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Bonding of molybdenum disulfide to various materials to form a solid lubricating film 1: the bonding mechanism

Description: Report presenting the use of molybdenum disulfide as a solid film lubricant in applications where designs or temperatures preclude liquid lubricants is dependent on successful bonding of the powder to the surface to be lubricated. An investigation was conducted to determine the basic mechanism of bonding and to extend application of the bonding to a variety of materials. Results regarding an examination of electron diffraction of MoS2 dusted and rubbed on steel, adherence of dry powders to metals, chemical action in bonding mechanism, other resin-forming liquid vehicles, bonding of MoS2 and other powders to various materials, and analysis of solid film by electron diffraction are provided.
Date: February 1952
Creator: Godfrey, Douglas & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Friction of possible solid lubricants with various crystal structures

Description: Report presenting a number of possible solid lubricants with various crystal structures tested in a low-speed, high-load, friction apparatus under conditions of continuous sliding. None of the solids tested were as effective as MoS2 but were at least as effective as zinc stearate and graphite in these tests. Results regarding common lubricants, layer-lattice structure, and low-shear-strength solids without layer-lattice structure are provided.
Date: December 1954
Creator: Peterson, Marshall B. & Johnson, Robert L.
Partner: UNT Libraries Government Documents Department

Bonding of molybdenum disulfide to various materials to form a solid lubricating film 2: friction and endurance characteristics of films bonded by practical methods

Description: Report exploring the use of molybdenum disulfide as a solid-film lubricant, especially in applications where designs or higher temperatures preclude liquid lubricants, because of its good frictional and thermal properties. An investigation was conducted to determine practical methods of bonding MoS2 to materials to form solid-film lubricants and friction and endurance characteristics of films so formed.
Date: October 1952
Creator: Godfrey, Douglas & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Friction at high sliding velocities of surfaces lubricated with sulfur as an additive

Description: Report presenting an investigation of friction occurring at high sliding velocities of sulfur-type extreme-pressure lubricants. Experimental evidence is presented that indicates the existence of a limiting and critical condition of sliding velocity. Results regarding the effect of sliding velocity for initial hertz stress of 126,000 pounds per square inch and effect of sliding velocity for variable loads are provided.
Date: October 1948
Creator: Johnson, Robert L.; Swikert, Max A. & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Effect of temperature on rolling-contact fatigue life with liquid and dry powder lubricants

Description: Report presenting an investigation of the effect of temperature using di(2-ethylhexyl) sebacate lubricant and dry powder lubricants on rolling-contact fatigue life on AISI M-1 tool-steel balls in the rolling-contact fatigue spin rig at maximum theoretical Hertz stress levels of 650,000 and 725,000 pounds per square inch in compression.
Date: January 1958
Creator: Carter, Thomas L.
Partner: UNT Libraries Government Documents Department

Effect of lubricant base stock on rolling-contact fatigue life

Description: Report presenting five lubricants of different base stock tested using groups of 1/2-inch air-melt AISI M-1 tool-steel balls under rolling-contact fatigue conditions in the fatigue spin rig. A methyl silicone, mineral oil, glycol, sebacate, and adipate were used. All other test conditions were held constant at a test temperature of 100 degrees Fahrenheit and a maximum theoretical Hertz stress of 725,000 pounds per square inch in compression.
Date: February 1958
Creator: Carter, Thomas L.
Partner: UNT Libraries Government Documents Department

Effect of lubricant viscosity on rolling-contact fatigue life

Description: Report presenting a series of rolling-contact fatigue tests conducted in a bench rig at the Lewis laboratory. Four paraffin-base mineral oils of varying viscosity were used as lubricants. A continuous trend toward longer lift was observed with increasing lubricant viscosity over the range studied.
Date: October 1957
Creator: Carter, Thomas L.
Partner: UNT Libraries Government Documents Department

Effect of high bulk temperatures on boundary lubrication of steel surfaces by synthetic fluids

Description: "High operating temperatures of new and projected turbine engines require that synthetic fluids be used as lubricants, because these fluids have better thermal stability and viscosity-temperature characteristics than petroleum oils have. An experimental study was conducted to learn the effect of high lubricant bulk temperatures on the boundary lubricating effectiveness of various types of synthetic fluid" (p. 1).
Date: May 1953
Creator: Murray, S. F.; Johnson, Robert L. & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Lubricants of reduced flammability

Description: Report presenting information regarding lubricants of reduced flammability, including the determination of the change in spontaneous ignition temperature, stability testing, and a practical method for synthesizing them.
Date: January 1954
Creator: Frank, Charles E.; Swarts, Donald E. & Mecklenborg, Kenneth T.
Partner: UNT Libraries Government Documents Department

