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The objectives of this program were to study the effects of aluminum and zinc metal substrates with a passive overcoat on the corrosion fatigue life of HY 130 in a marine environment and to develop a shipboard repair process for hydrofoil strut and foil external coatings. Conclusions were reached about the effectiveness of the active metal substrates in protecting HY 130. A repair material and procedure were recommended. (Author), HYSTU Plan Number 303.

The operation of an electro-optic image modulator and storage device for use in real-time optical processing systems is described. Major emphasis was placed in optimizing the device performance by proper selection of design and operating parameters. The Pockels Read-Out Optical Modulator (PROM) is used to provide temporary storage of an image that can be read into the PROM either sequentially from a laser or CRT scanner or in parallel from a transparency. The PROM is constructed from a thin slice of bismuth silicon oxide, a cubic crystal exhibiting the Pockels effect, photoconductivity when illuminated with blue light, and resistivity sufficient to allow up to 2 hours of charge storage. The crystal slice is oriented normal to (100), polished flat, and coated with an insulating layer of parylene. A dichroic layer, reflecting red light but transmitting blue, is sometimes deposited on one side of the crystal before it is coated with parylene. In the operation of the device, an electric field is first stored in the crystal by inducing surface charges at the crystal-parylene interfaces. The stored image can then be read out by incoherent light or by a laser for coherent optical processing.

A study was conducted to investigate the reliability of organic adhesives in hybrid microcircuits. The objectives of this study were twofold: (1) to identify and investigate problem areas that could result from the use of organic adhesives and (2) to develop evaluation tests to quantify the extent to which these problems occur for commercially available adhesives. Efforts were focused on electrically conductive adhesives. Also, a study was made to evaluate selected organic coatings for contamination protection for hybrid microcircuits. The results of these studies are reported. jg p2

This interim report describes the initial phases of the investi-gation to provide ultra-lightweight, low-loss optical fiber communication cables for tactical field army environments. Initial efforts to use low- loss optical waveguides in a cable structure resulted in unacceptable increased in fiber attenuation. These increased losses were attributed to micro-distortions in the low- loss fibers introduced by coatings and/or the cable structure. the program was redirected to seek a solution to this problem which would allow the use of state- of-the-art optical fibers in cable structures. Organic coatings applied by extrusion techniques to the optical fibers are a solution and have permitted cable unit structures without any significant increase in the atten-uation of the individual fibers. An approved cable unit will ultimately be incorporated in a structure designed to provide a rugged cable. (Author-PL)

Edited trans. of Izvestiya (USSR) n252 p3, 26 Oct 73, by Charles T. Ostertag, Jr.

Edited trans. of Trudy II Soveshchaniya po Khimii i Prakticheskomu Primeneniyu Kremniiorganicheskikh Soedinenii, Leningrad, Dec 69. Kremniiorganicheskikh Soedinenii, Leningrad, Dec 69. Kremniiorganicheskie Materialy, n.p., 1971 p268-270, by Louise E. Heenan.

Strippability characteristics of various plasticizers and surfactants in combination with Geon Latex 652 vehicles on plexiglas and client's panels are given. Included are results obtained before and after accelerated weathering. ResultsARE REPORTED ON THE ATTACK OF VARIOUS PLASTICIZERS AND SURFACTANTS ON SPECIMEN Navy finishes. Data are reported on heat resistance and thickening studies of various combinations of ingredients. No success has been achieved in the development of a formula which is strippable from plexiglas or from lacquered panels when applied in thin films and exposed to accelerated weathering. (Author)

The ability of ten candidate fungicides, singly and in combination, to suppress fungal growth on a variety of organic coatings under natural, tropical conditions was investigated. After 1 year of exposure, substantial protection for the susceptible coatings was afforded by copper-8-quinolinate and binary mixtures of p-toluenesulfonamide with copper-8-quinolinate and phenylmercuric phthalate in fairly low concentration. At a higher concentration, p-toluenesulfonamide provided good protection for the susceptible coatings, while its N-ethyl derivative was less effective and its N-cyclohexyl derivative was almost inert. At an intermediate concentration, 2,3-dichloro-1, 4-naphthoquinone and p-chlorophenoxyacetic acid provided effective protection for the susceptible coatings. None of the eight binary mixtures tested showed any evidence of synergism. The results confirm those obtained from earlier exposure programs, which showed that p-toluenesulfonamide is effective at higher concentrations in providing protection against fungal infestations. It was observed, however, that at very low levels this material may act as a growth promoter.

