TRIBOLOGICAL ANALYSIS OF TRIBOPAIRS OF CYLINDER LINER AND PISTON RING MATERIALS WITH AND WITHOUT CHROME PLATING

Abstract

The motor car is one of the most common machines in use today, and it is no exaggeration to state that it is crucial to the economic success of all the developing and developed nations of the world and to the quality of life of their citizens. The motor car itself consists of thousands of component parts, many of which rely on the interaction of their surfaces to function. There are many hundreds of tribological components, from bearings, pistons, transmissions, clutches, gears, to wiper blades, tires, and electrical contacts. The application of tribological principles is essential for the reliability of the motor vehicle, and mass production of the motor car has led to enormous advances in the field of Tribology. For example, many of the developments in lubrication and bearing surface technology have been driven by requirements for increased capacity and durability in the motor industry. It is observed that around 13-17% of total frictional losses occured in I.C. engine and 35-50% of total friction losses is due to piston ring assembly (PRA) system. This research work focuses on the determining the coefficient of friction and the amount of the wear developed between the cylinder liner and piston ring. A comparison is also done between the effects of chorme plated piston ring and the uncoated piston rings. It is believed that the hard chromium coating proved to be effective in reducing the friction and wear in considerable amount. A Tribotester of pin on disc type is used for determining the friction force and wear amount. In the End of this research work, it is seen from the results that the application of the chorme coating is having positive results on the service life of the piston ring. The specific wear rate and the coefficient of friction values for chrome coated pin were reduced by considerable amount when compared with the uncoated pin.