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Hard target penetrator explosive development optimization of fragment, blast and survivability properties of explosives for hard target applications

Description: Several new explosives have been developed for hard target and related applications. Materials having energy densities as high as 20 KJ/cc have been made. Mid-scale field trials have been carried out at Eglin Air Force Base. Fragmentation improvements 150% that of Tritonal have been attained.
Date: May 1, 1997
Creator: Simpson, R. L., LLNL
Partner: UNT Libraries Government Documents Department

Characteristics and development report for the SA3871 Intent Controller application specific integrated circuit (ASIC)

Description: This report describes the design and development activities that were involved in the SA3871 Intent Controller ASIC. The SA3871 is a digital gate array component developed for the MC4396 Trajectory Sensing Signal Generator for use in the B61-3/4/10 system as well as a possible future B61-MAST system.
Date: August 1, 1995
Creator: Simpson, R.L. & Meyer, B.T.
Partner: UNT Libraries Government Documents Department

The unusual stability of TATB (1,3,5-triamino-2,4,6-trinitrobenzene): A review of the scientific literature

Description: This review is intended as an up-to-date review of the scientific literature on TATB since its discovery as a high explosive. In particular, it focuses on clarifying our current understanding of the relationship between the structure of TATB and its unique thermal stability. We review a large number of different publications by many authors. A small portion of the work on TATB'' presented actually consists of experimental studies on TATB formulated as PBX-9502 or as LX-17. Where relevant, this distinction is indicated. However, inasmuch as this review focuses on thermal response and the relationship of chemical reactivity to the molecular and lattice structure of TATB as a pure material, results from these other formulations may not be directly applicable, and in general we have omitted them. 4 refs.
Date: July 4, 1990
Creator: Rice, S.F. & Simpson, R.L.
Partner: UNT Libraries Government Documents Department

Development of Non-hazardous Explosives for Security Training and Testing (NESTT)

Description: The security force at the Lawrence Livermore National Laboratory (LLNL) routinely used canines to search for explosives and other contraband substances. The use of threat quantities of explosive for realistic training in populated or sensitive Laboratory areas has not been permitted because of the hazard. To overcome this limitation a series of non-hazardous materials with authentic signatures have been prepared and evaluated. A series of materials has been prepared that have authentic properties of explosives but are non-hazardous. These NESTT materials are prepared by coating a few micron thick layer of an explosive on a non-reactive substrate. This produces a formulation with an authentic vapor and molecular signature. Authentic x-ray and oxygen/nitrogen density signatures are obtained through the appropriate choice of a substrate. The signatures of NESTT TNT and NESTT Comp. C-4 have been verified by instrument and canine (K-9) detection in a Beta Test Program.
Date: January 1, 1996
Creator: Kury, J.W.; Simpson, R.L. & Hallowell, S.F.
Partner: UNT Libraries Government Documents Department

Shock initiation of 2,4-dinitroimidazole (2,4-DNI)

Description: The shock sensitivity of the pressed solid explosive 2,4-dinitroimidazole (2,4-DNI) was determined using the embedded manganin pressure gauge technique. At an initial shock pressure of 2 GPa, several microseconds were required before any exothermic reaction was observed. At 4 GPa, 2,4-DNI reacted more rapidly but did not transition to detonation at the 12 mm deep gauge position. At 6 GPa, detonation occurred in less than 6 mm of shock propagation. Thus, 2,4-DNI is more shock sensitive than TATB-based explosives but is considerably less shock sensitive than HMX-based explosives. An Ignition and Growth reactive flow model for 2,4-DNI based on these gauge records showed that 2,4-DNI exhibits shock initiation characteristics similar to TATB but reacts faster. The chemical structure of 2,4-DNI suggests that it may exhibit thermal decomposition reactions similar to nitroguanine and explosives with similar ring structures, such as ANTA and NTO.
Date: July 19, 1995
Creator: Urtiew, P.A.; Tarver, C.M. & Simpson, R.L.
Partner: UNT Libraries Government Documents Department

Shock initiation of 1,3,3-trinitroazetidine (TNAZ)

