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Research program on high vacuum friction
r,f Rardnc5scs. Effect of Hardness, Surface Finish, and Grain Size on Rolling-Contact Fatigue Life of M-50 Bearing Steel.
Some Recent Experiments on the Friction, Wear and Deformation of Solids. F. I’. Rowden. S.z4.I:. Trans., 67 (1959) Qjo658: ‘4 figs., I table, 9 refs. Experiments ha\-e been conducted at Cambridge IJniversitp which probed the sliding friction and wear of nonmetals, and the deformation of solids at high rates of strain. The author was particularly interested in the deformation and damage of metals and nonmetals under high-speed liquid impact. The findings will contribute to the development of materials that can withstand the friction of high-speed space flight. The author discusses the sliding friction and wear of wood, diamond, glass, rubber, and metallic carbides. In the last part of the paper, he describes the high-speed problems arising when solids are deformed very rapidly. Reviving the Classical Theory of Friction by aModern Dislocation Theory of Deformation Revision. John H. Dismant.J. AppZ. Phys., 31 (1960) 221 ; 4 refs. Letter to the Editor. Hypothesis about the influence of dislocations on work hardening of thin films under conditions of sliding friction. Author assumes essentially elastic forces to be operative in friction. (See also Thesis, Utah 19,j.j) Research ProgramonHighVacuum Friction. S. Hansen, WT. Jones and -4. Stephenson, Litton
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J.abovafo&s did Refit. 2907, (1959) I48 pp. A twelve-month program directed towards the study of surface friction under conditions of high vacuum (IO--~ to ~0-6 mm Hg) has hrcn carried out. The principal test condition studied was that of the Iincar motion between two dry, clean, untnbricatcd, flat surfaces. This work indicated the existence of two modes of contact, one of pure sliding and a scv:ond of areas undergoing shear. The lowfriction, low-wear examples appear to be special cases wherein almost all contact areas XC’ of the first type. A theory of friction has been postulated, based principally an the analysis of these trsts. Friction Characteristics of Sliding Surfaces Undergoing Subsurface Plastic Flow. RIilton C. Shaw, Abraham Ber and Pierre A.
statistical-treatment mcthc&i arc includvtl. .2 mathematical expression relating thcst, variables to life expccta,ncy is prcstantcd and the optimization of th?sca vxriablrs is discussed.
Mamin. J. Haszc Eng. (Traces. _;I.SME, Ser. II). 82 (1960) 342-346. Tt is well known that the load of an ordinaryfriction slider is supported by a large number of surface asperities having a collective arca that is small compared with the apparent area of ContaCt. 1x1 many metalworking opcrations, such as wire drawing, extruding, rolling, and metal cutting, the bulk metal undergoes plastic deformations as sliding occurs. The influence of this subsurface flow upon the coefficient of sliding friction is discussed. Tyre-Road Friction : A New Approach. I). Tabor. The AtJew .%ir~zlist, 5 (1959) 13$1336; 4 figs. t high friction coefficient between tyrrt and road reduces the tcndencv to skid on wet snrfaces. Tread patterns & tyres and motlification of road suriaces are two approaches : experiments show that a third may bc to “build-in” a high friction into the tread material. Tire-to-surface Friction-coefficient Measurements with a C-123 B Airplane on Various Runway Surfaces. Richard H. Sawyer and Joseph J. Kolnick. h'AS.4 Technical Report R-20, 1959, 32 pp., CI’O price, $ 0.40. An investigation was conducted to obtain information on the tire-to-surface friction coefficients available in aircraft braking during the landing run. The tests were mad? with a C-rz3B airplane on both wet and dry concrete and bituminous pavements and on snow-covered and ice surfaces at speeds from I?- to 115 knots. itfcasurements were made of the maximum (incipient skidding) friction coefficient, the full-skidding (locked wheel) friction coefficient, and the wheel slip ratio during braking. Features of Slip Friction during the Movement of a Body over an Anisotropic Surface. (in Russian) A. U. Galeev and Yu. I. I’crsbits., Il‘rudi Moskou. Inst. In&. %A.-d. Tms$., gzll 1 (19.57) 16g-180. Ref. Z&r. Mekh., no. 1I (19.58) Rev. rzrj6. For Abstract see A#. Mechanics Rem., I3 (4) (1960) 308.
