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On the evolution of wear and temperature of some radioactive bronze-steel friction pairs
LITERATURE
AND CURRENT
Stability of Unloaded Gas-lubricated Bearings. ’ R. A. McCann, /. Basic Eng., 85 (4) (‘963) 513-518. The paper deals with a perfectly cylindrical, self-acting, gas-lubricated and unloaded jonrnal bearing. Complete stability criteria for the translational mode of oscillation are formulated and a method is given by which the ultimate stable operating speed may be found for arbitrary ambient pressure, viscosity, and bearing geometry. The nature of the stable motion is indicated. In addition, a simplified criterion and bearing motion are given for low-speed operation. Graphs which show the effect of design parameters on bearing forces are included as an aid in numerical calculations. Design
Data on TFE-Fabric Bearings.
H. A. Cress and J. R. Goldgraben, Design, 36 (1964) 154~161.
Machine
Fabric woven of TFE fibers-a high strength form of tetrafluoroethyleneis making inroads in many low-speed, high-load bearing applications. Typical uses include aircraftcontrol rod-end bearings, automotive balland-socket joints, and large, heavily-loaded radiotelescope bearings. Relatively few data were available in a form useful to the designer of this type of bearing. This article is a summary, which is arranged for maximum effectiveness as a design tool based both on the authors’ own tests and on a compilation of scattered data. Results from many investigators are evaluated and presented with common design parameters. The Magnetohydrodynamic Journal Bearing. D. C. Kuzma, /. Basic Eng., 85 (3) (1963) 424-428. An analysis of an infinite journal bearing is presented for the case of an electrically conducting fluid in the presence of a magnetic field. The magnetohydrodynamic form of Reynold’s bearing equation is derived and solved for the pressure distribution. The load carrying capacity is determined from the pressure distribution. Numerical data are 5. WEARAND WEAR The Effect of Interface Composition on the Wear Rate of Sapphire. E. J. Duwell and H. C. Butzke, ASLE Trans., 7 (1964) 101-108. The rate of wear of a single crystal sapphire sphere depends on crystal orientation and slide direction. This effect can be correlated with the shear mechanism of the crystal structure at elevated temperatures. On oxidized metal surfaces or on glass, sapphire appears to wear more rapidly than on freshlygenerated metal surfaces as a result of chemi-
EVENTS
presented faces.
for
473 nonconducting
bearing
sur-
4.2 Seals Fibrous Composite Materials for Extreme Environment Seals. L. L. Smith, lubrication Eng., 20 (1964) goIOj; 10 figs., 3 refs. Research was performed on the development and evaluation of composite materials suitable for use as static and dynamic seals at temperatures ranging from cryogenic to 1500°F and at pressures up to 5000 p.s.i. An example of a composite is silver reinforced with stainless steel fibers. The steps followed in making composite seals are described. The result is a pore-free, two-phase material with sufficient conformability to seal and sufficient strength to prevent extrusion under extreme temperature and pressure conditions. Physical properties, such as recovery and stress at deformations up to ten per cent, were determined for various composites at room temperature and ~ooo”F. The results show that the composites have improved recovery and strength characteristics compared to those of the corresponding pure fillers. Successful seal applications using composite materials include dynamic seals for rotating and reciprocating shafts, and static seals. Extending the Lip-type Seal Horizon. E. W. Fisher and D. H. Wilkinson, Lubrication Eng., 20 (1964) 87-93; I I figs., I table, 3 refs. This paper briefly references the two major shortcomings of elastomeric oil seals: fluid compatibility and temperature limitations. The role that polytetrafluoroethylene might play in resolving these problems is briefly mentioned. From here the development of a new oil seal is traced through the laboratory test stands to field usage. Critical areas are discussed and data presented showing progress in extending the horizon of the lip-type seal. Some of the design problems involved are mentioned. RESISTANCE
cal degradation. The effect of crystal orientation, which is associated with the shear strength of the crystal, is therefore decreased. Lubrication appears to decrease wear, but the effect of crystal orientation on wear rate persists. (See also Wear, 7 (1964) 67.) On the Evolution of Wear and Temperature of Some Radioactive Bronze-Steel Friction Pairs. D. Pavelescu and I. Iliuc, Rev. Mdcan. Appl., 8 (1963) 4333439. Wear, 7 (1964) 466-475
474
T.ITERATURE
AND
This paper describes results test apparatus permitting cording of wear rate and lubricating oil.
