Investigation on creep crack growth rate in heat affected zone of welded joint for 9 ％ Cr ferritic heat resistant steel
The CCG (creep crack growth) test was carded out on the compact tension (CT) specimen machined out from weldment of P92 steel pipes. The CT specimen was notched using electrical discharge method,for a sharp starter crack. The starter crack was located in the center of HAZ (heat affected zone) in order to study crack initiation and growth in HAZ.The tests were carded out at 650℃ for HAZ and base metal (BM) of P92,and the CCG rate was correlated with crack tip parameter,C*,in the extensive creep regime according to ASTM E1457. It was found that the CCG rate correlated well with C* for HAZ and BM. In addition,the post-test metallographic examination showed that the crack deviated to the fine-grain HAZ (FGHAZ) from the centre of HAZ,and grew within it. The result confirmed that the fine-grain HAZ is the more vulnerable weldment constituent to crack initiation and propagation,and suggested that the crack could move to the Type Ⅳ position for P92 steel welded joint.
Creep crack growth C* Heat affected zone P92
Lianyong Xu Hongyang Jing Junchao An Delu Xu
School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China China Electric Power Research Instituite,Beijing 100192,China
国际会议
Fracture Mechanics and Applications 2008(国际断裂力学2008年年会)(FM2008)
杭州
英文
271-274
2008-10-31（万方平台首次上网日期，不代表论文的发表时间）