed. This Fuel Lubricity Haze Test (FLHT) has been miniaturized, and can be run in the laboratory or field. It has been found to be an objective, precise test that is ... |
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| Environmental Effects on Fatigue Crack Growth in High Performance Aluminum Alloys |
13-Mar-2009 |
6 pages |
| Authors:
J J Williams; N Chawla; ARIZONA STATE UNIV TEMPE
|
| Aluminum alloys are used in a variety of structural applications, such as aircraft wings, fuselage, etc. In addition to cyclic mechanical loads, these alloys are often subjected to aggressive corrosive environments, e.g., salt water and moisture. Thus, a comprehensive understanding of the combined effects of cyclic mechanical loading and environmental effects is necessary. |
|
| Molecular Design of Novel Poly(urethane-urea) Hybrids as Helmet Pads for Ballistic and Blast Trauma Mitigation |
Mar-2009 |
22 pages |
| Authors:
Alex J Hsieh; Joshua A Orlicki; Rick L Beyer; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Polyurethane (PU) and poly(urethane urea) (PUU) based foams are currently being used as helmet pad materials. The U.S. Army still has a critical need for more efficient foam pad materials and designs that will provide warfighters with improved survivability against blast-induced traumatic brain injuries. Recent work has shown that tailoring the microphase-separated morphology is critical in controlling the high strain-rate mechanical deformation of bulk PU and PUU elastomers. In this ... |
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| Development of Methods for the Quantification of Microstructural Features in Alpha+Beta Processed Alpha/Beta Titanium Alloys (Preprint) |
Mar-2009 |
22 pages |
| Authors:
J Tiley; H L Fraser; P C Collins; B Welk; T Searles; J C Russ; NORTH TEXAS STATE UNIV DENTON
|
| A set of stereological procedures has been developed for the rigorous quantification of microstructural features resolvable using scanning electron microscopy in alpha+beta processed alpha/beta titanium alloys. This paper identifies the four microstructural features that most likely influence the mechanical properties in alpha+beta processed titanium alloy, including: the size of the equiaxed alpha, the volume fraction of the equiaxed alpha, the volume fraction of total alpha, and the thickness of the ... |
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| Aircraft Steels |
19-Feb-2009 |
46 pages |
| Authors:
R Taylor; E U Lee; C Lei; H C Sander; NAVAL AIR WARFARE CENTER AIRCRAFT DIV PATUXENT RIVER MD
|
| Five high strength steels (4340, 300M, AerMet 100, Ferrium S53, and Hy-Tuf) and four stainless steels (High Nitrogen, 13-8Mo, Custom 465, and MLX17) have been evaluated with respect to their characteristics and applicability to the current and future Navy aircraft. In this endeavor, their metallurgical feature, mechanical property, fatigue behavior, and corrosion resistance have been investigated and compared. |
|
| Nanostructured Self-Healing Surface Films |
05-Feb-2009 |
20 pages |
| Authors:
Hong Liang; TEXAS A AND M UNIV CORPUS CHRISTI TX
|
| SUMMARY: Mechano-chemical process to form a surface film * Mechanical energy is highly controllable * The film can lubricate, self-repair, maintain, and extend materials service life significantly. |
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| Fabrication of Nanolaminates with Ultrathin Nanolayers Using Atomic Layer Deposition: Nucleation & Growth Issues |
Feb-2009 |
36 pages |
| Authors:
Steven M George; COLORADO UNIV AT BOULDER DEPT OF CHEMISTRY AND BIOCHEMISTRY
|
| This AFOSR grant concentrated on the fabrication of nanolaminates with ultrathin nanolayers using atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques. Nanolaminates are multilayered thin film structures with nanometer dimensions and very high interfacial density. These multilayer structures can display novel properties that can be optimized by manipulating the thickness and composition of the individual nanolayers. During this grant, the research examined nucleation and growth issues involved in ... |
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| Hot-Pressed Versus Sintered LiTi2(PO4)3 |
Feb-2009 |
28 pages |
| Authors:
Jeff Wolfenstine; Jan L Allen; James Sumner; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
|
