Slag-Metal Reactions in Submerged Arc Welding:An Overview

The requirements placed on welding fluxes and the resulting slag are numerous. For instance the flux and the resulting slag must be able to contribute to arc stability, weld metal alloying, weld metal deoxidation, weld metal protection, ease of slag detach- ability, control of inclusions due to slag entrapment, hence the resulting mechanical properties, control of porosity, facilitating welding in various positions, among others (1, 2, 3). However, these requirements can be better fulfilled only if there is a good understanding of the many reactions occurring simultaneously at the slag metal interface during welding (1). This is because there are extremely complex interconnections between the aforementioned requirements and the reactions occurring at the slag metal interface. The aim of this article, therefore, is to present a simple overview of slag-metal reactions occurring during submerged arc welding.