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Friction, impact, and electrostatic discharge sensitivities of energetic materials

Description: Impact, friction, and electrostatic discharge sensitivities of energetic materials (explosives and pyrotechnics) used or manufactured at Mound were tested by the ''one-shot'' method. The Bruceton statistical method was used to derive 50% initiation levels, and the results were compared. The materials tested include: PETN, HMX, Plastic Bonded Explosives (PBX), CP, TATB, RX26BB, RX26BH, barium styphnate, LX-15, LX-16, Ti/KClO/sub 4/, TiH/sub 0.65//KClO/sub 4/, TiH/sub 1.65//KClO/sub 4/, Fe/KClO/sub 4/, TiH/sub 1.75//B/CaCrO/sub 4/, Ti/B/CaCrO/sub 4/, B/CaCrO/sub 4/, TiH/sub 0.65//2B, TiH/sub 0.65//3B, 2Ti/B, TiH/sub 1.67//2B, Ti/2B, TiH/sub 1/67//3B, Ti/B, and Ti/3B. Some samples were investigated for aging effects, physical variables, and the effect of manufacturing paramters on sensitivities. The results show that in both friction and impact tests, CP and barium styphnate are the most sensitive; TiH/sub 1.65/KClO/sub 4/, LX-15, TATB and its related materials are the least sensitive; and other materials such as PETN and HMX are in the mid-range. In the electrostatic tests of Ti-based pyrotechnics, a decrease of sensitivity with increasing hydrogen concentration was observed. 20 refs., 12 figs., 7 tabs.
Date: May 31, 1985
Creator: Wang, P.S. & Hall, G.F.
Partner: UNT Libraries Government Documents Department

Dissolution of surface oxide layers on titanium and titanium subhydride between 25/sup 0/ and 700/sup 0/C

Description: The surface-sensitive, spectroscopic techniques of Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) have been applied to the study of oxide dissolution on titanium and titanium subhydride. In an earlier study it was shown, using AES, that the rate of oxygen dissolution into titanium increased sharply at about 350/sup 0/C. These data correlated well with physical property measurements that indicated that at these temperatures an exothermic reaction, corresponding to the reaction of free titanium with atmospheric oxygen, was occurring. In the present study the work has been expanded to include studies of TiH/sub x/ (x = 1.15, 1.62). It has been found that dissolution of the native oxide on titanium subhydride occurs at a substantially higher temperature (about 500/sup 0/C) than for titanium. It appears that the outward diffusion of hydrogen is inhibiting the inward diffusion of oxygen on the subhydride samples at temperatures below 500/sup 0/C. Further studies of the dissolution of oxides on titanium at fixed temperatures in the range of 300 to 350/sup 0/C have shown that there is a semi-logarithmic relationship between the surface oxygen level and the time at temperature. This is in agreement with earlier gravimetric studies on titanium oxidation in this temperature range.
Date: January 1, 1981
Creator: Wittberg, T.N. & Wang, P.S.
Partner: UNT Libraries Government Documents Department

Evaluation of concurrent peak responses

Description: This report deals with the problem of combining two or more concurrent responses which are induced by dynamic loads acting on nuclear power plant structures. Specifically, the acceptability of using the square root of the sum of the squares (SRSS) value of peak values as the combined response is investigated. Emphasis is placed on the establishment of a simplified criterion that is convenient and relatively easy to use by design engineers.
Date: January 1, 1983
Creator: Wang, P.C.; Curreri, J. & Reich, M.
Partner: UNT Libraries Government Documents Department

Oxygen diffusion of anodic surface oxide film on titanium studied by Auger electron spectroscopy. [Oxygen diffusivity]

Description: TiO/sub 2/ films of about 1000 A were grown onto titanium foils anodically under galvanostatic conditions at 20 mA/cm/sup 2/ in saturated aqueous solutions of ammonium tetraborate. The samples were then aged at 450, 500, and 550/sup 0/C, and oxygen diffusion was observed by Auger electron spectroscopy (AES) profilings. The oxygen diffusivities were calculated by Fick's Second Law, using the Boltzmann-Matano solution, to be 9.4 x 10/sup -17/, 2.6 x 10/sup -16/, and 1.2 x 10/sup -15/ cm/sup 2//sec at 450, 500, and 550/sup 0/C, respectively. The diffusivities obtained by this method were also compared with those obtained using an exact solution to Fick's Second Law. The activation energy was calculated to be 30 kcal/mole.
Date: January 1, 1982
Creator: Wang, P.S.; Wittberg, T.N. & Keil, R.G.
Partner: UNT Libraries Government Documents Department

Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery Quarterly Report: Q1 FY03

Description: In this quarter, further analysis was done to investigate the difficulty in predicting fracture at the slab ends. The stress concentration created by the notch geometry at the slab ends can accelerate damage and promote fracture at the relatively low strain rates that exist when the notch region is not directly in the roll bite. However, the phenomenological fracture model provided by Alcoa Technical Center (ATC) was calibrated for strain rates characteristic of the rolling process zone and hydrostatic stress states less severe than the leading edge notch. Additional experiments are being performed at ATC to extend the model's range to include the low strain rate, high triaxiality condition. A bug in the parallel code that caused an inconsistent temperature distribution at the slab surface has been identified and Corrected. Currently, more simulations are being performed to validate the model.
Date: February 3, 2003
Creator: Couch, R & Wang, P
Partner: UNT Libraries Government Documents Department

Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery

Description: A model of the 28-inch, laboratory mill at Alcoa Technical Center was constructed, and a preliminary calculation run using an estimated initial ingot size and pass schedule to assess the computational requirements for the simulations and to develop a procedure for adjusting the mill configuration and model boundary conditions between passes. The simulation was run through three passes, and the mechanical and contact thermal boundary conditions appear to be working appropriately.
Date: November 19, 2001
Creator: Couch, R G & Wang, P
Partner: UNT Libraries Government Documents Department

Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery (Quarterly Report: Q3-FY03)

Description: In this quarter, an FEM simulation has been performed to compare the shape of the deformed slab after the 8th reduction pass with the experimental metrology data provided by Alcoa Technical Center (ATC). Also, a bug in the thermal contact algorithm used in parallel processing have been identified and corrected for consistent thermal solutions between the rollers and the slab. The overall shape of the slab at the end of the 8th pass is shown in Figure 1. Comparison of the sectional views at the center plane along the length of the slab for both experiment and simulation, shows that the curvature at the slab mouth at the centerline is slightly higher than the experimental result as shown in Figure 2. We are currently focusing on tuning the parameter values used in the simulation and a more complete parametric study for validation is underway. Also, unexpected fracture occurred along the surface of the slab in the 9th pass as shown in Figure 3. We believe that the reason is due to previously noted inadequacies in the fracture model at low strain rates and high stress triaxiality. We are expecting to receive a modified fracture model based on additional experiment shortly from Alcoa.
Date: July 31, 2003
Creator: Couch, R & Wang, P
Partner: UNT Libraries Government Documents Department

Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery

Description: In this quarter, our primary effort has been focused on model verification, emphasizing on consistency in result for parallel and serial simulation runs, Progress has been made in refining the parallel thermal algorithms and in diminishing discretization effects in the contact region between the rollers and slab. We have received the metrology data of the ingot profile at the end of the fifth pass from Alcoa. Detailed comparisons between the data and the initial simulation result are being performed. Forthcoming from Alcoa are modifications to the fracture model based on additional experiments at lower strain rates. The original fracture model, was implemented in the finite element code, but damage in the rolling simulation was not correct due to the modeling errors at lower strain rates and high stress triaxiality. Validation simulations for the fracture model will continue when the experimentally-based adjustments to the parameter values become available.
Date: May 6, 2003
Creator: Couch, R & Wang, P
Partner: UNT Libraries Government Documents Department

Progress Report FY04 Quarter 1

Description: In this quarter, a simulation has been carried out to validate the FEM model for a production facility mill configuration, focusing on the shape change evolution of the slab. Results of ingot shape evolution for a 13 pass rolling simulation are given in Figure 1. It was observed that the rollover of the slab is strongly dependent on friction. More studies on friction laws may be necessary for more accurate prediction. Another important feature is the mesh dependence of the result. More frequent remeshing may be necessary to be able to capture the deformation behavior more accurately. These issues are currently being investigated. Also, we expect that ATC will provide the refined fracture model to LLNL shortly. Once available, appropriate modifications will be made in the FEM subroutines, and the validation process for slab fracture will continue.
Date: January 29, 2004
Creator: Couch, R G & Wang, P
Partner: UNT Libraries Government Documents Department