The report covers the evaluation of a material which is ultra thin, has good water displacing properties, and possess corrosion preventive properties, and which is dry-to-the-touch when used on land-based aircraft in dusty areas.

A theoretical discussion of the problem of current distribution along a wire rope cathode is discussed. A curve has been estimated from these considerations which shows the current distribution factor for 1 1/4 inch wire rope for several anode potentials. The conclusions drawn from this study show that it is impossible to protect several thousand feet of bare wire rope from a central anode location, but that many thousand feet of even imperfectly coated wire rope could easily be provided cathodic protection from a central location.

Extensive work was done on jet rinsing and experimental results are presented. Work was started on surface passivation by oxidation and experimental results are reported. Experiments on surface passivation by organic coats were started and results are given. Further work on injection alloying indicated that control over the process is exceedingly difficult. Steps were taken which will make a 100% helium leak test feasible. In addition, the possibility is being explored of baking a thin coat of silicon resin onto welded units to close up microscopic leaks.

The development and investigation of phosphate binder composition for use with reinforced laminated glass fibers at limited elevated temperature applications. The experimental data include some mechanical and electrical properties.

ORGANIC COATINGS ARE BEING STUDIED AS ONE POSSIBLE MEANS OF ACHIEVING TEMPERATURE CONTROL WITHIN SPACE VEHICLES; HOWEVER, THEIR USEFULNESS IN THE SPACE ENVIRONMENT IS LIMITED BY THEIR PHYSICAL AND CHEMICAL STABILITY IN SPACE. It is shown that the optical properties of most organic coatings are changed on exposure to intense UV radiation in high vacuum. Of the reflective pigments studied, those containing zinc sulfide and leafing aluminum are shown to be most stable in this radiation., See also AD0240141.

Various plasticizers and surfactants were tested as potential modifiers of Geon Latex 652, a polyvinyl chloride emulsion. Plasticized Geon Latex 652 films were subjected to aging at elevated temperatures as an accelerated indication of their behavior over prolonged periods at ordinary temperatures. Thickening and pigmentation of plasticized vehicles was studied. Three white strippable coating formulations were prepared based on the results of raw material evaluations. (Author)

Actual problems in the field use of polysulfide, rubber(Thiokol), vinyl copolymers, and vinylidine chloride (Saran) as liners for steel and concrete fuel storage tanks are discussed.

The design and assembly of the radio frequency glow discharge and ultraviolet photolysis equipment for the polymerization of organic monomers on potassium chloride laser windows has been completed. The ultraviolet photolysis chamber has been modified to permit glow discharge cleaning of the potassium chloride prior to the polymeric deposition. Deposition by a combination of glow discharge and ultraviolet photolysis is also possible. Preliminary polymer depositions using the photolytic chamber were conducted. Chemical polishing studies were initiated using n-butyl and isopropyl alcohols and a Syntron Polisher, both with and without polishing powders. Surface removal rates of about 600 A/minute were established., See also ADA003631.

Numerous proprietary and developmental organic coatings were screened for their relative corrosion protection of Mg sheet alloy. Superior primers and systems were more fully evaluated for their mechanical properties as well as corrosion protection. Finish evaluations were conducted on FS-IH Mg alloy. The coatings included vinyls and modified vinyls, alkyd and modified alkyd finishes, acrylic and modified acrylic finishes, HAE refractory coatings, and miscellaneous vehicles. The air-dry vinyl systems offered optimum protection in the systems tested. Developmental data and discussions of Mg corrosion inhibitors and galvanic-cell test methods are included.

