Elastohydrodynamic lubrication (EHL) is an important branch of the lubrication theory, describing lubrication mechanisms in nonconformal contacts widely found in many mechanical components such as various gears, rolling bearings, cams and followers, metal-rolling tools, traction drives, and continuous variable transmissions. These components often transmit substantial power under heavy loading conditions. Also, the roughness of machined surfaces is usually of the same order of magnitude as, or greater than, the estimated average EHL film thickness. Consequently, most components operate in mixed lubrication regime with significant asperity contacts. Due to very high pressure concentrated in small areas, resulted from either heavy external loading or severe asperity contacts, or often a combination of both, subsurface stresses may exceed the material yield limit, causing considerable plastic deformation, which may not only permanently change the surface profiles and contact geometry but also alter material properties through work hardening as well. In the present study, a three-dimensional plasto-elastohydrodynamic lubrication (PEHL) model has been developed by taking into account plastic deformation and material work-hardening. The effects of surface/subsurface plastic deformation on lubricant film thickness, surface pressure distribution, and subsurface stress field have been investigated. This paper briefly describes the newly developed PEHL model and presents preliminary results and observed basic behavior of the PEHL in smooth-surface point contacts, in comparison with those from corresponding EHL solutions under the same conditions. The results indicate that plastic deformation may greatly affect contact and lubrication characteristics, resulting in significant reductions in lubricant film thickness, peak surface pressure and maximum subsurface stresses.

1.
Dowson
,
D.
, and
Higginson
,
G. R.
, 1966,
Elastohydrodynamic Lubrication
,
Pergamon
,
Oxford, UK
.
2.
Hamrock
,
B. J.
, and
Dowson
,
D.
, 1981,
Ball Bearing Lubrication: The Elastohydrodynamics of Elliptical Contacts
,
Wiley
,
New York
.
3.
Gohar
,
R.
, 2001,
Elastohydrodynamics
,
2nd ed.
,
Imperial College Press
,
London
.
4.
Hu
,
Y. Z.
, and
Zhu
,
D.
, 2000, “
A Full Numerical Solution to the Mixed Lubrication in Point Contacts
,”
ASME J. Tribol.
0742-4787,
122
(
1
), pp.
1
9
.
5.
Zhu
,
D.
, 2007, “
On Some Aspects in Numerical Solution of Thin-Film and Mixed EHL
,”
Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol.
1350-6501,
221
, pp.
561
579
.
6.
Xu
,
G.
,
Nickel
,
D. A.
,
Sadeghi
,
F.
, and
Ai
,
X. L.
, 1996, “
Elastoplastohydrodynamic Lubrication With Dent Effects
,”
Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol.
1350-6501,
210
, pp.
233
245
.
7.
Niu
,
R.
, and
Huang
,
P.
, 2006, “
The Influences of Elastic-Plastic Deformation of Rough Surfaces on Elastohydrodynamic Lubrication for Line Contacts
,”
Lubr. Eng.
0024-7154 (in Chinese),
6
, pp.
20
23
.
8.
Liu
,
S. B.
,
Wang
,
Q.
, and
Liu
,
G.
, 2000, “
A Versatile Method of Discrete Convolution and FFT (DC-FFT) for Contact Analyses
,”
Wear
0043-1648,
243
, pp.
101
111
.
9.
Jacq
,
C.
,
Nelias
,
D.
,
Lormand
,
G.
, and
Girodin
,
D.
, 2002, “
Development of a Three-Dimensional Semi-Analytical Elastic-Plastic Contact Code
,”
ASME J. Tribol.
0742-4787,
124
, pp.
653
667
.
10.
Wang
,
F.
, and
Keer
,
L. M.
, 2005, “
Numerical Simulation for Three Dimensional Elastic-Plastic Contact With Hardening Behavior
,”
ASME J. Tribol.
0742-4787,
127
, pp.
494
502
.
11.
Boucly
,
V.
,
Nelias
,
D.
, and
Green
,
I.
, 2007, “
Modeling of the Rolling and Sliding Contact Between Two Asperities
,”
ASME J. Tribol.