Virialization Heating in Galaxy Formation

Description: In a hierarchical picture of galaxy formation virialization continually transforms gravitational potential energy into kinetic energies in the baryonic and dark matter. For the gaseous component the kinetic, turbulent energy is transformed eventually into internal thermal energy through shocks and viscous dissipation. Traditionally this virialization and shock heating has been assumed to occur instantaneously allowing an estimate of the gas temperature to be derived from the virial temperature defined from the embedding dark matter halo velocity dispersion. As the mass grows the virial temperature of a halo grows. Mass accretion hence can be translated into a heating term. We derive this heating rate from the extended Press Schechter formalism and demonstrate its usefulness in semi-analytical models of galaxy formation. Our method is preferable to the traditional approaches in which heating from mass accretion is only modeled implicitly through an instantaneous change in virial temperature. Our formalism can trivially be applied in all current semi-analytical models as the heating term can be computed directly from the underlying merger trees. Our analytic results for the first cooling halos and the transition from cold to hot accretion are in agreement with numerical simulations.
Date: January 17, 2007
Creator: Wang, P. (KIPAC, Menlo Park) & Abel, T. (Santa Barbara, KITP)
Partner: UNT Libraries Government Documents Department

The Dissolution of Native Oxide Films on Titanium for Pyrotechnic Applications

Description: The dissolution of native oxides on Ti were studied over the temperature range 25 degrees - 730 degrees C to determine their role in the pyrotechnic reaction of Ti with KCl0{sub}4. From AES data it was found that the solubility of the oxide in Ti increased sharply at 350 degrees C. High resolution AES scans of the Ti LMM transitions as well as XPS scans of the Ti 2 p level showed that free Ti is present at the surface above 350 degrees C. The O 1s XPS data shows that the surface contains hydroxyl as well as oxide groups. The hydroxide to oxide ratio begins to decrease below 250 degrees C, and at 450 degrees C the remaining oxygen is bound predominatly as oxide. Additionally, the XPS data shows that the dissoluton process proceeds through the formation of titanium suboxides. These AES and XPS results complement physical property measurements which have also been made on the Ti/KCl0{sub}4 mixture. These physical property measurements show that 1) below 300 degrees C no reaction occurs and 2) just above 300 degrees C an exothermic reaction occurs corresponding to the reaction of free Ti with atmospheric oxygen.
Date: September 1, 1979
Creator: Wittberg, T. N.; Moddeman, W. E.; Collins, L. W. & Wang, P. S.
Partner: UNT Libraries Government Documents Department

Towards Long-Term Corrosion Resistance in FE Service Environments

Description: The push for carbon capture and sequestration for fossil fuel energy production has materials performance challenges in terms of high temperature oxidation and corrosion resistance. Such challenges will be illustrated with examples from several current technologies that are close to being realized. These include cases where existing technologies are being modified—for example fireside corrosion resulting from increased corrosivity of flue gas in coal boilers refit for oxy-fuel combustion, or steam corrosion resulting from increased temperatures in advanced ultra supercritical steam boilers. New technology concepts also push the high temperature corrosion and oxidation limits—for example the effects of multiple oxidants during the use of high CO2 and water flue gas used as turbine working fluids.
Date: October 1, 2010
Creator: Holcomb, G. R. & Wang, P.
Partner: UNT Libraries Government Documents Department

Cast Alloys for Advanced Ultra Supercritical Steam Turbines

Description: Develop advanced coal-based power systems capable of 45–50 % efficiency at <$1,000/kW (in 2002 dollars). Develop technologies for capture and sequestration of CO2 that result in: • <10% increase in the cost of electricity in an IGCC-based plant • <35% increase in the cost of electricity for pulverized coal boilers Demonstrate coal-based energy plants that offer near-zero emissions (including CO2) with multiproduct production
Date: October 1, 2010
Creator: Holcomb, G. R. & Wang, P.
Partner: UNT Libraries Government Documents Department

