Abstract
The submerged arc welding (SAW) process is widely used in Cuban industries and it is highly reliable. The flux and wire electrode feeds are carried out simultaneously during the SAW process. The flux forms a layer, and beneath it is the wire producing the electric arc. During the deposition of the flux, a certain amount of air (1.293 g/l and filling 48% of the total layer) stays hidden among interstices between the grains. The air is formed of approximately 21% oxygen and 77% nitrogen; these gases are undesirable during the SAW process. When the granulometric distribution and the grain shape of the flux are not known, an unexpected effect can occur on the mechanical properties of the weld bead. This effect has sometimes been imputed to other problems such as incorrect previous calcinations of the flux. The conjunction of the morphological characteristics of the grain and its granulometric distribution are aspects that have not been sufficiently studied, in relation to the air potentially occluded in the free spaces between the grains.