LAUSR

Abstract The main objective of this research work is to examine experimentally the tribological performance of polymeric viscosity index improver (VII) in boundary/mixed and hydrodynamic lubricated concentrated contact by simulating non-conformal and conformal geometry in the versatile multispecimen tribotester. Three different experimental approaches (Four ball tester, pin on roller tester and journal bearing test rig) were used to study Polyisobutylene (PIB) as VII. The ability of Polyisobutylene (PIB) blends to reduce friction and wear on the solid/liquid interface has been observed to depend strongly on the polymer concentrations. This study is useful for reducing wear and friction significantly for 15% concentration by weight of PIB blend in paraffinic low viscosity base oil N150. For higher concentration studied, the friction was observed eventually increase giving antagonistic behaviour with base oil.