Generation of stress vs. crack length plots for a ferritic steel weld metal based on Kitagawa-Takahashi approach

Based on the concept proposed by Kitagawa and Takahashi, an attempt was made to generate different stress (S) vs. crack length (a) plots for a ferritic steel weld metal. Traditionally, Kitagawa-Takahashi (KT) diagrams have been obtained for the threshold fatigue life, i.e., infinite life cycles. Attempts were made in the present work to obtain these types of plots for various finite life cycles. These plots may be used for the prediction of stress levels for the material with different initial flaws to achieve the desired finite fatigue lives.