Description: The shock sensitivity of the pressed solid explosive 1,3,3-trinitroazetidine (TNAZ) was determined using the embedded manganin pressure gauge technique. At an initial pressure of 1.3 GPa, pressure buildup (exothermic reaction) was observed after ten {mu}s. At 2 GPa, TNAZ reacted rapidly and transitioned to detonation in approximately 13 mm. At 3.6 GPa, detonation occurred in less than 6 mm of shock propagation. Thus, pure TNAZ is more shock sensitive than HMX-based explosives but less shock sensitive than PETN-based explosives. The shocked TNAZ exhibited little reaction directly behind the shock front, followed by an extremely rapid reaction. This reaction caused both a detonation wave and a retonation wave in the partially decomposed TNAZ. An Ignition and Growth reactive model for TNAZ was developed to help understand this complex initiation phenomenon.
Date: July 19, 1995
Creator: Simpson, R.L.; Urtiew, P.A. & Tarver, C.M.
Partner: UNT Libraries Government Documents Department

Porous silicon structural evolution from in-situ luminescence and Raman measurements

Description: The authors performed in-situ photoluminescence and Raman measurements on an anodized silicon surface in the HF/ethanol solution used for anodization. The porous silicon thereby produced, while resident in HF/ethanol, does not immediately exhibit intense photoluminescence. Intense photoluminescence develops spontaneously in HF/ethanol after 18--24 hours or with replacement of the HF/ethanol with water. These results support a quantum confinement mechanism in which exciton migration to traps and nonradiative recombination dominates the de-excitation pathways until silicon nanocrystallites are physically separated and energetically decoupled by hydrofluoric acid etching or surface oxidation. The porous silicon surface, as produced by anodization, shows large differences in photoluminescence intensity and peak wavelength over millimeter distances. Parallel Raman measurements implicate nanometer-size silicon particles in the photoluminescence mechanism.
Date: May 1, 1996
Creator: Tallant, D.R.; Kelly, M.J.; Guilinger, T.R. & Simpson, R.L.
Partner: UNT Libraries Government Documents Department

Reactive flow model development for PBXW-126 using modern nonlinear optimization methods

Description: The initiation and detonation behavior of PBXW-126 has been characterized and is described. PBXW-126 is a composite explosive consisting of approximately equal amounts of RDX, AP, AL, and NTO with a polyurethane binder. The three term ignition and growth of reaction model parameters (ignition + two growth terms) have been found using nonlinear optimization methods to determine the {open_quotes}best{close_quotes} set of model parameters. The ignition term treats the initiation of up to 0.5% of the RDX The first growth term in the model treats the RDX growth of reaction up to 20% reacted. The second growth term treats the subsequent growth of reaction of the remaining AP/AL/NTO. The unreacted equation of state (EOS) was determined from the wave profiles of embedded gauge tests while the JWL product EOS was determined from cylinder expansion test results. The nonlinear optimization code, NLQPEB/GLO, was used to determine the {open_quotes}best{close_quotes} set of coefficients for the three term Lee-Tarver ignition and growth of reaction model.
Date: August 1, 1995
Creator: Murphy, M.J.; Simpson, R.L. & Urtiew, P.A.
Partner: UNT Libraries Government Documents Department

Shock initiation of an {epsilon}-CL-20-estane formulation

Description: The shock sensitivity of a pressed solid explosive formulation, LX-19, containing 95.2% by weight epsilon phase 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (HNIW) and 4.8% Estane binder, was determined using the wedge test and embedded manganin pressure gauge techniques. This formulation was shown to be slightly more sensitive than LX-14, which contains 95.5% HMX and 4.5% Estane binder. The measured pressure histories for LX-19 were very similar to those obtained using several HMX-inert binder formulations. An Ignition and Growth reactive model for LX-19 was developed which differed from those for HMX-inert binder formulations only by a 25% higher hot spot growth rate.
Date: July 19, 1995
Creator: Tarver, C.M.; Simpson, R.L. & Urtiew, P.A.
Partner: UNT Libraries Government Documents Department

