An experimental investigation is presented to evaluate recently published models for the contact and sliding inception of a deformable sphere loaded against a smooth rigid flat. The effects of the normal load on the contact area, junction growth, and the static friction force in the elastic–plastic contact regime are presented. Very good correlation is found between the predicted and measured contact area. A dramatic decrease of the static friction coefficient with increasing normal loading is observed, similar to the trend predicted by the model. The quantitative agreement is, however, less satisfying. Some possible reasons for the poor agreement are pointed out.

1.
Liu
,
G.
,
Wang
,
Q. J.
, and
Lin
,
C.
,
1999
, “
A Survey of Current Models for Simulating the Contact between Rough Surfaces
,”
Tribol. Trans.
,
42
, pp.
581
591
.
2.
Greenwood
,
J. A.
, and
Williamson
,
J. B. P.
,
1966
, “
Contact of Nominally Flat Surfaces
,”
Proc. R. Soc. London, Ser. A
,
295
, pp.
300
319
.
3.
Pullen
,
J.
, and
Williamson
,
J. B. P.
,
1972
, “
On the Plastic Contact of Rough Surfaces
,”
Proc. R. Soc. London, Ser. A
,
327
, pp.
159
173
.
4.
Chang
,
W. R.
,
Etsion
,
I.
, and
Bogy
,
D. B.
,
1987
, “
Elastic Plastic Model for the Contact of Rough Surfaces
,”
ASME J. Tribol.
,
109
, pp.
257
262
.
5.
Chang
,
W. R.
,
Etsion
,
I.
, and
Bogy
,
D. B.
,
1988
, “
Static Friction Coefficient Model Metallic Rough Surfaces
,”
ASME J. Tribol.
,
110
, pp.
57
63
.
6.
Kogut
,
L.
, and
Etsion
,
I.
,
2002
, “
Elastic–Plastic Contact Analysis of a Sphere and a Rigid Flat
,”
ASME J. Appl. Mech.
,
69
, pp.
657
662
.
7.
Kogut
,
L.
, and
Etsion
,
I.
,
2003
, “
A Semi-Analytical Solution for the Sliding Inception of a Spherical Contact
,”
ASME J. Tribol.
,
125
, pp.
499
506
.
8.
Xie
,
W.
,
De Meter
,
E. C.
, and
Trethewey
,
M. W.
,
2000
, “
An Experimental Evaluation of Coefficients of Static Friction of Common Workpiece-Fixture Element Pairs
,”
Int. J. Mach. Tools Manuf.
,
40
, pp.
467
488
.
9.
Liu
,
Z.
,
Neville
,
A.
, and
Reuben
,
R. L.
,
2002
, “
The Effect of Film Thickness on Initial Friction of Elastic–Plastically Rough Surface With a Soft Thin Metallic Film
,”
ASME J. Tribol.
,
124
, pp.
627
636
.
10.
Johnson
,
K. L.
,
2000
, “
The Contribution of Micro/Nano-Tribology to the Interpretation of Dry Friction
,”
Proc. Inst. Mech. Eng., Part C: Mech. Eng. Sci.
,
214
, pp.
11
22
.
11.
Tabor
,
D.
,
1959
, “
Junction Growth in Metallic Friction: The Roll of Combined Stresses and Surface Contamination
,”
Proc. R. Soc. London, Ser. A
,
251
, pp.
378
393
.
12.
Courtney-Pratt
,
J. S.
, and
Eisner
,
E.
,
1957
, “
The Effect of Tangential Force on the Contact of Metallic Bodies
,”
Proc. R. Soc. London, Ser. A
,
238
, pp.
529
550
.
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