ohtaincd with a continuous rctcmpcraturc of
Hydrogen Penetration in Water-accelerated Fatigue of Rolling Surfaces. I.. Grunbvrg, Lj. T. Jamicson and I). Scott, Plzil. Alug., 8 (1963) Ijj3--I5OY. \2hcn a steel ball was rolled under load in contact with three similar balls, in the prosonce of a mineral oil containing tritinted water, both tritium and hydrogen were absorbed by the steel surfaces. The amount of absorbed tritium increased with the time of stressing. 2211the data for the amount of tritium absorbed by the halls fell on a single cm-w when the time of stressing was represented non-dimensionally by dividing it by the “mean pitting life” corresponding to the cxpcrimental conditions. The tritium content decreased by outward diffusion for the first five days after stressing, but thereafter remained constant. This observation can bc explained by the penetration of hydrogen produced by cracking of the oil in the presence of water. High-temperature Oil Evaluation in Fullscale Bearing Fatigue Tests. J. H. C;ustafson, Lz&iratin% E%g., -?o(rg(q) (,pOY; 7 figs. Full-scale bearing fatigue tests \vcrc conducted using a typical jet engine main shaft hearing with operating conditions as espetted in advance design engines. Four hightemperature fluids acre cvalusted for their effect on bearing fatigue life. The polyphcnyl cthcr fluid gave the best results with the B-IO life of 7 times the catalog rated lift. 13all retainer failures obtained indicate that acldi-
CURREXT
EVENTS
tional research is needed in the design of retainers and selection of the best rctaincr mat&al and lubricant combination. Metal Wear in Vibration Mills. tl. E. Rose and G. Jimbo, Tvans. Inst. Ckenz. Engrs. (LowiYo?z), 41 (1963) 147-158. For abstract see .ippZ. Meciz. NW., 17 (3) (1964) 203. Contribution to the Study of Corrosive Wear in Diesel Engines. (in French) I. l’ons, J. (‘hevitlon and J. Richard, Imt. I~vmz~ai.s du P&role, Ktv. iin%. Combmtibles Lzqttidas, 18 (1963) ~648-1672. Surfacc corrosion was isolated 1)~ autoradiograph?, and internal corrosion was studied by mctallographic investigation. The tests sho\\ed the offcctivcncss of having an illhibitor contained in the oil film betwvcen the piston and the cylinders of an engine. A Particular Wear Process of Sintered Tungsten Carbide. (in French) Ii. C‘ourtel and J. Guyonnct, Conzpt. Iietzd., 255 (1902) 16g+-,Jb96. Several sintered tungsten carbide pieces wcrc examined after prolonged ser\-ice in severe conditions of sliding and rolling friction (drilling tools, wire drawing belt-idler). h net of superficial cracks \vas observed, which covered the arcas subject to more intense mechanical stress. This phenomenon, which constitutes an ad\-axed state of wear of the piccos, can be attributed in the cases observed to the combined effect of thcrmic fatigue and pressure. The wear of guns and ceramics arc similar exsmpics. The mechanism involved in the cast: of sintered carbides seems to lw related to their particular structure.
35 (4) (1963) 481-487. .\n apparatus is described for bringing a rider specimen and a slider specimen into continuous sliding contact so that signifi~~llt tempcraturcs at the interface arc achievable. The design is such that the flow fields of heat in the specimens would be at most two-dimcnenginccring approximasional, i.e., within tions. This fact makes possible the measurement of temperatures of the spccimcns without disrupting the flow fields of heat.
With the growing realization that more w>ntrolled conditions arc needed to clarify mechanisms of friction and wwx, investigators have dcwloped techniques for studying sliding in a vacuum. Experiments at 10-6 torr have been adequate to demonstrate the vapor lubrication of graphite and the seizure and cold welding of metal surfaces free of oxidc. More recently, ultrahigh vacuum tcchniqucs have been applied to friction stud&. :I hakeable, all-metal ultrahigh vacuum apparatus is described for measuring friction at a pressure of ICI-!’ torr. The equipment has been successfully applied to studies of the &ding mechanism of MoSz.
The Application of Ultrahigh Vacuum Techniques to Studies of Friction and Wear. A. J. Haltner, General Electric Research Laboratory, Report No. 63-KL-3;32 C, (1903) IL pp.; S figs., *52refs.
Device for the Measurement of Friction at Ultrahigh Vacuum. E. E. ISrucschkc and 13. Beckman, 12rv. Sri. Ixstr., 34 (1963) 978-980.
