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Corrosion and Protection of Steel Piles in a Natural Seawater Environment

Description: From Introduction: "This paper describes some results of the first eight years of a fifteen year program in which a variety of coating and catholic protection systems are evaluated on their ability to protect steel piles in offshore conditions at Dam Neck, Virginia. It includes a description of the methods used in the evaluation and the results found on these systems."
Date: June 1977
Creator: Escalante, E.; Iverson, W. P.; Gerhold, W. F.; Sanderson, B. T. & Alumbaugh
Partner: UNT Libraries Government Documents Department

Electroplated Metals on Uranium

Description: The following report follows the studies of electroplating on uranium and concurrent metallurgical clodding.
Date: May 7, 1954
Creator: Beach, John G.; Schickner, W. C.; Konecny, C. R. & Faust, Charles L.
Partner: UNT Libraries Government Documents Department

SOLID LUBRICANT COATINGS

Description: Quantitative data on some of the variables affecting the performance of solid dry-film lubricants are presented. Included is a discussion of the test background, theory, methods used, sample pre-test treatment, and variables tested. (J.R.D.)
Date: April 1, 1958
Creator: Berry, L M
Partner: UNT Libraries Government Documents Department

Particle Velocity and Deposition Efficiency in the Cold Spray Process

Description: Copper powder was sprayed by the cold-gas dynamic method. In-flight particle velocities were measured with a laser-two-focus system as a function of process parameters such as gas temperature, gas pressure, and powder feed rate. Particle velocities were uniform in a relatively large volume within the plume and agreed with theoretical predictions. The presence of the substrate was found to have no significant effect on particle velocities. Cold-spray deposition efficiencies were measured on aluminum substrates as a function of particle velocity and incident angle of the plume. Deposition efficiencies of up to 95% were achieved. The critical velocity for deposition was determined to be about 640 meters per second. This work investigates both the in-flight characteristics of copper particles in a supersonic cold-spray plume and the build-up of the subsequent coating on aluminum substrates. Velocities were found to be relatively constant within a large volume of the plume. Particle counts dropped off sharply away from the central axis. The presence of a substrate was found to have no effect on the velocity of the particles. A substantial mass-loading effect on the particle velocity was observed; particle velocities begin to drop as the mass ratio of powder to gas flow rates exceeds 3%. The measured variation of velocity with gas pressure and pre-heat temperature was in fairly good agreement with theoretical predictions. Helium may be used as the driving gas instead of air in order to achieve higher particle velocities for a given temperature and pressure. Coating deposition efficiencies were found to increase with particle velocity and decrease with gun- substrate angle. There did not appear to be any dependence of the deposition efficiency on coating thickness. A critical velocity for deposition of about 640 mk appears to fit the data well. The cold-spray technique shows promise as a method for the ...
Date: November 12, 1998
Creator: Dykhuizen, R.C.; Gilmore, D.L.; Neiser, R.A.; Roemer, T.J. & Smith, M.F.
Partner: UNT Libraries Government Documents Department

Development of a Novel Grease Resistant Functional Coatings for Paper-based Packaging and Assessment of Application by Flexographic Press

Description: Recent commercial developments have created a need for alternative materials and methods for imparting oil/grease resistance to paper and/or paperboard used in packaging. The performance of a novel grease resistant functional coating comprised of polyvinyl alcohol (PVA), sodium tetraborate pentahydrate (borate) and acetonedicarboxylic acid (ACDA) and the application of said coating by means of flexographic press is presented herein. Application criteria is developed, testing procedures described, and performance assessment of the developed coating materials are made. SEM images along with contact angle data suggest that coating performance is probably attributable to decreased mean pore size in conjunction with a slightly increased surface contact angle facilitated by crosslinking of PVA molecules by both borate ions and ACDA.
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Date: August 2004
Creator: Brown, Robert W.
Partner: UNT Libraries

Effects of Resin Coating Methods and Other Variables on Physical Properties of Glass-Fabric Reinforced Polyesters

Description: Memorandum presenting the effects of resin coating methods on some physical properties of laminates prepared with glass fabric, Fiberglas 181, and bonded with two commercial polyester resins. The resins used were Laminac 4126 and Selectron 5003. The resin coating methods used were roller coating, application of a dilute solution of resin, resin immersion, application of monomeric styrene, and vacuum impregnation.
Date: August 23, 1954
Creator: Axilrod, B. M.; Wier, J. E. & Mandel, J.
Partner: UNT Libraries Government Documents Department

Processing, Structure and Tribological Property Relations of Ternary Zn-Ti-O and Quaternary Zn-Ti-Zr-O Nanocrystalline Coatings

