Experimental Investigation on Corrosion Behaviour of Hot Upset P/M Plain Carbon Steel

The experimental work endeavors to examine the mechanism behind the corrosion phenomenon of sintered-hot upset plain carbon steel under induced corrosion acid pickling condition. The alloy powder mix of Fe-0.5%C was compacted into round specimens of size ɸ25x12mm utilizing 100T limit Universal Testing Machine (UTM) by applying necessary pressure to get 0.81 relative density Powder Metallurgy (P/M) plain carbon steel. The green compacts were sintered at a temperature of 1050±10ºC in a nitrogen purged muffle furnace for 30minutes. The sintered-hot forge upset alloy steel billets of 0.86, 0.90 and 0.98 relative densities were made to encounter aqueous corrosion attack by keeping the billets in a 250 ml pickling acid solution containing 18%HCL (Hydrochloric acid) for various time periods such as 25, 50 and 75hrs. It has been found that an increase in the density of specimens by hot upsetting results in a decrease in the number of pores present in the alloy steel. Though the plain carbon steel consists of soft ferritic-pearlitic microstructure, the densified specimens are found to be lower corrosive in action due to the formation of refined grain structure. Correlation for the corrosion rate relating density and testing time periods h