1. Tribology Course Seminar Course: Machine Design II By: Kavya M Bhat
Devender Jain
Deepak T
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11/17/2018

2. Contents Introduction History Need for tribology Wear Friction
Lubrication
Tribometer
Conclusion
References
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11/17/2018

3. Tribology
It is derived from the Greek word “tribo” which means rubbing or sliding.
Tribology is the science and engineering of interacting surfaces in relative motion. It includes the study and application of the principles of friction, lubrication and wear.
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11/17/2018

4. History
The term Tribology was coined, in 1966, by Professor Peter Jost and the working party which had been set up by the UK government of the day, to address the steep increase in machinery failures from wear and associated causes which resulted in heavy financial losses.
The purpose of the working party was to “investigate the present state of lubrication education and research in this country and to give an opinion on the needs of industry thereof”.
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11/17/2018

5. using the correct lubricant
The main conclusion of the Jost Committee, as it is now widely referred to, was that significant financial savings were achievable by the correct application of Tribology. Fairly simple actions such as:-
using the correct lubricant
servicing machines in a timely fashion and in accordance with the machine manufacturer’s instructions
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11/17/2018

6. Need for Tribology To minimize and eliminate losses.
Greater efficiency, performance, fewer breakdowns & savings.
Study various losses and analysis of losses.
Reduce losses by introducing a layer of lubrication.
Atomic and molecular observations on sliding surfaces.
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11/17/2018

7. Wear
In materials science, wear is erosion or sideways displacement of material from its "derivative" and original position on a solid surface performed by the action of another surface.
Wear is related to interactions between surfaces and more specifically the removal and deformation of material on a surface as a result of mechanical action of the opposite surface
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8. Types of Wear
Abrasion wear- when a hard rough surface slides over a softer surface.
Adhesive wear- be found between surfaces during frictional contact
Cavitation wear- caused by the localized impact of fluid against a surface or fast flowing fluids.
Erosion wear- the impact of particles of solid or liquid against the surface of an object.
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9. Wear can be minimized by modifying the surface properties of solids by one or more of "surface engineering" processes (also called surface finishing) or by use of lubricants (for frictional or adhesive wear).
Engineered surfaces extend the working life of both original and recycled and resurfaced equipments, thus saving large sums of money and leading to conservation of material, energy and the environment. Methodologies to minimize wear include systematic approaches to diagnose the wear and to prescribe appropriate solutions.
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10. Important methods include: Terotechnology
Horst Czichos's systems approach.
Nano-tribology
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11. Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
Types:
Dry friction
Fluid friction
Lubricated friction
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11/17/2018

12. Lubrication
Thin layers of gas, liquid and solid interposed between two surface is called lubrication.
Layers of material separate contacting solid bodies.
Main aim of lubrication is to reduce the wear and friction.
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13. Types of lubrication
Hydrodynamic lubrication- Analysis of Gaseous or liquid films is usually termed
Solid lubrication- Lubrication by solids is termed, Ex. Graphite
Elastohydrodynamic lubrication- Physical interaction between the contacting Bodies and the liquid lubricant.
Hydrostatic lubrication- Complete separation of sliding surfaces with negligible wear and very low friction. Applied to aerostatic and hybrid bearings.
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14. Tribometer
A tribometer is an instrument that measures tribological quantities, such as coefficient of friction, friction force, and wear volume, between two surfaces in contact. It was invented by the 18th century Dutch scientist Musschenbroek
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11/17/2018

15. Conclusion
The study of Tribology is important so as to increase the efficiency of any machine components or parts which has relative motion between them due to which friction and wear occurs in the machine or component.
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11/17/2018

16. References http://en.wikipedia.org/wiki/Tribology
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11/17/2018