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Study of Chromium-Frit-Type Coatings for High-Temperature Protection of Molybdenum

Description: "The achievement of more compact and efficient power plants for aircraft is dependent, among other factors, on the perfection of heat-resisting materials that are superior to those in current use. Molybdenum is one of the high-melting metals (melting point, 4750 F). It is fairly abundant and also can be worked into many of the shapes required in modern power plants. To permit its widespread use at elevated temperatures, however, some means must first be found to prevent its rapid oxidation" (p. 1).
Date: July 1951
Creator: Moore, D. G.; Bolz, L. H.; Pitts, J. W. & Harrison, W. N.
Partner: UNT Libraries Government Documents Department
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The Galvanic Corrosion Theory for Adherence of Porcelain-Enamel Ground Coats to Steel

Description: Note presenting an investigation of the galvanic corrosion theory of adherence between ground-coat porcelain enamels and steel as part of a broad study of the bonding mechanism between ceramics and metals. The theory is based on the mechanical anchoring of the enamel into the pits formed by the galvanic attack of the enamel on the steel surface.
Date: June 1953
Creator: Moore, D. G.; Pitts, J. W.; Richmond, J. C. & Harrison, W. N.
Partner: UNT Libraries Government Documents Department
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Effect of Oxygen Content of Furnace Atmosphere on Adherence of Vitreous Coatings to Iron

Description: Note presenting a series of vitreous coatings of the same basic composition, but with cobalt-oxide contents varying from 0 to 6.4 percent by weight, which was fired on ingot iron in atmospheres consisting of various oxygen-nitrogen mixtures. Results of the investigation showed that a decrease in the amount of oxygen in the firing atmosphere necessitated an increase in the amount of cobalt oxide in the enamel if optimum adherence was to be secured.
Date: May 1955
Creator: Eubanks, A. G. & Moore, D. G.
Partner: UNT Libraries Government Documents Department
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Carbide Coatings on Graphite

Description: From abstract: "A Method has been developed for the uniform coating of graphite tubes with carbides of niobium, tantalum, and zirconium by thermal composition of their respective halide vapors."
Date: 1957
Creator: Blocher, John M., Jr.; Ish, Carl J.; Leiter, Don P.; Plock, Layne F. & Campbell, Ivor E.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of Air-Cooled Turbine Blades in Turbojet Engine 13: Endurance Evaluation of Several Protective Coatings Applied to Turbine Blades of Nonstrategic Steels

Description: Memorandum presenting an investigation of the durabilities of several protective coatings applied to air-cooled gas turbine rotor blades of nonstrategic steels in modified turbojet engines. Four types of coatings (ceramic, nickel, Nicrobraz, and aluminized) were applied to a total of 20 blades.
Date: July 16, 1953
Creator: Bartoo, Edward R. & Clure, John L.
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin IV: The Use of Protective Coatings

Description: Although the corrosion resistance of sheet duralumin can be greatly improved by suitable heat treatment, protection of the surface is still necessary if long life under varied service conditions is to be insured. The coatings used for this purpose may be grouped into three classes: the varnish type of coating, the oxide type produced by a chemical treatment of the surface, and metallic coatings, of which aluminum appears to be the most promising. Since the necessary weather exposure tests are not complete, some of the conclusions regarding the value of various surface coatings are necessarily tentative.
Date: April 1928
Creator: Rawdon, Henry S.
Partner: UNT Libraries Government Documents Department
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Cleaning and Decontamination Using Strippable and Protective Coatings at the Idaho National Engineering and Environmental Laboratory

Description: The Idaho National Engineering and Environmental Laboratory (INEEL) Radioactive Liquid Waste Reduction (RLWR) group is conducting a testing and evaluation program on strippable and protective coatings. The purpose of the program is to determine how and where these coatings can be used to aid in the minimization of liquid waste generation. These coatings have become more important in daily operations because of the increased concern of secondary liquid waste generation at the INEEL. Several different strippable and protective coatings were investigated by the RLWR group, including Pentek 604, Bartlett (TLC), and ALARA 1146. During the tests quantitative data was determined, such as effectiveness at reducing contamination levels, or costs, as well as some qualitative data on issues like ease of application or removal. PENTEK 604 and Bartlett TLC are seen as superior products with slightly different uses.
Date: March 1, 1999
Creator: Tripp, J.; Archibald, K.; Lauerhass, L.; Argyle, M. & Demmer, R.
Partner: UNT Libraries Government Documents Department
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Preliminary report on development of coating for alloy case

Description: Coatings examined were selected industrial finishes reported to have good resistance to corrosion and included epoxy resins reinforced with fiberglass. For screening purposes,this preliminary work was done on commercial sheet Mg to which had been applied a dichromate finish. The coatings were tested for impact resistance, corrosion resistance, abrasion resistance, and thermal shock resistance. Conclusions for further work are outlined.
Date: July 27, 1956
Creator: Archibald, P.B.
Partner: UNT Libraries Government Documents Department
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Abstracted model for ceramic coating

