Residual stress relaxation in typical weld joints and its effect on fatigue and crack growth

作     者：Liangbi LI Zhengquan WAN Zili WANG Chunyan JI 

作者机构：School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China China Ship Scientific Research Center Wuxi 214082 China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2009年第22卷第3期

页      面：202-210页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 080102[工学-固体力学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：supported by the National Natural Science Foundation of China(No.50609009) Natural Science Foundation of College of Jiangsu Province(No.07KJD580056) 

主　　题：Residual stress relaxation Weld joint Finite element Fatigue crack growth 

摘      要：Many factors influence the fatigue and crack growth behavior of welded joints. Some structures often undergo fairly large static loading before they enter service or variable amplitude cyclic loading when they are in service. The combined effect of both applied stress and high initial residual stress is expected to cause the residual stresses relaxation. Only a few papers seem to deal with appropriate procedures for fatigue analysis and crack growth by considering the combined effect of variable amplitude cyclic loading with residual stresses relaxation. In this article, some typical welded connections in ship-shaped structures are investigated with 3-D elastic-plastic finite element analysis. The effect of residual stress relaxation, initial residual stress, and the applied load after variable amplitude cyclic loading is revealed, and a formula for predicting the residual stress at hot spot quantitatively is proposed. Based on the formula, an improved fatigue procedure is introduced. Moreover, crack growth of typical weld joints considering residual stresses relaxation is studied.