中文摘要：

研究LC4CS铝合金经EXC0溶液腐蚀后的截面轮廓线，提出了蚀坑特征自动识别和尺寸测量的方法。对预腐蚀件进行疲劳试验，腐蚀严重降低了试件的疲劳寿命。以测得的蚀坑深度h、长宽比AR和截面积As为参数将蚀坑等效成半椭圆和半圆形初始裂纹预测剩余寿命，h和As都是蚀坑等效的有效参数，半椭圆和半圆形裂纹应分别以h、As的平均值和最大值为等效参数。

英文摘要：

The cross-sectional profiles of pre-corroded LC4CS in EXCO solution were analysed, and a method to identify the pit feature and measure the pit sizes automatically was proposed. Fatigue experiments of pre-corroded specimens were conducted, corrosion has reduced fatigue life observably. The residual life of pre-corroded specimens were predicted by equaling pit damages as semi-elliptic and semi-circular initial cracks using the measured depth h, aspect ratio AR and cross-sectional area As of the pits as equivalence parameters, h and As are effective parameters for pit equivalence, semi-elliptic and semi-circular cracks should use the average and maximum value of h or As as equivalence parameters respectively.