Description: Engineers are exploring several mechanisms to delay corrosive attack of the CAM (corrosion allowance material) by dripping water, including drip shields and ceramic coatings. Ceramic coatings deposited with high-velocity oxyfuels (HVOF� s) have exhibited a porosity of only 2% at a thickness of 0.15 cm. The primary goal of this document is to provide a detailed description of an abstracted process-level model for Total System Performance Assessment (TSPA) that has been developed to account for the inhibition of corrosion by protective ceramic coatings. A second goal was to address as many of the issues raised during a recent peer review as possible (direct reaction of liquid water with carbon steel, stress corrosion cracking of the ceramic coating, bending stresses in coatings of finite thickness, limitations of simple correction factors, etc.). During the periods of dry oxidation (T 2 100°C) and humid-air corrosion (T I 100°C & RH < SO%), it is assumed that the growth rate of oxide on the surface is diminished in proportion to the surface covered by solid ceramic. The mass transfer impedance imposed by a ceramic coating with gas-filled pores is assumed to be negligible. During the period of aqueous phase corrosion (T I 100°C & RH > 80%), it is assumed that the overall mass transfer resistance governing the corrosion rate is due to the combined resistance of ceramic coating & interfacial corrosion products. Two porosity models (simple cylinder & cylinder-sphere chain) are considered in estimation of the mass transfer resistance of the ceramic coating. It is evident that substantial impedance to 02 transport is encountered if pores are filled with liquid water. It may be possible to use a sealant to eliminate porosity. Spallation (rupture) of the ceramic coating is assumed to occur if the stress introduced by the expanding corrosion products at the …
Date: November 14, 1998
Creator: Farmer, J C & Stockman, C
Partner: UNT Libraries Government Documents Department
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A correlation between EIS and salt spray proof tests for the corrosion resistance of conversion coated aluminum alloys

Description: In this study, 33 different conversion coatings were applied to 5 different Al alloy substrates. Salt spray exposure testing and EIS (electrochemical impedance spectroscopy) were conducted for comparison. A relation was developed.
Date: September 1, 1996
Creator: Buchheit, R. G.; Martinez, M. A.; Cunningham, M.; Jensen, H. & Kendig, M. W.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF PROTECTIVE COATINGS FOR SINGLE CRYSTAL TURBINE BLADES

Description: Turbine blades in coal derived syngas systems are subject to oxidation and corrosion due to high steam temperature and pressure. Thermal barrier coatings (TBCs) are developed to address these problems. The emphasis is on prime-reliant design and a better coating architecture, having high temperature and corrosion resistance properties for turbine blades. In Phase I, UES Inc. proposed to develop, characterize and optimize a prime reliant TBC system, having smooth and defect-free NiCoCrAlY bond layer and a defect free oxide sublayer, using a filtered arc technology. Phase I work demonstrated the deposition of highly dense, smooth and defect free NiCoCrAlY bond coat on a single crystal CMSX-4 substrate and the deposition of alpha-alumina and yttrium aluminum garnet (YAG) sublayer on top of the bond coat. Isothermal and cyclic oxidation test and pre- and post-characterization of these layers, in Phase I work, (with and without top TBC layer of commercial EB PVD YSZ) revealed significant performance enhancement.
Date: December 4, 2006
Creator: Rai, Amarendra K.
Partner: UNT Libraries Government Documents Department
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The response of hydrotalcite coated aluminum to sealing with transition metal salt solutions

Description: Objective was to determine if the protective coating could be enhanced by filling intercrystalline spaces or by reinforcing the coating at intermetallic particles by exposure to aqueous transition metal salt solutions. Two oxy-anion analogs to chromate were used: permanganate and molybdate. Ce(III) (as Ce(NO{sub 3}){sub 3}) was also studied. (Al alloys 2024-T3 and 6061-T6 were used as substrates.) Results are summarized. 4 figs, 1 tab, 3 refs.
Date: 1994
Creator: Buchheit, R. G. & Martinez, M. A.
Partner: UNT Libraries Government Documents Department
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Application of thick film and bulk coating technology to the Subterrene program

Description: From conference on structure-property relationships in thick film and bulk coatings; San Francisco, California, USA (28 Jan The Subterrene is a rock- melting earth-penetration system representing a significant advancement in excavation technology. Temperatures of 1700-2000 deg K are involved, and heated refractorymetal or alloy probes are used. Corrosion problems are severe on the exterior surfaces of the refractory metals used; bulk coatings having the required properties would be extremely desirable provided they could be deposited upon a substrate as a tenacious coating. Within the Subterrene, pyrographite radiant heaters are operating at temperatures to 2450 deg K. Graphite receptors added to improve the radiant heat transfer react with the Mo and W penetrator bodies to form carbides. A 30 mu m-thick CVD film of TaC may be applied to inhibit this reaction. The techniques of applying these fllms, their nature, and the results of their application, are discussed. The environment of an operating penetrator is described, and the requirements and properties of exterior coatings are outlined. (auth)
Date: January 1, 1974
Creator: Stark, W. A., Jr.; Wallace, T. C.; Witteman, W.; Krupka, M. C.; David, W. R. & Radosevich, C.
Partner: UNT Libraries Government Documents Department
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Sodium compatibility studies of low friction carbide coatings for reactor application