Self-Irradiation Effects on 99Mo Reagents and Products

Description: produced in 1996 and shipped to pharmaceutical houses for evaluation of compatibility with oxime solution used to precipitate `?vfo as the oxime complex is both air and light-sensitive, and containing a black precipitate that forms during shipment, presumably as a result of self- irradiation. Addition of sodium hypochlorite to the product solution prior to shipment prevents precipitate formation, indicating the precipitate is a reduced form of `%lo. to remove any precipitate. Duplicate aliquots of the filtered samples were titrated to a phenolphthalein irradiation and afler standing at room temperature for 86.4 hours. Precipitates were washed to a FTIR analysis of the white precipitate showed it to be alpha benzoin oxime. Since the basic After 86.4 hours, no precipitate had formed in bottles containing sodium hypochlorite. Black precipitate had formed in all bottles that did not contain sodium hypochlorite after 14.4 hours. The precipitate appeared to initially form on the surface of the HDPE sample bottles and Black precipitate was first noticed in sample set 1 after 28.8 hrs' irradiation. No visible sample containing precipitate was kept at room temperature in the original bottle. Precipitate in sample sets 2 and 3. Since no precipitate formed in these bottles, this was equivalent to duplicate samples. Once the precipitate in the 20-mL aliquots that had been set aside had returned to sample sets 1 through 3 and the samples with redissolved precipitate all experienced an average decrease in base strength of 0.013 meq mL-l. Sample 1-C had a decrease of 0.004 meq mL-l and sample 1-D had returned to the initial value of 0.198 meq mL-l. Raman spectra for the black precipitate from samples l-C, 1-D and supplemental sample set 1 Fig. 2. Raman spectra of the black precipitate formed in 9%40 product solutions after 28.8,43.2, 72 and 86.4 hours of `oCo irradiation ...
Date: October 7, 1998
Creator: Carson, S.D.; Garcia, M.J.; McDonald, M.J.; Simpson, R.L. & Tallant, D.R.
Partner: UNT Libraries Government Documents Department

Radiation Chemistry of Simulated (99)Mo Product

Description: PharrnaceuticaI houses that produce {sup 99}Tc/{sup 99}Tc generators have on occasion received {sup 99}Mo that contained a black precipitate. Addition of sodium hypochlorite to product bottles prior to shipment prevents precipitate formation, indicating the precipitate is a reduced form of Mo. The radiation effects of the dose from {sup 99}Mo on the product and product bottle have been determined by irradiating simulated {sup 99}Mo product solutions with the {sup 60}Co source at Sandia National Laboratories' Gamma Irradiation Facility (GE). The GIF experiment successfully generated a black precipitate in amounts sufficient for isolation and analysis by infrared and Rrunan spectroscopy. Changes in the pH of the basic {sup 99}Mo product solution during irradiation were monitored by titration. ResuIts of these analyses and the nature of the process that generates the precipitate, a mixture of molybdenum oxides that forms in plastic bottles, but not in glass containers, are discussed.
Date: November 6, 1998
Creator: Carson, S.D.; Garcia, M.J.; McDonald, M.J.; Simpson, R.L. & Tallant, D.R.
Partner: UNT Libraries Government Documents Department

Residual stress and Raman spectra of laser deposited highly-tetrahedral-coordinated-amorphous-carbon films

Description: We are studying carbon thin films by using a pulsed excimer laser to ablate pyrolytic graphite targets to form highly tetrahedral coordinated amorphous carbon ({alpha}t-C) films. These films have been grown on room temperature p-type Si (100) substrates without the intentional incorporation of hydrogen. In order to understand and optimize the growth of {alpha}t-C films, parametric studies of the growth parameters have been performed. We have also introduced various background gases (H{sub 2}, N{sub 2} and Ar) and varied the background gas pressure during deposition. The residual compressive stress levels in the films have been measured and correlated to changes in the Raman spectra of the {alpha}t-C band near 1565 cm{sup {minus}1}. The residual compressive stress falls with gas pressure, indicating a decreasing atomic sp{sup 3}-bonded carbon fraction. We find that reactive gases such as hydrogen and nitrogen significantly alter the Raman spectra at higher pressures. These effects are due to a combination of chemical incorporation of nitrogen and hydrogen into the film as well as collisional cooling of the ablation plume. In contrast, films grown in non-reactive Ar background gases show much less dramatic changes in the Raman spectra at similar pressures.
Date: May 1, 1994
Creator: Friedmann, T. A.; Siegal, M. P.; Tallant, D. R.; Simpson, R. L. & Dominguez, F.
Partner: UNT Libraries Government Documents Department