The fluidized bed coating process is sometimes referred to as 'powder painting' or simply 'plastic cladding'. Process details, advantages and deficiencies of the process as compared with conventional coating methods, as well as tricks of the trade, are covered. Masking, cold fixturing techniques, patching of the coatings, inspection techniques, machining, and special applications of the coatings are discussed. Use of the process in applying both plastic and metallic coatings reveals an envisioned future application of fluidized bed techniques. (Author)

This document contains summarized information relating to steady-state radiation effects on thermal-control coatings. The radiation includes nuclear, charged particles and ultraviolet. The data will provide useful information to the design engineer responsible for choosing thermal-control coatings in space applications.

To determine factors influencing formation of cracks in the heat-affected zone of arc welded alloy steels. Root cracks (base metal cracks parallel and very close to the fusion zone) occur only when the weld heating and quenching cycle produces a martensitic type structure in the vase metal immediately adjacent to the fusion line. They are observed only when ferritic electrodes with hygroscopic organic type coatings are used. It is demonstrated that root cracks may be eliminated by heating electrodes in an oven immediately before use, presumably driving off absorbed and combined moisture.

The report covers the observations made subsequent to a tour of temporary duty in England, France, Switzerland, Holland, and Germany, in order to obtain as much information as possible in regard to paint, varnish, and lacquer factories and research laboratories in these countries. Emphasis was placed on obtaining information which might be novel and which might lead to improved and less expensive protective and decorative organic coatings. The findings set forth in this report are to be employed in protective coating problems occurring during tests and investigations being conducted at the Engineer Research and Development Laboratories, Fort Belvoir, Virginia.

Research was continued to investigate new and improved high temperature (up to 8oodeg F) resistant coatings capable of withstanding aerodynamic heating of high speed (greater than Mach 3) aircraft and missile systems. Fluorinated ethylene propylene and polychlorotrifluoroethylene coatings have been satisfactorily applied by plasma spraying. Polytetrafluoroethylene and a coating-grade polyarylsulfone resin did not show adequate melt flow to allow film coalescence. A varnish coating of a benzoxazole-imide ordered copolymer has shown outstanding property retention during extended aging at 650deg F. (Author, Modified-PL).

This purchase description covers one type of coated explosive material referred to herein as CXM-1. The material is HMX explosive coated with an uncured resin containing unsaturated polyesters. (Author)

The report describes the development and current status of collapsible self-supporting POL tanks of 1,250-, 2,500-, and 5,000-barrel (approximately 50,000-, 100,000-, and 200,000-gallon) capacity. The tanks are made of an elastomer-coated nylon and are to be used for temporary storage of POL in the field army area. (Author), Supersedes Rept. no. AMC-TIR-33.8.6.4(1), AD-817 128.

Silicone and organic polymeric coatings systems have been sought with improved resistance to thermooxidative degradation in the 650 to 800 deg F air environment. Pigmented metal phosphate coatings have been investigated for utility to 1000 deg F. Silicone resins show the greatest promise for high temperature pigmented coatings on titanium. A semi-gloss white silicone coating retained interesting coating properties in excess of 2000 hr at 650 deg F. A gloss white silicone, although showing shorter utility, possessed superior gloss and extensibility. The organic polymers remain of interest particularly in unpigmented coatings because of their potentially longer retention of coating extensibility and water impermeability. Among the organic coating resins, a polyarylsulfone showed the best retention of coating integrity and adhesion after high temperature exposure. A pigmented casting showed utility for approximately 500 hr at 650 deg F. An unpigmented varnish coating retained interesting properties for about 400 hr but was sensitive to cracking from ultraviolet radiation. Surface treatment of a titanium substrate appears to be essential for obtaining good coating adhesion under thermooxidative and wide thermal cycling conditions. The greatest improvement has been achieved with a nickel-aluminum primer. Among chemical treatments employed, an HF-HC1-H3PO4 etch showed the best adhesion improvement. Pigmented metal phosphate coatings offer no obvious advantages over the silicone coatings on titanium-6A1-4V. (Author-PL).

