- Email: [email protected]
Materials research for lubricants and heat transfer fluids
SYSTEMATIC ABSTRACTS range of -65”F-goo”F. The most promising fluids are the higher phenyl content methyl silicones. Other potentially promising fluids are silphenylenes, polyphenyl ethers, chaintype polyphenyls, and phosphonitrilic chloride polymers and their complexes. Mass spectograph studies on polyphenyls reveal that these materials have unusual stability under electron impact. Although the high molecular weight polyphenyls are solids with relatively high melting points, a mixed melting point study shows marked lowering in melting points on melts of mixtures of these materials. Imide-thickened greases, despite their apparently good high temperature characteristics as indicated by dropping points above 700’F. do not give satisfactory results in the high temperature bearing performance tests. This is true in both phenyl ethers and phenyl silicones. Development of a Prototype Radiation Resistant Bearing and Gear Lubricant. C. L. Mahony (Wright-Patterson AFB, Ohio, Directorate of Materials and Processes), (1962) 119 pp., 28 refs.; N 62-13209 Shell Dev. Co., Emeryville, Calif., T.P.A ., 2 (9) (1962) 451-452.
The polyphenyl &hers have the physical properties and stability to permit their use in environments far too severe for conventional lubricants. While their high-speed bearing performance is good, viscosities at high temperatures are too low to give sufficient load-carrying capacity for some gear applications, so additives have been examined as a means of improving their gear loadcarrying capacity. Suitable additives must meet the conflicting requirements of high activity towards metal surfaces and little effect on the stability of the ethers. No additive examined completely satisfied these requirements. Only aromatic derivatives had sufficient stability and these materials generally did not improve load-carrying capacity. However, some aromatic phosphate derivatives, when used in high concentrations (~-IO%), appreciably improved the lubrication properties and their effects on the oxidation, radiation and thermal stability of the polyphenyl ethers was low. Such additives may bc suitable where requirements arc low. Materials Research for Lubricants and Heat Transfer Fluids. K. R. Mecklenburg (Wright-Patterson AFB, Ohio, Directorate of Materials and Processes), (1962) 30 pp.; 3 refs., N 62-11162, T.P.A. 2 (4) (1962)
153.
Friction data are presented for copper on copper and for titanium on nickel for very low sliding speeds and light loads. The stickslip apparatus used to obtain these data is described. Results are given for the initial
85
part of an investigation in which the film conductance will bc determined for liquid metals. A preprototype liquid metal boiler was operated at temperatures up to 1630’F with sodium. The design of a prototype liquid metal boiler for use in the next step of this work at temperatures up to 18oo’F is described. Techniques used to handle sodium are outlined. Bearing life data are included for experimental greases ruqathigh temperatures and speeds in the Pope Spindle. Screening runs with experimental grease made on the Navy Spindle at 350’F were not effective in selecting greases which would consistintly run more than a few years at high tempcratures in the Pope Spindle. Wear scar data from the Four-Ball Wear Tester are given for experimental fluids. The Effect of Nuclear Radiation on Lubricants and Hydraulic Fluids. S. L. Cosgrave and R. L. Dueltgcn (Radiation
Effects Information Center, Battelle Mem. Inst.), (1961) 113 pp., III refs.; N 62.15268, T.P.A., 2, (14) (1962) 775. Radiation studies on organic compounds considered significant to lubricant and hydraulic-fluid development are reviewed and their significance is discussed. Radiationresistant gas-turbine-lubricant studies have led to the development of polyphenyl ethers, alkylated aromatics, and alkylated aromatic ethers. Meta-linked polyphenyl ethers show promise for use between o” and 8oo”~9000 and at dosages up to 1011 ergs g-i (C). Inhibited alkylated aromatics, while showing pour points to -50°F suffer from excessive high-temperature coking tendencies. Inhibited aromatic ethers are less radiation-resistant than the polyphenyl ethers, but have a uscful temperature range of about - 35”-600°F. Calresearch 59R-439 hydraulic fluid, an inhibited isopropyl-r,g-diphenylnonane, is the most promising radiation-resistant formulation. The extremely stable polyphenyl ethers should find application where higher pour points (about 5°F) can be tolerated. Commercial dry-film lubricants appear to bc unaffected by gamma exposures to 2 1011 ergs g-i(C). .4lkali-metal silicates appear to be satisfactory binders for high temperature applications, and exposures to 4.4 . 1011 ergs g-i (C) or higher. Metal matrices may be needed for temperatures of rooo°F and simultaneous exposures to 1012 ergs g-i (C). Most important is the need for evaluating lubricants and hydraulic fluids under dynamic (in-source) conditions. Anti-Friction Bearing Lubricant Requirements in High Altitude Environments. R. A. Coit and S. S. Sorem, Lubrication Eng., r8 (IO) (1962) 438-442; 3 figs., 3 tables, 2 refs.