Preliminary evaluation of non-hazardous explosives for security training and testing (NESTT)

Description: A series of materials has been prepared that have authentic properties of explosives but are non-hazardous. These NESTT materials are prepared by coating a few micron layer of an explosive on a non-reactive substrate. This produces a formulation with an authentic vapor signature. Authentic x-ray and oxygen/nitrogen density signatures can also be obtained through the appropriate choice of substrate. Sensitivity tests on the materials made to date show that they are non-hazardous. One such material is now in use for canine training at the Lawrence Livermore National Laboratory.
Date: September 1, 1993
Creator: Moody, G. L.; Pruneda, C. O.; Simpson, R. L.; Kury, J. W. & Dumais, D. A.
Partner: UNT Libraries Government Documents Department

Characterization of ultradispersed aluminum

Description: Samples of ultradispersed Al were received, which were produced by electrically exploding Al wires in argon. These samples comprised very small particles that were not significantly oxidized and that were stable in air. Particle morphology were studied with SE, micropycnometry, and gas adsorption surface area. Composition were determined using various techniques, as were thermal stability and reaction exotherms. The inexplicable reports of an Al-Ar compound and of an exothermic reaction were not confirmed. The material is a stable, nonoxidized, small-particle, highly reactive form of aluminum that is of interest in energetic materials formulations.
Date: December 8, 1994
Creator: Simpson, R. L.; Maienschein, J. L.; Swansiger, R. W.; Garcia, F. & Darling, D. H.
Partner: UNT Libraries Government Documents Department

Demonstration of enhanced warhead performance with more powerful explosives

Description: Enhanced warhead performance has been demonstrated for several warhead configurations loaded with more powerful explosives. This paper presents experimental results from several warheads loaded with one of the new more powerful explosives, LX-19. The LX-19 formulation is a volume analog to LX-14 (HMX/Estane) that consists of 95.8 wt.% epsilon CL-20 formulated with 4.2 wt.% Estane binder. The LX-19 formulation, characterization, and evaluation efforts presseted in this paper are the result of several studies that have been ongoing since 1991. The warhead configurations that have been tested include a trumpet lined shaped charge, a hemispherical lined shaped cahrge, an EFP charge, and a fragmentation warhead, Performation improvements have been demonstrated with all configurations that were tested.
Date: December 1, 1997
Creator: Murphy, M.J.; Baum, D.; Simpson, R.L.; Monoto, J.; Montesi, L.; Newman, K. et al.
Partner: UNT Libraries Government Documents Department

Sol-gel processing of energetic materials

Description: As part of a new materials effort, we are exploring the use of sol- gel chemistry to manufacture energetic materials. Traditional manufacturing of energetic materials involves processing of granular solids. One application is the production of detonators where powders of energetic material and a binder are typically mixed and compacted at high pressure to make pellets. Performance properties are strongly dependent on particle size distribution, surface area of its constituents, homogeneity of the mix, and void volume. The goal is to produce detonators with fast energy release rate the are insensitive to unintended initiation. In this paper, we report results of our early work in this field of research, including the preparation of detonators from xerogel molding powders and aerogels, comparing the material properties with present state-of-the-art technology.
Date: August 18, 1997
Creator: Tillotson, T.M.; Hrubesh, L.H.; Fox, G.L.; Simpson, R.L.; Lee, R.W.; Swansiger, R.W. et al.
Partner: UNT Libraries Government Documents Department