Effective lubrication range for steel surfaces boundary lubricated at high sliding velocities by various classes of synthetic fluids

Description: Report presenting an exploration of synthetic lubricants, which involved studying the effects of a wide range of sliding velocities on boundary lubrication. The data showed that a number of synthetics, including diesters, polyethers, a silicate ester, and a phosphonate ester as well as a silicone-diester blend are more effective boundary lubricants at high sliding velocities than comparable petroleum oils.
Date: December 1952
Creator: Johnson, Robert L.; Swikert, Max A. & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Rise of Air Bubbles in Aircraft Lubricating Oils

Description: Note presenting measurements of the rates of rise of small air bubbles, up to 2 millimeters in diameter, at room temperature in an undoped oil, in the same oil containing foam inhibitors, and in an oil containing lubricating additives. The apparent diameter of the air bubbles was measured visually through an ocular micrometer on a traveling telescope. A method is derived to calculate the thickness of the liquid shell which would have to move with the bubbles in the doped oils to account for the abnormally slow velocity.
Date: February 1950
Creator: Robinson, J. V.
Partner: UNT Libraries Government Documents Department

Review of Current and Anticipated Lubricant Problems in Turbojet Engines

Description: Memorandum presenting a review of the current and anticipated lubricant problems as related to aircraft turbojet engines, which has indicated that the current and anticipated bearing operating temperature ranges to be met are specified. The most promising approaches, including types of lubricants and temperatures, are provided.
Date: April 20, 1951
Partner: UNT Libraries Government Documents Department

High-Temperature Lubricants and Bearings for Aircraft Turbine Engine

Description: Memorandum presenting a consideration of the problems, research status, and future possibilities for high-temperature lubricants and bearings for aircraft turbine engines. The greater heat loads imposed by high-performance engines and practical limitation on cooling will result in increased operating temperatures for bearings and lubricants.
Date: July 19, 1954
Creator: NACA Subcommittee on Lubrication and Wear
Partner: UNT Libraries Government Documents Department

Friction, wear, and surface damage of metals as affected by solid surface films

Description: "As predicted by friction theory, experiments showed that friction and surface damage of metals can be reduced by solid surface films. The ability of materials to form surface films that prevent welding was a very important factor in wear of dry and boundary lubricated surfaces. Films of graphitic carbon on cast irons, NiO on nickel alloys, and FeO and Fe(sub 3)O(sub 4) on ferrous materials were found to be beneficial. Abrasive films such as Fe(sub 2)O(sub 3) or MoO(sub 3) were definitely detrimental. It appears that the importance of oxide films to friction and wear processes has not been fully appreciated" (p. 93).
Date: February 10, 1955
Creator: Bisson, Edmond E.; Johnson, Robert L.; Swikert, Max A. & Godfrey, Douglas
Partner: UNT Libraries Government Documents Department

Evaluation of a silicone-diester lubricant in bench studies and in a turbopropeller engine

Description: Report presenting an investigation of a silicone-diester blend (SD-17) in various bench studies and in a turbopropeller engine to determine its suitability as a lubricant for aircraft engines. The performance of the fluid was satisfactory during more than 17 hours of operation in a T-38 engine with power levels from 1745 to 2400 horsepower. Results regarding bench studies and turbopropeller engine study are provided.
Date: May 4, 1954
Creator: Johnson, Robert L.; Murray, S. F. & Bisson, Edmund E.
Partner: UNT Libraries Government Documents Department

Effect of chemical reactivity of lubricant additives on friction and surface welding at high sliding velocities

Description: Report presenting an investigation of the effect of chemical reactivity of lubricant additives on friction at high sliding velocities. The investigation was conducted with a kinetic-friction apparatus consisting of an elastically restrained spherical rider specimen sliding on a rotating steel disk lubricated with cetane containing lubricant additives of different chemical reactivities. Results regarding chlorine compounds and sulfur compounds are provided.
Date: August 1950
Creator: Bisson, Edmond E.; Swikert, Max A. & Johnson, Robert L.
Partner: UNT Libraries Government Documents Department

Bonded lead monoxide films as solid lubricants for temperatures up to 1250 degrees F

Description: Report presenting a friction, wear, and endurance-lift study made with bonded films of mixed oxides containing lead monoxide (PbO) as the main component. The coatings lubricated over the entire temperature range, but were far more effective from 500 to 1250 degrees Fahrenheit than at the lower temperatures. Results regarding the effect of silica additions on coating formation, determination of coating composition, effect of coating thickness on friction and wear, effect of temperature on friction and wear, and endurance properties are provided.
Date: May 7, 1957
Creator: Sliney, Harold E. & Johnson, Robert L.
Partner: UNT Libraries Government Documents Department

