在模拟压水堆一回路环境下测得690合金的腐蚀疲劳裂纹扩展速率，腐蚀对疲劳裂纹扩展有促进作用.采用时域分析方法分析讨论了相关载荷参数(载荷比R，频率f，应力强度因子幅值ΔK)对腐蚀疲劳裂纹扩展的影响.试验结果采用FA(FordAndresen)模型和ANL(Argonne National Lab)经验公式进行拟合，试验值与预测值吻合较好.断口微观形貌表明，空气中的疲劳断口为穿晶断裂；高温水下的疲劳断口同时出现穿晶和沿晶特征，与FA模型的机制解释吻合.
Corrosion fatigue crack growth rates of Alloy 690 have been measured in air and simulated pressurizedwater reactor (PWR) environment, and environmental acceleration of fatigue crack growth is observed. The effects of loading parameters including loading ratio R, frequency f and amplitude of stress intensity factors ΔK have been discussed and summarized by the timedomain method. Furthermore, the obtained experimental results are compared with FA (FordAndresen) model and ANL (Argonne National Lab) empirical curve, and they could fit fairly well. Fracture surface morphology reveals tansgranular crack in air fatigue and tansgranular with intergranular crack in hotwater environment, which accords well with the description of FA model.
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