Characterization of TNAZ

Description: The explosive TNAZ has recently become available in pilot-plant quantities. We have found its small-scale safety properties similar to those of other nitramines. Detonation calorimetry showed TNAZ to have 96% the energy of HMX and 150% of TNT. The shock sensitivity of neat TNAZ is greater than LX-14. A retonation wave was observed when the material was shocked at 2.0 GPa. The initiation behavior of neat TNAZ cannot be classified as either homogeneous or heterogeneous. Six plastic bonded TNAZ-based explosives have been developed for the Army.
Date: December 14, 1994
Creator: Simpson, R. L.; Garza, R. G.; Foltz, M. F.; Ornellas, D. L. & Utriew, P. A.
Partner: UNT Libraries Government Documents Department

Optical Spectroscopic Monitoring of Parachute Yarn Aging

Description: Optical spectroscopic techniques were evaluated as nondestructive monitors of the aging of parachutes in nuclear weapons. We analyzed thermally aged samples of nylon and Kevlar webbing by photoluminescence spectroscopy and reflection spectroscopy. Infrared analysis was also performed to help understand the degradation mechanisms of the polymer materials in the webbing. The photoluminescence and reflection spectra were analyzed by chemometric data treatment techniques to see if aged-induced changes in the spectra correlated to changes in measured tensile strength. A correlation was found between the shapes of the photoluminescent bands and the measured tensile strengths. Photoluminescent spectra can be used to predict the tensile strengths of nylon and Kevlar webbing with sufficient accuracy to categorize the webbing sample as above rated tensile strength, marginal or below rated tensile strength. The instrumentation required to perform the optical spectroscopic measurement can be made rugged, compact and portable. Thus, optical spectroscopic techniques offer a means for nondestructive field monitoring of parachutes in the enduring stockpile/
Date: April 1, 1999
Creator: Tallant, D.R.; Garcia, M.J.; Simpson, R.L.; Behr, V.L.; Whinery, L.D. & Peng, L.W.
Partner: UNT Libraries Government Documents Department

Characterization of carbon nitride films produced by pulsed laser deposition

Description: Carbon Nitride (CN{sub x}) films have been grown by ion-assisted pulsed-laser deposition (IAPLD). Graphite targets were laser ablated while bombarding the substrate with ions from a broad-beam Kaufman-type ion source. Ion voltage, current density, substrate temperature, and feed gas composition (N{sub 2} in Ar) were varied. Resultant films were characterized by Raman. Fourier transform infrared (FTIR), and Rutherford back scattering (RBS) spectroscopy. Samples with {approximately} 30% N/C ratio have been fabricated. The corresponding Raman and FTIR spectra indicate that nitrogen is incorporated into the samples by insertion into sp{sup 2}-bonded structures. A low level of C{identical_to}N triple bonds is also found. As the ion current and voltage are increased with a pure Ar ion beam, Raman peaks associated with nanocrystalline graphite appear in the spectra. Adding low levels of nitrogen to the ion beam first reduces the Raman intensity in the vicinity of the graphite disorder peak without adding detectable amounts of nitrogen to the films (as measured by RBS). At higher nitrogen levels in the ion beam, significant amounts of nitrogen are incorporated into the samples, and the magnitude of the ``disorder`` peak increases. By increasing the temperature of the substrate during deposition, the broad peak due mainly to sp{sup 2}-bonded C-N in the FTIR spectra is shifted to lower wavenumber. This could be interpreted as evidence of single-bonded C-N; however, it is more likely that the character of the sp{sup 2} bonding is changing.
Date: July 1, 1995
Creator: Friedmann, T.A.; Tallant, D.R.; Barbour, J.C.; Sullivan, J.P.; Siegal, M.P.; Simpson, R.L. et al.
Partner: UNT Libraries Government Documents Department

Formulation and Performance of Novel Energetic Nanocomposites and Gas Generators Prepared by Sol-Gel Methods

