scope:

An experimental study was conducted on ASTM A588 Grade A and ASTM A572 Grade 50 microalloyed steels submerged arc welded with Linde 40B weld metal to determine the fracture properties of base plates, weld metal and heataffected zones. The effects of plate orientation, heat treatment, heat input, and postweld heat treatments on heataffected zone toughness were included in the investigation. Tensile properties were evaluated for the weld metal and base plates. Hardness tests were done on weld heat-affected zones (HAZ). Charpy impact tests were performed over a temperature range for plates, welds and heat-affected zones. The nil-ductility transition temperature was determined for the plates and the weld metal. The weld metal tensile tests showed that the Linde 40B weld metal overmatched the baseplates in strength. Postweld heat treatment had minimal effect on either the strength or ductility of this weld metal.