Surface interactions and tribochemistry in boundary lubrication of hypereutectic Al-Si alloys. Póster

Abstract

Al-Si alloys are characterized with 3.3.- miniSIMS DEPTH PROFILES a range of properties which make them potential materials to substitute cast iron in automotive engines. The formation of polyphosphate films on Al-Si alloys would indicate the potential use of ZDDP in lubrication of these alloys and hence facilitate their use as replacement materials for cast iron. It has been shown that the addition of MoDTC assists ZDDP to reduce friction and wear of hypereutectic Al-Si alloys. The aim of the current work is to fully characterize these two different kinds of tribofilms formed on the Al-Si alloy, showing the different surface interactions as a function of the presence of MoDTC in the tribofilm formation, as well as the different distribution and mechanical properties of the tribofilm.