中文摘要：

对在EXCO溶液中预腐蚀后的LC4CS光滑试件和缺口试件进行疲劳试验，得到不同预腐蚀时间的S—N曲线及预腐蚀疲劳缺口系数。通过分析腐蚀过程，阐述了腐蚀对疲劳缺口系数的影响机理，建立了描述预腐蚀疲劳缺口系数的两参数模型，并进行了试验验证。结果表明：LC4CS材料的疲劳缺口系数随预腐蚀时间呈现出先降后升的变化趋势，其拐点出现在剥蚀开始阶段。

英文摘要：

The notched and smooth specimens of aluminum alloy LC4CS soaked in EXCO solution for different time are tested under the constant amplitude cyclic loading to obtain S-N curves and fatigue notch factors with different pre-corrosion time. By analyzing the corrosion process of LC4CS specimens in EXCO solution, the influ- ence mechanism of corrosion on fatigue notch factor is expounded. Then, a two-parameter model used to describe the change of corrosion fatigue notch factor with time is established and verified by experiment. The results show that the pre-corrosion fatigue notch factor of LC4CS material decreases at first and then increases with the increasing pre-corrosion time. The inflection point appears at the beginning of denudation stage.