The objective of this test was to develop and test a method of controlling contaminants in 'D' and 'E' Series Propellant Utilization manometer housings so that contamination of the housings would minimize failures of the Propellant Utilization System. (Author)

A survey was made of the capabilities of the electrophoretic painting process of applying organic coatings. Electrophoretic paints and paint deposition mechanisms, process equipment, and control requirements were investigated and vendor/users surveyed. The electrophoretic painting process can be used in the application of organic coatings. (Author)

The object of this study is to determine the feasibility of making elevated-temperature (700 F) reflective coatings which have high diffuse reflectance from the visible to at least 5 micron in the infrared. More specifically, the objective is to theoretically analyze reflectance as applied to the 0.4 to 10 micron region in a two-phase medium using the Monte Carlo computer technique and the principles of particle light scattering. Also, the theoretical results are to be verified by experimental tests on model samples prepared from candidate materials. The major goal is to select the best candidate pigment materials and optimize particle size and distribution.

For many years the Army has experienced problems in low temperature flexibility, environmental stability and moisture which penetrated needle holes left in coated fabrics resulting from sewing. Several methods to overcome the problem of needle holes were used. These added costs and time delays prompted a new look at the development of an improved coated fabric. A research study was initiated wherein 28 varieties of commercially available coated fabrics, 3 substrates (one glass cloth and two varieties of nylon), 8 tie-coatings and 21 polymer coatings were investigated for the purpose of obtaining an improved coated fabric. As a result of these development and evaluation studies, it was found that a dimethyl sulfoxide treatment on an open mesh nylon substrate which was then coated with polyethylene/vinyl acetate produces an acceptable heat sealable all weather coated fabric. The dimethyl sulfoxide and/or dimethyl formamide pretreated substrate showed an improvement of 20F in low temperature flexibility over an untreated substrate. DuPont's 60-002 urethane (ether) polymer compound applied at Rock Island Arsenal to an open mesh nylon, and Reeves Bros. Inc., Style 15187, urethane (ether) coated on a standard weave dacron substrate exhibited favorable properties in regard to fuel resistance and heat sealability. (Author)

The purpose of this report is to describe the equipment and state-of-the-art of processes used in physical vapor deposition (PVD), the properties and applications of articles coated by PVD, and methods of testing coated products. PVD, which includes the well known 'vacuum metallizing,' is the most frequently used means for depositing coatings from the vapor phase. A major characteristic of PVD is that the coating material is identical with the source material. The processes of PVD may be grouped into three general classes, according to the manner in which the source material is vaporized: (1) those that utilize sublimation or evaporation (this group includes 'vacuum metallizing'), (2) sputtering, and (3) ion plating.

The latest results from a study of the dynamic behavior of rain erosion resistant materials are described. The basic dynamic properties of candidate rain erosion resistant coatings and substrates have been measured and then correlated with rain erosion observations. It is shown that a fatigue type of behavior, already found to be applicable for an acrylic plastic, may also be used to describe the rain erosion resistance of elastomeric coatings such as AFML polyurethane, and the glass fiber reinforced epoxy composite substrates which are frequently used for radome construction. The importance of the 'dynamic recovery rate' of materials, and of stress wave interactions, in understanding the rain erosion phenomenon is described in this report. The applicability of the elastic-plastic, uniaxial stress wave theory for making rain erosion predictions is also discussed. (Author)

This report summarizes the experiences gained in organizing and implementing quality control of non-metallic protective coverings as practiced in the construction of facilities within the metallurgical, chemical, mining, machine construction, light and food processing industries. A DETAILED DESCRIPTION IS OFFERED OF THE METHODS USED IN DETERMINING THE QUALITATIVE INDEXES OF PROTECTIVE COVERINGS. Special attention is directed to defects found in lacquer, rubberized, ceramic and polymer coverings, as well as to the methods used in eliminating them. Consideration is given to problems dealing with the improvements of quality of coverings and in perfecting quality production controls. As a practical manual it is intended for the use of engineer and technician personnel who are involved in the handling and use of protective coverings, as well as for foremen, specialists, and engineers directly involved in this work. It contains 15 tables, 14 references, 4 drawings. (Author-PL), Trans. of Unidentified mono. pub. by Budivelnik Publishing Office, Kiev, 1969 p2-107.

