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在模拟压水堆环境中,对SA508 3级压力容器钢进行了腐蚀疲劳试验。试验研究的变量有空气和压水堆环境,频率变化在1～10Hz 范围,纵、横裂纹扩展方向,温度为20℃和50℃,以及R 比值为0. 2与0. 7。发现在压水堆环境中,降低试验频率,增加疲劳裂纹扩展速率,压水堆环境试验会促使裂纹扩展(与空气试验比较)。对纵向裂纹扩展来说,疲劳裂纹扩展速率是较主要的,稍微增加温度会显著加快疲劳裂纹扩展速率,个别的空气试验指出疲劳裂纹扩展速率比ASME 标准预测的大。断口组织的迹象指出疲劳裂纹扩展速率是由氢脆机理
In simulated PWR environment, SA508 grade 3 pressure vessel steel was subjected to corrosion fatigue test. Experimental and experimental variables are air and pressurized water reactor environment, the frequency changes in the range of 1 ~ 10Hz, vertical and horizontal crack propagation direction, the temperature is 20 ℃ and 50 ℃, and the R ratio of 0.2 and 0.7. It was found that in pressurized water reactor environment, the frequency of test is reduced and fatigue crack growth rate is increased. The PWR environment test will promote crack propagation (compared with air test). For longitudinal crack growth, the fatigue crack growth rate is more important. Slightly increasing the temperature will significantly accelerate the fatigue crack growth rate. Individual air tests indicate that the fatigue crack growth rate is larger than predicted by the ASME standard. The signs of fracture organization indicate that the fatigue crack growth rate is due to the mechanism of hydrogen embrittlement