Effect of processing parameters on the surface durability of steam-oxidized sintered iron

Surface durability has been reported to be the main factor affecting the tribological behavior of steam-oxidized sintered iron. In this paper, the influence of compaction pressure and powder grade on the surface durability of steam-treated sintered iron is analyzed. Specimens prepared from atomized powders in different sizes were compacted using four different pressures, sintered for 30 min at 1120°C and then subjected to a continuous steam treatment at 540°C for 2 h. The tribological characterization was carried out against a hard steel ball in a reciprocating wear test, in which the electrical contact resistance between the sliding surfaces was continually monitored. The processing parameters had a strong influence on the oxide durability, expressed in terms of the sliding distance required to achieve low contact resistance. High durability was always associated with high compaction pressure and smaller powder size.