| The electrical and mechanical properties of hot-pressed versus sintered LiTi2(PO4)3 were investigated. The hot-pressed LiTi2(PO4)3 had a higher density and larger average grain size than the sintered material. As a result of these microstructural differences, the hot-pressed material exhibited a higher total ionic conductivity and lower hardness. The electronic conductivity of both materials was the same, and increased by a factor of about 107 when the hot-pressed and sintered materials ... |
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| Microstructural and Mechanical Behavior Characterization of Ultrasonically Consolidated Titanium-Aluminum Laminates |
Feb-2009 |
12 pages |
| Authors:
DATTATRAYA DANDEKAR; Tomoko Sano; James Catalano; Daniel Casem; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Multilayered hybrid metal laminates have been studied for structural applications due to their potential for higher strength, toughness, and stiffness. The goal of this study was to modify the microstructure and mechanical properties of commercial purity titanium (CP-Ti) and 1100 aluminum (Al) laminates for potential applications in mine blast mitigation. Alternating layers of 50 micron thick CP-Ti and Al layers were ultrasonically consolidated. To provide high hardness and stiffness, the ... |
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| Magnesium Technology and Manufacturing for Ultra Lightweight Armored Ground Vehicles |
Feb-2009 |
14 pages |
| Authors:
Kyu Cho; Paul Moy; Tomoko Sano; Kevin Doherty; Chian Yen; George Gazonas; Jonathan Montgomery; Bruce Davis; Rick DeLorme; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The current paper summarizes magnesium alloy metallurgy and wrought manufacturing with an initial emphasis on the Elektron WE43 alloy system for lightweight armored ground vehicle applications. Engineering design factors are reviewed and initial mechanical property data are presented along with ballistic results and findings from blast simulations. Finally the future role of magnesium alloys in ultra light metallic armor is discussed in terms of material development and application. |
|
| The Effect of Moisture Transport on Corrosion Protective Coatings, or, Being Careful with Accelerated Weathering |
Feb-2009 |
13 pages |
| Authors:
Xiaodong Shi; Brian R Hinderliter; Stuart G Croll; NORTH DAKOTA STATE UNIV FARGO
|
| OUTLINE: Not about corrosion directly -- But about the protective coatings -- How they up take water -- How long they take to respond. Introduction and Motivation -- Approaches -- Modeling -- Experiment -- Conclusions -- Acknowledgment. IMPORTANCE OF COATINGS: Principal protection against corrosion -- The end is in sight when the coating is defeated. |
|
| Thin Films of Polypyrrole on Particulate Aluminum |
Feb-2009 |
22 pages |
| Authors:
Victoria J Gelling; Christopher Vetter; Xiaoning Kasi Qi; Subramanyam V Somayajula; NORTH DAKOTA STATE UNIV FARGO
|
| WHY CONDUCTING POLYMERS? Perhaps act as Smart Coating * Release of Corrosion Inhibiting Anions * Mixed Potential between surface and ECP * Perhaps acts as an oxidant to form passive layer. WHY POLYPYRROLE/FLAKE? Polypyrrole * Poor mechanical properties * Poor adhesion * Solubility issues * Continuous layer needed. Polypyrrole Coated Flake * Easy coating incorporation * Less quantity of conducting polymer required * Solubility is not an issues. |
|
| The Analysis and Modeling of Phase Stability and Multiphase Designs in High Temperature Refractory Metal-Silicon-Boron Alloys |
27-Jan-2009 |
46 pages |
| Authors:
John H Perepezko; WISCONSIN UNIV-MADISON BOARD OF REGENTS/RESEARCH SPONSORED PROGRAMS
|
| For high temperature application beyond the range of Ni-base superalloys, Mo-Si-B alloys with the ternary intermetallic, Mo5SiB2, T2, phase as a key microstructure constituent, offer an attractive property balance of high melting temperature, oxidation resistance and useful high temperature mechanical properties. The fundamental basis of the alloying behavior in T2 including the mutual solid solution with transition metals has been established in terms of the governing geometric and electronic factors. ... |
|
| Simulator Test and Evaluation |
13-Jan-2009 |
19 pages |
| Authors:
ARMY AVIATION TECHNICAL TEST CENTER FORT RUCKER AL
|
| This TOP provides procedures for evaluating a simulator. It is geared towards a helicopter simulator but could also be used for a fixed-wing aircraft simulator. Simulators are designed with a limited mission. Full understanding of that mission is required so that an appropriate evaluation can be made. Failure to evaluate to the specific mission will result in shortcomings and deficiencies being identified that are outside of the intent of the ... |