Measurement of Pointwise Juncture Condition of Temperature at the Interface of Two Bodies in Sliding Contact. 1’. 1;. Ling and T. E. Simkins, .J. Basic Eng.,
J~ecw, 7 ('964) qtx-47.5
AND CURRENT
Stability of Unloaded Gas-lubricated Bearings. ’ R. A. McCann, /. Basic Eng., 85 (4) (‘963) 513-518. The paper deals with a perfectly cylindrical, self-acting, gas-lubricated and unloaded jonrnal bearing. Complete stability criteria for the translational mode of oscillation are formulated and a method is given by which the ultimate stable operating speed may be found for arbitrary ambient pressure, viscosity, and bearing geometry. The nature of the stable motion is indicated. In addition, a simplified criterion and bearing motion are given for low-speed operation. Graphs which show the effect of design parameters on bearing forces are included as an aid in numerical calculations. Design
Data on TFE-Fabric Bearings.
H. A. Cress and J. R. Goldgraben, Design, 36 (1964) 154~161.
Machine
Fabric woven of TFE fibers-a high strength form of tetrafluoroethyleneis making inroads in many low-speed, high-load bearing applications. Typical uses include aircraftcontrol rod-end bearings, automotive balland-socket joints, and large, heavily-loaded radiotelescope bearings. Relatively few data were available in a form useful to the designer of this type of bearing. This article is a summary, which is arranged for maximum effectiveness as a design tool based both on the authors’ own tests and on a compilation of scattered data. Results from many investigators are evaluated and presented with common design parameters. The Magnetohydrodynamic Journal Bearing. D. C. Kuzma, /. Basic Eng., 85 (3) (1963) 424-428. An analysis of an infinite journal bearing is presented for the case of an electrically conducting fluid in the presence of a magnetic field. The magnetohydrodynamic form of Reynold’s bearing equation is derived and solved for the pressure distribution. The load carrying capacity is determined from the pressure distribution. Numerical data are 5. WEARAND WEAR The Effect of Interface Composition on the Wear Rate of Sapphire. E. J. Duwell and H. C. Butzke, ASLE Trans., 7 (1964) 101-108. The rate of wear of a single crystal sapphire sphere depends on crystal orientation and slide direction. This effect can be correlated with the shear mechanism of the crystal structure at elevated temperatures. On oxidized metal surfaces or on glass, sapphire appears to wear more rapidly than on freshlygenerated metal surfaces as a result of chemi-
EVENTS
presented faces.
for
473 nonconducting
bearing
sur-
4.2 Seals Fibrous Composite Materials for Extreme Environment Seals. L. L. Smith, lubrication Eng., 20 (1964) goIOj; 10 figs., 3 refs. Research was performed on the development and evaluation of composite materials suitable for use as static and dynamic seals at temperatures ranging from cryogenic to 1500°F and at pressures up to 5000 p.s.i. An example of a composite is silver reinforced with stainless steel fibers. The steps followed in making composite seals are described. The result is a pore-free, two-phase material with sufficient conformability to seal and sufficient strength to prevent extrusion under extreme temperature and pressure conditions. Physical properties, such as recovery and stress at deformations up to ten per cent, were determined for various composites at room temperature and ~ooo”F. The results show that the composites have improved recovery and strength characteristics compared to those of the corresponding pure fillers. Successful seal applications using composite materials include dynamic seals for rotating and reciprocating shafts, and static seals. Extending the Lip-type Seal Horizon. E. W. Fisher and D. H. Wilkinson, Lubrication Eng., 20 (1964) 87-93; I I figs., I table, 3 refs. This paper briefly references the two major shortcomings of elastomeric oil seals: fluid compatibility and temperature limitations. The role that polytetrafluoroethylene might play in resolving these problems is briefly mentioned. From here the development of a new oil seal is traced through the laboratory test stands to field usage. Critical areas are discussed and data presented showing progress in extending the horizon of the lip-type seal. Some of the design problems involved are mentioned. RESISTANCE
cal degradation. The effect of crystal orientation, which is associated with the shear strength of the crystal, is therefore decreased. Lubrication appears to decrease wear, but the effect of crystal orientation on wear rate persists. (See also Wear, 7 (1964) 67.) On the Evolution of Wear and Temperature of Some Radioactive Bronze-Steel Friction Pairs. D. Pavelescu and I. Iliuc, Rev. Mdcan. Appl., 8 (1963) 4333439. Wear, 7 (1964) 466-475
474
T.ITERATURE
AND
This paper describes results test apparatus permitting cording of wear rate and lubricating oil.
