The effects of hot isostatic pressing on the physical and electrical properties of sintered lead zirconate titanate are presented. Hot isostatic pressing for short times (1 hour) with low applied pressures (6.9 - 20.7 MPa) at 1300 deg C is shown to produce lead zirconate titanate with a higher density than that obtained by conventional sintering techniques. Densification is shown to occur without an appreciable change in grain size. Localized microstructural inhomogenieties observed after...
Topics: DTIC Archive, Ewsuk,Kevin G, PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB, *CERAMIC...
Ferroelectric oxides deform appreciably under electric field. They are used now as large strain ceramic actuators where a moderate electric voltage can deliver an appreciable mechanical motion. The electrostrictive and piezoelectric strains are incompatible around inhomogeneities, such as electro edge and inclusions. Cracking under electric loading has been identified in recent years. This program seeks to quantify various cracking mechanisms so that future actuator design will have scientific...
Topics: DTIC Archive, Suo, Zhigang, CALIFORNIA UNIV SANTA BARBARA DEPT OF MECHANICAL ENGINEERING,...
Smart materials such as SMA and piezoelectric materials offer promising applications in many adaptive structures enabling the development of new structural control. Potential applications include shape control of large space structures, active noise and vibration control, flutter suppression, and microservoelasticity in flight vehicles. To deliver the maximum actuation power, piezoelectric actuators are subjected to high electric fields and strains. The development of reliability and life...
Topics: DTIC Archive, Sun, C. T., PURDUE UNIV LAFAYETTE IN SCHOOL OF AERONAUTICS AND ASTRONAUTICS,...
Chemical solution processing of Gd2Zr2O7 (GZO) thin films via sol-gel and metalorganic decomposition (MOD) precursor routes have been studied on textured Ni-based tape substrates. Even though films processed by both techniques showed similar property characteristics, the MOD-derived samples developed a high degree of texture alignment at significantly lower temperatures. Both precursor chemistries resulted in exceptionally dense, pore-free, and smooth microstructures, reflected in the...
Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIR/POWER DIV/MECHANICAL...
An ad hoc subcommittee on piezoceramics, under the sponsorship of the American Defense Preparedness Association (ADPA), has revised DOD-STD-1376A(SH). The revision represents the collective thoughts of Government agencies, laboratories, industrial manufacturers, and universities who critiqued the existing standard and suggested areas for clarification and improvement. Major changes to the standard include the addition of two more materials, essentially non-overlapping ceramic parameters,...
Topics: DTIC Archive, Tims, Allan C., NAVAL RESEARCH LAB WASHINGTON DC, *CERAMIC MATERIALS, *PIEZOELECTRIC...
Composite piezoelectrics made from Calcium modified lead titanate rods embedded in a polymer matrix have been evaluated for hydrophone applications. These composites behave quite differently form the conventional 1- 3 composites made with lead zirconate titanate ceramics. Specifically, in the modified lead titanate case the magnitude of the d31 coefficient is enhanced in the composite structure, and consequently the hydrostatic dh coefficient is suppressed. Nevertheless, these composites...
Topics: DTIC Archive, Shaulov, Avner A, NAVAL RESEARCH LAB ORLANDO FL UNDERWATER SOUND REFERENCE...
A systematic investigation into some possible transformation tougheners alternative to zirconia (ZrO2) has been conducted. Three systems have been focussed upon: dicalcium silicate (Ca2S104), dysprosia (DY203) and nickel sulfide (NiS). Composites of Ca2SiO4 in calcium zirconate (CaZrO3) or magnesia (MgO) or fine grained, single phase pure, and Ba-doped Ca2S 04 were fabricated, microstructurally characterized and mechanically evaluated. Although surface grinding was able to stress-induce the...
Topics: DTIC Archive, Kriven, Waltraud M, ILLINOIS UNIV AT URBANA DEPT OF MATERIALS SCIENCE AND...
