Forces and deformations of lead films in frictional processes

Forces and deformations of lead films in frictional processes

LITERATURE AND CURRENT EVENTS Ind. Eng. Chew., Prod. Res. Develop., (1965) 86-92; 3 figs., 5 tables, 16 refs. 241 4 (2) A surface chemical approa...

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LITERATURE

AND CURRENT

EVENTS

Ind. Eng. Chew., Prod. Res. Develop., (1965) 86-92; 3 figs., 5 tables, 16 refs.

241 4 (2)

A surface chemical approach to the reduction of boundary friction in solid polymers is described. Dry frictional properties of several classes of polymeric solids have been reduced significantly by the addition of small proportions of a suitably designed surface-active compound. Appropriate fluorocarbon derivatives have been prepared and found effective in poly(methy1 methacrylate), poly(viny1 chloride), and several poly(vinylidene chloride) copolymers. These addition agents are effective in both polymer films prepared by evaporation from a solvent and thick disks prepared from the melt. The low-energy surfaces formed by the fluorinated additives may also be self-healing - that is, any surface-active molecule lost from the film may be replaced by the diffusion of additional material to the interface. The decrease in friction caused by the addition agent is accompanied by an increase in the equilibrium contact angle of each of several liquids on the polymer surface. The small proportion of addition agent used caused only a small decrease in the hardness of the polymers. Various promising classes of applications are outlined. A Method for the Determination of the Coefficient of Friction of Metals under Conditions of Bulk Plastic Deformation. A. T. Male and M. G. Cockcroft, J. Inst. Metals, 93 (2) (1964) 38. Forces and Deformations of Lead Films in Frictional Processes, R. A. Burton and J. A. Russell, Lubrication Eng., zr (6) (1965) 227-233; II figs., 6 refs. Sliding friction and track width measurements are reported for a hemispherical steel rider on a lead disk, and on 0.005 mm thick lead films electroplated onto tool-steel substrates. Flow pressure, junction shear strength, and plowing resistance are computed from the data for lubricated and unlubricated sliding at 25°C. and for unlubricated sliding at -rg5”C. These computed values are discussed relative to a simple theoretical model, and it is shown how they relate to bulk properties of the lead.

(1964)

the Variational

For abstract (w%)

31 E). see Appl.

I

Mech.

(1964) Rev.,

43-46

18

(II)

949.

Squeeze Film Pressures. W. A. Wolfe, Appl. Sci. Res., Ser. A, 14 (I/Z) (r964/65) 77-90. For abstract see Appl. Mech. Rev., 18 (II) (I965)

94%

A Wedge-flow Approach to Lubrication Theory. W. E. Langlois, Quart. Appl. Math., 23 (I) (1965) 39-46. For abstract see Appl. Mech. Rev., 18 (II) (w65)

948.

Hydrodynamic Lubrication of an Externally-pressurized Beating Using a ReinerRivlin Fluid as Lubricant. R. C. Srivastava, Appl. Sci. Res., Ser. A, 14 (I/2) (Ig64/65)

For abstract (19%)

133-137.

see Appl.

Mech.

Rev.,

18

(II)

948.

Lubrication, Corrosion and Wear. (A continuing bibliography.) NASA SP-7020, 1965. Available from the Clearinghouse for Federal Scientific and Technical Information (CFSTI), Springfield, Va. 22151; price: $ 1.75. A selection of annotated references to unclassified reports and journal articles introduced into the NASA information system during the period January, 1962 to March, 1965.

AND

A General View of Metal-working Lubcication. L. B. Sargent Jr., Lubrication Eng., ZI (7) (1965) 282-286; 4 figs., I table, II refs.

LUBRIGNTS

3. I. Lubrication On

ASME,

Dynamic

161-169.

For abstract see Appl. Mech. Rev., 18 (IO) (1965) 865; see also Wear, 3 (1960) 26, 473.

3. LUBRICATION

(Trans.

Gas

Lubrication in Space. (Schmierung unter Weltraumbedingungen ; a survey in German.) G. Spengler and F. Wunsch, Deut. LuftRaumfahrt Mitt. 65-07, 1965, I 18 pp. ; 54 figs., IO tables, rg5 refs. To be purchased from: Zentralstelle fur Luftfahrtdokumentation und -information (ZLDI), Mfinchen 27, Maria-Theresia-Strasse 21; price: DM 36.90. Operation of equipment in space vehicles has created new requirements of lubricants. The lubricants are subject to additional influences, such as zero gravity, meteorities, various forms of radiation energy, temperature extremes, and ultrahigh vacuum. The paper critically reviews the literature on the development and testing of suitable lubricants.

A Study of the Microtopography of a Friction Technique J. D. Huffington, Proc. Roy. Sot. London, Ser. A, 279 (1377)

Equations in Studies of Lubrication. L. N. Tao, J. Appl. Mech.,

3.2. Lubricants Principle

and Lagrange

Emproved

Ceramic-bonded

Wear,

Calcium 9

Fluor-

(1966) 239-247