0742-4787,
129
, pp.
235
245
.
12.
Nélias
,
D.
,
Antaluca
,
E.
,
Boucly
,
V.
, and
Cretu
,
S.
, 2007, “
A Three-Dimensional Semianalytical Model for Elastic-Plastic Sliding Contacts
,”
ASME J. Tribol.
0742-4787,
129
, pp.
761
771
.
13.
Chen
,
W. W.
,
Liu
,
S. B.
, and
Wang
,
Q.
, 2008, “
Fast Fourier Transform Based Numerical Methods for Elasto-Plastic Contacts With Nominally Flat Surface
,”
ASME J. Appl. Mech.
0021-8936,
75
, p.
011022
.
14.
Chen
,
W. W.
, and
Wang
,
Q.
, 2008, “
Thermomechanical Analysis of Elasto-Plastic Bodies in a Sliding Spherical Contact and the Effects of Sliding Speed, Heat Partition, and Thermal Softening
,”
ASME J. Tribol.
0742-4787,
130
, p.
041402
.
15.
Zhu
,
D.
, and
Hu
,
Y. Z.
, 1999, “
The Study of Transition From Full Film Elastohydrodynamic to Mixed and Boundary Lubrication
,”
The Advancing Frontier of Engineering Tribology
,
Proceedings of the 1999 STLE/ASME H. S. Cheng Tribology Surveillance
, pp.
150
156
.
16.
Wang
,
W. Z.
,
Wang
,
H.
,
Liu
,
Y. C.
,
Hu
,
Y. Z.
, and
Zhu
,
D.
, 2003, “
A Comparative Study of the Methods for Calculation of Surface Elastic Deformation
,”
Proc. Inst. Mech. Eng., Part J: J. Eng. Tribol.
1350-6501,
217
, pp.
145
154
.
17.
Liu
,
Y. C.
,
Wang
,
Q.
,
Wang
,
W. Z.
,
Hu
,
Y. Z.
, and
Zhu
,
D.
, 2006, “
Effects of Differential Scheme and Mesh Density on EHL Film Thickness in Point Contacts
,”
ASME J. Tribol.
0742-4787,
128
, pp.
641
653
.
18.
Ren
,
N.
, 2009, “
Advanced Modeling of Mixed Lubrication and Its Mechanical and Biomedical Applications
,” Ph.D. thesis, Northwestern University, Evanston, IL.
19.
Jackson
,
R. L.
, and
Green
,
I.
, 2005, “
A Finite Element Study of Elasto-Plastic Hemispherical Contact Against a Rigid Flat
,”
ASME J. Tribol.
0742-4787,
127
, pp.
343
354
.
20.
Johnson
,
K. L.
, 1985,
Contact Mechanics
,
Cambridge University Press
,
Cambridge, UK
.
21.
Hardy
,
C.
,
Baronett
,
C. N.
, and
Tordion
,
G. V.
, 1971, “
The Elasto-Plastic Indentation of a Half-Space by a Rigid Sphere
,”
Int. J. Numer. Methods Eng.
0029-5981,
3
, pp.
451
462
.
22.
Kral
,
E. R.
,
Komvopuolos
,
K.
, and
Bogy
,
D. B.
, 1993, “
Elastic-Plastic Finite Element Analysis of Repeated Indentation of Half-Space by a Rigid Sphere
,”
ASME J. Appl. Mech.
0021-8936,
60
, pp.
829
841
.
23.
Chen
,
W. W.
,
Wang
,
Q.
,
Liu
,
Y. C.
,
Chen
,
W.
,
Cao
,
J.
,
Xia
,
C.
,
Talwar
,
R.
, and
Lederich
,
R.
, 2007, “
Analysis and Convenient Formulas for Elasto-Plastic Contacts of Nominally Flat Surfaces: Average Gap, Contact Area Ratio, and Plastically Deformed Volume
,”
Tribol. Lett.
1023-8883,
28
, pp.
27
38
.
You do not currently have access to this content.