|
| The Mechanosensitive Ca2+ Channel as a Central Regular of Prostate Tumor Cell Migration and Invasiveness |
Jan-2009 |
126 pages |
| Authors:
Owen P Hamill; Rosario Maroto; TEXAS UNIV MEDICAL BRANCH AT GALVESTON
|
| Our patch clamp studies indicate MscCa is expressed by the invasive prostate tumor cell PC-3. Anti-MscCa agents, Gd3+, GsmTx-4, and an anti-TRPC1 antibody block PC-3 cell migration. MscCa activity can be recorded over the surface of the PC-3 cell but is expressed at higher density on the rear compared with the front of the cell. This channel density gradient combined with a higher density of thapsigargin-sensitive Ca2+ stores in the ... |
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| Intermolecular Slip Mechanism in Tropocollagen Nanofibrils |
Jan-2009 |
8 pages |
| Authors:
Markus J Buehler; Alfonso Gautieri; Simone Vesentini; Alberto Redaelli; MASSACHUSETTS INST OF TECH CAMBRIDGE OFFICE OF SPONSORED RESEARCH
|
| Collagen is the most important structural protein in the animal kingdom and is responsible for the strength and integrity of many tissues like bone, teeth, cartilage and tendons. The mechanical properties of these tissues are determined by their hierarchical structure. However, how each level contributes to the overall properties of collagenous tissues, and how individual hierarchical levels interact, remains poorly understood. Furthermore, despite extensive experimental and computational studies including both ... |
|
| Evaluation of Rigid-Rod Polymeric Fibers by Post-Treatment in scC02 |
30-Dec-2008 |
37 pages |
| Authors:
Alan J Lesser; MASSACHUSETTS UNIV AMHERST DEPT OF POLYMER SCIENCE AND ENGINEERING
|
| Poly-p-phenelenebenzobisoxazole (PBO, commercial name ZylonTM, Toyobo Co.)is one of the rigid-rod polymers which produces fiber with excellent mechanical properties. This polymer, originally developed by the U.S. Air Force to replace metals in space and aviation applications, is currently one of the more promising materials for fibers used in personnel ballistic armors. In this study we evaluate the degradation mechanisms of PBO fibers and investigate strategies to stabilize them using supercritical ... |
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| Generating High Modulus Fibers by Nanoparticle Incorporation with Potential to Introduce Multifunctionality |
07-Dec-2008 |
15 pages |
| Authors:
Michael E Mackay; Phillip M Duxbury; MICHIGAN STATE UNIV EAST LANSING CONTRACT AND GRANT ADMINISTRATION
|
| The aim of this project is to develop the technology of stabilizing and controlling nanoparticle dispersion in polymers and in particular to apply this technology to the production of high modulus fibers which can be designed to have a variety of multifunctional capabilities. We have found that prestraining a glassy polymer (polystyrene) containing a very small amount (1 wt%) of well dispersed nanoparticles produces a material that has a larger ... |
|
| Responsive Polymer Interfaces |
02-Dec-2008 |
11 pages |
| Authors:
Alfred J Crosby; MASSACHUSETTS UNIV AMHERST MA OFFICE OF GRANT AND CONTRACT ADMIN
|
| This project focused on the fabrication and characterization of responsive polymer interfaces to be used as smart coatings that dynamically alter surface properties, advanced optical devices, and/or sensors. Transition speed, magnitude of change, and sensitivity are primary challenges in the development of responsive surfaces. To meet these challenges, we developed polymer surfaces with controlled shell structures that transition via snap-through or crumpling elastic instabilities upon the application of a trigger. ... |
|
| Development Of Frequency Transfer Via Optical Fiber Link at NICT |
01-Dec-2008 |
11 pages |
| Authors:
Mizuhiko Hosokawa; Motohiro Kumagai; Mihu Fujieda; Tadahiro Gotoh; NATIONAL INST OF INFORMATION AND COMMUNICATIONS TECHNOLOGY (NICT) TOKYO (JAPAN)
|
| NICT in Japan has developed a radio frequency (RF) dissemination system using an optical fiber link. The phase noise induced during the transmission through the optical fiber is actively cancelled by a compensation system. A proving test has been conducted on the 114-km urban telecom optical fiber link in Tokyo. The transfer stability in the 10-18 level at an averaging time of 1 day was achieved. In the last few ... |
|
| Stabilization System for Camera Control on an Unmanned Surface Vehicle |
