Abstract In this study corrosion-fatigue tests have been conducted on fracture mechanics specimens extracted from an S355 G10+M structural steel welded plate. The tests have been performed on compact tension specimens with the crack tip located in the heat affected zone. The corrosion-fatigue test results from this study have been compared with the data available on the base metal as well as air tests on the same material. Moreover, the obtained results have been compared with the corrosion-fatigue data available in the literature on a wide range of steels and also the fatigue trends for welded joints in free-corrosion condition recommended in the BS7910 Standard. The effect of the specimen orientation, with respect to the weld region, is also examined in this study and it has been found that higher corrosion-fatigue crack growth rates are generally observed in the tests with 0° orientation. The results have also shown that the corrosive environment has significant effects on the fatigue crack growth acceleration at the beginning of the tests; however, as the crack propagates, the environmental damage effect on crack growth behaviour becomes less pronounced. The results presented in this study are discussed in terms of improvement in the structural integrity assessment of offshore wind turbine monopiles.

中文翻译：

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裂纹扩展方向对海上风机钢焊件腐蚀疲劳行为的影响

摘要 在这项研究中，对从 S355 G10+M 结构钢焊接板中提取的断裂力学试样进行了腐蚀疲劳试验。试验是在裂纹尖端位于热影响区的紧凑拉伸试样上进行的。本研究的腐蚀疲劳试验结果与基础金属的可用数据以及相同材料的空气试验进行了比较。此外，获得的结果已与文献中关于各种钢的腐蚀疲劳数据以及 BS7910 标准中推荐的自由腐蚀条件下焊接接头的疲劳趋势进行了比较。试样方向的影响，相对于焊缝区域，在本研究中也进行了检查，并发现在 0° 取向的测试中通常观察到更高的腐蚀疲劳裂纹扩展速率。结果还表明，腐蚀环境对试验开始时的疲劳裂纹扩展加速度有显着影响；然而，随着裂纹扩展，环境破坏对裂纹扩展行为的影响变得不那么明显。本研究中提出的结果在改进海上风力涡轮机单桩的结构完整性评估方面进行了讨论。环境破坏对裂纹扩展行为的影响变得不那么明显。本研究中提出的结果在改进海上风力涡轮机单桩的结构完整性评估方面进行了讨论。环境破坏对裂纹扩展行为的影响变得不那么明显。本研究中提出的结果在改进海上风力涡轮机单桩的结构完整性评估方面进行了讨论。