摘要
在610℃下,对超超临界火电机组用P92钢主蒸汽管道的焊接接头进行了蠕变-疲劳交互作用裂纹扩展试验。获得了蠕变-疲劳裂纹扩展速率,并进行了高温断裂参量的表征,同时,结合P92钢焊接接头蠕变与拉伸试验,建立了P92钢焊接接头材料与时间相关的失效评定曲线(TDFAD)。研究结果表明,试样断口微观形貌特征显示出其蠕变–疲劳交互作用下的裂纹扩展主要是由蠕变因素主导的。每条蠕变裂纹扩展速率与高温断裂参量C*的关系曲线中均存在一个拐点,这个拐点的产生过程即为蠕变裂纹扩展的孕育阶段。采用修正R6中Option2的方法建立了TDFAD,该方法充分考虑了蠕变因素的影响,能够获得较安全的评定结果。
Stress controlled creep-fatigue interaction crack propagation test for P92 welded joint of USC main steam pipe was investigated at 610℃. The crack growth rate and high temperature fracture parameters have been obtained. And combine with the welded joint of creep and tensile test, time dependent failure assessment diagram（TDFAD） was constructed. The research results show that the damage of specimens was controlled by creep, which is seen form the micro fracture feature of specimens. There is an inflexion at every correlation curves between crack growth rate and high temperature fracture parameter C＊, which shows the crack is in growth inoculation stage. Using modified R6 Option2, the TDFAD is obtained and the effect of creep-fatigue interaction is considered. The safer assessment result can be gained.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2017年第4期1160-1166,共7页
Proceedings of the CSEE
基金
国家重点研发计划项目(2016YFC0801905)~~
关键词
P92钢焊接接头
蠕变-疲劳交互作用
裂纹扩展
高温断裂参量
失效评定曲线
610℃
P92 steel welded joint
creep-fatigue interaction
crack growth
high temperature fracture parameter
time dependent failure assessment diagram（TDFAD）
610℃
