|Tribology in a traditional form has been in existence since the beginning of recorded history. The scientific study of tribology also has a long history.
||500,000 to 50,000 B.C.
Lighting fires: The most primitive method appears to have been rubbing together two pieces of dry wood. This process was perfected in the course of time, & friction & heat produced by means of a stick which is made to slide rapidly to and fro upon a piece of dry, soft wood . Eventually the fire-drill, consisting s of a stick, one extremity of which is inserted in a hole bored in a piece of dry wood, while the stick itself is twirled between the hands and pressed downward ( see ancient Mexican Fire-Drill) became common.
Striking together of flints, or flint or iron pyrites to spark a fire in combustible substances was another route to fire initiation.
The invention of the rolling bearing, in the form of wooden rollers (and, by some accounts, round pebbles and stones)
to help move large, heavy objects.supporting, or bearing, an object being moved is of great antiquity, and may predate the invention of the wheel
Invention of Wheel : While slides, sledges & logs may have been used since pre-historic times, the wheel was probably invented around 8,000 B.C. in Asia. The oldest wheel known however, was discovered in Mesopotamia and probably dates back to 3,500 B.C. Curiously, the wheel was also invented in meso-america but as a toy. It did not develop into a tool there, probably due to rough terrain & a lack of pack animals.
Long before the use of petroleum oils, rendered animal fat, whale oil, vegetable oil & solids such as graphite were used as lubricants
It is said that as early as 2400 B.C. grease-like substances, oil and water were used as lubricant to reduce friction.
In a painted wall relief of an Egyptian Pharaoh’s tomb dated to around 2400 B.C., a worker is seen pouring lubricant (in this case, water) for moving statues.
Olive oil was apparently a lubricant of choice; the grave of Egyptian king Tehut-Hetep (circa 1650 B.C.) was found to contain a description of the application of olive oil to wooden planks to move large stones.
Specimens of Egyptian Chariots from around 1400 B.C. are found with what seems an early form of grease derived from animal fat on the axle.
While there are evidences showing the use of natural asphalt, most of the lubricating oil used in these times was based on animal or vegetable fat.
1st Century A.D.
By the first century A.D., the father of encyclopedic factgathering, Plinius (Pliny the Elder), had compiled a list of animal and vegetable fats in use at the time—a list that
has changed surprisingly little in the centuries that followed.
The earliest recovered example of a rolling element bearing is a wooden ball bearing supporting a rotating table from the remains of Roman Nemi ships in Lake Nemi, Italy. The wrecks are dated to 40 A.D.
Classic rules of sliding friction :
1. the areas in contact have no effect on friction.
2. if the load of an object is doubled, its friction will also be doubled.
Leonardo da Vinci (1452-1519)
Leonardo da Vinci incorporated drawings of ball bearings in his design for a helicopter around the year 1500. Agostino Ramelli is the first to have published sketches of roller and thrust bearings. An issue with ball and roller bearings is that the balls or rollers rub against each other causing additional friction which can be prevented by enclosing the balls or rollers in a cage. The caged, ball bearing was originally described by Galileo in the 17th century.
Blaise Pascal (1623–1662) studied fluid hydrodynamics and hydrostatics, centered on the principles of hydraulic fluids. His inventions include the hydraulic press which multiplied a smaller force acting on a larger area into the application of a larger force totaled over a smaller area, transmitted through the same pressure (or same change of pressure) at both locations. Pascal’s principle implies that by increasing the pressure at any point in a confined fluid, there is an equal increase at every other point in the container.
Amontons, unaware of da Vinci’s work, proposed similar laws. He theorized that friction is caused by surface roughness.
The first practical caged-roller bearing was invented in the mid-1740s by horologist John Harrison for his H3 marine timekeeper
Verified Amonton’s laws
- friction is proportional to loa
- friction is independent of contact area.
-Kinetic friction is independent of velocity
-Friction dependes upon nature of materials in contact & their coatings
- Static friction depends upon length of contact time
- theorized that at least part of frictional force must be due to cohesion between molecules of interacting surfaces.