Dec-2008 |
51 pages |
| Authors:
Jaya K Kandasamy; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| SeaFox is an unmanned surface vehicle (USV) primarily used for maritime security operations. Currently, a remotely operated vision based camera is used to track a particular target whilst the USV approaches the intended target. While the USV is in motion, the hydrodynamic forces and mechanical vibrations makes it difficult for the operator to lock on to the target at all times. This thesis addresses this issue through the development of ... |
|
| Development of a Ballistic Specification for Magnesium Alloy AZ31B |
Dec-2008 |
52 pages |
| Authors:
Tyrone L Jones; Richard D DeLorme; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The U.S. Army Research Laboratory (ARL) and Magnesium Elektron North America (MENA) have conducted a joint effort to develop and evaluate rolled plate in commercially available magnesium alloy-temper AZ31B-H24. MENA produced the rolled product and conducted the mechanical analysis, while ARL performed the ballistic analysis. The magnesium alloy plates were parametrically compared with the minimum performance requirements of aluminum alloy 5083-H131 temper rolled plate using various armor-piercing and fragment-simulating projectiles ... |
|
| Friction on Crack Surfaces During Compression of Explosives - A Possible Ignition Source for Unplanned Explosions Due to Accidental Deformations |
Dec-2008 |
8 pages |
| Authors:
Donald A Wiegand; Brett Redingius; Kevin Ellis; Claire Leppard; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
|
| The mechanical properties of composite plastic bonded explosives have been investigated as a function of confining pressure. The results indicate different failure processes in two pressure ranges, a low pressure range between about 0.1 to 7.0 MPa which is considered in this paper and a higher pressure range. In the low pressure range crack processes are important in failure. The pressure dependence of the compressive strength in the low pressure ... |
|
| Nondestructive Evaluation (NDE) of Sintered Silicon Carbide and its Correlation to Microstructure and Mechanical Properties |
Dec-2008 |
9 pages |
| Authors:
Steven Miller; Ernest Chin; William Green; James Campbell; Douglas M Slusark; M V Demirbas; Andrew Portune; Richard A Haber; Raymond Brennan; RUTGERS - THE STATE UNIV PISCATAWAY NJ
|
| High density is a critical acceptance criterion for armor ceramics. Quantifying the difference in density between what would be considered to be a good or bad region is complicated. As density is reduced from theoretical, does this infer the presence of defects? The minimum acceptable density that ensures favorable ballistic performance is unknown. This question concerns not only the presence of defective regions, which may include pores or inclusions, but ... |
|
| Development of a Tissue Engineered Scaffold for Meniscus Replacement |
Dec-2008 |
8 pages |
| Authors:
E A Balint; Gatt; C J Jr; M G Dunn; ROBERT WOOD JOHNSON UNIV HOSPITAL NEW BRUNSWICK NJ
|
| It is well accepted that the loss of meniscal function due to surgical removal is a significant factor in the onset of degenerative osteoarthritis of the knee. Few viable alternatives exist for the replacement of significantly damaged tissue. In this study, two potential designs for meniscus scaffolds were compared with a focus on the mechanical protection they provide the articular surfaces and their overall biological incorporation into synovial tissue. Three ... |
|
| Simulations of Simple Nanomachines in Carbon Nanotude Bundles Based on Chirality |
Dec-2008 |
8 pages |
| Authors:
D L Majure; R W Haskins; N J Lee; C R Welch; C F Cornwell; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
|
| Single-walled carbon nanotubes (CNTs) have been studied extensively since their discovery and identification by Iijima in 1993. Their impressive mechanical, electrical, and thermal properties have created new fields of study, and the benefits of this research are just beginning to be realized. One potential use of CNTs is as a foundation for nanomachines. Another possible use, one that takes advantage of their mechanical properties, is the synthesis of high-strength, low-weight ... |
|
| Simulation and Design of Nanocomposite for Application in Ballistic Protection |
Dec-2008 |
10 pages |
| Authors:
Zheng-Dong Ma; Dongying Jiang; Yuanyuan Liu; Basavaraju Raju; Yushun Cui; ARMY TANK-AUTOMOTIVE AND ARMAMENTS COMMAND WARREN MI