In this project, we proposed novel transformers for power supplies. Transformers consists of cascade of sections of transmission lines, each a quarter-wave length long at the design frequency. Power conversion is through the propagation of electromagnetic waves instead of magnetic flux. Parallel strip lines sandwiching a printed circuit board were used as the transmission lines. Printed meandered striplines on a multi-layer structure were used to optimize the component size. Three printed...
Topics: DTIC Archive, Yang, Hung D., ILLINOIS UNIV AT CHICAGO CIRCLE DEPT OF ELECTRICAL ENGINEERING AND...
Research on solution-derived ferroelectric thin-films and melt-derived ferroelectric glass-ceramics was conducted in parallel with considerable overlap in the compositions studied and the evaluations of the crystallization behavior, microstructural development, and resulting properties. Lead germane based ferroelectric thin films were developed with a room temperature pyroelectric coefficient over 90% of the single crystal value, and a pyroelectric figure of merit exceeding the highest reported...
Topics: DTIC Archive, Haun, Michael J., COLORADO SCHOOL OF MINES GOLDEN DEPT OF METALLURGICAL ENGINEERING,...
This report documents work carried out in the Materials Research Laboratory of the Pennsylvania State University over the first year of a new ONR sponsored University Research Initiative (URI) entitled Materials for Adaptive Structural Acoustic Control. For this report the activities have been grouped under the following topic headings: (1) General Summary Papers; (2) Materials Studies; (3) Composite Sensors; (4) Actuator Studies; (5) Integration Issues; (6) Processing Studies; (7) Thin Film...
Topics: DTIC Archive, Cross, L E, PENNSYLVANIA STATE UNIV UNIVERSITY PARK MATERIALS RESEARCH LAB, *ADAPTIVE...
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The goal of this investigation was to use the improved positions of the Einstein Slew Survey to help identify sources in background fields and; the North Ecliptic Pole region of Ginga data. Our main progress has been on the former of these two goals. In July, 1996, we performed a detailed search of the background regions at Leicester, UK. Only one of the Slew/Ginga fields had a high enough count rate (greater than 3 LAC cts s(exp -1)) for an unambiguous detection, given the known fluctuations...
Topics: ZIRCONATES, AMPOULES, CRYSTALLIZATION, ZIRCONIUM COMPOUNDS, METAL FLUORIDES, OPTICAL FIBERS,...
The effort consisted of experimental work to deposit and characterize thin films as well as a modeling effort. PZLT materials were emphasized, with several compositions examined. In addition, limited effort was directed toward deposition of other materials, including barium titanate and strontium barium niobate. (MM)
Topics: DTIC Archive, McNeil, J. R., NEW MEXICO UNIV ALBUQUERQUE DEPT OF ELECTRICAL ENGINEERING,...
The eighth International Symposium on the Applications of Ferroelectrics was held in) Greenville, SC, on August 30 to Sept 2, 1992. It was attended by approximately 260 scientists and engineers who presented nearly 200 oral and poster papers. The three plenary presentations covered ferroelectric materials which are currently moving into commercial exploitation or have strong potential to do so. These were (1) pyroelectric imaging, (2) ferroelectric materials integrated with silicon for use as...
Topics: DTIC Archive, Liu, M, CLEMSON UNIV SC, *THIN FILMS, *SILICON, *FERROELECTRIC MATERIALS,...
This effort compared five flight simulator visual display configurations using a simulated aerial refueling task. The configurations were (a) a helmet-mounted stereoscopic display with a 40 deg field of view (FOV), (b) a helmet-mounted biocular display with a 40 deg FOV, (c) the full Advanced Simulator for Pilot Training (ASPT) 300 FOV, (d) the ASPT visual display masked to present a 40 deg FOV, and (e) lead lanthanum zirconate titanate (PLZT) googles (stereoscopic) using one ASPT window....
Topics: DTIC Archive, Woodruff, Robert R, AIR FORCE HUMAN RESOURCES LAB BROOKS AFB TX, *FLIGHT SIMULATORS,...
In order to optimize the detection of acoustical signals in a hydrostatic mode for future applications, new transduction materials which combine active ferroelectric materials with other inert phase such as polymers were developed. These new composite piezoelectric materials exhibit hydrostatic piezoelectric coefficients that far exceed what the conventional lead-zirconate- titanate (PZT) ceramics can offer. The particular concept of 0-3 composites is discussed in detail as a typical example of...
