a presentation on advances in tribology

1. SEMINAR ON
ADVANCES IN TRIBOLOGY
BY
APURV VERMA
3RB09ME011
DEPARTMENT OF MECHANICAL ENGINEERING
BHEEMANNA KHANDRE INSTITUTE OF TECHNOLOGY, BHALKI

2. INDEX
• INRTODUCTION
• PRACTICAL OBJECTIVES OF TRIBOLOGY
• FRICTION
• TYPES OF MOTION
• TRIBOLOGY IN PISTON RINGS AND CYLINDER LINER
• WEAR AND ITS MECHANISM
• LUBRICATION
• SOYBEAN OIL AS FUTURE LUBRICANT OIL FOR IC ENGINES
• PVD
• TRIBOLOGY CONCERNS IN MEMS DEVICES
• IMPACT OF TRIBOLOGY
• ECONOMIC ASPECTS OF TRIBOLOGY

3. INTRODUCTION
• It is a GREEK word TRIBOS means rubbing processes.
• Tribology is the science and technology of interacting surfaces in
relative motion.
• Tribology tries to describe everything that happens when things
rub together.
TRIBOLOGY TRIANGLE

4. PRACTICAL OBJECTIVES OF
TRIBOLOGY

5. FRICTION
• What is friction?
 It’s a FORCE.
 Occurs whenever two objects are IN CONTACT with each other.
 It’s the resistance to movement. It SLOWS objects down.
5

6. Fto move the box on:
Let’s use THE SAME FORCE
RICTION
higher friction
wooden floor
lower friction
ice
In which case friction is higher?
Which one will slide further?
WHY?
6

7. LUBRICATION
Why do we need it?
 lower the friction
 prevent wear
↓ wear
↓ friction remove heat and contamination

8. WEAR
 What is wear?
It’s the removal of material
from a solid surface by the
action of another surface.
8

9. WEAR MECHANISMS
• Abrasive
• Adhesive
– High contact pressures
– Low contact pressures
– Wear tracks
– Augmented asperities

10. TYPES OF MOTION
There are two types of motion between two
moving parts.
● Sliding motion
e.g :- Piston in IC engine
●Rolling motion
e.g :- Bearings, wheels of automobiles

11. TRIBOLOGY IN PISTON RINGS AND
CYLINDER LINER
• Cylinder liner is fixed one
and piston will slide up
and down inside on it.
• Friction exists between
these parts , it results in
wear.
• It can be reduced by applying
lubricant.

12. RECENT DEVELOPMENTS IN
TRIBOLOGY
• Soybean oil as future lubricant for IC engines.
• Chemical Vapor Deposition (CVD)
• Physical Vapor Deposition (PVD)
• Tribology concerns in MEMS devices
Diamond Coating
Ultrananocrystalline diamond (UNCD)
Self Assembled Monolayers (SAMs)
Cantilever Beam Array Technique

13. SOYBEAN OIL AS FUTURE LUBRICANT
FOR IC ENGINES
• Soybean oil is a vegetable oil
extracted from soybean seeds.
• It is easily available at low
price.
PROPERTIES OF SOYBEAN OIL :-
> It has a high viscosity index up to 223.
> Has comparatively high flash point 610°F.
> Has good fire point about 650°F.
> It has high pour point, it can be reduced by winterizing the
soybean oil.

14. MERITS OF SOYBEAN OIL
• Soybean oil is biodegradable, in general it is
less toxic.
• It is a renewable oil, so it reduces dependency
of foreign petroleum products.
• Ease of processing.

15. CHEMICAL VAPOUR DEPOSITION
CVD is used to grow a thin layer of advanced
materials on the surface of a substrate.
Application:-
• Integrated circuits, electronic devices and sensors.
• Catalysts
• Micromachines, fine powder and ceramic powder
protective coatings.

16. CHEMICAL VAPOUR DEPOSITION
Thin film is formed from gas phase
components.

17. CHEMICAL VAPOUR DEPOSITION
• Two types of CVD:-
• LPCVD (Low Pressure CVD ) :- Good
uniformity, Used for poly-Si, oxide, nitride.
• PECVD (Plasma Enhanced CVD ) :- Low
temperature process and high deposition rate.
Used for oxide, nitride, etc.

