TRIBOLOGI TKM4094
PRINSIP DASAR TRIBOLOGI
Dosen Pengampu
Khairul Anam, ST., MSc.
Laboratorium Sentral Mesin, Gedung Mesin I, Lantai I Jl. MT Haryono No. 167, Malang 65145
No. HP : +6281336327969
Email : k_anari27@yahoo.com
anamesin.lecture.ub.ac.id
Tujuan
Memberikan pemahaman tentang gesekan, aus dan pelumasan serta pengaruhnya dalam
komponen mesin.
Pokok Bahasan
Prinsip dasar tribologi Gesekan
Aus
Pelumasan
Tribologi pada kontak dengan kinematika rendah
Tribologi pada kontak dengan kinematika tinggi
Efisiensi pelumasan
Referensi
Introduction to Tribology_Bharat Bhushan
Tribology in Machine Design_TA Stolarski
Penilaian
Kehadiran 10%
Quiz 25%
Tugas 25%
UAS 40%
HP WAJIB DI SILENT ATAU DI NON-AKTIFKAN!
Tribologi
• When
• Where
• Result
• Analysis
• Object
• Who
• Object
• Who
What Why
How
How many/
How
much
Prinsip dasar tribologi
Tribologi dikenalkan pertama kali oleh Jost (1966)
Tribologi berasal dari bahasa yunani “TRIBOS” yang berarti
“BERGESEKAN”
Tribologi adalah cabang ilmu desain mesin (friction, wear
dan lubrication)
Prinsip dasar tribologi
Prinsip dasar tribologi
Elemen mesin yang harus mempertimbangkan tribologi
◦ Bantalan luncur
Prinsip dasar tribologi
◦ Bantalan gelinding Piston
Prinsip dasar tribologi
◦ Cam Friction Drive
Prinsip dasar tribologi
◦ Roda Gigi
Prinsip dasar tribologi
◦ Rem
◦ Kopling
◦ Mur-Baut
◦ Seal
◦ Semir
◦ Menulis
◦ Berjalan
Prinsip dasar tribologi
Koefisien Gesek dan Keausan
◦ Struktur (properti material)
◦ Kondisi saat mesin bekerja (beban, temperature, waktu, dan lain-lain)
◦ Interaksi antar komponen
Prinsip dasar tribologi
Gaya Gesek (tanpa pelumasan)
◦ Gaya gesek selalu berlawanan arah dengan perpindahan
◦ F = fW
Dimana: F = Gaya Gesek
f = Koefisien Gesek W = Gaya Normal
◦ Gaya gesek tidak tergantung pada luas kontak
The Nature of Surface
Chemical Reaction
The nature of Surface
Surface Texture
Macro Micro
Kekasaran Permukaan
American National Standards Institute (ANSI)
International
Standardization
Organization (ISO)
The Future of
Tribology
P RACTICAL O BJECTIVES O F
T RIBOLOGY
FRICTION
TRIBOLOGY TRIANGLE
F RICTION
What is friction?
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It’s a FORCE.
Occurs whenever two objects are IN CONTACT with each other.
It’s the resistance to movement. It SLOWS objects down.
higher friction
lower friction
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F RICTION
Let’s use THE SAME FORCE to move the box on:
wooden floor
ice
Which one will slide further?
In which case friction is higher? WHY?
L UBRICATION
Why do we need it?
↓ friction
↓ wear
remove heat and contamination
lower the friction
prevent wear
W EAR
What is wear?
It’s the removal of material from a solid surface by the action of another surface.
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W EAR M ECHANISMS
Adhesive
◦ Low contact pressures
◦ Augmented asperities
Abrasive
◦ High contact pressures
◦ Wear tracks
T YPES O F M OTION
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
T RIBOLOGY I N P ISTON R INGS A ND C YLINDER L INER
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.
R ECENT D EVELOPMENTS I N T RIBOLOGY
Soybean oil as future lubricant for IC engines.
Chemical Vapor Deposition (CVD) Physical Vapor Deposition (PVD)
S OYBEAN O IL A S F UTURE
LUBRICANT F OR IC E NGINES
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.
A DVANTAGES O F S OYBEAN O IL
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.
C HEMICAL V APOUR D EPOSITION
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.
C HEMICAL V APOUR D EPOSITION
Thin film is formed from gas phase
components.
C HEMICAL V APOUR D EPOSITION
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.
C HEMICAL V APOUR D EPOSITION
Si Wafers
Quartz tube Resistance-heated furnace Pressure sensor
Gas control
Source gases
Pump Trap
exhaust To
system
LPCVD Systems
P HYSICAL V APOUR D EPOSITION
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.
A PPLICATIONS O F 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
E CONOMIC A SPECTS O F T RIBOLOGY
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.
I MPACT O F T RIBOLOGY
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
