Orientation and temperature dependences on fatigue crack growth (FCG) behavior of a Ni-base directionally solidified superalloy
Fatigue crack growth (FCG) behaviors of a widely-used nickel-based directionally solidified (DS) superalloy were investigated. Direct-current potential drop method was employed to capture the crack length according to ASTM E647. Standard compact tension (CT) specimens in longitudinal, transverse and diagonal directions were cast and tested at T0 and T0+2500C to reveal the orientation and temperature dependence. Moreover, the post-test fractography were observed through SEM and OM to understanding the underlying mechanism responsible for the fracture modes. Results suggested that cracks in all three orientations propagated transgranularly, no obvious differences were found between each other, and thus, the orientation dependence appeared to be very weak, all da/dN-DK curves in three orientations fell into one narrow band. However, temperatures showed significant dependence in diagonal directions, while in transverse direction the dependence became weak and even none in longitudinal orientation. Finally, methods for characterizing the FCG behaviors in different orientations and at both temperatures were proposed, which were able to explain the orientation and temperature dependences.
Fatigue crack growth directionally solidification nickel-based superalloy
Yangyang Zhang Huiji Shi Jialin Gu Changpeng Li Kai Kadau Oliver Luesebrink
Department of Engineering Mechanics,Tsinghua University,Beijing 100084,China Corporate Technology,Siemens Ltd.China,Beijing 100102,China Siemens Energy Inc.,Charlotte,USA Siemens AG Energy,Mulheim an der Ruhr,Germany
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）