The friction characteristics of the lubricated rough surfaces are of great significance for the lubrication design of mechanical structures. To study the behaviour of friction coefficient in the rolling-sliding coexisting line contact rough surfaces under mixed lubrication regime, the Kogut-Etsion elastic-plastic model and the Carreau rheological model are utilized to describe the dry rough contact and the non-Newtonian characteristics of the lubricant film, respectively. A mixed lubrication model for predicting friction coefficient is proposed based on the load-sharing concept at which the normal load is shared by the lubricant film and the asperity component. The effects of normal load, surface roughness and lubricant inlet viscosity on hydrodynamic scaling factor, film thickness parameter and the coefficient of friction were analyzed. The dimensionless predictive expression for the critical sliding velocity is derived by nonlinear regression. The research results provide theoretical guidance for the lubrication design and optimization of mechanical structures.
AzushimaANakataYToriumiT. Prediction of effect of rolling speed on coefficient of friction in hot sheet rolling of steel using sliding rolling tribo-simulator. J Mater Process Technol2010; 210: 110–115.
2.
BakoglidisKDNedelcuIIvanovIG, et al.Rolling performance of carbon nitride-coated bearing components in different lubrication regimes. Tribol Int2017; 114: 141–151.
3.
HanLZhangD-WWangF-J. Predicting film parameter and friction coefficient for helical gears considering surface roughness and load variation. Tribol Trans2013; 56: 49–57.
4.
QiaoGLiuGMaS,et al.Thermal characteristics analysis and experimental study of the planetary roller screw mechanism. Appl Therm Eng2019; 149: 1345–1358.
5.
XiaoHSunYXuJ. Investigation into the normal contact stiffness of rough surface in line contact mixed elastohydrodynamic lubrication. Tribol Trans2018; 61: 742–753.
6.
GreenwoodJAWilliamsonJP. Contact of nominally flat surfaces, proceedings of the royal society of London. Math Phys Sci A1966; 295: 300–319.
7.
ChangWREtsionIBogyDB. An elastic-plastic model for the contact of rough surfaces. J Tribol1987; 109: 257–263.
KogutLEtsionI. A finite element based elastic-plastic model for the contact of rough surfaces. Tribol Trans2003; 46: 383–390.
10.
ZhaoYWMaiettaDMChangL. An asperity microcontact model incorporating the transition from elastic deformation to fully plastic flow. J Tribol2000; 122: 86–93.
HamrockBJPanP. Simple formulas for performance parameters used in elastohydrodynamically lubricated line contacts. Trans ASME J Tribol1989; 111: 246–251.
13.
MoesH. Optimum similarity analysis with applications to elastohydrodynamic lubrication. Wear1992; 159: 57–66.
14.
JohnsonKLGreenwoodJAPoonSY. A simple theory of asperity contact in elastohydro-dynamic lubrication. Wear1972; 19: 91–108.
15.
GelinckESchipperDJ. Calculation of Stribeck curves for line contacts. Tribol Int2000; 33: 175–181.
16.
AkchurinABosmanRLugtPM,et al.On a model for the prediction of the friction coefficient in mixed lubrication based on a load-sharing concept with measured surface roughness. Tribol Lett2015; 59: 19.
17.
LinjamaaALehtovaaraALarssonR,et al.Modelling and analysis of elastic and thermal deformations of a hybrid journal bearing. Tribol Int2018; 118: 451–457.
18.
FaraonICSchipperDJ. Stribeck curve for starved line contacts. J Tribol2007; 129: 181–187.
19.
HeTWangJWangZ,et al.Simulation of plasto-elastohydrodynamic lubrication in line contacts of infinite and finite length. J Tribol2015; 137: 041505.
20.
JacksonRLGreenI. The behavior of thrust washer bearings considering mixed lubrication and asperity contact. Tribol Trans2006; 49: 233–247.
21.
GuoYLuXLiW,et al.A mixed-lubrication model considering elastoplastic contact for a piston ring and application to a ring pack. Proc Inst Mech Eng D J Automob Eng2015; 229: 174–188.
22.
MasjediMKhonsariMM. Film thickness and asperity load formulas for line-contact elastohydrodynamic lubrication with provision for surface roughness. J Tribol2012; 134: 011503.
23.
MasjediMKhonsariMM. Mixed elastohydrodynamic lubrication line-contact formulas with different surface patterns. Proc Inst Mech Eng J J Eng Tribol2014; 228: 849–859.
24.
NiuRJHuangP. The influences of elastic-plastic deformation of rough surfaces on elastohydrodynamic lubrication for line contacts. Lubr Eng2006; 6: 20–23.
25.
ZhuDWangJXWangQJ. On the stribeck curves for lubricated counterformal contacts of rough surfaces. J Tribol2015; 137: 021501.
26.
AllmaierHSanderDEPriebschHH,et al.Non-Newtonian and running-in wear effects in journal bearings operating under mixed lubrication. Proc Inst Mech Eng J J Eng Tribol2016; 230: 135–142.
27.
ChongWWFHamdanSHWongKJ,et al.Modelling transitions in regimes of lubrication for rough surface contact. Lubricants2019; 7: 77.
28.
CarreauPJ. Rheological equations from molecular network theories. Trans Soc Rheol1972; 16: 99–127.
29.
BairS. Shear thinning correction for rolling/sliding elastohydrodynamic film thickness. Proc Inst Mech Eng J J Eng Tribol2005; 219: 69–74.
30.
JangJYKhonsariMMBairS. On the elastohydrodynamic analysis of shear-thinning fluids. Proc R Soc A Math Phys Eng Sci2007; 463: 3271–3290.
31.
LiuYWangQJBairS,et al.A quantitative solution for the full shear-thinning EHL point contact problem including traction. Tribol Lett2007; 28: 171–181.
32.
KhonsariMMHuaDY. Thermal elastohydrodynamic analysis using a generalized non-Newtonian formulation with application to bair-winer constitutive equation. J Tribol1994; 116: 37–46.
33.
AkbarzadehSKhonsariMM. Performance of spur gears considering surface roughness and shear thinning lubricant. J Tribol2008; 130: 021503.
34.
Echávarri OteroJde la Guerra OchoaEChacón TanarroE,et al.Analytical model for predicting friction in line contacts. Lubr Sci2016; 28: 189–205.
35.
CarliMSharifKJCiulliE,et al.Thermal point contact EHL analysis of rolling/sliding contacts with experimental comparison showing anomalous film shapes. Tribol Int2009; 42: 517–525.
36.
GuptaPKChengHSZhuD,et al.Viscoelastic effects in MIL-L-7808-type lubricant, part I: analytical formulation. Tribol Trans1992; 35: 269–274.
37.
BeheshtiAKhonsariMM. Asperity micro-contact models as applied to the deformation of rough line contact. Tribol Int2012; 52: 61–74.
38.
BeheshtiAKhonsariM. An engineering approach for the prediction of wear in mixed lubricated contacts. Wear2013; 308: 121–131.
39.
LuXKhonsariMMGelinckER. The Stribeck curve: experimental results and theoretical prediction. J Tribol2006; 128: 789–794.
40.
HamrockBJ. Fundamentals of fluid film lubrication. New York: McGraw-Hill Education, 1994.