Description: Conventional liquid lubricants are faced with limitations under extreme cyclic operating conditions, such as in applications that require lubrication when changing from atmospheric pressure to ultrahigh vacuum and ambient air to dry nitrogen (e.g., satellite components), and room to elevated (>500°C) temperatures (e.g., aerospace bearings). Alternatively, solid lubricant coatings can be used in conditions where synthetic liquid lubricants and greases are not applicable; however, individual solid lubricant phases usually perform best only for a limited range of operating conditions. Therefore, solid lubricants that can adequately perform over a wider range of environmental conditions are needed, especially during thermal cycling with temperatures exceeding 500°C. One potential material class investigated in this dissertation is lubricious oxides, because unlike other solid lubricant coatings they are typically thermodynamically stable in air and at elevated temperatures. While past studies have been focused on binary metal oxide coatings, such as ZnO, there have been very few ternary oxide and no reported quaternary oxide investigations. The premise behind the addition of the third and fourth refractory metals Ti and Zr is to increase the number of hard and wear resistant phases while maintaining solid lubrication with ZnO. Therefore, the major focus of this dissertation is to investigate the processing-structure-tribological property relations of composite ZnO, TiO2 and ZrO2 phases that form ternary (ZnTi)xOy and quaternary (ZnTiZr)xOy nanocrystalline coatings. The coatings were processed by atomic layer deposition (ALD) using a selective variation of ALD parameters. The growth structure and chemical composition of as-deposited and ex situ annealed ternary and quaternary oxide coatings were studied by combined x-ray diffraction/focused ion beam microscopy/cross-sectional transmission electron microscopy, and x-ray photoelectron spectroscopy/Auger electron spectroscopy, respectively. It was determined that the structure varied from purely nanocrystalline (ternary oxides) to composite amorphous/nanocrystalline (quaternary oxides) depending on ALD parameters and annealing temperatures. In particular, the ZnTiO3 ...
Date: August 2014
Creator: Ageh, Victor
Partner: UNT Libraries

Nondestructive Measurements of Aluminum and Nickel Layers on Uranium

Description: From introduction: "This report covers the development of nondestructive techniques for measuring quantitatively: (1) thickness of electrodeposited-nickel diffusion barriers, and (2) thickness of aluminum cladding on flat-plate fuel elements."
Date: June 12, 1954
Creator: Glaze, E. W.; Rhoten, M. L.; Kulp, B. A.; Cooley, K. D. & Wenk, S. A.
Partner: UNT Libraries Government Documents Department

The effects of the Hartman cavity on the performance of the USGA nozzle used for aluminum spray forming. [Quarterly report, July-- September 1996]

Description: This paper addresses the effects of the Hartman cavity on performance of the USGA (Ultrasonic Gas Atomizer) used for Al spray forming. Numerical simulations of the gas flow field were done in order to establish effects of the cavity on flow development both inside and outside the air nozzles. PDPA measurements were made of gas velocity and turbulence intensity, droplet mean and fluctuating velocity, and droplet size across planes at various distances downstream. High speed imaging is used in the flow region near the orifice exit where recirculation zones are generated and there is concern about metal droplet deposition on atomizer surfaces. Shadowgraphy show presence of shock waves and cells in the emerging gas jets. It was found that the Hartman cavity has little effect on droplet sizes generated; also little effect on spray development. The rectangular slit orifices for the 2 gas jets and the liquid jet generate a spray, after impingement, which is somewhat rectangular in cross section. As the spray develops downstream, it changes shape under influence of entrainment from the gas surrounding the spray. After a distance of 254 mm from nozzle exit, width and breadth of the jet are equal but significant shape change occur further downstream. Gaussian velocity distributions result in liquid flux distributions and metal deposits with Gaussian shapes instead of deposits with uniform thickness.
Date: December 31, 1996
Creator: Mansour, A.; Chigier, N.; Shih, T.I.P. & Kozarek, R.L.
Partner: UNT Libraries Government Documents Department

Vacuum deposited polymer films: Past, present, and future applications

Description: Two extremely high rate processes have been developed for the vacuum deposition of polymer thin films. Dubbed the PML (for Polymer Multi-Layer) and LML (for Liquid Multi-Layer) processes, the PML technique was originally developed for the manufacture of polymer/aluminum surface mount capacitors while the LML method arose from a need to fabricate lithium polymer batteries. These processes have since been found to be compatible with most other vacuum deposition techniques in, integrated, in-line coating processes. Battelle has developed an extensive program, and a great deal of hardware, to pursue a wide variety of PML and LML applications which integrate these two process technologies with other, conventional, vacuum deposition methods. The historical development of the technologies is reviewed and the Battelle PML/LML facilities are described. Current Battelle work involving solar thermal control films, PML QWOTs, and polymer/metal high reflectors are also discussed. Battelle PML work that is just starting, involving non-linear optical materials/devices, lithium polymer battery fabrication, electrochromic devices, and polymer/oxide multilayers, is discussed as well.
Date: November 1, 1994
Creator: Affinito, J.; Martin, P.; Gross, M. & Bennett, W.
Partner: UNT Libraries Government Documents Department

METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES

Description: First quarter activities were limited to initial project discussions, laboratory preparation, and some initial coupon preparation. Technical discussion were held with the subcontractors to clearly define their roll in the project. Detailed preparation of the pressure casting lab were started. Initial test coupons were sprayed and provided to Oak Ridge National Lab for infrared lamp fusion trials.
Date: July 1, 2001
Creator: Kiser, Matthew T.
Partner: UNT Libraries Government Documents Department

Impact of Hight Velocity Cold Spray Particles

Description: This paper presents experimental data and an computational model of the cold spray solid particle impact process. Copper particles impacting onto a polished stainless steel substrate are examined. The high velocity impact causes significant plastic deformation of both the particle and the sub- strate, but no melting is observed. The plastic deformation exposes clean surfaces that, under the high impact pressures, result in significant bond strengths between the particle and substrate. Experimental measurements of the splat and crater sizes compare well with the numerical calculations. It is shown that the crater depth is significant and increases with impact velocity. However, the splat diameter is much less sensitive to the impact velocity. It is also shown that the geometric lengths of the splat and crater scale linearly with the diameter of the impacting particle. It is hoped that the results presented will allow better understanding of the bonding process during cold spray.
Date: December 1, 1998
Creator: Dykhuizen, R.C.; Gilmore, D.L.; Jiang, X.; Neiser, R.A.; Sampath, S. & Smith, M.F.
Partner: UNT Libraries Government Documents Department

Final Scientific/Technical Report "Arc Tube Coating System for Color Consistency"

Description: DOE has enabled the use of coating materials using low cost application methods on light sources to positively affect the output of those sources. The coatings and light source combinations have shown increased lumen output of LED fixtures (1.5%-2.0%), LED arrays (1.4%) and LED powered remote phosphor systems – Philips L-Prize lamp (0.9%). We have also demonstrated lifetime enhancements (3000 hrs vs 8000 hrs) and shifting to higher CRI (51 to 65) in metal halide high intensity discharge lamps with metal oxide coatings. The coatings on LEDs and LED products are significant as the market is moving increasingly more towards LED technology. Enhancements in LED performance are demonstrated in this work through the use of available materials and low cost application processes. EFOI used low refractive index fluoropolymers and low cost dipping processes for application of the material to surfaces related to light transmission of LEDs and LED products. Materials included Teflon AF, an amorphous fluorinated polymer and fluorinated acrylic monomers. The DOE SSL Roadmap sets goals for LED performance moving into the future. EFOI’s coating technology is a means to shift the performance curve for LEDs. This is not limited to one type of LED, but is relevant across LED technologies. The metal halide work included the use of sol-gel solutions resulting in silicon dioxide and titanium dioxide coatings on the quartz substrates of the metal halide arc tubes. The coatings were applied using low cost dipping processes.
Date: March 21, 2013
Creator: Buelow, Roger; Jenson, Chris & Kazenski, Keith
Partner: UNT Libraries Government Documents Department

Preliminary evaluation of PS300: A new self-lubricating high temperature composite coating for use to 800{degrees}C

Description: This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800{degrees}C. PS300 is a metal bonded chrome oxide coating with silver and BaF{sub 2}/CaF{sub 2} eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating; which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650{degrees}C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.
Date: December 31, 1996
Creator: DellaCorte, C. & Edmonds, B.J.
Partner: UNT Libraries Government Documents Department

Vapor deposition of copper on stainless steel 304L

Description: Y-12 Plant is seeking to minimize the generation of hazardous wastes in its operations. The standard procedure for electroplating a thin layer of copper on type 304L stainless steel requires several aqueous pretreatment steps which generate Resource Conservation and Recovery Act (RCRA) hazardous wastes. We have evaluated a more environmentally acceptable procedure. Copper was vacuum deposited onto 304L coupons under differing deposition conditions and properties of coatings produced, including microstructure and adhesive strength, were examined. Results indicated that a noncolumnar, fine grain copper coating with high adhesion can be produced using this environmentally more acceptable approach.
Date: August 17, 1993
Creator: Vasofsky, R. W.
Partner: UNT Libraries Government Documents Department