Topics: DTIC Archive, Ting, Robert Y, NAVAL RESEARCH LAB ORLANDO FL UNDERWATER SOUND REFERENCE DETACHMENT,...
General expressions for Poisson's ratio are derived for hexagonal crystals; simplified forms are given for cases involving symmetry directions. Crystals of hexagonal symmetry include a number of the binary semiconductor systems with the piezoelectric wurtzite structure, such as GaN and AlN. These are becoming increasingly important for high technology applications. One of the most important representatives of this class is the family of poled electroceramics, including BaTiO3, PZT, and related...
Topics: DTIC Archive, Ballato, Arthur, ARMY RESEARCH LAB FORT MONMOUTH NJ, *CRYSTALS, *POISSON RATIO,...
The report reviews the present knowledge of the aging process in barium titanate and lead zirconate-titanate ferroelectric ceramics. By 'aging' is meant the passive change in the mechanical and electrical properties of a ferroelectric with time. Experimental data show that these constants vary linearly with the logarithm of time. The Smith, Street and Woolley, and Plessner theories for this logarithmic dependence are revised to remove some of the obscurity in the usual derivation. The...
Topics: DTIC Archive, DeLaunay, Jules, NAVAL RESEARCH LAB WASHINGTON DC, *FERROELECTRIC CRYSTALS,...
This is the last of a series of reports describing an experimental study of the critical factors and mechanisms involved in achieving high- emission-density cathodes capable of long life and reliable operation in electron tubes. Detailed results of the work of the last reporting period of this investigation are included herein, along with a review of the more significant developments of the entire two-year program. All of the objectives of the program have essentially been met, and in some...
Topics: DTIC Archive, Bondley, R J, GENERAL ELECTRIC CO SCHENECTADY NY, *CATHODES(ELECTRON TUBES), BARIUM...
Subcritical crack propagation in the transducer ceramic, PZT, has been studied using the double torsion technique. The effects of testing environment and temperature, as well as the state of poling in the material, have been characterized in detail. Tests run in water and in environments inert with respect to water such as toluene, mineral oil and Freon, a corona supperssant, have established that water enhances slow crack propagation in PZT. Fracture has also been found to depend sensitively...
Topics: DTIC Archive, Bruce,J G, HONEYWELL INC BLOOMINGTON MINN CORPORATE MATERIAL SCIENCES CENTER,...
This study primarily investigated the electro-mechanical fatigue behavior of the embedded piezoelectric actuators in graphite/epoxy laminate with a lay-up of 0 \ +/- 45 \ 90s. A secondary focus was the investigation of the mechanical fatigue effects of the 0 \ 0 \ +/- 45 \ 0 \ 0 \ 90s laminate with embedded PZT under tensile loading. All the fatigue tests were conducted with a triangular loading waveform which had a frequency of 10 Hz and with R=0. 1. In the electro-mechanical testing, the...
Topics: DTIC Archive, Hsu, Tse Lin, AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH, *LAMINATES,...
Six categories of active optical materials were found to qualify as potential large-aperture optical modulator material candidates. Two of these, the electro-optical linear Pockels lithium niobate crystals and the ferroelectric ceramic lead lanthanum zirconate titanate wafers showed real promise. Both of these satisfy the requirements of field of view, optical quality, frequency response, and economic availability, and both performed above expectations when tested in an actual optical...
Topics: DTIC Archive, Bocker, R. P., NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA, *CERAMIC MATERIALS, *LIGHT...
This combined Seventh, Eighth, Ninth and Tenth Quarterly report for Contract DAAB07-76-C-0008 describes the progress and status of this program to establish a cost-effective production capability for piezoelectric, ceramic transformers. The problems encountered in the confirmatory build portion of the program are described. After considerable effort on the many problems associated with the 25mm PET's, it was concluded that the costs associated with the construction of these units would not...
