An experimental investigation of in-plane constraint effect on local fracture resistance of a dissimilar metal welded joint
An experimental investigation of in-plane constraint effect on local fracture resistance of a dissimilar metal welded joint
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面内约束效应对异种金属焊接接头局部断裂抗力的实验研究
DOI：
10.1016/j.matdes.2013.07.058
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发表时间：
2014-01-01
影响因子：
8.4
通讯作者：
Liu, C. J.
中科院分区：
文献类型：
--
作者：
Yang, J.;Wang, G. Z.;Liu, C. J.
本文对核电站A508铁素体钢与316L不锈钢异种金属焊接接头(DMWJ)中最薄弱区域的两条裂纹(A508热影响区(HAZ)裂纹和A508/合金52Mb界面裂纹)进行了裂纹深度引起的面内约束对局部断裂抗力的影响及其机理的实验研究。结果表明，两条裂纹的局部断裂抗力对面内约束很敏感。随着面内约束(裂纹深度a/w)的增加，两种裂纹的断裂机制由韧性断裂、韧性断裂和脆性断裂转变为脆性断裂，相应的裂纹扩展阻力减小。不同面内约束试件的裂纹扩展路径偏向低强度材料一侧，主要受局部强度失配控制，而不是韧性失配。为了准确可靠地进行DMWJ结构的安全设计和失效评估，需要考虑面内约束对断裂机理和局部断裂抗力的影响。需要发展新的考虑约束效应的结构安全设计和失效评估方法。(C)2013爱思唯尔有限公司。保留所有权利。
In this paper, an experimental investigation on effect and mechanism of in-plane constraint induced by crack depth on local fracture resistance of two cracks (A508 heat-affected-zone (HAZ) crack and A508/Alloy52Mb interface crack) located at the weakest region in an Alloy52M dissimilar metal welded joint (DMWJ) between A508 ferritic steel and 316L stainless steel in nuclear power plants has been carried out. The results show that the local fracture resistance of the two cracks is sensitive to in-plane constraint. With increasing in-plane constraint (crack depth a/W), the fracture mechanism of the two cracks changes from ductile fracture through mixed ductile and brittle fracture to brittle fracture, and the corresponding crack growth resistance decreases. The crack growth path in the specimens with different in-plane constraints deviates to low-strength material side, and is mainly controlled by local strength mismatch, rather than toughness mismatch. For accurate and reliable safety design and failure assessment of the DMWJ structures, it needs to consider the effects of in-plane constraint on fracture mechanism and local fracture resistance. The new safety design and failure assessment methods incorporating constraint effect need to be developed for the DMWJ structures. (C) 2013 Elsevier Ltd. All rights reserved.