国产A508-3钢在模拟AP1000一回路水环境下的疲劳性能研究

反应堆压力容器（RPV）钢在一回路水环境下的疲劳性能是评价其设计寿命的重要参数。本文针对国产A508-3钢开展了模拟AP1000一回路水环境的低周疲劳性能试验研究，获得了321 ℃、155 MPa及01 ppm溶解氧水环境下的疲劳行为数据和断裂机理。研究结果表明，国产A508 3钢峰值应力随应变幅的增大而逐渐增大，疲劳试验过程中试样表现出循环硬化、循环软化和饱和3个阶段；在应变幅由02%逐渐增加至06%的过程中，疲劳周次从105逐渐降低至102；疲劳断口具有疲劳和腐蚀特征，属于典型的腐蚀疲劳断裂。

Fatigue Behavior of Domestic A508-3 Steel under Simulated AP1000 Primary Coolant Environment

Fatigue property of RPV steel is one of the most key parameters in the RPV design life evaluation. The fatigue tests of domestic A508 3 steel under the simulated AP1000 primary coolant environment were carried out, the fatigue data of 004%/s strain rate, 321 ℃, 155 MPa and 01 ppm dissolved oxygen were obtained. The results show that the peak stress increases as the strain amplitude. During the fatigue test, the specimens show three stages: Cyclic hardening, cyclic softening and saturation. Fatigue life decreases from 105 to 102, as the strain amplitude increases from 02% to 06%. The fatigue fracture surface morphology has the characteristics of fatigue and corrosion, which indicates the typical corrosion fatigue fracture.