Crack growth behavior of SRR99 single crystal superalloy under thermal fatigue
来源期刊：Rare Metals2008年第5期
论文作者：LIU Yuan a, b, YU Jinjiang a, XU Yan a, SUN Xiaofeng a, GUAN Hengrong a, and HU Zhuangqi a a Institute of Metal Research, Chinese Academy of Sciences, Shenyang , China b Graduate School of Chinese Academy of Sciences, Beijing , China
文章页码：526 - 530
摘 要：The thermal fatigue behavior of a single crystal superalloy SRR99 was investigated. Specimens with V-type notch were tested at the peak temperatures of 900, 1000, and 1100°C. The crack growth curves as a function of the number of cycles were plotted. With the increase of peak temperature, the crack initiation life was shortened dramatically. Through optical microscopy （OM） and scanning electron microscopy （SEM） observation, it was found that multiple small cracks nucleated at the notch tip region but only one or two of them continued to develop in the following thermal cycles. The primary cracks generally propagated along a preferential direction. Microstructure changes after thermal fatigue were also discussed on the basis of SEM observation.
LIU Yuan a, b, YU Jinjiang a, XU Yan a, SUN Xiaofeng a, GUAN Hengrong a, and HU Zhuangqi a a Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China b Graduate School of Chinese Academy of Sciences, Beijing 100039, China
摘 要：The thermal fatigue behavior of a single crystal superalloy SRR99 was investigated. Specimens with V-type notch were tested at the peak temperatures of 900, 1000, and 1100°C. The crack growth curves as a function of the number of cycles were plotted. With the increase of peak temperature, the crack initiation life was shortened dramatically. Through optical microscopy （OM） and scanning electron microscopy （SEM） observation, it was found that multiple small cracks nucleated at the notch tip region but only one or two of them continued to develop in the following thermal cycles. The primary cracks generally propagated along a preferential direction. Microstructure changes after thermal fatigue were also discussed on the basis of SEM observation.
关键词：
