TRIBOLOGICAL REINFORCEMENTS FOR CYLINDER LINER OF ALUMINUM - EXAMPLE COMPRESSORS FOR BRAKE SYSTEMS OF TRUCKS AND BUSES

Abstract

Aluminum gained in importance as a material for lightweight design of reciprocating engines and compressors. The application of aluminum alloys contributes to lower fuel consumption and exhaust emissions. The benefit of using aluminum is evident due to the reduced weight of the parts, but in parallel there is a problem due to the lower strength of this metal. Surface texturing and oils of low viscosity are used successfully to improve the tribological characteristics of sliding parts. For research purposes, the inner surface of cylinder which was produced of aluminum was reinforced by integrating tribological inserts. Their task is to reduce friction and wear between the piston and cylinder and to increase strength of the cylinder liner. Tribological optimization was made on the basis of the measurement results of the coefficient of friction. It is confirmed that the tribological properties of the cylinder with the tribological reinforcements are more optimal, compared to the case of aluminum construction (coating or honing of the cylinder liner). For this purpose, is currently being brought into operation the test bench in the Laboratory for Engines as well as Tribology of the Faculty of Engineering University of Kragujevac.