Description: Design requirements for low friction materials in FFTF have led to an experimental sodium compatibility program, the objective of which is to select and qualify a low friction coating for the fuel assembly duct load pad. Results are given for chromium carbide and titanium carbide-based coatings on stainless steel exposed to 1160 deg F sodium for several thousand hours. A chromium carbide coating (with a nichrome binder) having an average corrosion rate of approximately 0.25 mpy exhibits optimum sodium compatibility behavior of the materials examined. Both plasma-sprayed chromium carbide and titanium carbide based coatings were found to be unstable when exposed to sodium. (auth)
Date: September 1, 1973
Creator: Whitlow, G. A.; Miller, R. L.; Schrock, S. L. & Wu, P. C. S.
Partner: UNT Libraries Government Documents Department
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Advanced Thermal Barrier Coating System Development

Description: The objectives of the program are to provide an improved Thermal Barrier Coating (TBC) system with increased temperature capability and improved reliability relative to current state of the art TBC systems. The development of such a coating system is essential to the ATS engine meeting its objectives. The base program consists of three phases: Phase I: Program Planning - Complete; Phase II: Development; and Phase III: Selected Specimen - Bench Test Work is being performed in Phase II and III of the program.
Date: March 31, 1999
Partner: UNT Libraries Government Documents Department
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Ceramic Coatings for Components Exposed to Coal-Gas Environments : a Review

Description: The corrosive and erosive environments at high temperatures and pressures in coal gasifiers impose severe requirements on the alloys of fabrication. A concise review of the application of ceramic coatings to resist coal-gas environments has been conducted. The purpose of this review is to explore suitable ceramic or cermet materials that may resist or retard the degradation of metal components and to summarize the state of the art of various methods of producing such coatings.
Date: December 1976
Creator: Swaroop, Robert
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT AND MANUFACTURE OF COST EFFECTIVE COMPOSITE DRILL PIPE

Description: This technical report presents the engineering research and data accomplishments that have transpired to date in support of the development of Cost Effective Composite Drill Pipe (CDP). The report discusses and illustrates all progress in the first two years of this NETL/DOE supported program. The following have been accomplished and are reported in detail herein: (1) Specifications for both 5 5/16 inch and 3 3/8 inch composite drill pipe have been finalized. (2) All basic laboratory testing has been completed and has provide sufficient data for the selection of materials for the composite tubing, adhesives, and abrasion coatings. (3) Successful demonstration of composite/metal joint interfacial connection. (4) Upgrade of facilities to provide a functional pilot plant manufacturing facility. (5) Arrangements to have the 3 3/8 inch CDP used in a drilling operation early in C.Y. 2002. (6) Arrangements to have the 5 5/16 inch CDP marketed and produced by a major drill pipe manufacturer.
Date: October 30, 2001
Creator: Leslie, James C.; Jean, Jeffrey R.; Neubert, Hans & Truong, Lee
Partner: UNT Libraries Government Documents Department
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Evolution of microstructure and mechanical properties in laser induced reaction coating of Al{sub 2}O{sub 3} on SiC/Al{sub 2}O{sub 3} composite

Description: Protection of a SiC(p)/Al2O3 composite (SiC particulate-reinforced Al{sub 2}O{sub 3}-matrix) at high temperature from deleterious reactions occurring within and with the surrounding environment is required for high temperature applications. Development of a continuous Al2O3 coating on SiC(p)/Al2O3 ceramic composite for such protection is achieved using the laser assisted in-situ reaction technique. The as-deposited alumina coating was analyzed using optical microscopy and XRD. The coated samples were also evaluated for mechanical properties using 3-point bend tests.
Date: December 31, 1996
Creator: Dahotre, N. B.; Xiao, C.; Boss, W.; McCay, M. H. & McCay, T. D.
Partner: UNT Libraries Government Documents Department
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Transmission electron microscopy of undermined passive films on stainless steel

Description: A study has been made of the passive film remaining over pits on stainless steel using a high resolution transmission electron microscope. Type 305 stainless steel was passivated in a borate buffer solution and pitted in ferric chloride. Passive films formed at 0.2 V relative to a saturated calomel electrode were found to be amorphous. Films formed at higher potentials showed only broad diffraction rings. The passive film was found to cover a remnant lacy structure formed over pits passivated at 0.8 V. The metallic strands of the lace were roughly hemitubular in shape with the curved surface facing the center of the pit.
Date: June 1, 1999
Creator: Isaacs, H. S.; Zhu, Y.; Sabatini, R. L. & Ryan, M. P.
Partner: UNT Libraries Government Documents Department
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