Investigation of the frictional behavior of solid lubricants in air and in high vacuum. (in German)

Investigation of the frictional behavior of solid lubricants in air and in high vacuum. (in German)

feasibility of lubricating worm gears with bonded solid-film lubricants. .2n apparatus for ~~~t~rr~lillill~ gear efficiency- and lubricant film wear-l...

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feasibility of lubricating worm gears with bonded solid-film lubricants. .2n apparatus for ~~~t~rr~lillill~ gear efficiency- and lubricant film wear-life was fabricatctl. Several tests using conventional oil lubrication tserc cot,ductcd to establish baseline gear efficiency data. Efficiency and wear-lift tests were made with four solid-lubricant films, two of them incorporating %I& and Sb&)s in organic polyimidc resin binders, and two usin:: ILl&, grayhitc and gold or bismuth in an al~~~ni~~iu~n phosphate or sodium silicate binder. Experimental data indicate that solid-film lubrication of worm gears is feasible, without a serious loss of efficiency in situations xvhcre limited wear-life is ncccptablc. Investigation of the Frictional Behavior of Solid Lubricants in Air and in Hiih Vacuum. (in German) G. Spcngler, W. Heliwig and F. Wunsch, Drufsche

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wxi Rawnfuhrt, [email protected]

68-18,

1968, 25 pp., 9 figs.. L tabs., 5 refs., DM 6.80. Special problems of lubrication under cxtremc conditions in aviation and space may often be solved only by the employment of solid lubricants. This paper describes the lubricating behavior of sciectcd solid Iubricants in air and in high vacuum, as invcstigated in plain bcarin#s. The solid lubricant layers are produced on the plain bearing axles and the relation bettveen layer build-up and life of the solid films is investigated. The specially produced iIloS~!PT FE double-layers mere found to be the optimum ~o~Ilbinati~)~l at present. The experiments have been made using an especially designed IYliV-apparatus to determine sliding, friction and wear characteristics under increased bearing load. Chemical Interactions Involved in the Formation of Oxidation-resistant Solidlubricant Composites. D. J. Roes and B. Chamberlain, A.SLIr Tram., II (z) (1968) 13 [-~.jq; I.+ figs., 5 tables, 4 refs. Solid lubricating compacts of tungsten diselcnide-gallium alloys are currently under development for use as self-lubricating in high-speed. hiph-temperature members ball-bearing systems. The material is of considerable interest due to the fact that it resists oxidation at temperatures three times higher than pure tungsten diselenide. This paper discusses initial studies of the physical and chemical changes that occur in these compacts during a heat-treating cycle required in their fabrication. Speculations regarding the mechanism responsible for their oxidation resistsncc are presented. CompositeSelf-1ubricatingBearingMaterial.s. J. I<. Lancaster, PYW. Inst. Mech. Engvs., 182, Pf. I (Ig6yb8) Preprint 1’2/68. A4survey is given of progress in the developWenr, TZ (1968) 299-305

mcnt of self-lubricating materials for loadcarrying components (bcarin~s and gears) or for transfer lubrication (rollill~.element Irearinfi rctaincrs). Various methods for producing composites of inorganic solid lubricants, metal-, polymers, carbons ant1 ceramics arc briefly described, and some suggestions for further work arc includctl

Bearings Reference Machine

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Experiments with Hydrodynamic Journal Bearings of Various Materials and Designs in Sodium at Temperatures to SOO’F. 1:. T. Schuller, W. J. Anderson and Z. Nemeth, _iSLE Tvans., II (z) (1968) rqo-154; r.3 figs., 5 tables, 9 rcfs. Experiments were conducted with I 5 in. diameter hydrodynamic jourual bearings in liquid sodium at 500 ’ and 800~ F, speeds to IZ,OOO rev./min and unitloadsto ,?I o.s.i. The stahitity characteristics of five different geoi3tetries and the wear and seizure propertics of several material combinations were investigated. Tilting pad bearings were most stable. Combinations of a cobalt alloy with nickel alloys or with a titanium carbide ccrmet showed the best wear and seizure properties. Friction Torque of Bali Bearings in Vacuum with Seven Polytetrafluaoethylene-composition Retainer Materials. H. \\‘. Scibbe, D. C. Glenn and W. J. 24ndcrson. Xr3S.-1 7‘crh. ;l’oli, /I-.$3.55, (Feb. 1968) 18 pp. Propagation of Surface Disturbances on Radially-loaded Disks. 1). L. Alexander, .-ISLE: Trays., 11 (I) (1968) 72-80; q figs., 2 tables, 2 refs. i\Jl analysis is prCSented showing the mannel in which an initial point disturbance on the surface of one disk of a pair of radiallyloaded disks rolling and slidiug in contact will grow and propagate other surface disturbances on both disks. fn the analysis it is assumed that an area becoming disturbed will be able to pause disturbances on surfaces which come into contact with it. The patterns of the disturbances formed have been compared with scuff patterns on pairs of failed disks, and significant similarities arc shown. The number of disturbarmcs and the spacing of the leading edges of the disturbances are similar to the number and spacing of the scuff marks. The analysis gives lengths of the disturbances somewhat longer than the scuff marks. It is concluded that the analysisishelp-