中文摘要：

研究了不同程度渗氢处理Zr-4合金的双轴循环变形行为。结果表明：当氢含量为CH=400μg/g时，在相同等效应变幅和相同相位角下，渗氢Zr-4合金的疲劳寿命高于原始冷变形状态Zr-4合金。当氢含量增加到CH=580μg/g时，渗氢处理Zr-4合金的双轴疲劳寿命却低于原始冷变形状态的Zr-4合金。透射电镜和金相显微镜观察表明，冷变形Zr-4合金渗氢后析出的氢化物具有良好的塑性变形能力，渗氢过程中中温条件下长时间保持导致基体产生去应力退火效应是Zr-4合金疲劳寿命提高的主要原因。

英文摘要：

The effects of hydrogen-charged treatment on the biaxial cyclic deformation behavior and the fatigue lifetime of cold-worked Ziraloy-4 have been investigated. The results show that the fatigue lifetime of hydogenated Ziraloy-4 under the cold-worked condition with CH =400μg/g is better than in the unhydrogenated one. Whereas, when CH =580μg/g, the fatigue lifetime of cold-worked hydrogenated Ziraloy-4 alloy is lower than the unhydrogenated Zircaloy-4 at the equivalent strain amplitudes （△εcq =0.8%） and the same phase angle （φ）. Microstructure examination by means of TEM and optical microscope reveals that the improvement of fatigue lifetime for the hydrogenated Ziraloy-4 alloy in the low hydrogen concentration can be attributed to the relieve of the residual stress during hydrogenating treatment at elevated temperature, which leads to the good abilities of plastic deformation and harmony with matrix for hydride formed in Ziraloy-4.