ohtaincd with a continuous rctcmpcraturc of
Hydrogen Penetration in Water-accelerated Fatigue of Rolling Surfaces. I.. Grunbvrg, Lj. T. Jamicson and I). Scott, Plzil. Alug., 8 (1963) Ijj3--I5OY. \2hcn a steel ball was rolled under load in contact with three similar balls, in the prosonce of a mineral oil containing tritinted water, both tritium and hydrogen were absorbed by the steel surfaces. The amount of absorbed tritium increased with the time of stressing. 2211the data for the amount of tritium absorbed by the halls fell on a single cm-w when the time of stressing was represented non-dimensionally by dividing it by the “mean pitting life” corresponding to the cxpcrimental conditions. The tritium content decreased by outward diffusion for the first five days after stressing, but thereafter remained constant. This observation can bc explained by the penetration of hydrogen produced by cracking of the oil in the presence of water. High-temperature Oil Evaluation in Fullscale Bearing Fatigue Tests. J. H. C;ustafson, Lz&iratin% E%g., -?o(rg(q) (,pOY; 7 figs. Full-scale bearing fatigue tests \vcrc conducted using a typical jet engine main shaft hearing with operating conditions as espetted in advance design engines. Four hightemperature fluids acre cvalusted for their effect on bearing fatigue life. The polyphcnyl cthcr fluid gave the best results with the B-IO life of 7 times the catalog rated lift. 13all retainer failures obtained indicate that acldi-
CURREXT
EVENTS
tional research is needed in the design of retainers and selection of the best rctaincr mat&al and lubricant combination. Metal Wear in Vibration Mills. tl. E. Rose and G. Jimbo, Tvans. Inst. Ckenz. Engrs. (LowiYo?z), 41 (1963) 147-158. For abstract see .ippZ. Meciz. NW., 17 (3) (1964) 203. Contribution to the Study of Corrosive Wear in Diesel Engines. (in French) I. l’ons, J. (‘hevitlon and J. Richard, Imt. I~vmz~ai.s du P&role, Ktv. iin%. Combmtibles Lzqttidas, 18 (1963) ~648-1672. Surfacc corrosion was isolated 1)~ autoradiograph?, and internal corrosion was studied by mctallographic investigation. The tests sho\\ed the offcctivcncss of having an illhibitor contained in the oil film betwvcen the piston and the cylinders of an engine. A Particular Wear Process of Sintered Tungsten Carbide. (in French) Ii. C‘ourtel and J. Guyonnct, Conzpt. Iietzd., 255 (1902) 16g+-,Jb96. Several sintered tungsten carbide pieces wcrc examined after prolonged ser\-ice in severe conditions of sliding and rolling friction (drilling tools, wire drawing belt-idler). h net of superficial cracks \vas observed, which covered the arcas subject to more intense mechanical stress. This phenomenon, which constitutes an ad\-axed state of wear of the piccos, can be attributed in the cases observed to the combined effect of thcrmic fatigue and pressure. The wear of guns and ceramics arc similar exsmpics. The mechanism involved in the cast: of sintered carbides seems to lw related to their particular structure.
35 (4) (1963) 481-487. .\n apparatus is described for bringing a rider specimen and a slider specimen into continuous sliding contact so that signifi~~llt tempcraturcs at the interface arc achievable. The design is such that the flow fields of heat in the specimens would be at most two-dimcnenginccring approximasional, i.e., within tions. This fact makes possible the measurement of temperatures of the spccimcns without disrupting the flow fields of heat.
With the growing realization that more w>ntrolled conditions arc needed to clarify mechanisms of friction and wwx, investigators have dcwloped techniques for studying sliding in a vacuum. Experiments at 10-6 torr have been adequate to demonstrate the vapor lubrication of graphite and the seizure and cold welding of metal surfaces free of oxidc. More recently, ultrahigh vacuum tcchniqucs have been applied to friction stud&. :I hakeable, all-metal ultrahigh vacuum apparatus is described for measuring friction at a pressure of ICI-!’ torr. The equipment has been successfully applied to studies of the &ding mechanism of MoSz.
The Application of Ultrahigh Vacuum Techniques to Studies of Friction and Wear. A. J. Haltner, General Electric Research Laboratory, Report No. 63-KL-3;32 C, (1903) IL pp.; S figs., *52refs.
Device for the Measurement of Friction at Ultrahigh Vacuum. E. E. ISrucschkc and 13. Beckman, 12rv. Sri. Ixstr., 34 (1963) 978-980.
Measurement of Pointwise Juncture Condition of Temperature at the Interface of Two Bodies in Sliding Contact. 1’. 1;. Ling and T. E. Simkins, .J. Basic Eng.,
J~ecw, 7 ('964) qtx-47.5