X100管线钢在盐渍土壤模拟溶液中的腐蚀行为

Corrosion Behavior of X100 Pipeline Steel in Simulated Solution of Alkaline Soil

采用失重法和电化学测试方法,并结合SEM,EDS和XRD测试,研究了X100管线钢在盐渍土壤-库尔勒土壤模拟溶液中的腐蚀行为与机理。结果表明:在库尔勒土壤模拟溶液中,X100管线钢的腐蚀为典型的活性溶解。随着腐蚀时间的延长,腐蚀趋势逐渐增大。平均腐蚀速率与瞬时腐蚀速率均呈现增大、减小再增大的趋势。EDS和XRD结果表明,腐蚀产物分为3层,表层为质地较疏松的棕红色γ-FeOOH,内层为较致密的黑色Fe3O4及少量FeS,中间层为黑色疏松态Fe3O4及FeS。Cl-对X100钢的腐蚀起主导作用,少量的SO42-也参与腐蚀反应,对腐蚀有一定影响。

The corrosion behavior of X100 pipeline steel in an artificial solution which aims to simulate the alkaline soil medium at Korla area of Xinjiang were investigated by weight-loss, electrochemical measurement, scanning electron microscopy(SEM) with energy dispersive spectrometer(EDS) and X-ray diffractomater(XRD). Results show that the corrosion behavior of X100 pipeline steel in the simulated solution is a typical active dissolution corrosion. The corrosion tendency gradually increases with time. The average corrosion rate and the instantaneous corrosion rate all increase first, then decrease and increase again finally. The corrosion products exhibit a three layered structure composed of a surface layer of loosened brown red γ- Fe OOH, a middle layer of black loosened Fe3O4 and Fe S and an inner layer of dense black Fe3O4 and Fe S. It is also found that Clplays an important role in X100 steel corrosion, and a small amount of SO42-is also involved in the reaction which has certain influence on the corrosion.