The difference between thick film and boundary film lubrication are as follows-
||Boundary film lubrication
|It is also known as film or hydrodynamic lubrication.
||It is also known as thin film lubrication.
|In this case, the coefficient of friction ranges from 0.001 to 0.03.
||In this case, the coefficient of friction ranges from 0.05 to 0.15.
|The lubrication should have minimum viscosity.
||The lubricant should have more oiliness.
|The lubricant neither gets absorbed on nor chemically reacts with a metallic surface.
||The lubricants may be absorbed on or chemically reacts with metallic surfaces
|The lubricating oil forms uniform film of a thickness more than 10000A in between two moving or sliding surfaces.
||TThe lubricating oil forms uniform film of a thickness more than 1000A in between two moving or sliding surfaces.
|The oil molecules are disoriented.
||This lubrication is used in machines working under high load and slow speed.
|This lubrication is used in machines working under light and high speed.
||Bearing, gears, tractor rollers, lathes, railway track joints, concrete mixture etc.