多相流动淡水体系中碳钢的冲刷腐蚀行为

利用圆桶式冲刷腐蚀实验机 ,在含砂淡水体系中进行了几种碳钢的冲刷腐蚀失重实验和线性极化电阻测试 ,讨论了冲刷腐蚀作用的机理 .结果表明水流速度加快 ,含砂粒径增大 ,冲刷腐蚀失重增加 ;但当水流速度、砂粒粒径超过一定范围后 ,冲蚀失重的增加变得不明显 .碳钢在水体流动条件下的极化电阻比静态下要小得多 ,在两相含砂水流中的极化电阻比单相水流中小 .实验条件下 ,碳钢的冲刷腐蚀是机械磨损和电化学腐蚀共同作用的结果 ,但随着水流速度的增加 ,机械冲刷的贡献逐渐占主导

EROSION-CORROSION BEHAVIOR OF CARBON STEELS IN MULTIPHASE FLOWING FRESHWATER WITH SAND

In this paper , erosion-corrosion experiments of four kinds of carbon steels in multiphase flowing freshwater with sand were carried out using a tubbish erosion-corrosion device and linear polarization technique. The results show that erosion-corrosion rate of carbon steel increases with the increasing of flowing velocity and solid particle size, but the increment is not obvious beyond a certain extend. The R p value of the steels in flowing water are much lower than that in static water and the existing of particles also can reduce the R p value. Under the test conditions, the erosion-corrosion is a interaction process of mechanical erosion and electrochemical corrosion. However with the increasing of the water flowing velocity ,the contribution of mechanical erosion become the major factor gradually.