Evaluation of HAZ Fracture Toughness of Welded Joints with Strength Mis-Matching by the Local
Evaluation of HAZ Fracture Toughness of Welded Joints with Strength Mis-Matching by the Local
复制标题
局部强度失配焊接接头热影响区断裂韧性评价
DOI：
10.2534/jjasnaoe1968.1996.180_565
复制
发表时间：
1996
期刊：
影响因子：
--
通讯作者：
M. Toyoda
中科院分区：
文献类型：
--
作者：
M. Ohata;F. Minami;M. Toyoda
在这项研究中，局部方法被应用于评估母材和焊缝金属之间强度失配的HAZ缺口试样的抗解理断裂性能。为了验证缺口处强度匹配对断裂抗力影响的基础性研究，采用均质试样和缺口处仅存在强度匹配的模型试样，采用局部方法研究缺口处强度匹配对断裂抗力的影响。利用均匀试件的临界威布尔应力，预测了强度超匹配效应和强度欠匹配效应对临界CTOD值的影响。观察到的临界CTOD值预测和实验获得的结果之间的密切协议。考虑到几乎所有试样的断裂起始点都位于CGHAZ（LBZ：Local Brittle Zone），对强度失配的HAZ缺口试样（匹配和超匹配试样）的Weibull应力进行了评估。结果表明，无论是否存在强度失配，由CGHAZ控制的HAZ缺口试样的解理断裂抗力都可以通过使用Weibull应力来均匀处理。
In this study, the local approach was applied to evaluate the cleavage fracture resistance ofHAZ-notched specimens with strength mis-matching between the base and weld metals. The main purpose of this study is to demonstrate that the critical Weibull stress at fracture initiation of HAZ-notched specimens can be material property independent of strength mis-matching.For the fundamental study to discuss the effect of strength mis-matching near the notch on the fracture resistance by the local approach, homogeneous specimens and model specimens with only strength mismatching near the notch were used. By using the critical Weibull stress obtained for the homogeneous specimen, strength overmatch effect and undermatch effect on the critical CTOD value were predicted. Close agreement was observed between the critical CTOD value predicted and that obtained by the experiment. As a result, independence of strength mis-matching on the critical Weibull stress was verified.The Weibull stress for the HAZ-notched specimens with strength mis-matching (match and overmatch specimens) was evaluated in consideration of that almost all specimens have fracture initiation points in the CGHAZ (LBZ : Local Brittle Zone). It was demonstrated that the cleavage fracture resistance for the HAZ-notched specimens controlled by the CGHAZ can be uniformly treated by using the Weibull stress irrespective of the existence of strength mis-matching.