Study of damage mechanisms and failure analysis of sintered and hardened steels under rolling-sliding contact conditions

Due to continual improvements of the powder material processing, it is possible for powder metal alloys to compete even in some of the most demanding applications. The main lure of powder metallurgy (PM) components amongst the several challenging mass production methods plays an imperative role, as saving material, energy and also provides good fatigue properties, which are equally good and substitute for the conventional methods. The investigation on the lubricated rolling-sliding contact fatigue damage mechanisms in sintered and hardened steel (FLC 4608-110HT) containing combination of closed and interconnected pores has been carried out. Rolling-sliding contact conditions are simulated in twin disc type experimental set up for various contact pressure and slide/roll ratio. The damaged surface of sintered and hardened steel is examined under image analyzer for different sliding conditions. It is observed that the peel of material and surface crack opening is seen for the higher slide/roll ratio. Wear debris analysis is also carried out by dual-ferrograph analyzer for sintered and wrought steels for comparison study. The characteristics of wear morphology and the size, shape and concentration of worn particles are also analysed for different sliding contact conditions. (c) 2006 Elsevier B.V. All rights reserved.