Download or read book Shock Initiation Experiments on Ratchet Grown PBX 9502 written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This study compares the shock initiation behavior of PBX 9502 pressed to less than nominal density (nominal density is 1.890 ± 0.005 g/cm3) with PBX 9502 pressed to nominal density and then ''ratchet grown'' to low density. PBX 9502 is an insensitive plastic bonded explosive consisting of 95 weight % dry-aminated tri-amino-tri-nitro-benzene (TATB) and 5 weight % Kel-F 800 plastic binder. ''Ratchet growth'' - an irreversible increase in specific volume - occurs when an explosive based on TATB is temperature cycled. The design of our study is as follows: PBX 9502, all from the same lot, received the following four treatments. Samples in the first group were pressed to less than nominal density. These were not ratchet grown and used as a baseline. Samples in the second group were pressed to nominal density and then ratchet grown by temperature cycling 30 times between -54 C and +80 C. Samples in the final group were pressed to nominal density and cut into 100 mm by 25.4 mm diameter cylinders. During thermal cycling the cylinders were axially constrained by a 100 psi load. Samples for shock initiation experiments were cut perpendicular (disks) and parallel (slabs) to the axial load. The four sample groups can be summarized with the terms pressed low, ratchet grown/no load, axial load/disks, and axial load/slabs. All samples were shock initiated with nearly identical inputs in plate impact experiments carried out on a gas gun. Wave profiles were measured after propagation through 3, 4, 5, and 6 mm of explosive. Side by side comparison of wave profiles from different samples is used as a measure of relative sensitivity. All reduced density samples were more shock sensitive than nominal density PBX 9502. Differences in shock sensitivity between ratchet grown and pressed to low density PBX 9502 were small, but the low density pressings are slightly more sensitive than the ratchet grown samples.
Download or read book Shock Initiation of PBX 9502 at Elevated Temperatures written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The shock sensitivity of PBX-9502 is known to change with temperature. Both volume expansion and increased internal energy may contribute to theis phenomenon. PBX-9502 was heated and its initiation and detonation behavior was examined, using MI and shock tracker gauging on a light gas gun. Sensitivity and reactive wave profiles were measured. Complementary experiments were done on PBX-9502 made to undergo ``ratchet growth``, or non-reversible anisotropic thermal expansion, under carefully controlled thermal cycling. This process causes noticeable size changes and significant changes in sensitivity. Sensitivity and reactive wave profiles are discussed in terms of density and microscopic material morphology.
Download or read book Ignition and Growth Modeling of the Shock Initiation of PBX 9502 at 55C and 196C written by and published by . This book was released on 2015 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Shock Compression of Condensed Matter 1995 written by S. C. Schmidt and published by Springer. This book was released on 1996 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Conference of the American Physical Society Topical Group on shock compression of condensed matter.
Download or read book Shock Initiation of PBX 9502 EDC 35 and LX 17 written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ratchet Growth in PBX 9502 written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SHOCK INITIATION EXPERIMENTS ON PBX 9501 EXPLOSIVE AT PRESSURES BELOW 3 GPa WITH ASSOCIATED IGNITION AND GROWTH MODELING written by and published by . This book was released on 2007 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock initiation experiments on the explosive PBX 9501 (95% HMX, 2.5% estane, and 2.5% nitroplasticizer by weight) were performed at pressures below 3 GPa to obtain in-situ pressure gauge data, run-distance-to-detonation thresholds, and Ignition and Growth modeling parameters. Propellant driven gas guns (101 mm and 155 mm) were utilized to initiate the PBX 9501 explosive with manganin piezoresistive pressure gauge packages placed between sample slices. The run-distance-to-detonation points on the Pop-plot for these experiments showed agreement with previously published data and Ignition and Growth modeling parameters were obtained with a good fit to the experimental data. This parameter set will allow accurate code predictions to be calculated for safety scenarios in the low-pressure regime (below 3 GPa) involving PBX 9501 explosive.