Description: In the field of composite energetic materials, properties such as ingredient distribution, particle size, and morphology affect both sensitivity and performance. Since the reaction kinetics of composite energetic materials are typically controlled by the mass transport rates between reactants, one would anticipate new and potentially exceptional performance from energetic nanocomposites. We have developed a new method of making nanostructured energetic materials, specifically explosives, propellants, and pyrotechnics, using sol-gel chemistry. A novel sol-gel approach has proven successful in preparing nanostructured metal oxide materials. By introducing a fuel metal, such as aluminum, into the nanostructured metal oxide matrix, energetic materials based on thermite reactions can be fabricated. Two of the metal oxides are tungsten trioxide and iron(III) oxide, both of which are of interest in the field of energetic materials. Due to the versatility of the preparation method, binary oxidizing phases can also be prepared, thus enabling a potential means of controlling the energetic properties of the subsequent nanocomposites. Furthermore, organic additives can also be easily introduced into the nanocomposites for the production of nanostructured gas generators. The resulting nanoscale distribution of all the ingredients displays energetic properties not seen in its micro-scale counterparts due to the expected increase of mass transport rates between the reactants. The unique synthesis methodology, formulations, and performance of these materials will be presented. The degree of control over the burning rate of these nanocomposites afforded by the compositional variation of a binary oxidizing phase will also be discussed. These energetic nanocomposites have the potential for releasing controlled amounts of energy at a controlled rate. Due to the versatility of the synthesis method, a large number of compositions and physical properties can be achieved, resulting in energetic nanocomposites that can be fabricated to meet specific safety and environmental considerations.
Date: March 24, 2005
Creator: Clapsaddle, B J; Zhao, L; Prentice, D; Pantoya, M L; Gash, A E; Satcher Jr., J H et al.
Partner: UNT Libraries Government Documents Department

Cold-Cathodes for Sensors and Vacuum Microelectronics

Description: The aim of this laboratory-directed research and development project was to study amorphous carbon (a-C) thin films for eventual cold-cathode electron emitter applications. The development of robust, cold-cathode emitters are likely to have significant implications for modern technology and possibly launch a new industry: vacuum micro-electronics (VME). The potential impact of VME on Sandia`s National Security missions, such as defense against military threats and economic challenges, is profound. VME enables new microsensors and intrinsically radiation-hard electronics compatible with MOSFET and IMEM technologies. Furthermore, VME is expected to result in a breakthrough technology for the development of high-visibility, low-power flat-panel displays. This work covers four important research areas. First, the authors studied the nature of the C-C bonding structures within these a-C thin films. Second, they determined the changes in the film structures resulting from thermal annealing to simulate the effects of device processing on a-C properties. Third, they performed detailed electrical transport measurements as a function of annealing temperature to correlate changes in transport properties with structural changes and to propose a model for transport in these a-C materials with implications on the nature of electron emission. Finally, they used scanning atom probes to determine important aspects on the nature of emission in a-C.
Date: May 1, 1998
Creator: Siegal, M.P.; Sullivan, J.P.; Tallant, D.R.; Simpson, R.L.; DiNardo, N.J.; Mercer, T.W. et al.
Partner: UNT Libraries Government Documents Department

Deposition of DLC via intense ion beam ablation

Description: Diamond-like carbon films were prepared by high intensity pulsed ion beam ablation of graphite targets. A 350 key, 35 kA, 400 ns pulse width beam, consisting primarily of carbon ions and protons, was focused onto a graphite target at a fluence of 15-45J/cm{sup 2}. Films were deposited onto substrates positioned i.n q n angular array from normal to the target to 90{degrees} off normal. Deposition rates up to 30 nm per pulse, corresponding to an instantaneous deposition rate greater than I mn/sec, have been observed. Electrical resistivities between 1 and 1000 ohm-cm were measured for these films. XRD scans showed that no crystalline structure developed in the films. SEM revealed that the bulk of the films contain material with feature sizes on the order of 100 nm, but micron size particles were deposited as well. Both Raman and electron energy loss spectroscopy indicated significant amounts of sp{sup 3} bonded carbon present in most of the films.
Date: December 31, 1993
Creator: Johnston, G. P.; Tiwari, P.; Rej, D. J.; Davis, H. A.; Waganaar, W. J.; Muenchausen, R. E. et al.
Partner: UNT Libraries Government Documents Department