Description of the temperature field in pulsed-arc welding of superalloy thin-sheet joints with different weld edges grooving

Abstract

This article presents the development of a numerical model for describing the penetration shape during pulsed-arc GMA welding of EP648 superalloy butt welded joints with a thickness of 2 mm on a copper backing. The model takes into account symmetrical and asymmetrical edge grooving, the energy characteristics of the pulsed arc with a 1 mm diameter consumable electrode, and heat dissipation into the copper backing from the reverse side of the weld. Analysis of the modeling results showed that a double Goldak ellipsoid heat source can be used to describe the penetration shape during pulsed-arc GMA welding of joints with a symmetrical edge grooving of 30° and an asymmetrical edge grooving of 50°. However, this heat source model only approximately describes the heat transfer process in the near-affected zone and the near penetration zone from the edge.