Relationship of da/dN between lateral notch specimen and plane plate specimen

The relationship of crack growth rate between lateral notch specimen and plane plate specimen was studied in this paper. A formula for the relationship was established. The formula was verified by five groups of da/dN comparison test between the lateral notch specimen and the plane plate specimen, including base metal and welded joints, with four types of material and six forms of specimens. This study laid the foundation for the prediction of safety and life of welded structures.