This report discusses the rain erosion resistance of various coatings used as protection on radomes, aerial covers and metallic leading edges. Specialised applications such as the erosion problems connected with air cushion vehicles are also included. Most of the tests were conducted under standard conditions of 500 mile/h in 1 in/h simulated rainfall but some results at lower speeds are listed. The best erosion resistance was obtained with stainless steel, but some polyurethane sheet materials also gave excellent protection, provided that a good adhesive bond to the substrate had been obtained. A form of polyurethane self-adhesive tape gave protection to an intermediate degree and had the added advantages of ease of application and replacement when necessary. (Author)

The report discusses the use of castellated I-beams for structural use., Text in French; attached summary in English.

A pyrolysis-infrared technique for the qualitative 'fingerprint' identification of some low-level surface treatments on glass fibers is described. The infrared spectrum obtained by pyrolysis of the treated surface will be characteristic of the room-temperature-condensable vapors of the major component in the treatment formulation. This method is not applicable for treatments which do not produce room-temperature-condensable pyrolysis products. The simplicity, rapidity, and reproducibility of the procedure will permit the qualitative specification and control of most polymeric film formers and lubricants. However, only a few of the silane treatments used on fiberglass can be identified. (Author)

Two members of the poly-m-carboranesiloxane family were selected for extensive testing to determine their ppotential in high temperature applications between 500 and 900 F. Efforts were concentrated on an insoluble raw gum which lends itself primarily to molding operations; its synthesis was developed into a routine operation. Volatile loss determinations, long term heat-aging studies, compression set tests, shrinkage and electrical property measurements were conducted on variably compounded vulcanizates. Their tensile strength and elongation could be improved by increased filled loading in conjunction with modified molding techniques. End use items such as O-rings and other seals, diaphragms and electrical connector inserts are now undergoing application testing. For coatings and related uses, a soluble viscous liquid form is best suited and can be easily applied on metals or fabrics from aromatic solvents. Curing does not require peroxides and is achieved between 300 and 600 F. (Author), Prepared for presentation at the Spring Meeting of the Division of Rubber Chemistry (93rd), American Chemical Society, Cleveland, Ohio, 23-26 Apr 68.

The development of a portable gauge to demonstrate the use of beta radiation for corrosion detection was the primary goal of this program. The gauge was designed for detecting corrosion occurring at the interface between an aluminum substrate and an overlying organic protective coating. From this development program, appreciable insight was acquired for the development of a prototype gauge of this type. Test samples were fabricated from aluminum corrosion products (Al2O3) and used for calibration purposes. Laboratory data with these samples indicated that corrosion depths could be detected over a dynamic range of from 2 to about 20 mils with the presently designed gauge. Also, it was found that the gauge responded quite well to corrosion and pitting on the underside of thin metals such as aluminum and magnesium aircraft skins (skin thickness no greater than 20 mils for maximum sensitivity). The test results with calibrated surface corrosion samples and results of work concerning corrosion detection on the underside of aircraft skins are discussed. Also, photographs of the test results are given for surface and sub-surface detection. (Author)

Contents: The role of protective shielding in radiation safety systems; Use of sheets with an adhesive layer as protective coating against radioactive contamination; Investigation of organic coating materials for protective coating from radioactive contaminations; The application of epoxy coatings for protection of metallic and concrete surfaces; Meters and dosimeters for study of protection and the protective properties of materials., Edited trans. of mono. Zashchitnye Pokrytiya v Atomnoi Tekhnike. Sbornik Statei, n.p., 1963 p5-10, 93-7, 126-36, 144-7, 260-70.