Topics: DTIC Archive, Harrison,William B, HONEYWELL INC GOLDEN VALLEY MINN CERAMICS CENTER, *PIEZOELECTRIC...
The deposition of ceramic coatings on gas turbine hot section components by high-rate sputtering was investigated. Stabilized zirconia was the primary ceramic used, however some work was done with magnesium zirconate. The main thrust of the program was the development of methods to improve coating adherence by accommodation of the strain due to the expansivity difference between zirconia and the superalloy components. The use of a graded composition interlayer was the only method which proved...
Topics: DTIC Archive, Busch,R, BATTELLE PACIFIC NORTHWEST LABS RICHLAND WASH, *METAL COATINGS, *DEPOSITION,...
The absorption spectra of chromium and nickel at octahedrsl sites in a zirconium barium fluoride glass are analyzed and compared with vitreous and crystalline mixed oxides, suggesting slightly longer chromium fluoride and nickel fluoride distances than in crystalline fluorides. Laser properties were calculated for rare earth ions in fluoride glass. Pumping efficiencies, lifetimes of excited and terminal levels, and stimulated peak cross sections are presented. Multiphonon relaxation are shown...
Topics: DTIC Archive, Reisfield,Renata, HEBREW UNIV JERUSALEM (ISRAEL), *ABSORPTION SPECTRA, *FLUORIDES,...
ZrO2, as derived from three zircon source minerals and many process variations, was physically and chemically analyzed. The impact of the ZrO2 variations obtained was then evaluated in both dry and wet blended lead zirconate-lead titanate, high drive type piezoelectric compositions. Proper purification and blending of the ZrO2 is shown to yield PZ-PT material with uniform low and high drive piezoelectric behavior. Single precipitated ZrO2 and dry blending are shown to be highly variable...
Topics: DTIC Archive, Harrison,W B, HONEYWELL INC MINNEAPOLIS MN DEFENSE ELECTRONICS DIV, *PIEZOELECTRIC...
A 14 month study by Ceramatec, with a subcontract to the University of Utah, was initiated in order to determine if ferroelastic switching contributes to toughening in ceramic materials. Domain switching in ZrO2 single crystals (heat treated to minimize transformation) at 1400 C was used to show that ferroelastic switching is a process which occurs at temperatures in excess of the monoclinic to tetragonal transformation temperature. These data, coupled with fracture toughness measurements of 8...
Topics: DTIC Archive, Cutler, Raymond A, CERAMATEC INC SALT LAKE CITY UT, *CERAMIC MATERIALS, ALUMINATES,...
Dielectric measurements of strontium titanate and lead titanate zirconate ceramics are conducted at microwave frequencies using a cylindrical resonant cavity in the TE(sub 011) mode. The perturbations of the electric field are recorded in terms of the frequency shift and Q-changes of the cavity signal. Slater's perturbation equations are used to calculate e' and e" of the dielectric constant as a function of temperature and frequency.
Topics: NASA Technical Reports Server (NTRS), CAVITY RESONATORS, CERAMICS, CYLINDRICAL BODIES, DIELECTRICS,...
The major sources of extrinsic absorption and scattering losses in fluorozirconate glasses and fibers have been identified. The origin of transition element impurities has been determined and a new separation process for their removal has been developed. A new reactive atmosphere process for reducing anion impurities is currently in use. Hydroxide contamination from atmospheric water has been recognized and glass processing and rod casting is being conducted in a specially designed atmosphere...
Topics: DTIC Archive, GEO-CENTERS INC NEWTON UPPER FALLS MA, *Fiber optics, *Optical glass, Absorption,...
An axial magnetic field of 0.1T was applied to ZrF4-BaF2-LaF3-AlF3-NaF (ZBLAN) fibers during heating to the glass crystallization temperature. Scanning electron microscopy and x-ray diffraction were used to identify crystal phases. It was shown that fibers exposed to the magnetic field did not crystallize while fibers not exposed to the field did crystallize. A hypothesis based on magnetic work was proposed to explain the results and tested by measuring the magnetic susceptibilities of the...
