PPT of Journal TRIBOLOGICAL RESPONSE OF FRESH AND USED ENGINE OILS: THE EFFECT OF SURFACE TEXTURING, ROUGHNESS AND FUEL TYPE.

1. INDIAN INSTITUTE OF TECHNOLOGY (ISM),
DHANBAD
SEMINAR PRESENTATION ON
TRIBOLOGICAL RESPONSE OF FRESH AND USED
ENGINE OILS:
THE EFFECT OF SURFACE TEXTURING,
ROUGHNESS AND FUEL TYPE.
Presented by: Nagesh Dewangan
M.Tech. 1st Year, MET
Admn. No.:17MT001503

2. Introduction
 Internal Combustion Engines (ICEs) are significant source of friction.
 Engines are becoming more powerful due to improvement in oil formulation, surface
finishing and development of new materials but friction losses are still high 11.5%.
 Major part of friction occurs in bearing (60%) and remaining (40%) in cam, gear and
differential etc.
 Boundary Lubrication cause significant loss..
Fig 1: Specific film thickness and Speed vs stroke length

3. Literature Survey
 As in case of boundary lubrication, solid lubricants are used such as MoS2, PTFE, Carbon,
Diamond etc.
 Surface properties were used to evaluate the effect of surface roughness and texture on
MoS2 formation.
 MoS2 is dispersed in the oil as MoDTC.
 Formation of MoS2 requires nascent metal surfaces.
 Different lubricating oils were used for the experiment.

4. Literature Gap
 As simply using Base Oil tries to increase friction due to increase in plasticity.
 So, we have to add some material into it so as to reduce friction.
 Other oils such as gasoline and ethanol tries to reduce friction but its oxidation is
high.

5. Objective
 To find the best lubricant for the lubrication purpose.
 To evaluate the effect of new and used oil on engine lubrication.
 To find effect of surface texture on lubrication.

6. Method and Material
 Tribotests
 Oil analysis is done using an Optical Instrument (Ball on Disk arrangement).
 Test is carried out for 20min with 3ml of oil on the surface of disc.
 Temperature is about 40 OC with 35N of force.
 Reciprocating motion of 5mm stroke and 10Hz frequency.
Fig 2: Tribometer Ball on Disk

7. Method and Material
 Test Specimens
 Ball – AISI 52100 Bearing Steel, Disk – AISI H13 Tool Steel
 Smooth and Rough surface finishing of disk.
 2D profile within a Hertzian Contact Width (┴ and ═) on the lay.
 Tested Lubricants
 Base Oil, a Commercial engine oil (5W30-SM),
Used Oils (5W30E22 and 5W30E100).
 Main properties are Kinematic viscosity,
Plasticity Index, Specific film thickness, TAN,TBN.
 Oil is analysed using Atomic Emission Spectroscopy.

8. Results
 Lubrication and Contact Mechanics
 Hertzian Contact take place where maximum contact pressure for ideally smooth surface are
under surface hardness. PO=1.51GPa, H=6.42GPa.
 Oil Analysis
 SM generation oils are tested for fuel economy test.
 FEI is tested with reference oil (Base Oil).
Fig. 4. FTIR spectra of 5W30, 5W30E100, 5W30E22,
E100 and E22.
Fig. 3. Real area of contact vs. plasticity index.

9. Results
 Friction Coefficient Measurement
 COF vs Test Time at temperature 40 OC for smooth and rough surfaces.
Fig 5: Smooth surface: COF versus time Fig 6: Rough surface: COF versus time

10. Discussion
 Friction Response: Rough Surface
 Mechanism of friction mechanism depends primarily on the roughness geometry of the harder
material, which represents the mean asperity slope.
 Friction Response: Smooth Surface
 Adhesion component of friction increases as plasticity index decreases.
 Effect of Texture Direction on additive activation
 The higher asperity deformation allows for the removal of surface oxides.
 Oxide free surfaces, as stated before, have been indicated as a requirement to the reaction by which
MoDTC forms MoS2.

11. Conclusion
 For very low specific film thickness values(Λ⪡1) and high plasticity index (ψ⪢1)(rough surface),
the friction values depend on the harder body.
 Formation of MoS2 films were shown to be dependent on the sliding direction of anisotropic
surfaces; resulting in friction reduction of E 100%.
 Aged oils showed COF values similar to those obtained with base oil. This behavior is attributed
to MoDTC depletion or oxidation.
 Gasoline contaminated oils were more oxidized than the ones contaminated with ethanol.
 Scope
• There is no evidence of high copper and lower Fe and Al in 5W30E22.
• Reason for formation of MoS2.
• Hematite and Magnetite are found in 5W30E100 and Base oil.
• What is the effect of texture on MoS2 formation.

12. Reference
 Tiago Cousseau, Amilton Sinatora, Brazil ” Tribological response of
fresh and used engine oils: The effect of surface texturing, roughness
and fuel type” ,Tribology International, Volume 2016 (60–69).