Effect of Heat input on Submerged Arc Welded Plates

Abstract

This paper is focused on deriving an analytical solution to predict the transient temperature distribution on the plate during the process of Submerged Arc Welding (SAW). An analytical solution is derived from the transient three-dimensional heat conduction equation. The energy input that is applied on the plate is taken as the volume of heat lost from the electric arc and the kinetic energy of filler droplets specifically driven by gravity, electromagnetic force, arc drag force, carring mass, momentum and thermal energy. These driving forces periodically impinge onto the base metal, leading to a liquid weld puddle. The electric arc is assumed to be a moving double central conicoidal heat source with a close proximity to a Gaussian distribution. It is observed that the predicted values are in good agreement with the experimental results. HAZ width calculation is also done with the help of the analytical solution of the transient-three dimensional heat conduction equation. Analyses of micro-structural changes are critically investigated to comprehend the HAZ softening and phenomena.