Topics: NASA Technical Reports Server (NTRS), CRYSTALLIZATION, GLASS, MAGNETIC EFFECTS, ZIRCONATES,...
Pyrochlore oxides have most of the relevant attributes for use as next generation thermal barrier coatings such as phase stability, low sintering kinetics and low thermal conductivity. One of the issues with the pyrochlore oxides is their lower toughness and therefore higher erosion rate compared to the current state-of-the-art TBC material, yttria (6 to 8 wt%) stabilized zirconia (YSZ). In this work, sintering characteristics were investigated for novel multilayered coating consisted of...
Topics: NASA Technical Reports Server (NTRS), SINTERING, FLAT LAYERS, REFRACTORY COATINGS, TEMPERATURE...
Research has been carried out on two families of solids. The first one involves fluoride, chloride and bromide glasses. The second one involves microporous silica glass impregnated with organic polymers as well as inorganic crystals. The viscosity, vibrational spectra, chemical durability, fiber preparation and effects on oxygen on the properties of fluorozirconates have been studied. A number of new halide glasses were discovered. Microporous silica glass impregnated with PMMA was found to be...
Topics: DTIC Archive, Mackenzie, John D., CALIFORNIA UNIV LOS ANGELES SCHOOL OF ENGINEERING AND APPLIED...
Recent developments in cooling thulium-doped heavy-metal fluoride glass are presented. Thulium-doped fluorozirconate (ZBLANP) is cooled to 19 K below ambient with a multiple-pass pump scheme. This represents over an order of magnitude increase from the previously reported single-pass geometry. The results agree with a simple model for anti-Stokes fluorescence cooling that includes considerations of quantum efficiency and parasitic heating mechanisms. Issues relating to a practical optical...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *GLASS, *LASERS, ABSORPTION SPECTRA, COOLING, DOPING,...
The improvement of titanate dielectrics by high temperature fluorination presents a problem in composition and treatment involving narrow working limits. For many compositions the fluorination treatment is critical and one can easily over or under fluorinate. Capacitor discs of high K composition were fluorinated by pushing setters containing the discs through a tunnel kiln treated with a single charge of volatile fluorides. This resulted in a complete range of fluorination treatment during the...
Topics: DTIC Archive, Nordquist, L E, CORNELL-DUBILIER ELECTRIC CORP NEW BEDFORD MA, BARIUM COMPOUNDS,...
A method of producing fully reacted, homogeneous lead zirconate titanate powders including all the technologically important property modifying additives is described. The method involves reacting mixture of powders of the components together with a eutectic NaCl-KCl mixture at a temperature where the salt is molten. The properties of piezoelectric ceramics made of such powders are compared to data from ceramics fabricated from powder made by calcination. Ceramics made from molten salt...
Topics: DTIC Archive, Rosolowski,J H, GENERAL ELECTRIC CORPORATE RESEARCH AND DEVELOPMENT SCHENECTADY N Y,...
A method of producing homogeneous, fully reacted lead zirconate titanate powder, including additive elements, by reaction of the oxides of the constituent metals in a molten salt solvent was developed. Ceramics fired from different batches of powder made in this was showed good batch-to-batch reproducibility of electrical and piezoelectrical properties. Investigation of the influence on the properties of the resulting ceramic of variations in the way such powder is prepared for pressing and...
Topics: DTIC Archive, Rosolowski,J H, GENERAL ELECTRIC CORPORATE RESEARCH AND DEVELOPMENT SCHENECTADY NY,...
Four coating materials have shown the ability to increase the electrical lifetime of PZT ceramic. A strong recommendation was made that Humiseal 2A53 be used for an insulating coating material on the PZT ceramic in the AN/SQS-56 transducer instead of the Conap EN-2 used previously. Long-term water permeation experiments give initial indications that sodium chloride is not carried through the transducer elastomer. The composition of the elastomer is not significantly affected. DI water does not...
Topics: DTIC Archive, Timme, R W, NAVAL RESEARCH LAB WASHINGTON DC, *RELIABILITY, *SONAR TRANSDUCERS,...