An epoxide-polyoxypropylene diamine (POPDA-400) cured coating system with improved flexibility, wet adhesion to aluminum substrate, resistance to low (-40F) and high (400F) temperature aging, accelerated weathering and ultra-violet aging over the epoxide-polyamide system was developed for application to Naval aircraft. Polyoxypropylene diamine of molecular weight 490 to 550 (POPDA-400) showed the most promise as a curing agent for the epoxide resins, the cure rate conforming to Contract specifications. Synthesis of POPDA-400 and evaluation of the epoxide-POPDA-400 coating system are described. (Author)

There is no analytical method for measuring the amount of carbon pigment in high-gloss black enamels and lacquers, and no accurate procedure for determining the total pigment content of any coating that contains carbon. The colloidal suspension of extremely small particles of carbon prohibit separation and measurement by filtration or by contrifugation. This report describes a new, simple, rapid quantitative method for measuring total pigment in any solvent-type organic coating including those containing carbon pigments. It is based on agglomeration of suspended particles in a nonaqueous medium, followed by filtration and washing in a special crucible.

Mineral particles suspended in surface seawater in tropical and subtropical regions are composed primarily of carbonates and quartz. The particles, which are in the size range 10-50 microns, can be present in concentrations at least as high as 5 mg per liter. Organic coatings on the mineral grains prevent free interaction between the seawater and the particles; thus they do not act as nuclei for precipitation from supersaturated seawater or are they readily dissolved by undersaturated seawater. Suspended mineral particles appear to be derived from shallow water bottom sediments and from river detritus. (Author)

The purpose of this investigation was to see what effect, if any, the starting length had on mass transfer from a cone. A blowdown supersonic wind tunnel was utilized to bring about a flow regime of approximately Mach 3.15. The experimental results of mass transfer from cones in supersonic flow are presented and a comparison to theoretical values is made. The cones used in the mass transfer tests were made of copper coated with p-dichlorobenzene. The amount of mass transfer was determined by weighing the cones before and after each test run. The error due to mass lost during transit from the scales to the test section and back was taken into account by later measuring an average mass transfer per unit time due to free convection alone. The results of the mass transfer tests are presented in a plot of mass transfer Colburn j factor as a function of Reynolds number. (Author), Research supported by Air Force Inst. of Tech., Wright-Patterson AFB, Ohio. Available only for Reference use at DDC field services. Copy not available for public sale.

This memorandum summarizes information on refractory materials and composites as presented at the Eighth Meeting of the Refractory Composites Working Group in Fort Worth, Texas, January 14-16, 1964. This memorandum is based on 45 papers covering a wide variety of subjects ranging from basic studies on oxidation mechanisms to the development of specific pieces of hardware. The papers are reviewed and discussed briefly within the framework of the following four broad areas: materials technology, process technology, specific hardware applications, and evaluation techniques. Included in the section on materials technology are discussions dealing with bulk refractory materials and coatedmetal systems. Hot spraying, chemical vapor deposition, powder processes, joining, and extrusion are discussed in the section on process technology. The specific hardware applications cover rocket-motor components, nose caps, leading edges, hot skins, and fasteners. (Author)

Salt spray tests were conducted with magnesiumsteel and magnesium-aluminum couples coated with alkyd and epoxy primers pigmented respectively with zinc chromate, strontium chromate, a mixture of zinc chromate and antimony oxide, and titanium dioxide. Results indicate that the optimum formulation for protecting the couples against corrosion is an epoxy-polyamide primer pigmented with the zinc chromate-antimony oxide mixture. Recommendation for the use of this coating is withheld pending the outcome of future work to determine its practicability as a primer for aircraft use. (Author)

Flexural strength data on laminates containing a series of new aryloxy alkoxysilanes are reported. Improvements in the dry, flexural strength of epoxy laminates were noted when integral blends containing the modified finishes were used. Solution application of aryloxy alkoxysilanes resulted in improved wet flexural strengths of epoxy laminates. Unsaturated aryloxy alkoxysilane finishes showed some improvements in both the dry and wet polyester laminate strengths. (Author)

The present concept of solid organic thin film lubrication is reviewed. The application of octadecylamine hydrochloride (ODA-HC1) to electric connector contacts was optimized by the inclusion of a heating step to consolidate the solution-deposited film, improving its adhesion, appearance and even, slightly, its frictional forces. A minimum film thickness for effective lubrication with good durability was found to exist for various surface finishes. (Author), Continuation of contracts DA-36-039-sc-85275 and DA-36-039-sc-89150.