Effect of Chromium on the Mechanical Properties of Powder-Processed Fe-0.35 wt% P Alloys

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

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

DOI: 10.4236/jmmce.2009.88053                

Abstract

The role of chromium in high density Fe–P binary, Fe–P–Cr ternary alloys is observed by characterization in terms of microstructure, porosity content/densification, hardness and tensile properties. The alloys were made using a hot powder forging technique. In this process mild steel encapsulated powders were hot forged into slabs, hot rolled and annealed to relieve the residual stresses. Densifications as high as 98.9% of theoretical density have been realized. Microstructures of these alloys consist of single-phase ferrite only. Fe–0.35P, Fe–0.35P–2Cr alloys showed very high ductility. As forged and hot rolled Fe–0.35P alloy showed very high elongation and it improved further on annealing. It was observed in this present investigation that, the alloying addition, such as Cr to Fe–P based alloys caused increase in strength associated with the reduction in ductility. Alloys developed in the present investigation were capable of hot/cold working to very thin gage of sheets and wires.

Keywords

Phosphoric Iron, Mechanical properties, Powder Metallurgy, Forged, Ancient iron.

Conflicts of Interest

The authors declare no conflicts of interest.

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