Tribological behavior of austempered ductile iron (ADI) obtained at different austempering temperatures

Abstract

The tribological behavior of austempered ductile iron (ADI) obtained at different austempering temperatures is investigated. The microstructure of ADI is consisted of spheroidal graphite, retained austenite and acicular ferrite. The volume fraction of retained austenite and the thickness of acicular ferrite increase with increasing austempering temperature, which results in strength reduction but plasticity increasement. With the increase of austempering temperature, the friction coefficient changes little under low load (5 N) but decreases under high loads (10 N and 15 N), whilst the wear rate increases under low load (5 N) but changes little under high loads (10 N and 15 N). This wear behavior is attributed to the combined effects of hardness and friction coefficient. Additionally, adhesive and abrasive wear are main failure mechanisms for ADI under dry sliding wear condition.