Some Recent Experiments on the Friction, Wear and Deformation of Solids. F. I’. Rowden. S.z4.I:. Trans., 67 (1959) Qjo658: ‘4 figs., I table, 9 refs. Experiments ha\-e been conducted at Cambridge IJniversitp which probed the sliding friction and wear of nonmetals, and the deformation of solids at high rates of strain. The author was particularly interested in the deformation and damage of metals and nonmetals under high-speed liquid impact. The findings will contribute to the development of materials that can withstand the friction of high-speed space flight. The author discusses the sliding friction and wear of wood, diamond, glass, rubber, and metallic carbides. In the last part of the paper, he describes the high-speed problems arising when solids are deformed very rapidly. Reviving the Classical Theory of Friction by aModern Dislocation Theory of Deformation Revision. John H. Dismant.J. AppZ. Phys., 31 (1960) 221 ; 4 refs. Letter to the Editor. Hypothesis about the influence of dislocations on work hardening of thin films under conditions of sliding friction. Author assumes essentially elastic forces to be operative in friction. (See also Thesis, Utah 19,j.j) Research ProgramonHighVacuum Friction. S. Hansen, WT. Jones and -4. Stephenson, Litton
~%d%StrieS
Of
&Z&f .,
~$UCt?
h%St?cWGh
J.abovafo&s did Refit. 2907, (1959) I48 pp. A twelve-month program directed towards the study of surface friction under conditions of high vacuum (IO--~ to ~0-6 mm Hg) has hrcn carried out. The principal test condition studied was that of the Iincar motion between two dry, clean, untnbricatcd, flat surfaces. This work indicated the existence of two modes of contact, one of pure sliding and a scv:ond of areas undergoing shear. The lowfriction, low-wear examples appear to be special cases wherein almost all contact areas XC’ of the first type. A theory of friction has been postulated, based principally an the analysis of these trsts. Friction Characteristics of Sliding Surfaces Undergoing Subsurface Plastic Flow. RIilton C. Shaw, Abraham Ber and Pierre A.
statistical-treatment mcthc&i arc includvtl. .2 mathematical expression relating thcst, variables to life expccta,ncy is prcstantcd and the optimization of th?sca vxriablrs is discussed.
Mamin. J. Haszc Eng. (Traces. _;I.SME, Ser. II). 82 (1960) 342-346. Tt is well known that the load of an ordinaryfriction slider is supported by a large number of surface asperities having a collective arca that is small compared with the apparent area of ContaCt. 1x1 many metalworking opcrations, such as wire drawing, extruding, rolling, and metal cutting, the bulk metal undergoes plastic deformations as sliding occurs. The influence of this subsurface flow upon the coefficient of sliding friction is discussed. Tyre-Road Friction : A New Approach. I). Tabor. The AtJew .%ir~zlist, 5 (1959) 13$1336; 4 figs. t high friction coefficient between tyrrt and road reduces the tcndencv to skid on wet snrfaces. Tread patterns & tyres and motlification of road suriaces are two approaches : experiments show that a third may bc to “build-in” a high friction into the tread material. Tire-to-surface Friction-coefficient Measurements with a C-123 B Airplane on Various Runway Surfaces. Richard H. Sawyer and Joseph J. Kolnick. h'AS.4 Technical Report R-20, 1959, 32 pp., CI’O price, $ 0.40. An investigation was conducted to obtain information on the tire-to-surface friction coefficients available in aircraft braking during the landing run. The tests were mad? with a C-rz3B airplane on both wet and dry concrete and bituminous pavements and on snow-covered and ice surfaces at speeds from I?- to 115 knots. itfcasurements were made of the maximum (incipient skidding) friction coefficient, the full-skidding (locked wheel) friction coefficient, and the wheel slip ratio during braking. Features of Slip Friction during the Movement of a Body over an Anisotropic Surface. (in Russian) A. U. Galeev and Yu. I. I’crsbits., Il‘rudi Moskou. Inst. In&. %A.-d. Tms$., gzll 1 (19.57) 16g-180. Ref. Z&r. Mekh., no. 1I (19.58) Rev. rzrj6. For Abstract see A#. Mechanics Rem., I3 (4) (1960) 308.