Fatigue-crack growth in Type 304 stainless steel weldments at elevated temperatures

The propagation of fatigue cracks in gas-tungsten-arc weldments of Type 304 stainless steel was studied at 75 (24) and 1000 F (538 C). It was found that the crack growth rate for cracks propagating normal to the direction of welding decreased as the crack approached the weld, and then increased as the crack grew through the weld and out the other side. It is postulated that this is due to the residual stresses produced during the welding process, and that metallurgical variations in the weldment play a minor role.