Effect of sintering parameters on the corrosion characteristics of Iron-Alumina metal matrix nanocomposites

Abstract

The present paper reports the effect of sintering parameters (i.e. temperature and time) on the corrosion characteristics of Iron (Fe) - Alumina (Al2O3) metal matrix nanocomposites (MMNCs) synthesized by powder metallurgy (P/M) technique tested in freely aerated 1 N HCl solution and compared with that of pure iron specimen. The composite for the present investigation contains 10% Al2O3 and 90% Fe. The composites were prepared by ball milling followed by compaction and then sintering the specimens in an inert atmosphere in the temperature range of 900-1100°C for 1 to 3 hour. Phase and microstructure of the prepared nanocomposite specimens showed the presence of nano size iron aluminate (FeAl2O4) phase which is formed due to reactive sintering. It was found that the formation of nano iron aluminate improved the corrosion resistance of Fe-Al2O3 nanocomposites. XRD pattern of the corroded specimen showed the presence of aluminum chlorate (AlCl3O12) phase along with iron (Fe), aluminum oxide (Al2O3) and trace amount of iron chloride (FeCl2) phases. SEM studies also showed the formation of nano size particles of constituent phases.