Studies on Weldability of Powder-Processed Fe-0.35P-0.15C Alloy Using Gas Tungsten Arc Welding Process

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

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

DOI: 10.4236/jmmce.2010.93018                

Abstract

The objective of this study was to investigate the weldability of an iron-based powder metal alloy (Fe-P-C) using the gas tungsten arc welding process (GTAW) with two different filler metals. Optical microscopy revealed that for the Fe-P-C alloys, the fusion-welded zone was free of porosity and cracks. The thickness of the slab was 4 mm. The heat affected zone did not show excessive hardness. The SEM image of the fracture specimen showed elongated dimples. X-Ray mapping confirmed the absence of Fe3P. EPMA was used to determine the ability of carbon in preventing the segregation of P to the grain boundaries. Tensile tests showed that the failures of the specimens occurred always in the base metal with tensile strength slightly superior to the value of unwelded samples. As a result, this investigation showed the feasibility of joining ironbased powder metal alloys by the GTAW process, especially while welding the Fe-P-C alloy.

Keywords

Electron Microscopy; Hardness Measurement; Welding; Powder Metallurgy; Mechanical Characterization; Phosphoric irons

Conflicts of Interest

The authors declare no conflicts of interest.

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