X-ray Photoelectron Spectroscopy study of the compatibility of the explosive PETN with candidate plastic bonding materials

Description: The compatibility of the explosive PETN with two plastic bonding materials, ethyl cellulose and a halogenated vinyl polymer (FPC 461), was determined by X-ray Photoelectron Spectroscopy (XPS). Both were found to coat the PETN crystals, and no change in chemical composition was found in the PETN or the plastic due to either the process or their mutual presence. 3 refs., 1 fig., 1 tab.
Date: January 1, 1985
Creator: Vannet, M.D.; Wang, P.S.; Moddeman, W.E. & Bowling, W.C.
Partner: UNT Libraries Government Documents Department

Surface studies of plastic-bonded PETN and RDX by X-Ray Photoelectron Spectroscopy (XPS) and Ion-Scattering Spectroscopy (ISS)

Description: Surface structures of plastic bonded PETN and RDX were studied by high resolution X-Ray Photoelectron Spectroscopy (XPS) and Ion Scattering Spectroscopy (ISS). The coating material is a copolymer of vinyl chloride and chlorotrifluoroethylene. Specimens with 6 wt % of the coating on RDX and 4 wt % on PETN were used in these studies. High resolution elemented XPS spectra of F 1s, N 1s, C 1s, and Cl 2p indicate that the surface of coated RDX (PBX-9407) is covered and the coating film is thicker than 100A; the results with coated PETN (LX-16) show the surface layer to be thinner than 100A. /sup 3/He/sup +/ ISS data on LX-16 suggest that the coating on PETN is not uniform and is, in fact, absent in some regions.
Date: January 1, 1981
Creator: Wang, P.S.; Moddeman, W.E.; Haws, L.D.; Wittberg, T.N. & Peters, J.A.
Partner: UNT Libraries Government Documents Department

NMR of small platinum particles

Description: /sup 195/Pt NMR lineshapes as well as relaxation data are presented in three different samples of platinum metal particles (46%, 26%, and 15% dispersion) supported on alumina. The electronic properties of these particles are very much different from that of bulk Pt metal. A prominent peak in the lineshape has been identified as a surface resonance which arises from Pt nuclei on the surface of the Pt particles. We find that these surface Pt atoms are non-metallic when coated with adsorbed molecules.
Date: January 1, 1980
Creator: Stokes, H. T.; Rhodes, H. E.; Wang, P. K; Slichter, C. P. & Sinfelt, J. H.
Partner: UNT Libraries Government Documents Department

Overview of surface studies on high energy materials at Mound

Description: Since 1975 Mound has been examining the surface structure of high energy materials and the interaction of these materials with various metal containers. The high energy materials that have been studied include: the pyrotechnic TiH/sub x//KClO/sub 4/, the Al/Cu/sub 2/O machinable thermite, the PETN, HMX and RDX explosives, and two plastic bonded explosives (PBX). Aluminum and alloys of Fe, Ni and Cr have been used as the containment materials. Two aims in this research are: (1) the elucidation of the mechanism of pyrotechnic ignition and (2) the compatibility of high energy materials with their surroundings. New information has been generated by coupling Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) with thermal data. In particular, AES and XPS studies on the pyrotechnic materials and on thermites have shown the mechanism of ignition to be nearly independent of the type of oxidizer present but directly related to surface chemistry of the fuels. In studies on the two PBX's, PBX-9407 and LX-16, it was concluded that the Exon coating on 9407 was complete and greater than or equal to 100A; whereas in LX-16, the coating was < 100A or even incomplete. AES and scanning Auger have been used to characterize the surface composition and oxide thickness for an iron-nickel alloy and showed the thicker oxides to have the least propensity for atmospheric hydrocarbon adsorption. Data are presented and illustrations made which highlight this new approach to studying ignition and compatibility of high energy materials. Finally, the salient features of the X-SAM-800 purchased by Mound are discussed in light of future studies on high energy materials.
Date: January 1, 1980
Creator: Moddeman, W.E.; Collins, L.W.; Wang, P.S.; Haws, L.D. & Wittberg, T.N.
Partner: UNT Libraries Government Documents Department