Investigation of Lubricants Under Boundary Friction

Description: Numerous observations of such lubrication processes within range of boundary friction on journal bearings and gear tooth profiles have strengthened the supposition that it should be possible to study the attendant phenomena with engineering methods and equipment. These considerations formed the basis of the present studies, which have led to the discovery of relations governing the suitability of bearing surfaces and the concept of "lubricating quality.".
Date: May 1942
Creator: Heidebroek, E. & Pietsch, E.
Partner: UNT Libraries Government Documents Department

Variation With Temperature of Surface Tension of Lubricating Oils

Description: Note presenting surface-tension measurements from room temperature to 180 degrees Celsius of a series of aeronautical lubricating oils and a few liquids of associated interest. The critical temperatures of the liquids are calculated and a general classification of existing oils into three groups is provided.
Date: February 1950
Creator: Ross, Sydney
Partner: UNT Libraries Government Documents Department

Growth, Structure and Tribological Properties of Atomic Layer Deposited Lubricious Oxide Nanolaminates

Description: Friction and wear mitigation is typically accomplished by introducing a shear accommodating layer (e.g., a thin film of liquid) between surfaces in sliding and/or rolling contacts. When the operating conditions are beyond the liquid realm, attention turns to solid coatings. Solid lubricants have been widely used in governmental and industrial applications for mitigation of wear and friction (tribological properties). Conventional examples of solid lubricants are MoS2, WS2, h-BN, and graphite; however, these and some others mostly perform best only for a limited range of operating conditions, e.g. ambient air versus dry nitrogen and room temperature versus high temperatures. Conversely, lubricious oxides have been studied lately as good potential candidates for solid lubricants because they are thermodynamically stable and environmentally robust. Oxide surfaces are generally inert and typically do not form strong adhesive bonds like metals/alloys in tribological contacts. Typical of these oxides is ZnO. The interest in ZnO is due to its potential for utility in a variety of applications. To this end, nanolaminates of ZnO, Al2O3, ZrO2 thin films have been deposited at varying sequences and thicknesses on silicon substrates and high temperature (M50) bearing steels by atomic layer deposition (ALD). The top lubricious, nanocrystalline ZnO layer was structurally-engineered to achieve low surface energy {0002}-orientated grain that provided low sliding friction coefficients (0.2 to 0.3), wear factors (range of 10-7 to 10-8 mm3/Nm) and good rolling contact fatigue resistance. The Al2O3 was intentionally made amorphous to achieve the {0002} preferred orientation while {101}-orientated tetragonal ZrO2 acted as a high toughness/load bearing layer. It was determined that the ZnO defective structure (oxygen sub-stoichiometric with growth stacking faults) aided in shear accommodation by re-orientating the nanocrystalline grains where they realigned to create new friction-reducing surfaces. Specifically, high resolution transmission electron microscopy (HRTEM) inside the wear surfaces revealed in an increase in ...
Date: December 2010
Creator: Mensah, Benedict Anyamesem
Partner: UNT Libraries

Tethered Lubricants for Small Systems

Description: The objective of this research project is two-fold. First, to fundamentally understand friction and relaxation dynamics of polymer chains near surfaces; and second, to develop novel self-lubricated substrates suitable for MEMS devices. During the three-year performance period of this study the PI and his students have shown using theory and experiments that systematic introduction of disorder into tethered lubricant coatings (e.g. by using self-assembled monolayer (SAM) mixtures or SAMs with nonlinear, branched architectures) can be used to significantly reduce the friction coefficient of a surface. They have also developed a simple procedure based on dielectric spectroscopy for quantifying the effect of surface disorder on molecular relaxation in lubricant coatings. Details of research accomplishments in each area of the project are described in the body of the report.
Date: January 9, 2006
Creator: Archer, Lynden A.
Partner: UNT Libraries Government Documents Department

Effects of Minimum Quantity Lubrication in Drilling 1018 Steel.

Description: A common goal for industrial manufacturers is to create a safer working environment and reduce production costs. One common method to achieve this goal is to drastically reduce cutting fluid use in machining. Recent advances in machining technologies have made it possible to perform machining with minimum-quantity lubrication (MQL). Drilling takes a key position in the realization of MQL machining. In this study the effects of using MQL in drilling AISI 1018 steel with HSS tools using a vegetable based lubricant were investigated. A full factorial experiment was conducted and regression models were generated for both surface finish and hole size. Lower surface roughness and higher tool life were observed in the lowest speed and feed rate combination.
Date: December 2008
Creator: Shaikh, Vasim
Partner: UNT Libraries