Effect of Chromium on the Corrosion Behavior of Powder-Processed Fe-0.35 wt % P Alloys

Yashwant Mehta, Shefali Trivedi, K. Chandra, P.S. Mishra

Indian Institute of Technology, Roorkee- 247667, Uttarakhand, India.

DOI: 10.4236/jmmce.2009.87044                

Abstract

The corrosion behaviour of phosphoric irons (i.e. Fe-P alloys containing low phosphorous in the range 0.1 to 0.7 wt. %) with/without addition of chromium, prepared by powder forging route was studied in different environments. The various environments chosen were acidic (0.25 M H₂SO₄ solution of pH 0.6), neutral/marine (3.5 % NaCl solution of pH 6.8) and alkaline (0.5M Na₂CO₃ + 1.0 M NaHCO₃ solution of pH 9.4). The corrosion studies were conducted using Tafel Extrapolation and Linear Polarization techniques. The studies compare electrolytic Armco iron with phosphoric irons. It was observed that, chromium improved the resistance to corrosion in all the environments. Corrosion rates were higher in acid medium due to the enhanced hydrogen evolution and hence, the cathodic reaction. The corrosion rates were minimal in alkaline medium and low in neutral solution.

Keywords

Phosphoric Iron, Corrosion, Powder Metallurgy, Forged, Ancient iron.

Conflicts of Interest

The authors declare no conflicts of interest.

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