Gas gun impact techniques have been used to investigate the electrical response of shock-depoled PZT 56/44 ferroelectric ceramic disks in the stress range from 0.7 to 8.8 GPa. External short-circuit current pulses were measured as the shock wave propagated axially through the disk in a direction either parallel or antiparallel to the remanent polarization vector. Complete charge release was not observed in any of the shots. About 82% of the available charge was released for both orientations in...
Topics: DTIC Archive, Mock, W., Jr., NAVAL SURFACE WEAPONS CENTER DAHLGREN LAB VA, *FERROELECTRIC...
Electrical equations have been derived for the ideal response of normal-mode shock-depoled PZT ferroelectric ceramics with resistive, capacitive, and inductive loads. It was assumed in the analysis that charge was released from the PZT material completely and instantaneously at the shock front. Both rectangular and hollow-cylinder shapes were considered for the PZT unit. Expressions for the charge, voltage, current, and energy in the circuit were obtained for times during and after the...
Topics: DTIC Archive, Mock,W , Jr, NAVAL SURFACE WEAPONS CENTER DAHLGREN LAB VA, *CERAMIC MATERIALS,...
A series of omnidirectional reference transducers for the frequency ranges from 1 Hz to 200 kHz when used as a hydrophone and from 2 to 200 kHz when used as a projector has been developed by the Naval Research Laboratory's Underwater Sound Reference Detachment in Orlando, Florida. The sensitive elements are all piezoelectric lead zirconate - lead titanate PZT-4 hollow spheres encapsulated in polyurethane.
Topics: DTIC Archive, Ivey, L. E., NAVAL RESEARCH LAB WASHINGTON DC, *OMNIDIRECTIONAL, *UNDERWATER SOUND...
The aims of this research were the scientific understanding of the environmental degradation of thermal barrier systems by molten deposits, as relevant to the US Navy aircraft and marine engines, and the application of this understanding to develop mitigation strategies. The program had two thrusts, one addressing molten deposits of calcium-magnesium alumino silicates (CMAS), and the other corrosive sulfate/vanadate (S/V) melts resulting from salt ingestion combined with fuel contaminants. In...
Topics: DTIC Archive, Levi, Carlos G, CALIFORNIA UNIV SANTA BARBARA DEPT OF MATERIALS, *ENVIRONMENTS,...
This document provides results of improvements of the quality of laser-crystallized silicon film of (lead lanthanum zirconate titanate). Dual- beam crystallization to optimize the PLZT film growth conditions by magnetron sputtering was used to study different GaAs growth conditions on sapphire and to measure various organic electro-optic modulator characteristics provided by Celanese. Keywords: Laser-crystallized silicon film, Spatial light modulators, GaAs, Gallium arsenide.
Topics: DTIC Archive, SAN DIEGO STATE UNIV FOUNDATION CA, *SPATIAL DISTRIBUTION, ELECTROOPTICS,...
Lead zirconate titanate (PZT) 56/44 ferroelectric ceramic materials have been shock depoled in the normal mode with capacitive loads. The shock waves were obtained via explosive plane wave techniques and shock stress attenuators. A series of explosive shock-stress attenuation experiments using manganin gauges was performed to determine the stress amplitudes obtainable with the various attenuators. The PZT material was shock loaded in the stress range from 4.6 to 13.1 GPa. Pulse powers of...
Topics: DTIC Archive, Holt,W. H., NAVAL SURFACE WEAPONS CENTER DAHLGREN VA, *EXPLOSIVES, *CERAMIC...
Work presented includes: the oxidation kinetics of iridium and rhodium; the permeability of ZrSiO4, ZrO2, ThO2, Al2O3, and BeO to oxygen; an investigation of the iridium-carbon system by means of high temperature X-ray diffraction techniques and the deposition of iridium on graphite; the volatility of HfO2, ZrO2, ThO2, ThZrO4, SrZrO3, BaZrO3, ZrSiO4, and HfSiO4 in the presence of water vapor; the chemical kinetics of the carbothermic reduction of ZrO2, ThO2, HfO2, ThZrO4, and HfSiO4; the...
