D32海洋平台用钢在浪溅区腐蚀行为

Corrosion behavior of D32 steel for offshore platforms at the splash zone

通过极化实验和阻抗实验研究了D32海洋平台用钢在浪溅区的腐蚀规律,并利用扫描电镜和能量色散谱仪分析了各钢样的腐蚀产物.结果表明,腐蚀产物的形貌成分和覆盖度的不同导致了模拟全浸区腐蚀速率稍大于钢样在海水中的腐蚀速率,模拟浪溅区腐蚀速率远大于模拟全浸区钢样腐蚀速率.钢样在青岛海水、埕岛海水的全浸区和浪溅区的Nyquist图中出现的韦伯阻抗是由于表面形成的锈层及钙镁层所致.

The corrosion behavior of D32 steel for offshore platforms was studied at the splash zone with polarization curves and electric impedance spectroscopy （EIS）. Scanning electron microscope （SEM） and energy dispersive spectrometer （EDS） were employed to analyze the corrosion rusts. Because of different microstructures, components and cover degrees of the corrosion rusts, the samples at the immersion zone corroded a little more seriously than those at the seawater, whereas the samples at the splash zone corroded much more seriously than those at the immersion zone. It was due to the rust layer and calcium magnesium layer formed on the surface of the steel that the Warburg impedance appeared in the Nyquist figure at the immersion zone and splash zone of Qingdao and Chengdao seawater.