[3F10-11] Zirconium Alloys

[3F11] Evaluation of irradiation induced hardness and microstructure of Zry-2 under applied stress (2)

*Luwei Xue¹, Hideo Watanabe¹ (1. Kyushu Univ.)

Keywords:Zirconium alloy, Applied stress, Dislocation loop, Ion irradiation, Energy-dispersive spectroscopy

Zircaloy-2 is used as the fuel cladding tube in boiled water reactors. The previous experimental results showed the formation and evolution of a-loops during the initial stage of irradiation, which leads to significant radiation-induced hardening. As the irradiation dose rises to a higher level, hydrogen content increases dramatically, and hydrides are formed, along with the appearance of c-loops. To understand the behavior of the material, EDS analysis and observation of microstructural changes were conducted on samples after different ion irradiation conditions. The dissolution of Fe-rich precipitates was detected. However, the effect of stress and temperature on the dissolution rate of Fe-rich precipitates was minor.