|
| The objective of this research is to develop a modeling, simulation, and design tool for nanocomposites in order to predict, with accepted fidelity, nano-composite behaviors; and to design optimum nanocomposites for specific Army applications such as ballistic protection. Based on a unit cell model created for nanoclay-epoxy composites, the effect of nanoparticle distribution on the maximum stress developed in epoxy resin was investigated using the Meshfree Particle Method based simulation ... |
|
| Using Plasticity Values Determined from Systematic Hardness Indentation Measurements for Predicting Impact Behavior in Structural Ceramics: A New, Simple Screening Technique |
Dec-2008 |
7 pages |
| Authors:
James W McCauley; Trevor E Wilantewicz; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| In general, it has long been known that the hardness of ceramics correlates with gross impact performance, however, not to a degree useful for materials development. Wilkins, Cline and Honodel, 1969, were the first to point out the apparent importance of ceramic plasticity or inelastic deformation mechanisms in BeO and AlN in impact performance. More recently, Lundberg et al., 2000, have made compelling arguments that the compressive yield strength (related ... |
|
| Computational Design of Biomimetic Gels With Properties of Human Tissues |
Dec-2008 |
9 pages |
| Authors:
J Andzelm; Y Sliozberg; J K Brennan; M VanLandingham; V Pryamitsyn; V Ganesan; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| The effective design of body armor requires the use of biomimicking materials that accurately and robustly reproduce the characteristic mechanical behavior of human tissues. The mechanical performance of the soft tissues is determined by their viscoelastic properties and for this reason the optimal soft tissue surrogate must viscoelastically mimic the original tissue. One traditional tissue surrogate material is a water-based gelatin gel that has poor environmental stability and limited tailorability. ... |
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| Piezomems Devices for Advanced Communications and Phased Array Radar |
Dec-2008 |
5 pages |
| Authors:
Daniel Judy; Ronald G Polcawich; Jeffrey S Pulskamp; ARMY RESEARCH LAB ADELPHI MD SCIENCES AND ELECTRON DEVICES DIRECTORATE
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| In this article, we report on the successful demonstration of lead zirconate titanate (PZT) thin film based MEMS devices for use in radio frequency (RF) systems. Individual series switches and single pole multi-throw switching elements operating at or below 10 V have been developed capable of operating over a wide temperature range. The switch technology also provides an enabling technology for low voltage, mechanical logic. Along with switches and phase ... |
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| Bridging the Gap in Military Robotics (Combler le Fosse Existant dans le Domaine de la Robotique Militaire) |
Nov-2008 |
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| Authors:
NATO RESEARCH AND TECHNOLOGY ORGANIZATION NEUILLY-SUR-SEINE (FRANCE)
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 | There appears to exist a gap between the ideas of the military on the use of ground robotics for their purposes and the technical possibilities offered by industry and research. In many cases the military are offered robots created by industry, but to a lesser degree robots developed to explicitly meet military needs. To bridge this gap, a NATO workshop was organised September 2004 in Bonn, attended by over 70 ... |
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| Microstructure and Properties of WC Spheres |
Nov-2008 |
32 pages |
| Authors:
Jeffrey J Swab; Justin Pritchett; Andrew A Wereszczak; Osama M Jadaan; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| Tungsten carbide (WC) spheres are used as projectiles to study the ballistic performance of armor materials and systems. In order to properly understand and model the interaction between the projectile and the armor, it is necessary to have properties of both. In this study, the physical and mechanical properties of two commercially available WC spheres (nominally 0.25 inch in diameter) used in some ballistic impact studies were determined. One WC ... |
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Reports by Keyword(s)
MECHANICAL PROPERTIES
