Effect of cold Pilger rolling followed by annealing on fatigue crack initiation in Zircaloy-4 alloy cladding tube

In this study, low cycle fatigue behavior of Zircaloy-4 alloy cladding tube manufactured by cold Pilger rolling and annealing was investigated at room temperature. Results revealed that fatigue cracks initiated toward the marked side on clamped position i.e. on outer wall of the tube. Besides, substantial microstrain and dislocation developed on the out wall surface of the tube during manufacturing stage, which playing a key role in the fatigue crack initiation of the specimens. Meanwhile, effects of grain size and texture of the out wall surface, inner wall surface and cross section remained almost indifferent in this regard.

Automated summary

This study investigated the low cycle fatigue behavior of Zircaloy-4 alloy cladding tube manufactured by cold Pilger rolling and annealing at room temperature. The results revealed that fatigue cracks initiated from the marked side on the clamped position, namely the outer wall of the tube. Additionally, substantial microstrain and dislocation were found on the outer wall surface of the tube during the manufacturing stage, which played a significant role in the fatigue crack initiation. Moreover, the grain size and texture of the outer wall surface, inner wall surface, and cross section had almost no effect in this regard.