S. Maheshwari, Netaji Subhas Institute of Technology, N. Delhi, India; S. Pandey, Indian Institute of Technology Delhi, New Delhi, India
Since the inception of submerged arc welding process, a wide variety of fluxes have been developed and a large number of flux electrode base plate combinations have been in use for welding of various types of steels. The flux formulations have however, been done primarily on the basis of empirical data as well as the practical experience. This approach has limited applicability because it lacks the necessary scientific basis required to formulate the flux. Engineering requirements demand innovative approaches to the formulation and manufacture of welding consumables. In the present study, CaO-Al2O3 - TiO2 based fluxes with minor additions of CaF2 and MgO have been designed on the basis of binary and ternary phase diagrams for different oxide and fluoride systems. The fluxes have been designed and characterized with an objective approach. Further, the tools developed have been found effective in recording the metal transfer and correlating the same with bead geometry and shape relationship parameters. Recording of standard deviation in the voltage and current value has given a fair idea about the bead geometry. It was also noted that the effect of CaF2 content on the bead penetration can not be linked directly to the penetration values even when CaF2 is responsible for changing the viscosity of molten flux.
Summary: This work is an attempt to have an objective assessment criterion to design and evaluate welding fluxes for Submerged Arc Welding.