Topics: DTIC Archive, Criscione, John M, UNION CARBIDE CORP PARMA OH, *REFRACTORY COATINGS, *GRAPHITE,...
Ferroelastic toughening was identified as a viable mechanism for toughening ceramics. Domain structure and domain switching was identified by x- ray diffraction, transmission optical microscopy, and transmission electron microscopy in zirconia, lead zirconate titanate and gadolinium molybdata. Switching in compression was observed at stresses greater than 600 MPa and at 400 MPa in tension for polycrystalline t'-zirconia. Domain switching contributes to toughness, as evidenced by data for...
Topics: DTIC Archive, Cutler, Raymond A, CERAMATEC INC SALT LAKE CITY UT, *MECHANICAL PROPERTIES, *CERAMIC...
A preliminary evaluation was performed on a prototype Surface Mode Liquid Crystal Shutter (SMLCS) device manufactured by Optical Shields, Inc., in order to determine whether such a device could provide equal or improved nuclear flashblindness protection (NFP) over the currently used EEU/2P lanthanum- modified lead zirconate titanate (PLZT) goggles manufactured by Honeywell. Life support, Nuclear flash, Optical countermeasures.
Topics: DTIC Archive, Mayo, Michael W, ARMSTRONG LAB BROOKS AFB TX OCCUPATIONAL AND ENVIRONMENTAL HEALTH...
The use of passive piezoelectric damping using PZT ceramics has been demonstrated in theory and the number of experiments. The effort was multifaceted. For application of the shunted passive piezoelectric damping of structural composites, piezoelectric ceramic fibers (PZT family) of several tens of micron diameter were produced using sol gel spinning process. Since these fibers were not strong enough to withstand handling for continuous poling process, slurry extruded PZT MicroRods,(12O um in...
Topics: DTIC Archive, Yoshikawa, Shoko, PENNSYLVANIA STATE UNIV UNIVERSITY PARK MATERIALS RESEARCH LAB,...
The year 2 effort was divided between experimental characterization of the constitutive behavior of ferroelectric ceramics and reliability of actuators constructed from these materials. Key results of the study of the constitutive behavior under combined stress and electric field loading were the ability to obtain over 3000 microstrain from PZT without excessive hysteresis or cracking and the characterization of several compositions of PZT under high field and high stress loading. Key results...
Topics: DTIC Archive, Lynch, Christopher S., GEORGIA INST OF TECH ATLANTA SCHOOL OFMECHANICAL ENGINEERING,...
The objective of this program was the understanding of the role of alloying elements in promoting ductility in BCC metals. The program considered the roles of both increased cohesive strength of solids and enhanced plastic deformation in improving the resistance of a solid to fracture. Various approaches were used to evaluate changes that could affect the fracture behavior. These included estimates of true surface energy and fracture stress using interatomic potential functions, and the effect...
Topics: DTIC Archive, Stein,D F, Shannette,G W, MICHIGAN TECHNOLOGICAL UNIV HOUGHTON, *PLASTIC DEFORMATION,...
The second Quarterly Report for Contract DAAB07-76-C-0008 describes the progress and status of this program to establish a cost-effective production capability for 18mm and 25 mm piezoelectric ceramic transformers. Progress toward building the first engineering samples is reviewed and the interconnection techniques for the 18mm package are discussed. (Author)
Topics: DTIC Archive, Harrison, William B, HONEYWELL INC NEW HOPE MN CERAMICS CENTER, *PIEZOELECTRIC...
This Final Technical Report covers the integration of oxide ferroelectric thin films (e.g. bismuth titanate = Bi4Ti3Ol2 = BTO or lead zirconate titanate = PZT) into the gate dielectric of a metal-insulator-silicon field effect transistor (MISFET), capable of functioning in a non-volatile, non- destructive readout (NDRO) ferroelectric random access memory (FERRAM). Also provided is a detailed description of the test vehicles implemented for the study of fabrication process integration and...
Topics: DTIC Archive, Lampe, Donald R, WESTINGHOUSE ELECTRIC CORP BALTIMORE MD ELECTRONIC SYSTEMS SUPPORT...
