Effect of Phosphorus Addition on Dry Sliding Behavior of Fe–P Alloys Prepared by Powder Metallurgy

Iron–phosphorus powder metallurgy (P/M) alloys having 0, 0.35 and 0.65 wt.% P have been prepared by hot-forging technique. Hot forging consists of heating encapsulated powder at a temperature of 1050 °C in the atmosphere of hydrogen gas followed by hot forging. These hot-forged specimens have been subjected to dry sliding adhesive wear test at a normal load of 19.6, 29.4, and 39.2 N, at a constant sliding speed of 2.2 m/s and for a sliding distance of 4000 m using a pin-on-disk wear testing machine. Archard wear coefficient has been found to decrease from 2.5 × 10−7 to 1.4 × 10−7 with increasing phosphorus content in the alloys. The average coefficient of friction has also been found to decrease more or less linearly with increasing load as well as with increasing phosphorus content in the alloy. The mechanism of wear is primarily oxidative in nature, which has been confirmed by SEM–EDS analysis of the worn surfaces.