Hydraulic and hydrologic evaluation of PAR Pond Dam. Technical evaluation report

Description: The PAR Pond Dam at Savannah River Plant was constructed in 1958--1959. Seepage, depressions, boils and spring flow were observed in varying locations on the dam in the last few years. Comprehensive geotechnical and hydraulic investigations pertaining to the effects of the above observations on the abilities of the dam to withstand future floods were made in 1991 and early 1993 where dam capacity to survive flooding and seismic events were evaluated. Brookhaven National Laboratory (BNL) was asked by the Department of Energy (EH) to carry out an independent review of the PAR Pond Dam response to future flooding and seismic events. This report addresses the studies made to evaluate the capacity of the dam to survive floods. A companion report will summarize the evaluations performed to assess the seismic capacity of the dam.
Date: October 1, 1993
Creator: Reich, M.; Wang, P. C.; Khanbilvardi, R. & Bezler, P.
Partner: UNT Libraries Government Documents Department

Validation of a 3-D, Thermo-Mechanically Coupled Model for Multi-Pass Rolling in a Reversing Mill

Description: A three dimensional numerical model simulating multi-pass, hot rolling on a reversing mill has been developed to analyze deformation patterns and shape changes of a rolled ingot. Validation simulations through 15 passes with an 86% reduction have been performed using the thermo-mechanically coupled model to track the evolution of the deformed ingot geometry. The heat transfer coefficient for thermal conduction between the rolls and slab has been estimated in accordance with experimental data, and heat transfer to the air and coolant outside of the roll bite is included. A hyperbolic sine model using the Zener-Hollomon parameter is used to capture the temperature and strain rate dependence of the aluminum alloy. A Coulomb friction model with a flow strength dependent maximum limit on the interfacial shear stress was employed between the rolls and ingot. Results of validation simulations and comparisons with experiments focusing on the ingot shape evolution are discussed.
Date: January 30, 2004
Creator: Rhee, M; Wang, P; Li, M & Becker, R
Partner: UNT Libraries Government Documents Department

Safety consequences of local initiating events in an LMFBR

Description: The potential for fuel-failure propagation in an LMFBR at or near normal conditions is examined. Results are presented to support the conclusion that although individual fuel-pin failure may occur, rapid failure-propagation spreading among a large number of fuel pins in a subassembly is unlikely in an operating LMFBR. This conclusion is supported by operating experience, mechanistic analyses of failure-propagation phenomena, and experiments. In addition, some of the consequences of continued operation with defected fuel are considered.
Date: December 1, 1975
Creator: Crawford, R. M.; Marr, W. W.; Padilla, A. Jr. & Wang, P. Y.
Partner: UNT Libraries Government Documents Department

Phase Behavior of Aqueous NA-K-MG-CA-CI-NO3 Mixtures: Isopiestic Measurements and Thermodynamic Modeling

Description: A comprehensive model has been established for calculating thermodynamic properties of multicomponent aqueous systems containing the Na{sup +}, K{sup +}, Mg{sup 2+}, Ca{sup 2+}, Cl{sup -}, and NO{sub 3}{sup -} ions. The thermodynamic framework is based on a previously developed model for mixed-solvent electrolyte solutions. The framework has been designed to reproduce the properties of salt solutions at temperatures ranging from the freezing point to 300 C and concentrations ranging from infinite dilution to the fused salt limit. The model has been parameterized using a combination of an extensive literature database and new isopiestic measurements for thirteen salt mixtures at 140 C. The measurements have been performed using Oak Ridge National Laboratory's (ORNL) previously designed gravimetric isopiestic apparatus, which makes it possible to detect solid phase precipitation. Water activities are reported for mixtures with a fixed ratio of salts as a function of the total apparent salt mole fraction. The isopiestic measurements reported here simultaneously reflect two fundamental properties of the system, i.e., the activity of water as a function of solution concentration and the occurrence of solid-liquid transitions. The thermodynamic model accurately reproduces the new isopiestic data as well as literature data for binary, ternary and higher-order subsystems. Because of its high accuracy in calculating vapor-liquid and solid-liquid equilibria, the model is suitable for studying deliquescence behavior of multicomponent salt systems.
Date: September 14, 2006
Creator: Gruszkiewiez, M.S.; Palmer, D.A.; Springer, R.D.; Wang, P. & Anderko, A.
Partner: UNT Libraries Government Documents Department