SEMINAR ON ADVANCES IN TRIBOLOGYBY APURV VERMA 3RB09ME011 DEPARTMENT OF MECHANICAL ENGINEERING BHEEMANNA KHANDRE INSTITUTE OF TECHNOLOGY, BHALKI 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 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 PRACTICAL OBJECTIVES OF TRIBOLOGY . 5 . Occurs whenever two objects are IN CONTACT with each other.• What is friction? FRICTION It’s a FORCE. It SLOWS objects down. It’s the resistance to movement. F RICTION Let’s use THE SAME FORCE to move the box on: higher friction wooden floor lower friction ice In which case friction is higher? Which one will slide further? WHY? 6 . 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. WEAR MECHANISMS • Adhesive – Low contact pressures – Augmented asperities • Abrasive – High contact pressures – Wear tracks . ● Sliding motion e.Piston in IC engine ●Rolling motion e.TYPES OF MOTION There are two types of motion between two moving parts.g :.g :.Bearings. wheels of automobiles . • It can be reduced by applying lubricant.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. . 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 . > It has high pour point. . > Has good fire point about 650°F. • It is easily available at low price. > Has comparatively high flash point 610°F. it can be reduced by winterizing the soybean oil. PROPERTIES OF SOYBEAN OIL :> It has a high viscosity index up to 223.SOYBEAN OIL AS FUTURE LUBRICANT FOR IC ENGINES • Soybean oil is a vegetable oil extracted from soybean seeds. . • Ease of processing. so it reduces dependency of foreign petroleum products.MERITS OF SOYBEAN OIL • Soybean oil is biodegradable. in general it is less toxic. • It is a renewable oil. . electronic devices and sensors. fine powder and ceramic powder protective coatings. Application:• Integrated circuits.CHEMICAL VAPOUR DEPOSITION CVD is used to grow a thin layer of advanced materials on the surface of a substrate. • Catalysts • Micromachines. .CHEMICAL VAPOUR DEPOSITION Thin film is formed from gas phase components. etc.Good uniformity. nitride. Used for oxide. oxide. • PECVD (Plasma Enhanced CVD ) :. nitride.Low temperature process and high deposition rate. .CHEMICAL VAPOUR DEPOSITION • Two types of CVD:• LPCVD (Low Pressure CVD ) :. Used for poly-Si. CHEMICAL VAPOUR DEPOSITION Pressure sensor Resistance-heated furnace Quartz tube Trap To exhaust Si Wafers Pump Source gases Gas control system LPCVD Systems . . • i. whereas in CVD the precursors are introduced to the reaction chamber in gaseous state.PHYSICAL VAPOUR DEPOSITION • PVD is a fundamentally a vaporization coating technique.e. • It is an alternative process to electroplating. • The process is similar to chemical vapor deposition (CVD) except for the raw materials. the material that is to be deposited starts in solid form. involving transfer of material on an atomic level. . Wear Resistance. Thus.APPLICATIONS OF PVD • PVD coatings are used to improve Hardness. Oxidation Resistance. 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 . • Once SAMS and Diamond Coatings are more fully developed. MEMS technology will be able to more completely realize its potential.TRIBOLOGY CONCERNS IN MEMS DEVICES • Friction and Wear are the biggest issues in blocking advances of MEMS technology. . DIAMOND COATINGS • Diamond has a variety of useful properties compared to Silicon – Low wear. isotropic hardness • Diamond cannot be simply made into smaller and smaller flakes. . low coefficient of friction. thermally stable. then deposited on MEMS devices • Diamond (or diamond-like) film must be grown on surface. Grain size is 2-5nm. creating C2 (carbon “dimers”) – These C2 molecules enter the diamond lattice. . C60 is introduced into the reaction along with CH4.UNCD ULTRANANOCRYSTALLINE DIAMOND • A “better” method for producing diamond-like films. – C60 collides with itself. • Unlike conventional diamond film CVD. – An abundance of C2 is the goal of the UNCD creation process. SELF ASSEMBLED MONOLAYERS (SAMs) • Two Types • Silane – deposits on silicon • Thiol – deposits on gold • Deposition Formations • Densely Packed • Amorphous Structure • Functional group determines: • applications • hydrophilicity/hydrophobicity • Used as: • binders for subsequent molecules • lubricants • Common hydrophobic SAMS: • OTS (long chain hydrocarbon) • FDTS (long chain fluorocarbon) Deposition O O O Si Si Si Si O O O O Si Si Si Si O O O O OH OH OH OH Si Si Si Si O O O O . CANTILEVER BEAM ARRAY TECHNIQUE • Cantilever beams are fabricated of 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 Beam Structures . • 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. the application of tribological principles can effect national energy savings.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. • In UK. These are estimated at 468 to 700 million pounds per annum. • Tribology is now recognized universally and President Carter of U. • 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.IMPACT OF TRIBOLOGY • Since the publication of the Lubrication Report there has been an increasing awareness throughout industry of the subject of tribology. . 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.A.S. google.com www.H.W. RAJSHEKHAR MATHAPATI www.slideshare.com Tribology In Industries by SUSHIL KUMAR Engineering Tribology by G. JONES . STACHOWIAK Industrial Tribology by M.wikipedia.com www.REFERENCES • • • • • • • Mr. ANY QUERIES .