18. CHEMICAL VAPOUR DEPOSITION
Pressure sensor Resistance-heated furnace
Quartz tube
Trap
To exhaust
Si Wafers
Pump
Source
gases
Gas control
system
LPCVD Systems

19. PHYSICAL VAPOUR DEPOSITION
• PVD is a fundamentally a vaporization coating technique,
involving transfer of material on an atomic level.
• It is an alternative process to electroplating.
• The process is similar to chemical vapor deposition (CVD)
except for the raw materials.
• i.e. the material that is to be deposited starts in solid form,
whereas in CVD the precursors are introduced to the reaction
chamber in gaseous state.

21. APPLICATIONS OF PVD
• PVD coatings are used to improve
Hardness, Wear Resistance, Oxidation
Resistance.
Thus, such coatings used in variety of applications
such as :-
• Aerospace
• Automotive
• Surgical/medical
• Dies and moulds for all manner of material processing
• Cutting tools
• Fire arms

22. TRIBOLOGY CONCERNS IN MEMS
DEVICES
• Friction and Wear are the biggest issues
in blocking advances of MEMS
technology.
• Once SAMS and Diamond Coatings are
more fully developed, MEMS technology
will be able to more completely realize its
potential.

23. DIAMOND COATINGS
• Diamond has a variety of useful properties compared to
Silicon
– Low wear, low coefficient of friction, thermally
stable, isotropic hardness
• Diamond cannot be simply made into smaller and
smaller flakes, then deposited on MEMS devices
• Diamond (or diamond-like) film must be grown on
surface.

24. UNCD
ULTRANANOCRYSTALLINE DIAMOND
• A “better” method for producing diamond-like films.
Grain size is 2-5nm.
• Unlike conventional diamond film CVD, C60 is
introduced into the reaction along with CH4.
– C60 collides with itself, creating C2 (carbon “dimers”)
– These C2 molecules enter the diamond lattice.
– An abundance of C2 is the goal of the UNCD creation
process.

25. SELF ASSEMBLED
MONOLAYERS (SAMs)
• Two Types
• Silane – deposits on silicon
• Thiol – deposits on gold
• Deposition Formations Deposition
• Densely Packed O O O
• Amorphous Structure Si Si Si Si
• Functional group determines: OH OH OH OH O O O O
Si Si Si Si Si Si Si Si
• applications O O O O O O O O
• hydrophilicity/hydrophobicity
• Used as:
• binders for subsequent molecules
• lubricants
• Common hydrophobic SAMS:
• OTS (long chain hydrocarbon)
• FDTS (long chain fluorocarbon)

26. CANTILEVER BEAM ARRAY
TECHNIQUE
• Cantilever beams are fabricated of Beam Structures
different lengths
• Cantilevers are put into contact with
surface
• Longer beams adhere to surface
• Longest beam that does not stick
signifies adhesion force
• SAM coated beams adhere after
longer lengths than oxide surface

27. ECONOMIC ASPECTS OF TRIBOLOGY
• The LUBRICANT REPORT estimated an amount exceeding
500 million pounds can be saved in the civilian sector of
UK by research in tribology.
• The estimated 11 % total savings in annual US energy
consumption is equivalent to some 16 billion US dollars
by an expenditure in research and development o f an
estimated twenty-four million dollars.
• Analysis of the failure of boiler tubes indicate that about
one-third of all occurrences were due to erosion.
• In UK, the application of tribological principles can effect
national energy savings. These are estimated at 468 to
700 million pounds per annum.

28. IMPACT OF TRIBOLOGY
• Since the publication of the Lubrication Report there has been
an increasing awareness throughout industry of the subject of
tribology.
• In the UK the National Centre for Tribology and Industrial
Units of Tribology have been set up to provide advice t o
industry on the utilisation of existing knowledge.
• Tribology is now recognized universally and President Carter
of U.S.A. declared it to be a generic technology underlying
many industrial sections and the prospectus for an Industrial
Tribology Institute at Rensselaer Technology Center has been
presented.

29. REFERENCES
• Mr. RAJSHEKHAR MATHAPATI
• www.wikipedia.com
• www.slideshare.com
• www.google.com
• Tribology In Industries by SUSHIL KUMAR
• Engineering Tribology by G.W. STACHOWIAK
• Industrial Tribology by M.H. JONES

30. ANY QUERIES