Charles August Coulomb (1736-1806)
Working Hydraulic Press
Concept of sliding friction vs rolling friction
The thirst for animal-based products as lubes and fuels sometimes had disastrous consequences. The sperm whale was hunted nearly to extinction to meet the demand for lamp oil, for example. The search for other sources, especially petroleum, was likely spurred
in part by increasing difficulty in obtaining bio-based oils.
Isaac Babbit invented tin-based alloy for using as bearing material in steam engines. The small quantities of hard metal in a soft matrix of tin or lead create a material strong enough to bear relatively high speeds and loads yet soft enough to embed dirt or other intrusions and not seize up on a spinning shaft in case of lubrication failure
1830s & 1840s
Crude oil refining began & Crude oil based products began to be used as lubricants
Calcium grease using mineral oil, animal fat & limestone invented in USA
Petroleum oil based products became popular as lubricants
Equations for viscous flow. Published classic paper on hydrodynamic lubrication & proved that hydrodynamic pressure of liquid entrained between sliding surfaces was sufficient to prevent contact between surfaces even at very low sliding speeds.
A patent on ball bearings, awarded to Jules Suriray, a Parisian bicycle mechanic.
Theory of Elasticity
Friedrich Fischer, in Germany, developed a technique for milling and grinding balls of equal size and exact roundness
Founder of FAG
Henry Timken, in USA, patented the tapered roller bearing in 1898
Founder of TIMKEN
Motor oil invented in UK
Founder of TIMKEN
Richard Stribeck, published the Stribeck curve, a plot of friction as it relates to viscosity, speed and load.
(Weikfield, name of the oil: CASTROL)
Refinements to the formal theory of hydrodynamic lubrication .
Fluid-film thrust bearings patented by Australian engineer George Michell. Michell bearings contain a number of sector-shaped pads, arranged in a circle around the shaft, and which are free to pivot. Michell's invention was notably applied to the thrust block of propellor driven ships. Their small size (one-tenth the size of old bearing designs), low friction and long life enabled the development of more powerful engines and propellers.
Sven Wingqvist, in Sweden, invented the multi-row self-aligning radial ball bearing in 1907.
(founder of SKF)
Dr. Albert Kingsbury invented the hydrodynamic thrust bearing.
Understanding of Boundary lubrication refined
W.B. Hardy and I. Doubleday
Motor oil Filter
( PUROLATOR – from Pure Oil Later)
Pin and Vee Block tester
1930s to 1940s
The first ZDDPs began to be developed as anticorrosion agents and oxidation inhibitors. The antiwear activity of these molecules was recognized only later, in the 1950s, at
which point they became an integral part of many oil chemistries. To this day ZDDPs
remain the backbone of antiwear additive technology.
Work on Synthetic lubricants in Germany & USA
PTFE, the most famous of the self-lubricating coating materials, was discovered fortuitously during a project looking at tetrafluoroethylene as a refrigerant.
Dr. Roy J. Plunkett, Du Pont
Molybdenum Disulphide patented as a Soild lubricant
Lithium grease invented & rapidly became widely used multi-purpose grease
First realistic model providing solution for elastohydrodynamic films published by Grubin based on the combination of three effects: Hydrodynamics, Elastic deformation of metal surfaces, Increase in viscosity of oil under extreme pressure.
Physical explanation for the laws of friction. They determined that the true area of contact is a very small percentage of the apparent contact area. The true contact area is formed by the asperities. As the normal force increases, more asperities come into contact and the average area of each asperity contact grows. The frictional force was shown to be dependent on the true contact area—a much more intuitively satisfying argument than what the Amontons-Coulomb law allows.
Philip Bowden and David Tabor
Synthetic oils introduced for usage in aviation
Fire Resistant Hydraulic Fluids developed
Aluminium Complex grease invented for high temperature applications
Multi-grade motor oils introduced
Synthetic oils used for motor oils
A committee headed by Peter Jost, estimated that application of basic principles of tribology could save the UK economy approx ₤ 515 million per annum ( 1965 values)
An OECD committee formally defined Tribology as the study of friction, wear & lubrication of interacting surfaces in relative motion.
West German study concludes that economic losses caused by friction & wear cost about DM 10 Billion per annum ( 1975 values)
The development of the Atomic Force Microscope enabled scientists to study & understand friction at the atomic scale
Biolubricants developments begin
Nanotribolgy, Biotribology developments begin