Download or read book PBX 9502 Ratchet Growth Experiments on a Dilatometer written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A Netzsch dilatometer has been used to probe the ratchet growth response of TATB-containing PBX 9502. Preliminary data are presented, showing test reproducibility and examining possible effects of density and/or the specific sequencing of different thermal ranges. We have also shown effects of thermal ramp rate on the test data, likely due to thermal equilibrium of the specimen environment.
Download or read book Shock Compression of Condensed Matter 2009 written by Mark L. Elert and published by American Institute of Physics. This book was released on 2009-12-22 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume embodies the most recent research on shock compression of condensed matter, and includes 363 plenary, invited and contributed papers on topics including equation of state, phase transitions, chemical reactions, warm dense matter, fracture, geophysics and planetary science, energetic materials, optical studies, materials modeling, and recent experimental developments in the field of shock compression of condensed matter.
Download or read book SHOCK INITIATION EXPERIMENTS PLUS IGNITION AND GROWTH MODELING OF DAMAGED LX 04 CHARGES written by and published by . This book was released on 2009 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX and 15% Viton by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. The LX-04 charges were damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermal damaged LX-04 charges were heated to 190 C for a long enough time for the beta to delta phase transition to occur and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while the thermally damaged LX-04 was much more shock sensitive. The pristine LX-04 Ignition and Growth model, modified only by igniting a larger amount of explosive during shock compression based on the damaged charge density, accurately calculated the increased shock sensitivity of the three damaged charges.
Download or read book Shock Initiation Study of PBX 9404 written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure-field histories during the sustained and short-duration shock initiation of PBX-9404 explosive (plastic-bonded HMX) have been determined with embedded Manganin gauges. Numerical integration of the conservation relations and an assumed equation of state are used to obtain the decomposition histories during the initiation process. In both cases, this process is effected by reaction originating near the impact face producing pressure pulses that overtake the shock front and enhance its strength, leading to an abrupt transition to detonation. Correlation of reaction rates to state variables suggest an Arrhenius rate form, modified to include a dependence on shock strength and an induction time. This rate is used in computer simulations of several other initiation experiments on PBX-9404.
Download or read book Double Shock Experiments and Modeling in PBX 9502 written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Static Compression of Energetic Materials written by Suhithi M. Peiris and published by Springer Science & Business Media. This book was released on 2009-01-03 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developing and testing novel energetic materials is an expanding branch of the materials sciences. Reaction, detonation or explosion of such materials invariably produce extremely high pressures and temperatures. To study the equations-of-state (EOS) of energetic materials in extreme regimes both shock and static high pressure studies are required. The present volume is an introduction and review of theoretical, experimental and numerical aspects of static compression of such materials. Chapter 1 introduces the basic experimental tool, the diamond anvil pressure cell and the observational techniques used with it such as optical microscopy, infrared spectrometry and x-ray diffraction. Chapter 2 outlines the principles of high-nitrogen energetic materials synthesis. Chapters 3 and 4, examine and compare various EOS formalisms and data fitting for crystalline and non-crystalline materials, respectively. Chapter 5 details the reaction kinetics of detonating energetic materials. Chapter 6 investigates the interplay between static and dynamic (shock) studies. Finally, Chapters 7 and 8 introduce numerical simulations: molecular dynamics of energetic materials under either hydrostatic or uni-axial stress and ab-inito treatments of defects in crystalline materials. This timely volume meets the growing demand for a state-of-the art introduction and review of the most relevant aspects of static compression of energetic materials and will be a valuable reference to researchers and scientists working in academic, industrial and governmental research laboratories.
