Experimental studies on automated DC pulsed MIG welding of Monel 400 sheets

ABSTRACT

Hot-rolled Monel 400 sheets of 2 mm thickness were effectively welded by the automated DC-pulsed gas metal arc welding (DC-pulsed GMAW) process using ERNiCu-7 (NA60) filler. An L9 array has been used in this work to obtain optimal robotic welding parameters to achieve better weld quality. The weldments was subjected to microstructural examinations using optical microscopy. The chemical compounds and elements of the weldments were determined using X-ray diffraction and energy-dispersive analyses. The microhardness and tensile properties of the weldments were evaluated. The corrosion behavior of the base metal and weldments was estimated in service environments by exposing them to a 3.5% NaCl solution using a potentiodynamic polarization method. The weld zone has the highest microhardness value of 154 HV. Monel 400 weldments have lower joint strength and elongation than the base metal. In addition, weldments have a higher corrosion rate (201.1 mm/yr) than base metal (55.64 mm/yr).

KEYWORDS:

• Monel400
• GMAW
• tensile, corrosion

Acknowledgments

The author would like to acknowledge the support of National Institute of Technology, Tiruchirappalli, Tamilnadu, India; Thiagarajar College of Engineering, Madurai, Tamilnadu, India; and International Research Centre (IRC), Kalasalingam Academy of Research and Education, Krishnan Kovil, Tamilnadu, India.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.