The lubrication problem at extremely low pressures, equivalent to IOO miles altitude, Wear, 6 (1963) 81-90
The polyphenyl &hers have the physical properties and stability to permit their use in environments far too severe for conventional lubricants. While their high-speed bearing performance is good, viscosities at high temperatures are too low to give sufficient load-carrying capacity for some gear applications, so additives have been examined as a means of improving their gear loadcarrying capacity. Suitable additives must meet the conflicting requirements of high activity towards metal surfaces and little effect on the stability of the ethers. No additive examined completely satisfied these requirements. Only aromatic derivatives had sufficient stability and these materials generally did not improve load-carrying capacity. However, some aromatic phosphate derivatives, when used in high concentrations (~-IO%), appreciably improved the lubrication properties and their effects on the oxidation, radiation and thermal stability of the polyphenyl ethers was low. Such additives may bc suitable where requirements arc low. Materials Research for Lubricants and Heat Transfer Fluids. K. R. Mecklenburg (Wright-Patterson AFB, Ohio, Directorate of Materials and Processes), (1962) 30 pp.; 3 refs., N 62-11162, T.P.A. 2 (4) (1962)
153.
Friction data are presented for copper on copper and for titanium on nickel for very low sliding speeds and light loads. The stickslip apparatus used to obtain these data is described. Results are given for the initial
85
part of an investigation in which the film conductance will bc determined for liquid metals. A preprototype liquid metal boiler was operated at temperatures up to 1630’F with sodium. The design of a prototype liquid metal boiler for use in the next step of this work at temperatures up to 18oo’F is described. Techniques used to handle sodium are outlined. Bearing life data are included for experimental greases ruqathigh temperatures and speeds in the Pope Spindle. Screening runs with experimental grease made on the Navy Spindle at 350’F were not effective in selecting greases which would consistintly run more than a few years at high tempcratures in the Pope Spindle. Wear scar data from the Four-Ball Wear Tester are given for experimental fluids. The Effect of Nuclear Radiation on Lubricants and Hydraulic Fluids. S. L. Cosgrave and R. L. Dueltgcn (Radiation
Effects Information Center, Battelle Mem. Inst.), (1961) 113 pp., III refs.; N 62.15268, T.P.A., 2, (14) (1962) 775. Radiation studies on organic compounds considered significant to lubricant and hydraulic-fluid development are reviewed and their significance is discussed. Radiationresistant gas-turbine-lubricant studies have led to the development of polyphenyl ethers, alkylated aromatics, and alkylated aromatic ethers. Meta-linked polyphenyl ethers show promise for use between o” and 8oo”~9000 and at dosages up to 1011 ergs g-i (C). Inhibited alkylated aromatics, while showing pour points to -50°F suffer from excessive high-temperature coking tendencies. Inhibited aromatic ethers are less radiation-resistant than the polyphenyl ethers, but have a uscful temperature range of about - 35”-600°F. Calresearch 59R-439 hydraulic fluid, an inhibited isopropyl-r,g-diphenylnonane, is the most promising radiation-resistant formulation. The extremely stable polyphenyl ethers should find application where higher pour points (about 5°F) can be tolerated. Commercial dry-film lubricants appear to bc unaffected by gamma exposures to 2 1011 ergs g-i(C). .4lkali-metal silicates appear to be satisfactory binders for high temperature applications, and exposures to 4.4 . 1011 ergs g-i (C) or higher. Metal matrices may be needed for temperatures of rooo°F and simultaneous exposures to 1012 ergs g-i (C). Most important is the need for evaluating lubricants and hydraulic fluids under dynamic (in-source) conditions. Anti-Friction Bearing Lubricant Requirements in High Altitude Environments. R. A. Coit and S. S. Sorem, Lubrication Eng., r8 (IO) (1962) 438-442; 3 figs., 3 tables, 2 refs.
The lubrication problem at extremely low pressures, equivalent to IOO miles altitude, Wear, 6 (1963) 81-90