Download or read book SHOCK INITIATION EXPERIMENTS AND MODELING OF COMPOSITION B AND C 4 written by F. Garcia and published by . This book was released on 2006 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock initiation experiments on the explosives Composition B and C-4 were performed to obtain in-situ pressure gauge data for the purpose of determining the Ignition and Growth reactive flow model with proper modeling parameters. A 101 mm diameter propellant driven gas gun was utilized to initiate the explosive charges containing manganin piezoresistive pressure gauge packages embedded in the explosive sample. Experimental data provided new information on the shock velocity versus particle velocity relationship for each of the investigated materials in their respective pressure range. The run-distance-to-detonation points on the Pop-plot for these experiments showed agreement with previously published data, and Ignition and Growth modeling calculations resulted in a good fit to the experimental data. These experimental data were used to determine Ignition and Growth reactive flow model parameters for these explosives. Identical ignition and growth reaction rate parameters were used for C-4 and Composition B, and the Composition B model also included a third reaction rate to simulate the completion of reaction by the TNT component. The Composition B model was then tested on existing short pulse duration, gap test, and projectile impact shock initiation with good results. This Composition B model can be applied to shock initiation scenarios that have not or cannot be tested experimentally with a high level of confidence in its predictions.
Download or read book SHOCK INITIATION EXPERIMENTS ON THE TATB BASED EXPLOSIVE RX 03 GO WITH IGNITION AND GROWTH MODELING written by and published by . This book was released on 2009 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock initiation experiments on the TATB based explosive RX-03-GO (92.5% TATB, 7.5% Cytop A by weight) were performed to obtain in-situ pressure gauge data, characterize the run-distance-to-detonation behavior, and calculate Ignition and Growth modeling parameters. A 101 mm diameter propellant driven gas gun was utilized to initiate the explosive sample with manganin piezoresistive pressure gauge packages placed between sample slices. The RX-03-GO formulation utilized is similar to that of LX-17 (92.5% TATB, 7.5% Kel-f by weight) with the notable differences of a new binder material and TATB that has been dissolved and recrystallized in order to improve the purity and morphology. The shock sensitivity will be compared with that of prior data on LX-17 and other TATB formulations. Ignition and Growth modeling parameters were obtained with a reasonable fit to the experimental data.
Download or read book Preshock Desensitization of PBX Explosives written by and published by . This book was released on 1993 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preshocking delays initiation of PBX-9404 and PBX-9501, relative to unshocked material. In PBX-9404 preshock experiments, a first shock of 2.3 GPa was followed 0.65 [mu]s later by a second shock of 5.6 GPa. In PBX-9501, a preshock of 2.8 GPa and 0.32 us duration was followed by an initiating shock of 6.0 GPA. Both PBX explosives show clear desensitization while the preshock persists. In PBX-9404, initiation of detonation occurs nearly as anticipated for the material, after coalescence of the preshock and main shock into a single wave. Multiple embedded magnetic gauges were used to measure the shock histories. Our data indicates a slightly longer run to detonation than expected, even though a single wave is initiating the material. A slight stress reduction at coalescence, as required by the shock dynamics, may be responsible for the overrun. A reactive waste is clearly evident while the preshock persists. The long run to detonation indicates that this reactive wave is not driving the initiation. A set of four preshock experiments were preformed on PBX-9502, which is unreactive at these pressures, to investigate the shock dynamics of the two waves in the HE.
Download or read book SHOCK INITIATION EXPERIMENTS ON THE LLM 105 EXPLOSIVE RX 55 AA AT 25 C AND 150 C WITH IGNITION AND GROWTH MODELING written by and published by . This book was released on 2007 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock initiation experiments on the LLM-105 based explosive RX-55-AA (95% LLM-105, 5% Viton by weight) were performed at 25 C and 150 C to obtain in-situ pressure gauge data, run-distance-to-detonation thresholds, and Ignition and Growth modeling parameters. A 101 mm diameter propellant driven gas gun was utilized to initiate the explosive sample with manganin piezoresistive pressure gauge packages placed between sample slices. The run-distance-to-detonation points on the Pop-plot for these experiments showed agreement at 25 C with previously published data on a similar LLM-105 based formulation RX-55-AB as well as a slight sensitivity increase at elevated temperature (150 C) as expected. Ignition and Growth modeling parameters were obtained with a reasonable fit to the experimental data.
