材料期刊网

采用恒温浸泡的标准试验方法,考察了4种不同合金体系船体钢在强酸性氯离子介质中的腐蚀行为,探讨了合金元素对钢腐蚀行为的影响,结果表明:Cu和Ni对钢的耐蚀性有显著影响,随着Cu、Ni含量的增加,钢的耐蚀性逐渐提高,自腐蚀电位提高,电流密度显著降低,界面电荷传递电阻明显增大.Cu是提高钢在强酸性氯离子环境中耐蚀性的主要元素,其主要机理为其以再沉积颗粒(100~500 nm)的方式在钢的表面富集,并具有较高的稳定性,该沉积颗粒钝化了钢基体,降低了钢的溶解速度.Ni元素在钢中的存在显著提高了钢的基体电位,降低了材料的腐蚀敏感性,但Ni元素在锈层中的富集特征不明显.

Corrosion behavior of four kinds of hull steels with different alloy systems were investigated in strong-ly acidic solution containing chloride ion by soaking in constant temperature which is a standard experimental method,and the effect of alloy elements on corrosion behavior of steels were discussed.The results show that there is an obvious effect of Cu and Ni on corrosion resistance of steels.With the increasing of content of Cu and Ni,the corrosion resistance of steel improved gradually,natural corrosion potential and interfacial charge transfer resistance increased obviously,conversely,corrosion current densities decreased significantly.Cu is the main alloy element for improving the corrosion resistance in strongly acidic solution containing chloride ion. The primary mechanism to improve corrosion resistance is that Cu in the way of redeposit particle(100-500 nm)concentrate in steel surface with a high stability.The dissolving rate of steels decrease via this kind of re-deposit particle which can passivate base material.The existing of Ni on steel increases the corrosion potential of base material obviously,and reduces the corrosion susceptibility of steel.However,the characteristic of concentration of Ni is not obvious.