Analysis of Multi-Pass welding by using design of experiment on the maintenance of ASTM A131 Grade A steel

The study consists on the analysis of the relation between multibead welding and the electric current used on maintenance welding of an ASTM A131 grade A steel, by using the shield metal arc welding process and a design of experiment to identify the factors with most influence and if there is relation between the studied factors. Between the main results the heat affected zone of the samples reached the lower extremity of the plate thickness, however the hardness values for the affected extremities show a hardness value identical to the base metal. For use in a repair situation, the desired configura-tion would be the one presenting 2 weld beads as the CP4 (1,15kJ/mm and 1,37kJ/mm) for having the lowest microhard-ness values on the welded joint.