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测量了A537钢在3．5％NaCl中阴极极化条件和不同间歇超载发生频率下的疲劳裂纹扩展曲线，并利用扫描电子显微镜对腐蚀疲劳断口进行了观察结果表明：超载对裂纹扩展速率及断口特征的影响取决于超载发生频率．当超载发生频率OCR＝10(-1)，10(-2)时，间歇超载加速裂纹扩展，腐蚀疲劳断口只存在解理、沿晶等一般脆性特征；当OCR＝10(－3)，2×10(－4)，10(－4)时，间歇超载对裂纹扩展存在阻滞效应，A537钢断口上能观察到铁素体、珠光体两种组织，且阻滞效应越大，两种组织越清晰．分析表明，这种断口形态的形成是氢在组织界面附近大量富集而使界面强度降低，铁素体、珠光体以不同方式开裂的结果．
The fatigue crack propagation curves of A537 steel in 3.5% NaCl under cathodic polarization and different intermittent overload were measured. The corrosion fatigue fracture was observed by scanning electron microscope. The results showed that the fatigue crack growth rate and fracture The impact of the characteristics depends on the frequency of overloading. When the overload frequency OCR = 10 (-1), 10 (-2), the intermittent overload accelerates the crack growth, and the corrosion fatigue fracture has only the general fragility characteristics such as cleavage and intergranular; when OCR = 10 × 10 (-4), 10 (-4), there is a retardation effect on crack propagation by intermittent overload. Two kinds of ferrite and pearlite can be observed on the fracture surface of A537 steel, The clearer the organization. The analysis shows that the formation of this fracture morphology is the result of a large amount of enrichment of hydrogen near the interface of the structure, which leads to the decrease of interface strength and the cracking of ferrite and pearlite in different ways.