模拟海洋大气条件下直流电场作用对碳钢初期腐蚀行为的影响

Effect of Direct Current Electric Field on Initial Corrosion of Steel Exposed to Simulated Marine Environment

采用失重分析、极化曲线测试和SEM分析手段,研究了模拟海洋大气环境下直流电场对碳钢初期腐蚀行为的影响。结果表明,直流电场的存在加速了碳钢的初期腐蚀速率,但并没有改变其腐蚀动力学;直流电场存在有利于具有亚稳片状结构的γ-FeOOH的形成,同时抑制了γ-FeOOH向具有保护性能的α-FeOOH的转化,从而导致锈层的保护性能下降,加速了碳钢的腐蚀。

The effect of an applied direct current（DC） electric field on the initial corrosion behavior of steels exposed in simulated marine environments was studied by means of mass change measurement, polarization tests and SEM observation. The results show that the existence of the DC electric field accelerates the steel corrosion, but does not alter the corrosion kinetics. Meanwhile the DC electric field favors the generation of the plate-shaped γ-Fe OOH and inhibits the yield of the α-Fe OOH, thereby lowers the protective ability of the rust scale. In general, the DC electric field accelerates the steel corrosion is mainly attributed to the decrease of the protective component of the formed rust scale.