Effect of Repeated Weld Repair on Austenitic Stainless Steel Welds

Austenitic stainless steel has been widely used as an ideal structural material for nuclear, petrochemical and other industries, due to its very good resistance to corrosion and other required properties. Welding is an important, inevitable and reliable joining process in the fabrication of heavy structural components. Often weld repair becomes unavoidable due to the presence of unacceptable defects specified by various codes. However, as a good practice, repeated weld repair is limited to a maximum of two times during fabrication. In practice, often more than two weld repairs become inevitable, albeit in rare occasions. Hence, a study was undertaken to find out the effect of repeated weld repair upto four times on the structural integrity and mechanical properties of the joints of austenitic stainless steel. Variation in microstructure, 5-ferrite content, hardness, tensile properties and impact toughness with number of repairs was examined. Results show the properties of the weld joint are not significantly affected by the repeated weld repair upto four times. Hence, repeated weld repair upto four times can be permitted on austenitic stainless steel welds under rare occasions that are inevitable.