Microstructure and Dry Sliding Wear Behavior of AA2218 Based Self-Lubricating Metal Matrix Composites

Abstract

AA2218 based self-lubricating metal matrix composite was prepared with 5, 10 & 15 weight percent of fly ash and 4 weight percentage of MoS2. Dry sliding wear behavior of self lubricating composite was tested at room temperature by pin on disc wear testing apparatus. Wear rate, Coefficient of friction and volume loss of self lubricating composite has been tested as the result of applied load, sliding velocity and weight percent of fly ash particles. From this investigation it was observed that the wear rate increases with the increasing load, at the same time wear rate and coefficient of friction get reduced to increase in wt. % of fly ash particles. Another dominant factor is the formation of the tribochemical layer at the interface, which was formed by MoS2. Formation of tribochemical layer was clearly observed from SEM micrographs. This study reveals that wear resistance of the self-lubricating composites containing 15 wt. % fly ash and 4 wt. % MoS2 has been superior to that of the other compositions.